CN1728006A

CN1728006A - The imaging device and the manufacture method of the image error that minimizing is caused by image carrier

Info

Publication number: CN1728006A
Application number: CNA2005100913843A
Authority: CN
Inventors: 金炫秀; 朴根用; 洪锡德
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2004-06-28
Filing date: 2005-06-28
Publication date: 2006-02-01
Anticipated expiration: 2025-06-28
Also published as: KR100667317B1; CN100485541C; KR20060048088A

Abstract

A kind of imaging device comprises: with a plurality of image carriers of predefined procedure setting; Contact an intermediate transfer medium of running with in described a plurality of image carriers each; With a plurality of backing rolls that are used to drive this intermediate transfer medium.Distance between the center of at least two image carriers be a backing roll girth positive integer doubly.

Description

The imaging device and the manufacture method of the image error that minimizing is caused by image carrier

Technical field

The present invention relates to a kind of driver element that is used for imaging device, and the color image forming apparatus with this driver element, and the manufacture method with imaging device of this driver element.

Background technology

Usually, imaging device is divided into forming monochrome image device and color image forming apparatus.The forming monochrome image device only utilizes monochromatic developer to form black white image, and color image forming apparatus utilizes color developer, forms coloured image as pinkish red, green grass or young crops, Huang and black.

As everyone knows, electrophotographic imaging forming apparatus utilizes exposure device to pass through laser beam flying is formed electrostatic latent image on organic photoconductor (OPC), wherein makes organic photoconductor have the electromotive force of predetermined level by charhing unit.Transfer printing becomes visible image on the printer paper of electrostatic latent image through supplying with after the developer development.In color image forming apparatus, by utilizing color developer electrostatic latent image is developed on organic photoconductor, and the image of double exposure is transferred on intermediate transfer medium such as the intermediate transfer belt (1TB).Coloured image at double exposure on the intermediate transfer medium is transferred on the printer paper.Subsequently, this printer paper with coloured image is discharged from imaging device through behind a series of fixings.

Figure 1 shows that the structural drawing of conventional color image forming apparatus, it utilizes intermediate transfer medium to carry out two step transfer printing programs.With reference to Fig. 1, this color image forming apparatus comprises is with 12,13,14 and 15, four

organic photoconductors

16,17,18 of 11, four T1 rollers of 10, one backing rolls and 19, one T2 rollers 20, and a band driven roller 21.

Be attached with developer of all kinds on the electrostatic latent image zone of each in

organic photoconductor

16,17,18 and 19 corresponding to K (deceiving), C (green grass or young crops), M (magenta) and yellow (Y) look.These

T1 rollers

12,13,14 and 15 are mounted to corresponding with

organic photoconductor

16,17,18 and 19, be with 10

organic photoconductor

16,17,18 and 19 and

T1 roller

12,13,14 and 15 between.Therefore, being attached to the transfer printing effect of

organic photoconductor

16,17,18 and 19 lip-deep developers by

T1 roller

12,13,14 and 15 at first is transferred to on 10 the surface.Therein on the

organic photoconductor

16,17,18 and 19 separately the image of color be transferred at interval with preset time and be with on 10, therefore be transferred to the developer of all kinds on 10 and can carry out alignment (registration) double exposure and form final coloured image.Therefore, color developer double exposure and then form final coloured image on 10.Subsequently, between T2 roller 20 and band driven roller 21, carry out the secondary transfer printing process with the coloured image on 10.In addition, band driven roller 21 is with 10 with normal speed.

With 10 and

organic photoconductor

16,17,18 and 19 are consumable articles with limited operating life, need the cycle to change.

Transfer printing unit and common with predetermined the coupling the unit and provide the driver element of power to be installed in the imaging device with removably of the developing cell that comprises each

organic photoconductor

16,17,18 or 19 with 10 are provided.

When consumable articles such as transfer printing unit and developing cell were replaced, it was important carrying out the structure that couples the unit that driver element, transfer printing unit and developing cell relatively move.In other words, connecting transfer printing unit, to have identical turning axle with developing cell with driver element be important.Consider the so-called whole circular error (total runout) of losing between transfer printing unit and developing cell, realize that high-precision colored alignment is also very important.Because there is manufacturing tolerance in the driven roller of transfer printing unit on outer surface, so this is just more important.

Therein should integral body lose circular error and can be understood as and comprise a kind of like this phenomenon, promptly be with 10 with normal speed rotation, and because the external peripheral surface of the driven roller of this transfer printing unit exists manufacturing tolerance to cause that instantaneous speed of rotation changes.Whole lose circular error can influence developing cell in same period by with 10 developing cell.Therefore, adjust whole influence of losing circular error on the developing cell, thereby the quality that improves coloured image is important.

In addition, if the organic photoconductor or the periphery of driven roller are not to make desirable circle, their radius can change.Owing to the deviation on above-mentioned OPC roller and the driven roller makes coloured image partly be stretched or cuts off (cut), thus this class deviation can cause with on synthetic coloured image error appears.

Summary of the invention

Therefore, an object of the present invention is to provide a kind of roller that can control the orientation of intended radial displacement.

Second purpose of the present invention provides a kind of method of making the roller of the orientation that can control the intended radial displacement.

The 3rd purpose of the present invention provides a kind of improved driver element of imaging device, and it can control the image error that the radial error of backing roll because of band causes.

The 4th purpose of the present invention provides a kind of improved imaging device, and it can control the image error that causes because of a plurality of image carriers.

The 5th purpose of this aspect provides a kind of improved imaging device, and it can control the image error that causes because of a plurality of image carriers and band backing roll.

Above-mentioned aspect of the present invention and/or other features can realize that by a kind of roller is provided this roller comprises: comprising: a roll body that has radial displacement along peripheral direction; With a driven coupler of closing with a termination of this roll body, it is used for driving the coupler complementary fit with one of transmission driving force.This roll body has and is formed on a precalculated position to indicate the mark of radial displacement.

This driven coupler comprises location parts that are used for definite position that engages with this driving coupler.This roll body engages with this driven coupler, makes this positioning element keep a predetermined angular with respect to this mark.

The position that this mark preferably is provided with respect to the maximum radial displacement of this roll body becomes a predetermined angular.

According to an aspect of the present invention, a kind of image carrier that is used in the imaging device comprises: a drum body that has radial displacement along peripheral direction; With a driven coupler of closing with a termination of this roll body, I am used for the driving coupler complementary fit with the transmission driving force.This drum body has and is formed on the mark that a precalculated position is used to indicate radial displacement.

The position that this mark preferably is provided with respect to the maximum radial displacement becomes a predetermined angular.

This driven coupler preferably includes location parts that are used for definite position that engages with this driving coupler.This drum body engages with this driven coupler, makes this positioning element keep a predetermined angular with respect to this mark.

This driven coupler preferably includes a non-circular coupling access component, and these parts form with recessed or protruding mode and at one end go up, and engages with this driven coupler and accepts driving force.This positioning element extends from this coupling access component on this driven coupler radial direction.

According to another aspect of the present invention, a kind of method of making roller, this roller comprises along peripheral direction having a roll body of radial displacement and a driven coupler of closing with a termination of this roll body.This method may further comprise the steps: the position of the radial displacement of identification roll body; And the position according to identification is provided with the position of this driven coupler and should driven coupler engages with this roll body in described position.

The step of finding out the position with radial displacement preferably includes following step: by measuring an end of this roll body, find out the point of maximum radial displacement; And on this roll body, form mark, be used to indicate the point of the maximum radial displacement of being found out.

The step that engages this driven coupler preferably includes: should drive coupler and be assembled on this roll body, make the positioning element of this driven coupler keep a predetermined angular, and the relative position of the joint of this driven coupler and this driving coupler is determined with respect to the point of this maximum radial displacement.

The step that engages this driven coupler preferably includes following step: at one first this roll body of anchor clamps upper support, the point that makes the maximum radial displacement becomes predetermined angular location with respect to the reference coordinate axle; In this driven coupler of one second anchor clamps upper support, make this driven coupler become predetermined angular location with respect to the reference coordinate axle; And these first and second anchor clamps are close to each other, and should driven coupler engage with this roll body.

According to a further aspect in the invention, a kind of driver element of imaging device comprises: be used to drive a driven wheel and a driven wheel that is used to drive the supported roller with a plurality of image carriers of predefined procedure setting, this backing roll support belt turns round on a plurality of image carriers.Distance between at least two the rotation center in a plurality of driven wheels be one girth in this backing roll positive integer doubly.

In the distance between the rotation center of a plurality of driven wheels each preferably the girth of at least one in this backing roll positive integer doubly.

One in this backing roll can be a driven roller, and this driven roller engages with this driven wheel and accepts a driving force.

One in this backing roll can be the roller with radial displacement.

This driven wheel preferably include with respect to the direction of tape travel with predefined procedure be provided with first to the 4 wheel driven moving gear, first satisfies in the equation at least one to the 4 wheel driven moving gear:

(equation set 1)

L1＝l·Sd·(1±0.05)(l＝1，2，3，)......................1

L2＝m·Sd·(1±0.05)(m＝1，2，3，)......................2

L3＝n·Sd·(1±0.05)(n＝1，2，3，)......................3

L4＝o·Sd·(1±0.05)(o＝1，2，3，)......................4

L5＝p·Sd·(1±0.05)(p＝1，2，3，)......................5

L6＝q·Sd·(1±0.05)(q＝1，2，3，)......................6

Wherein, L1 is the distance between the center of first, second main drive gear,

L2 is the distance between the center of second, third driven wheel,

L3 is the 3rd, the distance between the center of 4 wheel driven moving gear,

L4 is the distance between the center of the first, the 3rd driven wheel,

L5 is first, the distance between the center of 4 wheel driven moving gear,

L6 is second, the distance between the center of 4 wheel driven moving gear and

Sd is the girth of a roller in this backing roll.

This driven wheel preferably is installed into and satisfies equatioies all in the equation set 1.

This driven wheel preferably is installed into and satisfies L1=L2=L3.

This driven wheel preferably is mounted to and satisfies L1=L2=L3, and L1, L2, L3 be Sd positive integer doubly.

The radius of this backing roll preferably equals the radius of this image carrier.

A plurality of driving coupler preferably are arranged on each the rotation center in a plurality of driven wheels, are used for engaging with each of a plurality of image carriers and transmit driving force.

This driving coupler comprises: a coupling access component, be constructed with the end that is arranged on each image carrier on the corresponding noncircular cross section of each driven coupler; With location parts, be arranged on a side of this coupling access component, with the position of determining to engage, make this driving coupler engage this driven coupler with fixing attitude.

This coupling access component can be from a concave end of this coupler form noncircular cross section structure couple recess, and this positioning element can be from the recess of the recessed predetermined depth in inboard of this coupling access component.

This driven coupler comprises from an end one to the rotation center projection, and has an axis hole and this to be coupling in this bottom surface that couples recess to close.

This coupling access component can be from an end and extends the protuberance that couples that forms the noncircular cross section structure, and this positioning element can be the protuberance that extends from this outside that couples protuberance.

According to another aspect of the present invention, a kind of imaging device comprises: with a plurality of image carriers of predefined procedure setting; Contact the intermediate transfer medium of running with in a plurality of image carriers each; With a plurality of backing rolls that are used to drive this intermediate transfer medium.Distance between the rotation center of at least two image carriers be at least one backing roll girth positive integer doubly.

This image carrier preferably includes first to the 4th image carrier that the direction with respect to the running of this intermediate transfer medium is provided with predefined procedure, and first to the 4th image carrier preferably satisfies at least one in the equation:

(equation set 1)

L1＝l·Sd·(1±0.05)(l＝1，2，3，)....................1

L2＝m·Sd·(1±0.05)(m＝1，2，3，)....................2

L3＝n·Sd·(1±0.05)(n＝1，2，3，)....................3

L4＝o·Sd·(1±0.05)(o＝1，2，3，)....................4

L5＝p·Sd·(1±0.05)(p＝1，2，3，)....................5

L6＝q·Sd·(1±0.05)(q＝1，2，3，)....................6

L2 is the distance between the center of second, third driven wheel,

L3 is the 3rd, the distance between the center of 4 wheel driven moving gear,

L4 is the distance between the center of the first, the 3rd driven wheel,

L5 is first, the distance between the center of 4 wheel driven moving gear,

L6 is second, the distance between the center of 4 wheel driven moving gear and

Sd is the girth of a roller in this backing roll.

This image carrier preferably is installed into and satisfies equatioies all in the equation set 1.

This image carrier preferably is installed into and satisfies L1=L2=L3.

This image carrier preferably is installed into and satisfies L1=L2=L3, and L1, L2, L3 be Sd positive integer doubly.

Described a plurality of backing roll preferably includes a driven roller, is used for along with transmitting the driving force rotation on it and drive this intermediate transfer medium, and driven rotation and support an idler roller of this intermediate transfer medium, and Sd is the girth of this driven roller.

One driver element preferably is set is used to drive this image carrier and this backing roll.

This driver element preferably includes: one first driver element is used for driving simultaneously a plurality of image carriers; With one second driver element, be used for of a plurality of backing rolls of individual drive.

This first driver element preferably includes: a plurality of driven wheels, and it is configured to corresponding with in a plurality of image carriers each, and the rotation that is relative to each other; With one first CD-ROM drive motor, be used to provide driving force to drive a plurality of driven wheels simultaneously.

This second driver element comprises: one second CD-ROM drive motor; With with backing roll in one engage and by a driven wheel of second drive motor.

Each driving gear and each image carrier preferably comprise that in their respective end portions one drives a coupler and a driven coupler that is used for this driving coupler of complementary fit.

This driving and driven coupler comprise in their end: the coupling access component of being arranged to noncircular cross section and cooperation complimentary to one another; Positioning element extends into a predetermined configuration from a side of each coupling access component, drives and the attitude of the joint of driven coupler to determine this.

Image carrier has the radial displacement of change in radius on peripheral direction, and has the interval A1 of the maximum radial displacement of pre-position, A2, and A3 and A4, and first to the 4th image carrier is installed into one that satisfies in the equation:

(equation set 2):

{2π·l+(α2-α1)}·Ro·(1±0.05)＝L1，(l＝0，1，2，...)，(Ro＝Ro1＝Ro2)....①

{2π·m+(α3-α1)}·Ro·(1±0.05)＝L1+L2，(m＝0，1，2，...)，(Ro＝Ro1＝Ro3)......................................................................②

{2π·n+(α4-α1)}·Ro·(1±0.05)＝L1+L2+L3，(n＝0，1，2，...)，(Ro＝Ro1＝Ro4)....................................................................③

Wherein, α 1 angle on the reverse rotation direction of described first image carrier, measuring to the center of described interval A1 from the position that the transfer printing of described first image carrier begins,

α 2 on the reverse rotation direction of described second image carrier from position that the transfer printing of described second image carrier begins to the measured angle in the center of described interval A2,

α 3 on the reverse rotation direction of described the 3rd image carrier from position that the transfer printing of described the 3rd image carrier begins to the measured angle in the center of described interval A3,

α 4 on the reverse rotation direction of described the 4th image carrier from position that the transfer printing of described the 4th image carrier begins to the measured angle in the center of described interval A4, and

Ro1, Ro2, Ro3 and Ro4 are the radiuses of described first to the 4th image carrier.

This image carrier preferably satisfies L1=L2=L3.

This image carrier preferably satisfies L1=L2=L3, and L1, and L2 and L3 are the integral multiples of Sd.

Driver element preferably is set is used to drive image carrier and backing roll, and each image carrier at one end has driven coupler, this driven coupler engages with driver element and accepts driving force.

Each driven coupler preferably includes location parts, is used for determining that the position that engages with respect to this driver element and this driven coupler are joined so makes the interval A1 of each image carrier, A2, and A3 and A4 and this positioning element form a predetermined angular.

This driver element preferably includes: one first driver element is used for driving simultaneously first to the 4th image carrier; With one second driver element, be used for this backing roll of individual drive.

This first driver element preferably includes: a plurality of driven wheels, be arranged to correspondingly respectively with a plurality of image carriers, and and be relative to each other and rotate together, and each driven wheel has a driven coupler to engage with this driven coupler at one end; With one first CD-ROM drive motor, be used to provide driving force to drive a plurality of driven wheels simultaneously.

This first and second image carrier preferably is installed into first equation that satisfies among the equation 2-1, and satisfies α 1=α 2.

This first and the 3rd image carrier preferably is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 3.

This first and the 4th image carrier is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 4.

This first to the 4th image carrier is installed into all equatioies that satisfy among the equation 2-1, and satisfies α 1=α 2=α 3=α 4.

This image carrier has the radial displacement of change in radius on peripheral direction, and has an interval A1 of the maximum radial displacement of pre-position, A2, A3 and A4, and in first to the 4th image carrier at least two are installed into one that satisfies in the equation:

(equation set 3):

{2π·l+(α2-α1)}·Ro·(1±0.05)＝L1，(l＝0，1，2，...)，(Ro＝Ro1＝Ro2)...①

{2π·m+(α3-α2)}·Ro·(1±0.05)＝L2，(m＝0，1，2，...)，(Ro＝Ro2＝Ro3)...........................................................................②

{2π·n+(α4-α3)}·Ro·(1±0.05)＝L3，(n＝0，1，2，...)，(Ro＝Ro3＝Ro4)...........................................................................③

This image carrier preferably satisfies L1=L2=L3.

This image carrier preferably is installed into all equatioies that satisfy in the equation set 3, and satisfies α 1=α 2=α 3=α 4.

Each image carrier all has the radial displacement of change in radius on peripheral direction, and A has the maximum radial displacement in the pre-position at interval, wherein, when a radial displacement in the backing roll with change in radius on peripheral direction, and B has the maximum radial displacement at interval, and with reference to based on the predetermined coordinate system of the rotation center of this backing roll and this image bearing roller (X, Y), this image carrier and this backing roll are installed in the equation below satisfying:

(equation set 3)

Rd·θd＝(2π·l+θox)·Rox·(1±0.05)(l＝1，2，3，...)，(x＝1，2，3，...)，Rd＝z·Rox，(z＝2，3，4，5，...).....................................................①

Rd·θd＝Rox·θox·(1±0.05)，Rd＝θox，(x＝1，2，3，...)...................②

(2π·h+θd)·Rd＝Rox·θox·(1±0.05)，(h＝1，2，3，...)，(x＝1，2，3，...)，Rox＝k·Rd，(k＝2，3，4，5，...)......................................................③

Wherein, θ d be along (X, Y) coordinate system+angle at the center of the interval B of X-axis on the reverse rotation direction of described backing roll,

θ ox is on the reverse rotation direction of described image carrier, from (x) the individual image carrier on the rotation direction of described intermediate transfer medium+Y-axis is to the measured angle in center of A at interval,

Rox be described (x) individual image carrier radius and

Rd is the radius of described backing roll.

This+X preferably is defined as the rotation direction of parallel this intermediate transfer medium, makes that when on being centered close to of this interval B+X-axis, the velocity variations of this intermediate transfer medium reaches maximal value.

When the radius of this image carrier of radius ratio of this backing roll is big, and when being its integral multiple, this integer can be 2 or bigger, and this image carrier and this backing roll just are set to satisfy first equation of equation set 3.

When the radius of this image carrier equaled the radius of this backing roll, this image carrier and this backing roll just were set to satisfy second equation of equation set 3.

When the radius of this backing roll of radius ratio of this image carrier is big, and when being its integral multiple, this integer can be 2 or bigger, and this image carrier and this backing roll just are set to satisfy the 3rd equation of equation set 3.

One first driver element preferably is set, is used for driving simultaneously image carrier, and one second driver element preferably is set, be used for driving of backing roll.

Each image carrier preferably includes a drum body, and with the driven coupler that a termination of this drum body is closed, this driven coupler is connected with this first driver element and accepts driving force.

The bulging body of each image carrier preferably has a mark that is used to indicate maximum radial displacement interval A.

The driven coupler of each image carrier preferably includes location parts, is used for determining its position that engages with first driver element, and this image carrier is joined so with this driven coupler and makes this positioning element setting and this be marked as predetermined angular.

Each backing roll preferably includes a roll body, and a driven coupler of closing with a termination of this roll body, and this driven coupler is used to accept the driving force from second driver element.

The driven coupler of each backing roll preferably includes location parts, be used for determining its position that engages with second driver element, and this roll body is preferably becoming the predetermined angular place to have the sign mark of B at interval with positioning element.

This image carrier preferably has identical radius.

This image carrier preferably is configured to satisfy L1=L2=L3.

In this image carrier each preferably all has the radial displacement of change in radius, and A has the maximum radial displacement in the pre-position at interval, wherein, radial displacement in backing roll with change in radius, and B has the maximum radial displacement at interval, and with reference to based on the predetermined coordinate system of the rotation center of this backing roll and this image bearing roller (X, in the time of Y), this image carrier and this backing roll are installed in the equation below satisfying:

(equation set 3)

Rd·θd＝(2π·l+θox)·Rox·(1±0.05)(l＝1，2，3，...)，(x＝1，2，3，...)，Rd＝z·Rox，(z＝2，3，4，5，...)....................................................①

Rd·θd＝Rox·θox·(1±0.05)，Rd＝θox，(x＝1，2，3，...)..................②

(2π·h+θd)·Rd＝Rox·θox·(1±0.05)，(h＝1，2，3，...)，(x＝1，2，3，...)，Rox＝k·Rd，(k＝2，3，4，5，...).....................................................③

Rox be described (x) individual image carrier radius and

Rd is the radius of described backing roll.

When the radius of this image carrier of radius ratio of this backing roll is big, and when being its integral multiple, this integer can be 2 or bigger, and this image carrier and this backing roll preferably are set to satisfy first equation of equation set 3.

When the radius of this image carrier equaled the radius of this backing roll, this image carrier and this backing roll preferably were set to satisfy second equation of equation set 3.

When the radius of this backing roll of radius ratio of this image carrier is big, and when being its integral multiple, this integer can be 2 or bigger, and this image carrier and this backing roll preferably are set to satisfy the 3rd equation of equation set 3.

This image carrier preferably is configured to satisfy L1=L2=L3.

This image carrier preferably is configured to satisfy L1=L2=L3, and L1, L2 and L3 be Sd positive integer doubly.

One first driver element preferably is set, is used to drive image carrier and backing roll, and in this image carrier each preferably all has a driven coupler at one end, this driven coupler is connected with this driver element and accepts driving force.

Each driven coupler preferably includes location parts, be used for definite position that engages with this driver element, and this driven coupler is joined so and makes the interval A1 of each image carrier, and A2, A3 and A4 are formed in and become a predetermined angular place with this positioning element.

This driver element comprises: one first driver element is used for driving simultaneously first to the 4th image carrier; With one second driver element, be used for this backing roll of individual drive.

This first driver element comprises: a plurality of driven wheels, be arranged to correspondingly respectively with a plurality of image carriers, and and be relative to each other and rotate together, and each driven wheel has a driven coupler on the one end, engage with this driven coupler; With one first CD-ROM drive motor, be used to provide driving force to drive a plurality of driven wheels simultaneously.

This first and the 4th image carrier preferably is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 4.

According to another aspect of the present invention, a kind of imaging device comprises: with a plurality of image carriers that predefined procedure is provided with, it has along the radial displacement on its peripheral direction, and has the interval A of maximum radial displacement; Contact the intermediate transfer medium of running with in a plurality of image carriers each; With a plurality of backing rolls that are used to guide this intermediate transfer medium running and support this intermediate transfer medium, and this backing roll has the radial displacement of change in radius, and has an interval B of maximum radial displacement, wherein, reference is based on the predetermined coordinate system (X of the rotation center of this backing roll and this image bearing roller, Y), this image carrier and this backing roll are installed into one that satisfies in the following equation set 3:

(equation set 3)

Rd·θd＝(2π·l+θox)·Rox·(1±0.05)(l＝1，2，3，...)，(x＝1，2，3，...)，Rd＝z·Rox，(z＝2，3，4，5，...).......................................................................①

Rd·θd＝Rox·θox·(1±0.05)，Rd＝θox，(x＝1，2，3，..)............................②

(2π·h+θd)·Rd＝Rox·θox·(1±0.05)，(h＝1，2，3，...)，(x＝1，2，3，...)，Rox＝k·Rd，(k＝2，3，4，5，...)..............................................................③

Rox be described (x) individual image carrier radius and

Rd is the radius of described backing roll.

One driver element preferably is set, is used to drive image carrier and backing roll, and in this image carrier each all has a driven coupler at one end, this driven coupler is connected with this driver element and accepts driving force.

Each driven coupler preferably includes location parts, be used for determining its position that engages with this driver element, and this driven coupler preferably is joined so and makes the interval A1 of each image carrier, and A2, A3 and A4 are formed in and become a predetermined angular place with this positioning element.

This first driver element preferably includes: a plurality of driven wheels, be arranged to corresponding with in a plurality of image carriers each, and the rotation that is relative to each other, and each driven wheel has a driven coupler on the one end, engage with this driven coupler; With one first CD-ROM drive motor, be used to provide driving force to drive a plurality of driven wheels simultaneously.

This second driver element preferably includes: driven wheel, be arranged to correspondingly with a plurality of backing rolls, and and each driven wheel has one and drives coupler on the one end, be used for engaging with the driven coupler of the end that is arranged on each backing roll; With one second CD-ROM drive motor, be used to drive driven wheel.

Description of drawings

In conjunction with the accompanying drawings and according to a particular embodiment of the invention, above-mentioned aspect of the present invention and feature will become more obvious.

Fig. 1 is the structural representation of conventional color image forming apparatus;

Fig. 2 is the structural representation of color image forming apparatus according to an embodiment of the invention;

Fig. 3 is the skeleton view of driver element shown in Figure 2;

Fig. 4 A is the skeleton view of the image carrier taken apart;

Fig. 4 B is the skeleton view of driving coupler shown in Figure 3;

Fig. 4 C is the skeleton view of driven roller shown in Figure 2;

Fig. 5 is the image carrier of Fig. 4 A according to another embodiment of the present invention and the skeleton view that drives coupler;

Fig. 6 is the synoptic diagram of the radial displacement that causes because of the manufacturing tolerance of image carrier among Fig. 2 and driven roller;

Fig. 7 A is the synoptic diagram of the process of the end of the image carrier of monitoring Fig. 4 A;

Fig. 7 B is the synoptic diagram of process of the image carrier of installation diagram 4A;

Fig. 8 A is the structural representation according to the imaging device of first embodiment of the invention;

Fig. 8 B and 8C are under the state of Fig. 8 A because the curve map of the image error that the manufacturing tolerance of the radius of driven roller causes;

Fig. 9 A is the structural representation of the imaging device of routine;

The curve map of the image error that Fig. 9 B causes for the manufacturing tolerance of the radius of the driven roller of the imaging device shown in Fig. 9 A;

Figure 10 A is the structural representation according to the imaging device of second embodiment of the invention;

Figure 10 B is the curve map of the image error that the manufacturing tolerance of the radius of driven roller causes under the state of Figure 10 A;

Figure 11 A is the structural representation of another conventional imaging device;

Figure 11 B is the curve map of the image error that the manufacturing tolerance of the radius of driven roller causes under the state of Figure 11 A;

Figure 12 A is the structural representation according to the imaging device of third embodiment of the invention;

Figure 12 B is the curve map of the image error that the manufacturing tolerance of the radius of driven roller causes under the state of Figure 12 A;

Figure 13 is the structural representation of the major part of conventional imaging device;

Figure 14 A-Figure 14 D causes the synoptic diagram of image error for radial displacement is arranged because of image carrier;

The synoptic diagram that the image error that Figure 14 E causes for the radial displacement because of each image carrier is overlapping;

Figure 15 A is for there being the structural representation of conventional imaging device of the image carrier of radial displacement in use;

Figure 15 B is the curve map of the image error that causes because of the image carrier among Figure 15 A;

Figure 16 A-16D is the structural representation of the imaging device of third embodiment of the invention;

Figure 17 A is for being provided with the skeleton view of the anchor clamps that image carrier is installed according to the embodiment of the invention;

Figure 17 B is for being provided with the skeleton view of another example of the anchor clamps that image carrier is installed according to the embodiment of the invention;

Figure 18 A is the driven roller synoptic diagram bigger than image carrier;

The curve map of the image error that Figure 18 B causes for driven roller and image carrier under the state of Figure 18 A;

Figure 18 C is the structural representation of the imaging device of fourth embodiment of the invention;

The curve map of the image error that Figure 18 D causes for driven roller and image carrier under the state of Figure 18 C;

Figure 19 A is the illustrative diagram of the radius of driven roller and image carrier when identical;

Figure 19 B is the curve map of the image error that causes at state hypograph supporting body and the driven roller of Figure 19 A;

Figure 19 C is the structural representation of the imaging device of fifth embodiment of the invention;

The curve map of the image error that Figure 19 D causes for driven roller and image carrier under the state of Figure 19 C;

Figure 20 A is the radius of the image carrier structural representation during greater than the radius of driven roller;

The curve map of the image error that Figure 20 B causes for driven roller and image carrier under the state of Figure 20 A;

Figure 20 C is the structural representation of the imaging device of sixth embodiment of the invention;

The curve map of the image error that Figure 20 D causes for driven roller and image carrier under the state of Figure 20 C;

Figure 21 A is the structural representation of the imaging device of seventh embodiment of the invention;

Figure 21 B is the synoptic diagram of the image error that driven roller causes under the state of Figure 21 A;

Figure 21 C is the synoptic diagram of the image error that causes at the state hypograph supporting body of Figure 21 A;

The overlapping synoptic diagram of image error that Figure 21 D causes for state hypograph supporting body and driven roller at Figure 21 A;

Figure 22 A is the structural representation of the imaging device of eighth embodiment of the invention;

Figure 22 B is the synoptic diagram of the image error that driven roller causes under the state of Figure 22 A;

Figure 22 C is the synoptic diagram of the image error that causes at the state hypograph supporting body of Figure 22 A;

The overlapping synoptic diagram of image error that Figure 22 D causes for state hypograph supporting body and driven roller at Figure 22 A;

Figure 23 A is the structural representation of the imaging device of ninth embodiment of the invention;

Figure 23 B is the synoptic diagram of the image error that driven roller causes under the state of Figure 23 A;

Figure 23 C is the synoptic diagram of the image error that causes at the state hypograph supporting body of Figure 23 A;

The overlapping synoptic diagram of image error that Figure 23 D causes for state hypograph supporting body and driven roller at Figure 23 A.

All in the accompanying drawing, similar reference marker is represented similar element characteristics and structure.

Embodiment

Specific embodiments of the invention are described in detail with reference to the accompanying drawings.

The item that limits in description is used to help complete understanding the present invention such as detailed structure and element.To those skilled in the art, under the situation that does not deviate from the spirit and scope of the present invention, can carry out each various variants and modifications to described exemplary embodiment.In addition, for the purpose of clear and concise, known function and structure are not elaborated.

With reference to Fig. 2, imaging device according to an embodiment of the invention comprises a plurality of

rotation rollers

30,40,50,60, that is arranged to contact with a plurality of

rotation rollers

30,40,50,60 running is with 70, a plurality of supports this with 70 a

backing roll

80,91 and a driver element 100.

In embodiment illustrated in fig. 2, a plurality of

rotation rollers

30,40,50,60 are illustrated as organic photoconductor (OPC), and it is used to be with on 70 to this with certain each color image of order transfer printing.More specifically, in the description of the specific embodiment of the invention hereinafter, it is interpreted as four rollers, that is to say, four

OPC

30,40,50,60 are disclosed, its mode with double exposure is transferred to each coloured image separately to be with on 70, and coloured image generally includes black (K), blue or green (C), pinkish red (M) and yellow (Y) color image.

In addition, in the specific example of specific embodiments of the invention, along with 70 rotation direction,

organic photoconductor OPC

30,40,50,60 separately transfer printing sequentially black, blue or green, pinkish red double exposure becomes coloured image (these

organic photoconductors OPC

30,40,50,60 is rotation in a clockwise direction in this example) on 70 to being with yellow color image.

Be understandable that following characteristics of the present invention can be applicable to other situation equally, as be less than or during more than four

organic photoconductor OPC

30,40,50,60 when using.Should be understood that can be different with said sequence order along each

organic photoconductor OPC

30,40,50,60 being set with 70 rotation direction.

The developing apparatus 26,27,28,29 corresponding with shades of colour be arranged on

organic photoconductor OPC

30,40,50,60 near, the preferred setting thereunder is so that form versicolor image on the periphery of

organic photoconductor OPC

30,40,50,60.Any suitable general known configurations can both be applied on the developing apparatus 26,27,28,29, and we should understand the structure that the present invention is not limited to the developing apparatus 26,27,28,29 of example shown in this embodiment.

Be with 70 to support with running in a predetermined direction by driven roller 80, backing roll 91 and a plurality of T1 roller 93.Drive running and receive versicolor image on the

OPC

30,40,50,60 by the revolving forces of driven roller 80 with 70 in the mode of double exposure.Thereby, form full-colour image, be transferred to then with 70 and T2 roller 95 between on the print media 97 that passes through.Driven roller 80 is connected on the driver element 100, and accepts drive force band 70 from driver element 100.This backing roll 91 can be resiliently biased towards being with 70, and making can be with the running of constant-tension support belt 70.

With reference to Fig. 2 and Fig. 3, driver element 100 comprises framework 110, is arranged on this framework 110 and drives first drive part 101 of

OPC

30,40,50,60 and drive second drive part 103 of driven roller 80.

This framework 110 comprises a front baffle 111 and an afterframe 112, and both are parallel to each other to couple.

First drive part 101 comprises first CD-ROM drive motor 121 that is arranged on this framework 110; First main drive gear (main gear) is promptly corresponding to versicolor first to the 4th the driven wheel 123,124,125,126 that is used for of

OPC

30,40,50,60; And first drive coupler 133,134,135,136, and it is separately positioned on first to the turning axle of 4 wheel driven moving gear 123,124,125,126.First is provided at predetermined intervals to 4 wheel driven moving gear 123,124,125,126, and is arranged on rotation between framework 111 and 112.Mark 122 expression shaft gears among Fig. 2, it is arranged at the driving shaft of CD-ROM drive motor 121, and drives driven wheel 124,125 separately.In addition, Reference numeral 127 expression idling gears, its mobile driven wheel 123,124,125,126 in ground that is relative to each other.A CD-ROM drive motor 121 is arranged on four driven wheels, 123,124,125,126 approximate position intermediate to rotate driven wheel 123,124,125,126 in identical direction.

Corresponding to every kind of color first to the moving coupler the 133,134,135, the 136th of 4 wheel driven, be rotatably connected with driven wheel 123,124,125,126.First is configured to engage with the transmission driving force with driven coupler on the end of each

organic photoconductor OPC

30,40,50,60 to the moving coupler 133,134,135,136 of 4 wheel driven.Driving coupler 133,134,135,136 and driven coupler can introduce in the back in detail.

Second drive part 103 comprises second CD-ROM drive motor 141 that is installed on the framework 110; Second main drive gear promptly rotatably is arranged between

framework

111 and 112 and by the 5th driven wheel 143 of second CD-ROM drive motor, 141 driven in rotation; With the 5th driving coupler 145, it is arranged on the turning axle of the 5th driven wheel 143.The 5th driven wheel 143 preferably is driven to 4 wheel driven moving gear 123,124,125,126 dividually with first.The 5th drives coupler 145 together rotates with the 5th driven wheel 143, and is configured to the driven coupler complimentary engagement with driven roller 80, with the transmission driving force.In this specific embodiment, first to the 5th all driving coupler 133,134,135,136 and 145 all is illustrated as has the identical structure that couples.Therefore, other structures of

OPC

30,40,50,60, the structure of especially driven coupler can be understood that it is identical in this embodiment.Therefore, for simplicity's sake, only drive coupler 133 and be described as their representative example with K look OPC 30 and first.Same, first description that drives coupler 133 can be replaced with corresponding to the 5th of driven roller 80 and drive coupler 145.

Simultaneously, as consumable articles, organic photoconductor OPC is limited 30,40,50,60 serviceable lifes, promptly scraps when using above behind the

pre-determined number.OPC

30,40,50,60 can be installed separately, or optionally, and is integrally formed and be removably mounted on the imaging device main body 25 with developing apparatus 26,27,28,29.

Organic photoconductor OPC

30,40,50,60 can be rotated by the driving force that driver element 100

transmits.OPC

30,40,50,60 engages separately has driven being driven to couple structure, so that move coupler 133,134,135,136 complementary fit to 4 wheel driven with first, therefore, when being installed on the imaging device main body 25, organic

optical conductor OPC

30,40,50,60 accepts driving force from driver element 100.Because each

organic photoconductor OPC

30,40,50,60 can adopt identical structure, is example with the K look OPC 30 that is used to form the K color image shown in Fig. 4 A only hereinafter, carries out representative illustration.

With reference to Fig. 4 A, black organic photoconductor (here after all abbreviate as " OPC ") 30 comprise a cylindrical drums body and with the driven coupler 33 of an engaged at end of this drum body.This drum body can be made by metal material, as uses stainless steel, also can be configured to the cylinder that all open at two ends.On the periphery of this drum body the coating or apply a photoelectric conductor layer.

One end of this driven coupler 33 is ends that are press fitted into this drum body.On the other end, this driven coupler 33 disposes the coupling access component 33a of a noncircular cross section, and projection is a location parts 33b of reservation shape from the side of this coupling access component 33a.This coupling access component 33a drives coupler 133 (as Fig. 4 B) with first of driver element 100 and cooperates to transmit driving force.This positioning element 33b determines the position of this driven coupler 33, just, determines OPC 30 with respect to the angle that couples that drives coupler 133.The structure identical with the structure of the first driven coupler 33 also may be used on

other OPC

40,50,60, and therefore, only the first driven coupler 33 with K look OPC 30 is described below as representative illustration.

The first driven coupler 33 preferably also comprises along the axle 33c of the turning axle projection of coupling access component 33a.This 33c couples mutually with the first axis hole 133c (Fig. 4 B) that drives coupler 133, and guiding first drives coupler 133 and the first driven coupler 33 cooperates coaxially to each other.

First drives coupler 133 preferably also comprises from the coupling access component 133a of the end depression of non-circular structure one a positioning element 133b and an axis hole 133c who caves in from the inboard of coupling access component 133a.This coupling access component 133a is configured to the coupling access component 33a corresponding shape with driven coupler 33, and positioning element 133b is configured to the positioning element 33b corresponding shape with driven coupler 33.

Shown in Fig. 4 C, driven roller 80 comprises a roll body 81, with a driven coupler 83 that couples mutually with the end of this roll body 81.This driven coupler 83 can have the structure identical as the driven coupler 33 of OPC 30 among Fig. 4 A.More specifically, this driven coupler 83 comprises coupling access component 83a and the positioning element 83b outstanding from this coupling access component 83a side of a noncircular cross section.The driven coupler 83 of this driven roller 80 is couple to the 5th as shown in Figure 3 and drives on the coupler 145.Because driven coupler 83 has the structure roughly the same with the driven coupler 33 shown in Fig. 4 A, the 5th drive coupler 145 can as with drive the first driving coupler, the 133 essentially identical structures that coupler 30 engages.Therefore, replace about the 5th first description that drives coupler 133 that drives the available Fig. 4 B of description of coupler 145.

The roll body 81 of driven roller 80 has predetermined radii Rd, so its girth Sd=2 π Rd.The girth of driven roller 80 " Sd " can be identical or different with the girth of

OPC

30,40,50,60, and the operation of every kind of situation and influence will be described in detail in the back.

First moves coupler 133,134,135,136 to 4 wheel driven preferably constructs in relative mode with driven coupler 33.More specifically, as shown in Figure 5, driven coupler 233 is formed on the end of roll body 231 of OPC233, and driven coupler 233 preferably has the non-circular coupling access component 234 of depression, and the positioning element 235 that extends from coupling access component 234.In this case, this driven coupler 330 corresponding with the driven coupler 233 of OPC230 as shown in Figure 5, can have from the coupling access component 331 of an end bosses of non-circular structure with from the positioning element 332 of a side projection of this coupling access component 331.This positioning element 332 matches with positioning element 235 complementations of this driven coupler 233.This driven coupler 233 can have an axis hole 236, and this driving coupler 330 have one with these axis hole 236 complementary fit the axle 233.

In other words, this driven coupler 233 can form in recessed mode in the end of this OPC 30, and the end corresponding to driven coupler 233 of driving coupler 330 is formed by the mode with projection.The example of Fig. 5 can be applied to all

OPC

30,40,50,60 and all first on the moving coupler 133,134,135,136 of 4 wheel driven.

Although do not illustrate, the structure of coupler as shown in Figure 5 also may be used on driven roller 80 and the 5th and drives on the coupler 145.In addition, although be not described in detail, various coupler structures also may be used on the backing roll 91.

Simultaneously, the roll body available metal mold treatment of

roller OPC

30,40,50,60 or driven roller 80 is produced in enormous quantities, as known.During roll body is produced in enormous quantities very part and parcel be that the roll body of production in enormous quantities can reach desirable circle along its periphery, because they always have tolerance or error aborning.This will be described in detail as example with organic photoconductor 30.

Exaggerative " the mistake circular error " that illustrates on the periphery that occurs in bulging body 31 of Fig. 6, i.e. the radial displacement of drum body in the predetermined space.More specifically, lose circular error and cause radial displacement δ o, promptly according to the radius of the variation of the swing circle of OPC 30.Radial displacement δ o is defined as in a swing circle of drum body, just in the swing circle of OPC 30, and the changing value of the minimum and maximum value of name (nominal) radius of expressing with sinusoidal curve.In this specific embodiment, the maximum radial displacement of roll body 31 is+δ o that the smallest radial displacement is-δ o.In addition, as shown in Figure 6, with reference to maximum radial displacement+δ o definition interval (interval) A, this influences image error at interval, and this will be described later.According to the size of radial displacement δ o, this is the range of A at interval.

As mentioned above, the operator need know this interval A so that control radial displacement δ o is to rousing any influence of body.For this reason, shown in Fig. 4 A, drum body 31 can identify underlined 31a so that the position of sign interval A.Mark 31a is labeled in the periphery of bulging body or goes up middle corresponding with interval (lnterval) A interior week.Can understand, mark 31a also can form apart from the center of this interval A and become predetermined angular, and still identifies the position of A at interval.

As mentioned above, by marker spacing A, the operator can regulate the positioning element 33b of driven coupler 33 and the relative orientation between the center of A at interval during driven coupler 33 with respect to the assembling of drum body 31.In other words, as Fig. 4 A and shown in Figure 6, in process of production, mark 31a preferably becomes the position of miter angle (+45 °) to be formed uniformly apart from the center of A at interval on the sense of rotation of OPC.Positioning element 33b and mark 31a align then, and drum body and driven coupler 33 are engaged with each other.All OPC are installed by the way, and the positioning element 33b of a plurality of rollers can be positioned at identical position with respect to interval A.

Can variety of methods allow positioning element 33b and mark 31a align.Example, shown in Fig. 7 A, each end of drum body can obtain by a camera (not shown), and the image that obtains can be by the screen display of predetermined watch-dog 200.Reference coordinate can be set on the screen 210, and (x is y) and with reference to full circle (reference complete clrcle) 211.By setting make this class reference coordinate (x y) is overlapped in reference to full circle 211, the center of the interval A of the image that is obtained, i.e. maximum radial displacement+δ o just can locate.Therefore, make it be 315 ° of location in the clockwise direction from+x axle by regulating maximum radial displacement+δ o, mark 31a preferred identity is on corresponding to the end of the locational bulging body 31 of axle+x or on the outside surface.

Next, shown in Fig. 7 B, the bulging body of bearing mark 31a is supported on first anchor clamps 241, mark 31a be positioned in reference frame (x, y)+the x axle on.Driven coupler 33 is supported by second anchor clamps 242, and, be provided with driven coupler 33 make positioning element 33b be positioned at reference frame (x ', y ')+x ' axle on.In this case, two anchor clamps 241,242 are positioned opposite to each other, make reference frame (x, y) and (x ', y ') aim at each other.Make two anchor clamps 230,240 close to each other by moving then, driven coupler 33 is engaged in a plurality of bulging bodies respectively, and therefore with identical relative orientation all coupler is installed simultaneously.Positioning element 33b can be positioned with respect to each center of rousing the interval A of body.Although with reference to an above-mentioned example, a plurality of OPC are installed simultaneously, we are to be understood that also this is also nonrestrictive, because OPC also can install separately with identical relative orientation respectively.

In another embodiment, can prepare a structure separately, wherein rousing body 31 is rotatably to be supported on first anchor clamps 241.In this case, by independent detecting devices such as mark sensor or monitor survey when drum body rotation tense marker 31a whether be positioned at+the x axle on.Therefore, be positioned at when mark 31a is detected+the x axle on the time, the drum body is stopped, and is coupled to driven coupler 33, makes positioning element 33b be orientated with respect to mark 31a.

This OPC 30 after being mounted in the above described manner, can be positioned in the center of A at interval, promptly is positioned on the position of-45 ° of positioning element 33b one-tenth.Therefore, consider, can reduce the image error that the deviation because of the radius of the OPC drum of interval A produces by the position of control OPC in assembling and when installing corresponding to the positioning element 33b location fact of A at interval.

Be installed on the driven coupler 33 with reference to the interval A with maximum radial displacement+δ o although rouse body as mentioned above, and the initial position of positioning element 33b also can be with reference to other at interval, as be spaced apart-δ o or δ o=0 be provided with.

As mentioned above, being appreciated that also that each interval among the

organic photoconductor OPC

40,50,60 of other colors is oriented to apart from positioning element 33b becomes-45 °.

Driven roller 80 is also lost circular error in installation process, and as shown in Figure 6, has maximum radial displacement+δ d on peripheral direction.Because of losing radial displacement+δ d that circular error produces, in the situation of OPC 30, be expressed as the sinusoidal curve in a swing circle of driven roller, and defined by minimum and maximum value.In this specific embodiment, the maximum radial displacement of driven roller 80 is+δ d that the smallest radial displacement is-δ d.Interval with maximum radial displacement+δ d is called B at interval.B influences the image error (being described in detail later) that produces because of driven roller 80 at interval, and can define in every way.In mode identical when OPC 30 is installed,, make driven roller 80 be oriented to make positioning element 83b can be positioned in apart from the center of B at interval to become on the position of the predetermined anglec of rotation by the installation of control roll body 81 and driven coupler 83 in installation process.In the example below, the positioning element 83a of driven coupler 83 is located on respect to the opposite direction of the sense of rotation of driven roller 80 apart from the center of B at interval to become on the position of 45 degree (promptly-45 °).

Simultaneously, the minimum and maximum radial displacement ± δ d of driven roller 80 can influence the speed with 70.In other words, tangential velocity reaches maximum Vdmax at the center of the interval of driven roller 80 B.Therefore, when interval B when being with 70 closely to contact with driven roller 80, thereby the position of applied force is aligned with each other, that is, when the direction of tangential velocity Vdmax is parallel to axle+y shown in as shown in Figure 6 the dotted line, be with 70 to turn round with maximal rate.Therefore, when the running speed of band changed, the coloured image on the

OPC

30,40,50,60 is transferred to when being with on 70 will distortion, make image be stretched, fuzzy or cut off.Therefore because the speed with 70 is periodically variable, periodically produce image error according to the swing circle of driven roller 80 on 70 being with in a swing circle.

The method of the image error that correction according to the present invention causes because of the radial displacement δ d of driven roller 80 hereinafter will be described.In the following description, suppose that

OPC

30,40,50,60 and backing roll 91 are not lose circular error, thus the radial displacement δ d=0 of

OPC

30,40,50,60.Therefore, suppose only have the radial displacement of driven roller 80 δ d influence to be transferred to the image on 70.For making the image error minimum, the influence of first step driven roller 80 will drop to minimum, and such example is described below.

At first, as the description of Fig. 6, when the rotation from positioning element 83b self-powered action roller 80 is represented as positive angular unit, suppose that the center of the interval B with maximum radial displacement+δ d of driven roller 80 is positioned in+45 with reference to previously.Be convenient and explain that angle+45 ° are the intervals of selecting at random.Driven roller 80 has predetermined radii Rd and girth Sd=2 π Rd.Setting has the driven roller 80 of radial displacement δ d, and

OPC

30,40,50,60 is configured to satisfy in six conditions of equation group 1, to reduce the image error of double exposure on 70:

(equation set 1)

L1＝l·Sd(1±0.05)(l＝1，2，3，...)...........(1)

L2＝m·Sd(1±0.05)(m＝1，2，3，...)...........(2)

L3＝n·Sd(1±0.05)(n＝1，2，3，...)...........(3)

L4＝o·Sd(1±0.05)(o＝1，2，3，...)...........(4)

L5＝p·Sd(1±0.05)(p＝1，2，3，...)...........(5)

L6＝q·Sd(1±0.05)(q＝1，2，3，...)...........(6)

With reference to Fig. 2, the center C 1 of first and second main drive gears 123,124, the distance between the C2 are L1, the center C 2 of driven wheel second and the 3rd driven wheel 124,125, the distance between the C3 are L2, the center C 3 of third and fourth driven wheel 125,126, the distance between the C4 are L3, the center C 1 of the first and the 3rd driven wheel 123,125, the distance between the C3 are L4, first and the center C 1 of 4 wheel driven moving gear 123,126, the distance between the C4 be L5, second and the center C 2 of 4 wheel driven moving gear 124,126, the distance between the C4 be L6.

Drive coupler 133,134,135,136 and be set to each driven wheel 123,124,125,126, and

OPC

30,40,50,60 rotatably engages with driving coupler 133,134,135,136.Therefore, center C 1, C2, C3, C4 aims at respectively with the rotation center of

OPC

30,40,50,60.Therefore, be appreciated that

OPC

30,40,50,60 is set to satisfy at least one in the equation set 1.Nature, L1 refers to the center C 1 of K look OPC 30 and C look OPC 40, the distance between the C2, L2 refers to the center C 2 of C look OPC 40 and M look OPC50, distance between the C3, L3 refers to the center C 3 of M look OPC50 and Y look OPC60, the distance between the C4, L4 refers to the center C 1 of K look OPC 30 and M look OPC50, distance between the C3, L5 refers to the center C 1 of K look OPC 30 and Y look OPC60, the distance between the C4, L6 refers to the center C 2 of C look OPC 40 and Y look OPC60, the distance between the C4.

Therefore, by being arranged to satisfy in the equation set 1 at least one as apparatus system, the image error that produces because of the deviation of the radius of driven roller 80 just is lowered.Figure 2 shows that preferred embodiment, wherein OPC30,40,50,60 is set to satisfy all equatioies in the equation set 1, wherein L1=L2=L3=Sd.

When

OPC

30,40,50,60 was set to not satisfy any one equation in the equation set 1, the image error with on 70 that the interval B of driven roller 80 causes frequently took place, and this can be described in detail later.In three examples below, mainly consider the radius R d of driven roller 80 and the radius R o of

OPC

30,40,50,60.

Shown in Fig. 8 A is first example, and wherein the radius of driven roller 80 is greater than the radius of

OPC roller

30,40,50,60, i.e. Rd＞Ro.In the example shown in Fig. 8 A, any one that

OPC

30,40,50,60 does not satisfy in the equation set 1.In other words, the center C 1 of

OPC

30,40,50,60, C2, C3, the distance between any two centers among the C4 is not the integral multiple of the girth Sd of driven roller 80.

With reference to Fig. 8 A, suppose beginning transfer printing K color image, interval B's is centrally located in along the position of the angle of axle+x one-tenth θ d (+135 °) at that time.Shown in Fig. 8 B, radial displacement δ d repeats with sinusoidal form according to the running distance with 70, and B occurs once at each swing circle of driven roller 80 at interval.With reference to Fig. 8 A, suppose the transfer printing of K color image from position f0, a swing circle of driven roller 80 is from being positioned at axle+x when last as position F0.Shown in Fig. 8 B, the image error Rke of the K color image that produces because of interval B is centered close to the position at a distance of Rd θ d with position F0.

When the length of the image of each image carrier transfer printing is become enough in short-term, in other words, when the position F2 that position F1 that finishes when the transfer printing of K color image and C color image begin transfer printing was aligned with each other, the interval of C color image transfer printing just can not be spaced apart B to be influenced.Therefore, the non-image error that causes because of interval B can not occur on the C color image.In other words, before being with 70 displacement 1Sd, the transfer printing of K color image is finished, and the C color image begins transfer printing.Because, be positioned at the position F3 that the transfer printing of C color image is finished and be with 70 before the F0 displacement Sd+Rd θ d of position, image error does not just take place in the C color image.

Next, suppose that M color image transfer position F4 is identical with position F3, the image error Rme of the M color image that produces because of interval B be located in position F4 at a distance of a preset distance place.Because distance L 4 is not the integral multiple of Sd, the position F4 that the transfer printing of M color image begins just behind a swing circle of driven roller 80, be with 80 from position f1 running apart from t1, f1 is second position that swing circle begins of driven roller 80.When the interval of each color image transfer printing was represented with cell picture zone P1, M look image error Rme appeared at the diverse location place that begins from the initial SL of cell picture zone P1.In other words, appear at two image error Rke among the P1 of cell picture zone, the distance between Rme is Rd θ d-t1.

According to identical principle, the position F5 that the transfer printing of M color image is finished, the position F6 that the transfer printing of Y color image begins is with 70 positions of running before the 2Sd, that is, and before driven roller 80 is finished second swing circle.Therefore, the image error Rye that produces because of interval B also appears at the Y color image.Wherein because Y color image transfer printing starting position F6 is positioned at the position that preset distance (t2) arranged with position f2, the center of Y image error Rye is located in the position at a distance of t2+Rd θ d with initial SL, and wherein position f2 is the position that driven roller 80 beginnings second swing circle begins.

Explain as top, when Rd＞Ro, have the influence that coloured image such as C color image are not subjected to the interval B of driven roller 80, because compare with bigger driven roller, the rotation of OPC roller is more frequent.Therefore, just do not need to consider colored OPC 40, but should aim among the image error Rke, the Rme that separate respectively, the Rye at least two, go up the frequency that image error takes place to be reduced in cell picture zone P1 corresponding to the netrual colour image error.In the following description, will describe and aim at black and magenta image error Rke, the method for Rme is as an example of the present invention.

In order to aim at two image error Rke, Rme, system will realize satisfying the 4th equation in the equation set 1.That is, the center C 1 of two

OPC

30,50, the distance between the C3 be set to L4=oSd (o=1,2,3......).For this reason, shown in the dotted line of Fig. 8 A, OPC50 is positioned at its center C3 and center C 1 apart from oSd place, wherein o=1.

Therefore, when system such as above-mentioned the setting, if the K color image begins transfer printing, the center of black image error Rke is located in the position at a distance of Rd θ d with initial SL.And as mentioned above, with reference to Fig. 8 B, the cyan image error does not appear.

Simultaneously, shown in Fig. 8 C,, that is to say that at the f1 place, position of driven roller 80 beginning second swing circle, magenta transfer printing starting position F4 is positioned at before the position F3 that the transfer printing of C color image finishes because the center C 3 of M look OPC50 is arranged on 1Sd place, position.Position F4 is identical in position f1.Therefore, the center of the magenta image error Rme that produces because of interval B is located in the position at a distance of Rd θ d with the initial SL of cell picture zone P1.Thereby black and magenta image error Rke, Rme just can be at identical location overlaps.Because in the last imaging of the coloured image that is printed, reduced the frequency that image error takes place, just can obtain high-quality printing.In this explanation, do not consider Y image error Rye.Y image error Rye occurs in as above and to be different from K and M image error Rke, the position of Rme with reference to Fig. 8 B.

Nature, Y image error Rye also can aim at other image error, satisfies the 4th in equation set 1 and C grade formula when setting up system, or satisfies the 4th and the 5th equation in the equation set 1 when setting up system.Can understand principle at an easy rate from the process of two kinds of image errors of above-mentioned aligning by condition double exposure K, M above satisfying, Y image error Rke, Rme, Rye.Therefore, for for purpose of brevity, just omit and describe in detail.

In this specific embodiment, the transfer printing of the

OPC

30,40,50,60 of every kind of color all is provided with at interval at random, and the point that coloured image begins and finishes also can be provided with at random for ease of explanation.Therefore, we are understood that the situation of above-mentioned concrete example can not be as limiting understanding.Satisfying under the condition of Rd＞Ro, various examples can, and the quantity of the image error in the cell picture zone can have various variations.As long as understand, no matter the quantity of image error what, should make that the error that has two images at least can be aligned with each other by satisfying at least one equation in the equation set 1, so that reduce the sum of the generation image error that the variation owing to the radius of driven roller 80 causes.

And although that describe among Fig. 8 A is variable o=1 in the 4th equation of equation set 1, this only is an example, therefore, and when variable o when being equal to or greater than 1 integer, also can obtain identical effect.

Second example in the first step will be described now.Shown in Fig. 9 A, the radius of at first describing any one equation ought not satisfy in the equation set 1 and driven roller equals the image error under the situation of radius (Rd=Ro) of OPC roller, describes subsequently by satisfying the method that at least one equation in the equation set 1 reduces image error.

At first with reference to 9A, suppose the K color image as+δ, promptly at interval the center of B relatively axle+x when position θ d (135 °), begin transfer printing.Shown in Fig. 9 B, the position at a distance of m1=Rd θ d with K color image transfer printing initial SL just takes place in the image error Rke that causes because of interval B.Promptly, the initial SL of K color image is from position F0, when initial SL arrives the F1 place, position (just finishing a cell picture based on supposing that driven roller 80 rotates a circle) that the transfer printing of K color image is finished, the center of the interval B of driven roller 80 is just the initial position shown in Fig. 9 A (that is, locating for 135 ° of axle X).Wherein because of the center C 1 of two OPC 30,40, the distance L 1 between the C2 is with 70 also will move t3 at interval again from position F1 than the long t3 of girth Sd of driven roller 80, and the C color image is just from position F2 beginning transfer printing.Suppose that driven roller 80 is 45 ° corresponding to the anglec of rotation of interval t3.In this case, because of the center of the error Rce of the C color image of interval B appears at the position at a distance of Rd θ d with position F1, but the fact that the actual initial SL that considers the C color image is F2, the center of image error Rce appear at the position at a distance of m2=Rd θ d-t3=Rd (θ d-45 °)=Rd90 ° with the initial SL of cell picture zone P1.Therefore, two image error Rke, the distance at Rce center and apart t3=Rd90 ° in cell picture zone.

In addition, because the center C 2 of C and M look

OPC

40,50, the distance L 2 between the C3 is than the long t3 of Sd, and when moving t3=Rd45 ° with the 70 position F3 from C color image transfer printing end, the M color image begins to be transferred to be with on 70.Position F4 with the starting point f2 of second swing circle of driven roller 80 position at a distance of 2t3.Therefore, when the center of considering the M look image error that produces because of interval B appears at 70 facts from the distance of position f2 running Rd θ d, the practical center of M look image error Rme just appear at from the initial SL of M color element image-region P1 position, d-2t3=m1-2Rd45 °=Rd of m3=Rd θ (θ d-90 °)=Rd45 ° at a distance of m3.Thereby M look image error Rme appears among the P1 of cell picture zone and black and cyan image error Rke, the different position of Rce.

With reference to Fig. 9 A, M look and Y look OPC50,60 center C 3, the distance between C4 is illustrated as L3=Sd+2t3.In this case, the starting point f3 of the 3rd swing circle of driven roller 80 was spaced apart 2t3 therebetween before the position F5 that the transfer printing of M color image finishes.Because two OPC50,60 distance are than Sd multi-compartment 2t3 also, the position that the Y color image begins transfer printing is from F6, and F6 has moved the position of 2t3 at interval with 70 again from position F5.Position F6 is with 70 to move at interval 4t3 from position f3.Therefore, the image error that produces because of interval B can not occur on the 3rd swing circle of driven roller, and Y image error Rye appears at the position f4 that begins with the 5th swing circle position at a distance of m1=Rd θ d.Y image error Rye is because position f4 is in Y color image transfer printing at interval.In this case, Y image error Rye occurs in F6 place, position, and this place is positioned at initial SL with cell picture zone P1 at a distance of the position of m4, m4=Sd+m1-4t3=Rd2 π+d-4Rd45 °=Rd of Rd θ (2 π-45 °).Because Y image error Rye appears at and other image errors Rke in the P1 of cell picture zone, Rce, Rme diverse location place, it will influence picture quality.As mentioned above, when Rd=Ro, at least one image error takes place in each transfer of color images.More specifically, although Fig. 9 A and 9B have described the example that all coloured images are transferred in the swing circle of OPC 30,40,50,60, also can be by in two swing circles of OPC 30,40,50,60, finishing a kind of transfer printing of color image.In this case, an image error takes place in the coloured image of each transfer printing.Therefore, just can be improved picture quality greatly by aiming at least two image errors that take place.

Be second example about the first step below, interpre(ta)tive system is set to satisfy the situation of all equatioies of equation set 1.With reference to Figure 10 A, system is set to the center C 1 of

OPC

30,40,50,60, C2, and C3, the distance between the C4 satisfies L1=L2=L3=Sd.Under these circumstances, when d=135 ° of the center of the interval of driven roller B edge+x axle rotation θ, suppose to begin to be transferred to and be with 70 at position F0K color image.If supposing a cell picture is that swing circle at

OPC

30,40,50,60 forms, the center C 1 of two

OPC

30,40, the distance L 1 between the C2 just is equivalent to the integral multiple of Sd, i.e. L1=1Sd.Therefore, shown in Figure 10 A and 10B, the position F0 that begins transfer printing from the K color image just begins the position f0 of first swing circle to the distance between the position f1 of driven roller 80 beginnings second swing circle corresponding to driven roller 80 to the distance the position F1 of K color image transfer printing end.Therefore, the center of K look image error Rke is located in the distance with 70 running m1=Rd θ d.

Next, because C color image transfer printing starting point F2 overlaps with position F1, and position f1 also overlaps with position F1, because B is created in the center of the C look image error Rce in the C color image just on the F1 of position at interval, that is, be positioned at the position at a distance of m1=Rd θ d with C color image initial SL.Thereby, K look and C look image error Rke, Rce is just at identical location overlap.

And because L1=L2=1Sd, M color image transfer printing starting point F4 and C color image transfer printing end position F3 be in identical position, also is the position of the some f2 that begins of the 3rd swing circle of driven roller 80.Because the M look image error Rme that produces by interval B be centered close to and the SL position at a distance of the position of m1=Rd θ d, F3 is identical with the position, K look and C look image error Rke, Rce just can be at identical location overlap.

In addition, because L1=L2=L3=Sd, Y color image transfer printing starting point F6 and M color image transfer printing end position F5 be in identical position, also is the position of the some f3 that begins of the 4th swing circle of driven roller 80.Therefore the center of the Y image error Rye that is produced by interval B is on F6, promptly is positioned at the position at a distance of m1=Rd θ d with the initial SL of cell picture zone P1.Because Y image error Rye occurs in K look, C look and M look image error Rke, Rce, the position overlapped place of Rme, the quantity of the image error on the P1 of cell picture zone just can reduce greatly, and resultant image quality is improved.

The 3rd embodiment about the first step is described below, wherein Rd＜Ro.

Shown in Figure 11 A is the system that works as Ro=2Rd.In the following description, the image that can suppose every kind of color is to finish in the rotation of

OPC

30,40,50,60.Therefore, in twice rotary course of the driven roller 80 among Figure 11 A and the 11B,

OPC

30,40,50,60 rotates once, and a cell picture is to form in the once rotation of

OPC

30,40,50,60.With reference to Figure 11 A, OPC30,40,50,60 center C 1 separately, C2, C3, C4 do not satisfy any one in the equation set 1.In this case, as the maximum radial displacement+d of driven roller 80, promptly at interval B is positioned at when being the position of θ d (+135 °) apart from axle+X, and the K color image begins to be transferred to be with on 70.The position of interval B, the position of θ d are that convenient the explanation at random is provided with.

When the K color image is beginning to be transferred to from K color image transfer printing starting point F θ when being with on 70, the starting point f0 of driven roller 80 first rotations is just at position F0 place.Therefore, the center of a K look image error Rke1 who causes because of interval B just occurs in 70 distances from range unit image transfer printing initial SL running m1=Rd θ d.Because finish transfer printing K color image by the once rotation of OPC 30, driven roller 80 will rotate twice during the transfer printing of K color image.Therefore, the 2nd K look image error Rke2 just occurs in 70 and runs to and the position at a distance of 1Sd=2 π Rd, the center of a K look image error Rke1.That is to say that because of twice K look image error Rke1 that interval B produces, Rke2 occurs on the cell picture zone P1, and the 2nd K look image error Rke2 be centered close to the position at a distance of Sd+m1 with SL.

Simultaneously, because the center C 1 of two

OPC

30,40, the distance L 1=1Sd+t3 between the C2, the position F2 that the transfer printing of C color image begins turn round apart from t3 from the starting point f1 that rotates the second time of driven roller 80 with 70.Therefore, because of the center of the C look image error Rce1 that causes of B at interval in rotation second time of driven roller 80, appear at 70 from the position of f1 running in position apart from m1.Thereby the center of a C look image error Rce1 is located in the C color image and begins the position of transfer printing line SL at a distance of m2=m1-t3.For ease of explanation, the girth when just being defined as 45 ° of driven roller 80 rotations corresponding to the distance of interval t3.Therefore, m2=Rd θ d-Rd45 °=Rd (θ d-45 °).Thereby, the center of a C look image error Rce1 just on the P1 of cell picture zone with twice K color error Rke1, the center difference of Rke2.

In the process of the rotation for the third time of the transfer printing of C color image and driven roller 80, cause the 2nd C color error Rce2 by interval B.The position of Sd is at interval moved in being centered close to 70 of the 2nd C look image error Rce2 from the center of C look image error Rce1.Therefore, the center of the 2nd C look image error Rce2 is located in the position at a distance of m2+Sd=Rd (θ d-45 °)+2 π Rd=Rd (2 π+90 °) with the initial SL of C color element image P1.

Because the center C 2 of C look OPC 40 and M look OPC50 and the distance between the C3 are L2=Sd+t3, the M color image just begins transfer printing from a F4.The point F4 range points F0 that the M color image begins transfer printing is 2Sd+2t3, and for example, range points f2 is that 2t3 is far away.Therefore, the center of a M look image error Rme1 who produces because of interval B on the P1 of cell picture zone is located in and puts the position of f2 at a distance of m1=Rd θ d.Therefore, during the transfer printing of M look, the distance between the SL of the center of image error Rme1 and cell picture zone P1 is exactly d-2Rd45 °=Rd of m3=m1-2t3=Rd θ (θ d-90 a °).The position of Sd is at interval moved in being centered close to 70 of the 2nd M look image error Rme2 that produces because of interval B from the center of M look image error Rme1.Therefore, the 2nd M look image error occurs in the position at a distance of m3+Sd=Rd (θ d-90 °)+2 π Rd=Rd (2 π+45 °) with the initial SL of M color image.Therefore, twice M look image error Rme1, Rme2 and K look and C look image error Rke1, Rke2, Rme1, the position difference that Rme2 occurs.

With reference to Figure 11 A, the center C 3 of M look organic photoconductor 50 and Y look organic photoconductor 60 and the distance between the C4 are L3=Sd+2t3.Therefore, the Y color image begin transfer printing some F6 just with 70 from position that a f0 moves 3Sd+4t3.Then, the center of a Y image error Rye1 who produces because of interval B during the 4th rotation of driven roller 80 just appears at and puts the position of F6 at a distance of m4.Because the distance between some F6 and the some f3 is 4t3, some F6 and the distance of putting between the f4 are exactly Sd-4t3.In addition, the distance of a some f4 and a Y image error Rye1 is m1.Therefore, m4=Sd-4t3+m1=2 π Rd-4Rd45 °+Rd θ d=Rd (2 π-45 °).The 2nd Y image error Rye2 is positioned at 70 and moves the position of Sd at interval from the center of a Y image error Rye1.Therefore, the 2nd Y image error occurs in the position at a distance of m4+Sd=Rd (4 π-45 °) with the line SL of Y color element image P1.As mentioned above, Y image error Rye1, Rye2 is different with the occurrence positions of K look, C look and M look image error, thereby on the P1 of cell picture zone a lot of image errors just takes place.

As mentioned above, by being aligned in the paired image error that image-region P1 takes place, the quantity of image error just can reduce greatly.Therefore picture quality is improved.

After this, image error (Rce1, Rce2) (Rye1, method Rye2) of aiming at C and two kinds of colors of Y mutually will be described with reference to Figure 11 A and 11B.For this reason, the imaging device system is set to satisfy the situation of the 6th equation of equation set 1.That is, two

OPC

40 and 60 situations that satisfy L6=qSd that are set to shown in Figure 12 A.Figure 12 A illustrates L6=3Sd.Like this, the center C 2 of C look and Y look

OPC

40 and 60 and the distance between the C4 are the integral multiples of the outer perimeter Sd of driven roller 80.Other distance L 1, L2, L3, L4 and L5 are not the integral multiples of periphery Sd.With reference to Figure 11 A and 12A, the change in location of the Y look OPC 60 among Figure 12 A only.Therefore, other OPC 30-50 is construed as and is arranged on the position identical as Figure 11 A.

When under the state shown in Figure 12 A, when a F0 begins transfer printing K color image, during two swing circles of driven roller 80, carry out transfer printing K color image.Therefore, shown in Figure 11 A and 11B, the first and second K look image errors (Rke1) that produce because of interval B (Rke2) take place in identical position.That is, the center of a K look image error (Rke1) be with 70 from a f0 (F0) running apart from m1=Rd θ d, and the 2nd K look image error (Rke2) is being with 70 from the f0 Sd+m2 that turns round.

Shown in Figure 11 B, the first and second C look image errors (Rce1) (Rce2) appear at identical position in the process of C color image transfer printing.That is, shown in Figure 12 B, turning round apart from d-Rd45 °=Rd of m2=m1-t3=Rd θ (θ d-45 °) from a F2 (the transfer printing initial SL of C color element image) with 70 in the center of C look image error (Rce1) for the first time.And being centered close to of the 2nd C look image error (Rce2) is with 70 to locate apart from m2+Sd=Rd (θ d-45 °)=2 π Rd=Rd (2 π+90 °) with some F2.

The center of the one M look image error (Rme1) just be with 70 from some F4 running apart from d-2Rd45 °=Rd of m3=m1-2t3=Rd θ (θ d-90 °).The 2nd M look image error Rme2 is being with 70 from some F4 running m3+Sd=Rd (θ d-90 °)+2 π Rd=Rd (2 π+45 °).

Because the center C of Y look OPC60 4 and center C 2 be at a distance of 3Sd, it is the distance of 3Sd from 3 times of the some F2 running girth Sd of C color image transfer printing that the some F6 of Y color image transfer printing is positioned at 70.Then, some F6 range points f4 distance be t3, and the center of a Y image error Rye1 who produces because of interval B is located in and puts f4 m1 position apart.Therefore, because a Y image error Rye1 is centered close to and puts F6, promptly line (SL) distance that begins transfer printing from the Y color image is the position with 70 running d-Rd45 °=Rd of m4=m1-t3=Rd θ (θ d-45 °)=m2, these two image errors (Rke1, Rye1) just aligned with each other in the P1 of cell picture zone.In addition, the 2nd Y image error Rye2's is centered close to and puts the F6 distance position with 70 running m4+Sd=m2+Sd=Rd (θ d-45 °)+2 π Rd=Rd (2 π+90 °).Therefore, the 2nd C look image error (Rce2) in the P1 of cell picture zone is identical with the SL distance with the 2nd Y image error (Rye2), thereby can be aligned with each other.

As implied above, passing through four all

OPC

30,40,50,60 are transferred to among the color image region P1 on 70, exist to comprise the overlapping (Rke1 of image error, Rye1) (Rke2 Rye2) in six interior image errors, lacks 2 than 8 image errors that produce in the structure of Figure 11 A.Therefore, make picture quality get a promotion, can improve reliability of products owing to the quantity of image error reduces.

In the embodiment that reference accompanying drawing 12A explains, only have blue or green and Y look

OPC

40 and 50 in the heart distance L 6 are integral multiples of Sd.Yet, if other distance L 1, L2, L3, L4, at least one among the L5 satisfies identical condition, and image error quantity aligned with each other can also increase.In addition, if Ro＞Rd, and system be set to satisfy L1=L2=L3=nSd (n=1,2,3...), 8 image errors can be reduced to 4 overlapping images, therefore, picture quality is improved.Owing to can understand these effects with reference to top description by Figure 12 A and 12B, for simple and clear the omission described.

Like this, in the description of the embodiments of the invention of the equation set of utilizing 1, the method that reduces the image error that the mistake circular error because of driven roller 80 causes is important.But this can not be interpreted as it is a kind of qualification.If because of the image error that the mistake circular error of backing roll 91 causes, also can utilize equation set 1 and reduce the generation of image error.

In other words, according to which have big radial displacement and influence imaging, system is set to satisfy at least one equation in the equation set 1 for driven roller 80 or backing roll 91.On the other hand, for other rollers, by the back operation,, also can reduce the mistake circular error, and the frequency that takes place because of the image error that produces with 70 backing roll can reduce also as finishing.

As mentioned above, to 7B, each

OPC

30,40,50,60 includes the interval A with maximum radial displacement+δ o with reference to Fig. 4 A.Image error that produces because of interval A such as image blurring, image stretch and image cut off etc., appear at each

OPC

30,40, on the coloured image that forms on 50,60 and be transferred to on 70 the transferred image.These will be explained with reference to Figure 13 in the back in detail.For example, in order to form the K color image, OPC 30 is rotated and the surface of this OPC 30 contacts with charging roller 35 rotations of filling predetermined potential with.But because the radial displacement in the A of interval+δ o, the radius R o of OPC 30 has increased+δ o, and A has maximum tangential velocity Vmax at interval.Because A more promptly passes through when rotation contact charging roller 35 at interval, the electric charge of A reception is few at interval, thereby lower than the other parts electromotive force of OPC 30.

In addition, the surface by from laser scanning device 31 emitted laser bundles scanning OPC 30 forms electrostatic latent image.During the process that forms electrostatic latent image, A has the tangential velocity Vmax of increase at interval.Therefore, A has reduced laser scanning quantity and has increased scan area at interval.Be formed on electrostatic latent image on the OPC 30 when the developer roll 33, toner-particle just is adsorbed onto on the electrostatic latent image from developer roll 33.Therefore, just obtain visual picture.Yet during this process, the A contact is faster by the speed of developer roll 33 at interval, and the quantity that scans the laser on the electrostatic latent image is just not enough.Thereby just the developer that can not adsorb q.s is to electrostatic latent image, and the developer that is adsorbed onto on the electrostatic latent image fogs because of too fast tangential velocity.By a series of operation, on OPC 30 surfaces, obtain visual picture as charging, laser scanning and development etc., on the A of interval, just there is image error, cut off etc. as image blurring, image stretch and image.

The last description, visual picture are formed on OPC 30 surfaces, but both have image error at interval A place prior to being transferred to be with on 70.Be transferred to the visual picture on 70 and have image error because of interval A.As mentioned above, because the interval A that the mistake circular error of

OPC

30,40,50,60 causes causes producing image error, it is independent of the mistake circular error that driven roller 80 produces.Because because of

OPC

30,40,50,60 mistake circular error image error occurs on each

OPC

30,40,50,60, and coloured image just has a large amount of image errors.For example, if each

OPC

30,40,50,60 is designed to cell picture of twice formation of every rotation, on each

OPC

30,40,50,60, just can form two image errors.Thereby full-colour image just has 8 image errors.

Simultaneously, illustrated to 7B as reference Fig. 4 A, the center that causes the interval A that image error takes place is arranged on a pre-position with respect to the positioning element 33b of driven coupler 33.In other words, mark 31a is formed on the position that becomes predetermined angular on the bulging body 31 with the center of interval A, and assembles

OPC

30,40,50,60 by registration mark 31a and positioning element 31b.In addition,

OPC

30,40, and 50,60 can utilize anchor clamps and do not need extra measurement mechanism to assemble.

After this, will describe and ought utilize

OPC

30,40 respectively, the image error that produces during 50,60 formation images is installed each

OPC

30,40,50,60 and is made that the center of A becomes the predetermined angular location with respect to positioning element 33b at interval.In addition, will method and the effect that reduce image error according to embodiments of the invention be described.

The main interval A that pays close attention to each

OPC

30,40,50,60 with radial displacement+δ o is described.Yet similarly qualification also can be applicable to and have-zone of δ o.Because have+zone of δ o in the problem brought of image error in the zone of the problem ratio-δ o that brings of image error serious, therefore, the zone of mainly right+δ o is described.

For ease of explanation, suppose that driven roller 80 and backing roll 91 are desirable circles, do not lose circular error.Also suppose because of the different velocity variations that can not produce of the radial displacement of driven roller 80 and backing roll 91, be with 70 to be with operate at constant speed with 70.

Shown in Figure 14 A-14D, the OPC of various colors 30,40,50,60 is provided with respectively as follows, make each positioning element 33b that drives coupler be positioned at from axle Y in the counterclockwise direction (+angle) each other in the position of different angles.In this case, the initial SL of cell picture P2 is transferred to and each OPC 30,40 in proper order, 50,60 correspondences with 70 contact position Po1, Po2, Po3 on the Po4, thereby forms the coloured image of double exposure.Each OPC 30,40,50,60 is set to have A1 at interval, A2, and A3, A4, each interval becomes the predetermined angular place all to have maximum radial displacement+δ o every positioning element 33b.In addition, shown in Figure 14 A-14D, suppose that each OPC has different " attitude (posture) " when the beginning transfer printing.Such a case will be described, the initial SL of each cell picture P2 is transferred on each OPC 30,40,50,60+some Po1, Po2, Po3 and Po4 place on the Y-axis.In other words, " attitude of each OPC 30,40,50,60 " meaning is each OPC30 when the beginning of each coloured image K, C, M and the transfer printing of Y order, 40,50,60 attitude.

Shown in Figure 14 A, if begin to print when K look OPC 30 contacts with axle+Y, just locate to be rotated counterclockwise angle θ 1 with respect to axle+Y at the center of A1 at interval.At Figure 14 A in 14D, at interval the center of A1-A4 all with positioning element 33b angle at 45.Therefore, the pre-position because of the cell picture zone P2 of interval A1 on 70 produces K look image error Oke.That image error Oke comprises is image blurring, image stretch and image cut off.Promptly, because the tangential velocity Vmax of OPC 30 in the variation on the A of the interval on the surface of OPC 30 faster than other tangential velocity variation at interval, on OPC, just form the electrostatic latent image (on the other hand, because zone-δ o has minimum tangential velocity, the electrostatic latent image that will shrink) that stretches.If developer roll 33 contact OPC 30 carry out develop, image blurring situation appears in the nominal speed that will be different from OPC because of the speed of interval A at interval A place.When this image is transferred to when being with on 70 by said process, will interval A1 and contact interval A1 be with 70 between produce velocity contrast, and cause image blurring.The center that K look image error Oke takes place is in the position at a distance of lok=Ro1 θ 1 with initial SL.

As shown in Figure 14B, the center of the interval A2 of C look OPC 40 is located being θ 2=+135 ° with respect to axle+Y.In this case, the error Oce of the C color image that causes because of interval A2 that occurs at cell picture P2 place, its position is different with the position of K look image error Oke.That is, C look image error Oce appears at the position apart from initial loc=Ro2 θ 2.

Shown in Figure 14 C, the center of the interval A3 of M look OPC50 is located being θ 3=+225 ° counterclockwise with respect to axle+Y.Therefore, the M look image error Ome that causes because of interval A3 that occurs at cell picture P2 place, its position is different with the position of K look and C look image error Oke and Oce.That is, M look image error Ome appear at initial SL at a distance of lom=Ro3 θ 3 places.

Shown in Figure 14 D, the center of the interval A4 of Y look OPC60 is located being θ 4=+315 ° counterclockwise with respect to axle+Y.Therefore, the Y image error Oye that the interval A4 because of OPC60 that occurs at cell picture P2 place produces, its position and K look, C look and M look image error (Oke) (Oce) position of (Ome) are different.That is, Y image error Oye appear at initial SL at a distance of loy=Ro4 θ 4 places.

With reference to Figure 14 A and 14D, if Ro1=Ro4=Ro, the distance between the center of image error Oke and Oce is exactly loc-lok=Ro (θ 2-θ 1).Thereby, since the misalignment on the P2 of cell picture zone of colour imaging error, each colour imaging error Oke, Oce, Ome, Oye are located in different positions on the coloured image of double exposure, and have reduced picture quality.

15A and 15B describe example in detail below with reference to accompanying drawings.

Figure 15 A with the single-

view example OPC

30,40,50,60 of Figure 14 A to 14D.In Figure 15 A, because with reference to starting point Po1, Po2, Po3, Po4 describe each

OPC

30,40,50,60 each coloured images of transfer printing, do not consider the time in this description.

Figure 15 B shows and

OPC

30,40 with sinusoidal form, the radial displacement of every kind of color of 50,60 swing circle correspondence (δ ok, δ oc, δ om, δ oy).In the figure, do not consider each OPC30, the interval at 40,50,60 center, based on the transfer printing point Po1 of every kind of color, Po2, Po3, Po4 shows the radial displacement and the image error of every kind of color.The radius of each

OPC

30,40,50,60 is unified, promptly from Ro1=Ro2=Ro3=Ro4.

First curve map of Figure 15 B illustrates the radial displacement (δ ok) according to the swing circle of OPC 30, and the transfer printing of supposing K look OPC 30 is to begin in the position as Figure 14 A and 15A.If supposition K color element image is finished when OPC 30 rotations one time, the transfer printing of K color image is from a Po1, so, because of interval A1 in a swing circle (cell picture zone; P2) produce the center of K look image error Oke in.That is, transfer printing K color image with 70 from the advance distance of 1=Ro45 ° of lok=Ro θ of SL point.

Second curve map of Figure 15 B illustrates the radial displacement (δ oc) of basis as the swing circle of the set C look OPC 40 of Figure 14 B.The transfer printing of C look is from a Po2, and K look transfer printing starting point Po1 aims at a line SL who wherein begins transfer printing C color image at a Po2 place.With reference to Figure 15 A, actual on 70 two some Po1 and Po2 between be the rotation center C1 of two OPC 30,40 at interval, the distance L 1 between the C2.Therefore, the K color image begins just to overlap with the some Po2 that begins transfer printing with C color image behind the 70 travel distance L1 from a SL of Po1 transfer printing.In Figure 14 B, at interval A2 is arranged on the phase place of from a Po2 to θ 2 (115 °), and therefore, the center of C look image error Oce is just based on a swing circle (cell picture zone; P2) on the SL, that is, be positioned at 70 from a Po2 advance apart from loc=Ro θ 2 (115 °).As shown in Figure 14B, if two image error Oke, Oce produces on the P2 of cell picture zone, just shows two image error Oke on the curve map, and the interval at the center of Oce differs loc-lok=Ro (θ 2-θ 1).

The 3rd curve map of Figure 15 B illustrates the radial displacement (δ om) of basis as the swing circle of the set M look OPC50 of Figure 14 C.The center of A3 is in the phase place of the some Po3 that begins transfer printing from the M look to θ 3 (225 °) at interval.The M look image error Ome that produces because of interval A3 forms in the M color image when M look OPC50 rotates θ 3.Therefore, the center of M look image error Oce be with 70 from the advance distance of lom=Ro θ 3 of a Po3.When the swing circle of OPC50 is divided into 360 °, just rotating about 225 ° from a Po3 apart from lom=Ro θ 3.Therefore, two image error Oce, in the heart distance is exactly lom-loc=Ro (θ 3-θ 2) among the Ome.Two some Po2, the rotation center C2 of two

OPC

40,50 of time interval between the Po3, the distance L 2 between the C3, by

OPC

30,40 double exposures, the SL of K color image and C color image aims at the SL of M color image at a Po3 place.

The 4th curve map of Figure 15 B shows the radial displacement (δ oy) of basis as the swing circle of the set Y look OPC60 of Figure 14 D.At interval the center of A4 is in the phase place of 4 (315 °) from a Po4 to θ.Therefore, the Y image error Oye that produces because of interval A4 is a swing circle (cell picture zone as OPC60; When P2) being divided into 360 °, rotating about 315 ° and locate to produce.Therefore, the center of Y image error Oye be with 70 from the advance distance of 4=Ro215 ° of loy=Ro θ of a Po4.Two image error Ome, in the heart distance is exactly from loy to lom=Ro (θ 4-θ 3) among the Oye.When each coloured image of double exposure, can image error appear in different each positions, and therefore, the quality of the coloured image of double exposure descends.

Curve map shown in Figure 15 B is with respect to a swing circle (cell picture zone; The phase place difference of the P2) radial displacement of every kind of color (δ ok, δ oc, δ om, δ oy), their radial displacement is different.Therefore,, supposition unit image-region P2 forms if being swing circle by OPC, just at the image error Oke of every kind of color of diverse location appearance, and Oce, Ome, Oye.Will four image errors appear at the diverse location place on the P2 of cell picture zone.

In Figure 14 D and Figure 15 B, the radius of each

OPC

30,40,50,60 is unified, is Ro at Figure 14 A, and a cell picture is once to form by rotation among each

OPC

30,40,50,60.Yet, in fact can be according to

OPC

30,40, the size of 50,60 radius by once, once half or twice rotation form a cell picture.At this moment, at least in four of cell picture region generating or more image errors of full-colour image, therefore, image quality decrease.

In addition, in above stated specification, the radius of having supposed all OPC all is identical.Certainly, those skilled in the art can understand the incomplete identical situation of radius that above-mentioned principle also can be applied to the OPC drum.For example, the distance between the rotation center of control OPC, also can obtain identical effect by the distance between the contact point of control OPC.That is to say that each OPC has contact point being with on 70.By between the control OPC contact point along the length of band, because the image error that the radius deviation of OPC causes can be overlapping, and minimizing therefrom.In this case, because radius is unequal, the length between the rotation center needn't equal along the length between the contact point of band.

If OPC 30, the position of each radial displacement+δ of 40,50,60 is based on each OPC30,40,50,60 initial transfer printing point is aimed at, promptly, if each OPC 30-50 is conditioned and is arranged to each image error Oce, Ome, Oye is offset specific range and produces, and one the four error Ote that the look image error is overlapping then only occurs.The 5th curve map shown in Figure 15 B, the radial displacement δ ok of each

OPC

30,40,50,60, δ oc, δ om, δ oy is in unit swing circle (cell picture zone; P2) demonstrate the pattern of rule in.Because in unit swing circle (cell picture zone; P2) each radial displacement δ ok in, δ oc, δ om, δ oy aims at, the image error Oke of each color, Oce, Ome, Oye aims in identical phase place.

The 5th curve map shown in Figure 15 B shown that each of 50,60 is to the production of punctual image error as four OPC 30,40.Yet,, can significantly reduce the quantity of image error even when the image error of at least two OPC is overlapping.Below, will describe the method and the operating effect of the image error of overlapping two or more OPC in detail.

The transfer printing dot sequency of each OPC describes because Figure 14 A is based on to 14D and 15B.Each OPC and explain relation between OPC when following illustrative explanation will be according to installation system corresponding to the engagement relationship between the driving coupler of OPC.

Therefore, describe to 16D referring now to Figure 16 A.

Figure 16 A is depicted as the point when initial transfer printing K look OPC 30.K look OPC 30 is D1 with respect to the position with 70 beginning transfer printings, the position of contact zones 70 is E1, and the angle between the center of E1 and maximum radial displacement region A1 is that α 1 is (because current accompanying drawing is different from Figure 14 A to 14D, Figure 14 A is based on the transfer printing point of the order of each OPC to 14D, angle [alpha] 1-α 4 is used among Figure 16 A).At this moment, C look OPC 40 and be D2 with the contact point between 70, and the position of corresponding C look OPC 40 is at E2, and the angle between the center of the maximum radial displacement region A2 of E2 and C look OPC 40 is α 2.It is D3 in the position on 70 that M look OPC50 begins transfer printing, and the contact position of M look OPC50 is E3, and the angle between the center of E3 and maximum radial displacement region A3 is α 3.Y look OPC60 and be D4 with the contact point between 70, and the position of corresponding Y look OPC60 is E4, and the angle between the center of the maximum radial displacement region A4 of E4 and Y look OPC60 is α 4.Distance between C1 and the C2 is L1, and the distance between C2 and the C3 is L2, and the distance between C3 and the C4 is L3, and OPC 30,40, and 50,60 radius is respectively Ro1, Ro2, Ro3, Ro4.Can under the situation of an equation in the equation set 2 below satisfying, OPC be installed.

(equation set 2)

{2π·l+(α2-α1)}·Ro＝L1，(1＝0，1，2，...)，(Ro＝Ro1＝Ro2).........①

{2π·m+(α3-α1)}·Ro＝L1+L2，(m＝0，1，2，...)，(Ro＝Ro1＝Ro3)......②

{2π·n+(α4-α1)}·Ro＝L1+L2+L3，(n＝0，1，2，...)，(Ro＝Ro1＝Ro4)...③

In Figure 16 A, K look OPC 30 begins to be transferred to K color element image Pk at first.The initial SL of K color element image Pk is from 70 position D1 beginning, and joins with the E1 of OPC 30.The center of A1 is being α 1 angle from E1 along axle+Y at interval.Position D2 on C look OPC 40 contact zones 70, the at interval position that is centered close to contact position E2 rotation alpha 2 angles from the OPC 40 of A2.Equally, the center of the interval A3 of M look OPC50 and Y look OPC60 and A4 is in the position from separately E3 and E4 rotation alpha 3, α 4 angles.

Under the state of Figure 16 A, the K color image is transferred on the K color element image Pk, the center of the K look image error Oke that produces because of interval A1 with the position of initial SL at a distance of b1=Ro α 1=Ro1 α 1.Shown in Figure 16 B, when K look image error Oke is positioned at C look OPC 40 and during with 70 contact position Po6, if the center of the C look image error Oce that on C color element image Pc, produces because of the interval A2 of OPC 40, position alignment with the center of K color error Oke, two color error Oke then, Oce is just at identical location overlap.Condition above wherein satisfying forms following equation:

Ro·α1+L1＝Ro·α2，(Ro＝Ro1＝Ro2).......................(1)

Because distance L 1 is in the rotation girth 2 π Ro of OPC 30, like this, L1＜2 π Ro, equation (1) can be summarized as follows:

Ro·α1+L1＝Ro·(α2+2π·1)，(1＝0，1，2，...).......................(2)

Above-mentioned equation (2) can make following formula into:

{2π·1+(α2-α1)}·Ro＝L1，(1＝0，1，2，...).........................(3)

Above-mentioned equation (3) is with respect to first equation in the equation set 2.If two

OPC

30,40 are configured to satisfy equation (3), because of the interval A1 of K look and C look

OPC

30,40, the image error Oke that A2 produces, Oce is just at identical location overlap.In concrete condition, when each OPC30 is set in imaging device, 40 o'clock, K look OPC 30 at first was set to S1 and sets the Ro value.Then, if a certain α of K look OPC30 1 value during with the first equation substitution in the equation 2, just can obtain α 2 values of C look OPC 40.Therefore, if along axle X and Y C look OPC 40 is set rightly based on α 2 values that obtain above, image error Oke, Oce just can be overlapping.

In addition, shown in Figure 16 A, K look image error Oke be centered close to from initial SL at a distance of the position of b1=Ro α 1=Ro1 α 1.Shown in Figure 16 C, when K look image error Oke is positioned at M look OPC50 and during with 70 contact position Po7, if the center of the M look image error Ome that on M color element image Pm, produces because of the interval A3 of M look OPC50, position alignment with the center of K color error Oke, two color error Oke then, Ome is just at identical location overlap.For this reason, the equation (4) below two

OPC

30,50 need to satisfy:

Ro·α1+L1+L2＝Ro·(α3+2π·m)，(m＝0，1，2，...)，(Ro＝Ro1＝Ro3)......(4)

If the equation (4) above rewriting, second equation of equation set 2 can be derived as follows:

{2π·m(α3-α1)}·Ro＝L1+L2，(m＝0，1，2，...)，(Ro＝Ro1＝Ro3).........(5)

For the Y image error Oye that will the interval A4 because of Y look OPC60 in K look image error Oke and cell picture Py produces aims at, shown in Figure 16 D, just need when with 70 position D1 when a Po8 moves the position of b1=Ro α 1=Ro1 α 1, the center of interval A4 is arranged on the Po8.This condition can be expressed as following equation (6):

Ro·α1+L1+L2+L3＝Ro·(α4+2π·n)，(n＝0，1，2，...)，(Ro＝Ro1＝Ro4)...(6)

Above-mentioned equation (6) can be rewritten into:

{2π·n+(α4-α1)}·Ro＝L1+L2+L3，(n＝0，1，2，...)，(Ro＝Ro1＝Ro4).....(7)

Equation (7) is to change from equation (6), and it is corresponding to the 3rd equation of equation set 2.

Equation set 2 conditions as described above are to be used to control position that OPC 40-60 is installed, thus the K look image error Oke overlaid that the image error because of a generation among the OPC 40-60 can be produced with the interval A1 because of K look OPC 30.

In addition, opposite with equation set 2, in order to allow the image error overlaid that produces among the adjacent at least

OPC

30,40,50,60, imaging device need be configured to satisfy at least one in the equation:

(equation set 3):

{2π·l+(α2-α1)}·Ro·(1±0.05)＝L1，(l＝0，1，2，...)，(Ro＝Ro1＝Ro2).....①

{2π·m+(α3-α2)}·Ro·(1±0.05)＝L2，(m＝0，1，2，...)，(Ro＝Ro2＝Ro3).....②

{2π·n+(α4-α3)}·Ro·(1±0.05)＝L3，(n＝0，1，2，...)，(Ro＝Ro3＝Ro4).....③

Wherein the 1. equation in the equation set 3 is corresponding with first equation of equation set 2.This equation represents to aim at the image error Oke that produces because of two

adjacent OPC

30,40, the condition of Oce.Certainly, above-mentioned equation is represented the distance between the rotation center of OPC.Optionally, can control distance between the contact point of each OPC on according to the orientation of OPC roller with 70.

Second equation that satisfies equation set 3 represents to aim at the interval A2 because of two adjacent C looks and M look

OPC

30,40, the image error Oce that A3 produces, the condition of Ome, and can understand the method that the image error of two

OPC

30,40 is overlapping easily by above-mentioned method.In other words, be provided with, just can obtain α 3 values of M look OPC50 by second equation of equation set 3 if the value of the α 2 of C look OPC40 is setting with L2 value and Ro value.Therefore, based on α 3 values M look OPC50 is set, just can allows two image error Oce, Ome is overlapping.

The 3rd equation that satisfies equation set 3 represented will be because of M look and Y look OPC50,60 interval A3, the image error Ome that A4 produces, the condition that Oye is overlapping.At this moment, two OPC50,60 image error Ome, Oye can be with overlapping to the illustrated identical mode of 16D as Figure 16 A, i.e. the image error Oce of other colors, Ome, among the Oye one K look image error Oke that produces with interval A1 because of K look OPC 30.In other words, when L3 and Ro were set to a setting value, M look OPC50 was at first installed α 3 values of the M look OPC50 after just obtaining installing at an ad-hoc location.The 3rd equation then α 3 values being brought into equation set 3 just can obtain α 4 values.Therefore, based on α 4 values that obtain Y look OPC60 is set, just can allows two image error Ome, Oye is overlapping.

In embodiments of the invention, the center C 1 of each

OPC

30,40,50,60, C2, C3, the distance between the C4 is to be uniformly set to be L1=L2=L3.Therefore, equation set 2 can be rewritten as follows:

(equation set 4):

{2π·l+(α2-α1)}·Ro·(1±0.05)＝L1，(1＝0，1，2，...)，(Ro＝Ro1＝Ro2).........①

{2π·m+(α3-α1)}·Ro·(1±0.05)＝2L1，(m＝0，1，2，...)，(Ro＝Ro1＝Ro2＝Ro3)............................................................................. ②

{2π·n+(α4-α1)}·Ro·(1±0.05)＝3L1，(n＝0，1，2，...)，(Ro＝Ro1＝Ro2＝Ro3＝Ro4).................................................................................③

With reference to the description of Fig. 4 A to 7B,

OPC

30,40,50,60 is installed in an identical manner, make the interval A1 of each

OPC

30,40,50,60, A2, A3, A4 is positioned at identical phase place with respect to the positioning element 33b of driven coupler 33.Certain above-mentioned equation is represented the distance between the rotation center of OPC.Optionally, can control distance between the contact point on 70 of each OPC with respect to the orientation of OPC roller.

In this case, can obtain maximum radial displaced position and L1 on reference OPC, Ro, that is, and the position of interval A1 (α 1).In this embodiment, K look OPC 30 is set to reference to OPC.Therefore, therefore the maximum radial displaced position (α 2, α 3 and α 4) that obtains other OPC 40-60 installs each OPC 40-60 to satisfy equation 2 and 3.For the position of visual judgement radial displacement, the positioning element 33b of driven coupler can fix in factory with predetermined interval (for example, 45 °) with respect to radial displacement position separately, shown in Fig. 4 A.Therefore,

OPC

30,40, and 50,60 initial position just can be determined with reference to positioning element 33b.

And after obtaining the maximum radial displaced position (α 2, α 3 and α 4) of other OPC 40-60 with respect to the position alpha 1 of reference OPC 30, just can be by two following at least methods with

OPC

30,40,50,60 are installed on the imaging device.

As first method, as mentioned above, by with the positioning element 33b of driven coupler with respect to the mode that maximum radial displacement+δ locatees at a predetermined angle, each OPC 30,40,50,60 is installed.Among the OPC one, promptly OPC 30 is connected to and drives on the coupler 133, as shown in Figure 3.Under the state that OPC 30 is mounted, utilize predetermined sniffer can detect α 1.Under this situation, by with L1, L2, L3, Ro and α 1 are updated in second and the C grade formula of equation set 2 and obtain α 2, α 3 and the α 4 of other OPC40-60.Maximum radial displacement+δ the o that utilizes sniffer control OPC 40-60 to be satisfying the α 2 that is obtained, α 3 and α 4, and OPC 40-60 just with drive coupler 134,135 and 136 joints.Another example according to first method, when the driving coupler 133 that is connected to as on the K look OPC 30 of reference OPC is set at the precalculated position, and other driving coupler 134-136 is corresponding to the α 2 that is obtained, when α 3 and α 4 are provided with, OPC 30,40,50,60 can be connected on the driving coupler 133-136.Nature can utilize suitable detecting devices to regulate the positioning element that drives coupler 133-136.

Second method formula that OPC is set is to use anchor clamps.For example, shown in Figure 17 A, use grip device 300, a plurality of reference drum body 330,340,350,360 adjustable grounds are installed on the jig frame 310.With reference to rousing body 330,340,350,360 corresponding to the colored OPC 30-60 parts that are installed in the imaging device.Preferably, with reference to the interval of drum body 330,340,350,360 and the interval identical (Fig. 3) of the driving coupler 133-136 of the driver element 100 that OPC is installed.Corresponding to

OPC

30,40,50,60 driven coupler 33 is provided with driven coupler 333,343,353 and 363 with reference to drum body 330,340,350,360 leading section separately.Therefore, driven coupler 333,343,353 and 363 with corresponding driving coupler 133-136 complementary fit separately.In addition, be appreciated that driven coupler 333,343,353,363 positioning element is set at

OPC

30,40, on the position of the positioning element 33b same phase of 50,60 driven coupler 33, promptly become a predetermined angular place with maximum radial displacement+δ o of OPC relatively.

Simultaneously, with reference to drum body 330,340,350,360th, rotatably be inserted in the adjustment hole 313 that forms with predetermined space on the jig frame 310.In addition, jig frame 310 has corresponding to each tightening member 320 with reference to drum body 330,340,350,360.A plurality of tightening members 320 are with their ends separately and the mode that is inserted into reference drum body 330,340,350,360 contacts in the adjustment hole 313, by being threadably fastened on the jig frame 310.Therefore, when tightening member 320 rotation directions with reference to drum body 330,340,350,360 o'clock, their end with closely contact with reference to drum body 330,340,350,360, thereby immovably fixed with reference to rousing body 330,340,350,360.On the other hand, when tightening member 320 whizs with reference to drum body 330,340,350,360 o'clock, just be separated from each other with reference to drum body 330,340,350,360 and tightening member 320, thereby just can in adjustment hole 313, rotate with reference to drum body 330,340,350,360.

With grip device 300, with reference to the position of drum body 330,340,350,360, rather than be installed to

OPC

30,40,50,60 on the driver element 100, just can Be Controlled and fixing to satisfy

equation

2 and 3.

In order to control reference position, can use first above-mentioned method with reference to drum body 330,340,350,360.In other words, detect predetermined reference drum style, just can obtain other α 2, α 3 and α 4 by α 1 with reference to drum body 340-360 as with reference to behind the α 1 that rouses body 330.Based on the α 2 that obtains, α 3 and α 4 just can utilize predetermined sniffer sequentially to control and consolidate each and decide with reference to the position of rousing body 330,340,350,360.

After the reference position with reference to drum body 330,340,350,360 is determined, grip device 300 and driver element 100 are just close to each other, and the position is controlled with reference to drum body 330,340,350,360 driven coupler 333,343,353,363 just engages with driving coupler 133-136.Because driven coupler 330-363 fixes, drive coupler 133-136 just suitably rotate with driven coupler 333,343,353,363 are connected.When the position Be Controlled that drives coupler 133-136 and with driven coupler 333,343,353, behind 363 joints, grip device 300 and driver element 100 are just with respect to reference drum body 330,340,350,360 along reference drum body 330,340,350,360 move axially makes to drive coupler 133-136 and driven coupler 333,343, opened in 353,363 minutes.Wherein the mobile anchor clamps of driver element 100 available dedicated move and are connected with grip device 300, or selectively, grip device 300 can be shifted to imaging device, and driver element 100 is installed on the imaging device, thus the driving coupler 133-136 of control drive unit 100.

Drive coupler 133-136, after being connected on the driven coupler 333,343,353,363 and separating from it, just be engaged to

OPC

30,40, on 50,60 the driven coupler 33.Be fixed owing to drive the position of coupler 133-136,

OPC

30,40, and 50,60 just can be set to satisfy

equation

2 and 3 definitely.

Therefore, by using grip device 300, just can save installation time during batch process, and be convenient to the control of the radial displacement of OPC.

Figure 17 B show with grip device 300 ' the third method.Grip device 300 shown in Figure 17 B ' be similar to 300 shown in Figure 17 A, therefore, components identical is in the following description just with identical reference marker.Yet, the grip device 300 of Figure 17 B ' in, on the one end, have driven coupler 333,343,353,363 respectively with reference to drum body 330,340,350,360, and on the other end, have gear 371,372,373,374 respectively.Idle pulley 345 is arranged between the gear 371,372,373,374, makes each gear 371,372,373,374 be set to rotation with being relative to each other.Be provided with reference to drum body 330,340,350,360 with predetermined interval.Therefore, by regulating a position, also just other positions have therefore been regulated with reference to the drum body with reference to the drum body.When the position is conditioned, just be fixed fixing process need one tightening member 320 with reference to the drum body.Do not resemble shown in Figure 17 A, each of Figure 17 B be with reference to drum body 330,340,350,360th, and can being correlated with each other with them, mobile mode connects.Therefore, only need single retaining element 320 to fix in the drum one 330, just can fix the bulging body 330,340,350,360 of all reference.For example, if fix first with reference to drum body 330, just fixed other reference drum body 340,350,360 because of gear 371-375 by tightening member 320.As, by using α 1 value of grip device 300 shown in Figure 17 B ' just can obtain with reference to roller 330.Based on α 1 value that obtains, corresponding position with reference to drum body 330 just is conditioned, and just can determine other α 2, α 3 with reference to drum body 340,350,360, the value of α 4 automatically, and is therefore, also adjusted with reference to the position of drum body 340,350,360 then.Thereby, image carrier can simply and effectively be set.

When the radius R o of each

OPC

30,40,50,60 is identical, and the distance between the center of

OPC

30,40,50,60 equates that all (during L1=L2=L3=2 π Rox (x=1,2,3...)), all α 2, α 3, α 4 are exactly identical value.Therefore, as shown in Figure 3, corresponding to

OPC

30,40,50,60 are provided with the positioning element that drives coupler 133-136 equably by edge+A axle, are fastened to the positioning element that drives the

OPC

30,40,50,60 on the coupler 133-136 and just can be positioned.Thereby, just can during the order transfer printing, control because of

OPC

30,40,50,60+image error of every kind of color that δ o produces is overlapping at identical relative position.With reference to the description of Fig. 4 A to 7B, the OPC30 that can harmonize by the positioning element 33b of driven

coupler

33,40,50,60+δ o, thus realize the present invention.

Generally, i)

OPC

30,40,50,60 and driven roller 80 all lose circular error respectively.For be easy to control because of lose circular error+δ o and+frequency that image error that δ d causes occurs,

OPC

30,40,50,60 and driven roller be constructed such that the positioning element 33b of driven

coupler

33 and 83 and 83b be positioned at+δ o and+a certain position that δ d is corresponding.

Ii) embodiment and effect are as mentioned above, when implementing to satisfy the condition of equation set 1, make image error (Rke, the Rce that produces because of at least one the mistake circular error in driven roller 80 and the backing roll 91, Rme, at least two in Rye) are overlapping at identical relative position place.Wherein according to the relative size of the radius R o of the radius R d of driven roller 80 and OPC, and ignore the quantity of the image error that on cellar area, produces, can overlappingly be created in the image error on the image-region of corresponding OPC.

Iii) hereinbefore, equation set 2 and equation set 3 are described as separately because of

OPC

30,40,50,60 lose image error (Rke, the Rce that circular error produces, Rme, Rye) at least two the superimposed conditions in, and do not consider the mistake circular error of driven roller 80 and backing roll 91.More specifically, for any one image error with respect to predetermined OPC 30 overlapping other OPC 40-60, system is set to satisfy at least in equation set 2 or 3 conditions.For the image error of overlapping at least two adjacent OPC, system is set to satisfy at least at least one in the condition of equation set 3.Applicable equations group 2 and do not consider L1 at 3 o'clock usually, L2 and L3, promptly

OPC

30,40, the relative size of the distance between 50,60 the center.When L1=L2=L3, system is configured to satisfy equation set 4 usually.In other words, consider assembling and with other the relation of part dimension, product roughly is manufactured into and satisfies L1=L2=L3, during applicable equations group 4, effectively reduces the frequency that image error takes place.

The 3rd step as the frequency that reduces the image error generation, now describe corresponding to each OPC30,40,50,60 come overlapping existence to lose the backing roll 91 of circular error and the another kind of method of the image error that at least one produced in the driven roller 80 because of losing the image error that circular error produces.

As described in Fig. 8 A and 8B, for example, because of image error Rke takes place in the interval B of driven roller 80 on the image-region of K look OPC 30.Also be because B at interval, on other the image-region of OPC50-60, image error Rme also take place, Rye.The image error Oke that produces because of the interval A of K look OPC 30 is as described in top Figure 15 A and the 15B.Because of the interval A1 of other OPC 40-60, A2, A3 and A4 produce image error Oce, Ome and Oye.When by

OPC

30,40,50,60 and the interval A1-A4 of driven roller 80 and the same position place of at least two image errors on that B produces respectively when overlapping with 70, can reduce the influence of the image error on the coloured image of last formation.

With reference to Figure 18 A, θ d represents by the angle from the counterclockwise commentaries on classics of X-axis that is formed centrally among the B of interval, at interval the center of B defines the radial displacement+δ d on driven roller 80, and θ ox represent by on 70 rotation direction radial displacement+δ o of the OPC of x position forms from+Y-axis the angle of commentaries on classics counterclockwise.By method described below, because of the image error Rke that interval B produces, Rce, at least one among Rme and the Rye (as Rke), can with each OPC 30,40,50, image error Rke in 60, corresponding image error (Oke) is overlapping with 70 identical positions among the Rce, Rme and Rye.The interval A that driven roller 80 and OPC 30 are set so that OPC 30 with on 70, have maximum influence for the maximum tangential velocity Vmax of the driven roller 80 that produces because of interval B with 70 contact positions, promptly, when the direction of maximum tangential velocity Vmax and+Y-axis on time, shown in Figure 18 A dotted line.Like this, for corresponding to driven roller 80 overlapping a plurality of OPC30, in 40,50,60 at least one, the image error of OPC 30 for example, system is set to satisfy at least at least one in the equation group 5.

(equation set 5):

Rd θ d=(2 π l+ θ ox) Rox (1 ± 0.05) (l=1,2,3 ...), (x=1,2,3 ...) and Rd=zRox, (z=2,3,4,5 ...) ... ... ... ... ... ... ... ... ... 1.

Rd·θd＝Rox·θox·(1±0.05)，Rd＝θox(x＝1，2，3，...).....................②

(2 π h+ θ d) Rd=Rox θ ox (1 ± 0.05), (h=1,2,3 ...), (x=1,2,3 ...) and Rox=kRd, (k=2,3,4,5 ...) ... ... ... ... ... ... ... .... 3.

That is, if system is set to satisfy in the equation set 5 at least one, because of driven roller 80 and OPC30,40,50,60 the error that radial displacement produced just can be at the identical location overlap on 70, therefore, image error just only occurs in the position of superimposed images.

At first, suppose δ o=δ d, the situation of Rox＜Rd is described below.

According to first equation of equation set 5, when the radius R d of the driven roller 80 big integral multiple of radius R ox than pairing OPC, this integral multiple is more than or equal to 2 o'clock, because of the image error that driven roller 80 and target OPC produce can be superimposed.

Now be described in detail with reference to Figure 18 A and 18B.Figure 18 A shows the situation that system is set to not satisfy first equation of equation set 3.Wherein Xiang Guan OPC is K look OPC 30, and it is set at primary importance, and Rd=2Ro1.

When Rd=2Ro1, when driven roller 80 rotates a circle, 30 two weeks of rotation of OPC.Suppose that cell picture was formed by OPC two weeks of 30 rotations.Thereby, image error that will in a cell picture zone, take place to produce and two image errors that produce because of the interval A1 of OPC 30 because of the interval B of driven roller 80.

Below, be set to satisfy first equation of equation set 5 with reference to Figure 18 A descriptive system, allow image error that interval B because of driven roller 80 produces with because of a method of aiming in two image errors of the interval A1 generation of OPC 30.

More specifically, shown in Figure 18 A, OPC 30 center of A1 at interval is set to change o1=315 ° of θ ox=θ counterclockwise with respect to+Y-axis, and the center of B is set to change θ d=315 ° clockwise with respect to+X-axis at interval.When beginning transfer printing K color image in this state, the center of the image error Rke that produces because of interval B during with a swing circle of 70 just occurs in 70 positions from the mobile Rd θ of starting point " Po1 " d.In other words, the center of the image error Rke that is produced by driven roller 80 in the cell picture is located in the position at a distance of Rd θ d with SL.

When driven roller 80 circles, OPC 30 changeed for two weeks.Therefore, first and second image error Oke1 and the Oke2 two image errors because of interval A1 generation appear, i.e. in the cell picture zone.

The center of the first image error Oke1 appears at the position at a distance of o1=Ro1315 ° of Rox θ ox=Ro1 θ with SL.Because the center of the second image error Oke2 and the first image error Oke1 are at a distance of the distance of 2 π Ro1, therefore the second image error Oke2 is located in the position at a distance of 2 π Ro1+Ro1 θ o1=(2 π+θ o1) Ro1 with SL.

Therefore, for the first and second image error Oke1 that will produce because of the interval A1 of OPC 30, among the Oke2 one image error that produces with interval B because of driven roller 80 is in identical position alignment, distance R d θ d from SL to Rke just should with the distance R ox θ ox=Ro1 θ o1 from SL to the first image error Oke1, perhaps identical with distance (2 π+θ o1) Ro1 from SL to the second image error Oke2.

In order to summarize condition recited above, can obtain first equation of following equation set 5.

Rd θ d=(2 π l+ θ ox) Rox (l=1,2,3 ...), (x=1,2,3 ...), and Rd=zRox, (z=2,3,4,5 ...) ... ... ... ... ... ... ... ... ... ... .... 1.

By first equation with Rd=2Ro1 substitution equation set 3, θ o1=2 θ d-2 π is just satisfied in the installation of OPC 30 and driven roller 80.Because θ d=315 °, θ o1=630 ° of-2 π=270 °.That is, when driven roller 80 initial positions are positioned at respect to interval B when+X-axis is changeed 315 ° position clockwise, according to first equation of equation set 5, the interval A1 of OPC 30 is located in the position with respect to moving 270 ° of+y-axis shift, shown in Figure 18 C.Because the position of A1 is scheduled at interval, therefore, the phase place place in that the positioning element 33b of driven coupler changes 45 ° counterclockwise can easily adjust interval A1 to satisfy θ o1=270 °.

When OPC 30 and driven roller 80 were installed to be first equation that satisfies equation set 3, image error Oke2 and Rke be just at identical location overlap, that is, and and with the position of SL at a distance of d=Rd315 °=(2 π+θ o1) Ro1=of Rd θ (2 π+270 °) Ro1.Therefore, overlapping double exposure Te1 and non-overlapped image error Oke1 that an image error Oke2 and Rke are only arranged in the K color image.

As mentioned above, when an OPC 30 and driven roller 80 are configured such that image error can be overlapping, in the image error that the interval A2 of adjacent OPC 40 causes one just can with the image error overlaid of driven roller 80.In other words, shown in Figure 18 C, because of also being Sd=2Ro2, satisfy o1=270 ° of θ o2=θ according to first equation of equation set 3 at C look OPC 40.Therefore, when the interval A2 of C look OPC 40 be positioned at relatively+when Y-axis is changeed 270 ° position counterclockwise, the center of the second image error Oce2 that produces because of interval A2 just with the SL position of Rd θ d apart, shown in Figure 18 D.Therefore, the image error of C look OPC 40 is just overlapping at the same position place with overlapping imaging error Te1.

Because do not consider the distance between adjacent OPC 30 and 40 here, image error Rke that just needn't overlapping driven roller 80 and other image errors Oke1 and Oce1.For the image error Oke1 that will produce because of interval A1 and Oke2 with overlapping because of the image error Oce1 and the Oce2 of interval A2 generation, OPC 30 and 40 is configured to satisfy first equation of equation set 2.For detailed explanation, OPC 30 and 40 is configured to locate to satisfy first equation of equation set 3.Therefore, shown in Figure 18 C, can understand θ o2=θ o1=α 2=α 1.In first equation with α 2=α 1 substitution equation 2 or 3, just satisfy L1=2 π lRo1.Wherein because l is an integer, the distance L 1 between center C 1 and the C2 just is set to the integral multiple of the girth of OPC 30.When l=1, the transfer printing point Po2 of the OPC 40 of C color image is located in the position of moving S1 with the 70 starting point Po1 from the K color image.Therefore, the image error that produces because of interval A1 and A2 (Oke1, and Oke2) (Oce1, Oce2) overlapping in identical position.Because OPC 30 and 40 is installed into first equation that satisfies equation set 5, overlapping image error Ok2, Oce2 are just overlapping with the image error Rke that the interval B of driven roller 80 produces.

Should be appreciated that from top explanation, when the radius of driven roller 80 be OPC radius be equal to, or greater than 2 integral multiple the time, satisfy first equation of equation set 5 by system is set, in a plurality of image errors that produce because of OPC one just can with the image error overlaid of driven roller 80.Other OPC is set in the same way, and the system of setting makes its first equation that satisfies equation set 3, just can be with one in a plurality of image errors that produced by the corresponding OPC image error overlaid with driven roller 80.

During first equation of the equation set 2 that is set to satisfy when system, just can be superimposed by two

OPC

30 and 40 image errors that produce.Like this, the image errors because of

OPC

30 and 40 generations just can be greatly diminished.

Be that example has illustrated that the image error that produced by driven roller 80 and two OPC30 and 40 image errors that produced are overlapping with OPC 30 and 40.Be appreciated that if with one among the OPC 30 to 60 first equation of being arranged to satisfy equation set 5, can obtain to reduce the quantity of the image error that selected OPC produces equally.

First equation of equation set 5 and the satisfied simultaneously example of first equation of equation set 2 and 3 have been described.Should be appreciated that at least one that all satisfies in the equation set 2 as

OPC

30,40,50,60, and when satisfying first equation of equation set 5, relevant OPC still can obtain identical effect.For concisely just being not described in detail here.

The size of now explaining driven roller and OPC roller is equal, i.e. the situation of Rd=Rox.The radius deviation of hypothesis driven roller and OPC roller is equal, i.e. the situation of δ D=δ o.

With reference to Figure 19 A, Rd=Rox=Ro1.When driven roller 80 rotated one time, relevant OPC 30 also rotated once.Suppose twice formation of OPC 30 rotation, one cell picture, because of the interval A1 of OPC 30 produces two image error Oke1 and Oke2 on K color element image, shown in Figure 19 B.Because the interval A1 of OPC 30 is changeing on the phase place of θ o1 counterclockwise with respect to+Y-axis, the center of the first image error Oke1 is located in and begins the transfer printing point Po1 position of Ro1 θ o1 apart.The second image error Oke2 is located in the position at a distance of 2 π Ro1+Ro1 θ o1 with Po1.Two image error Rke1 that produced by the interval B of driven roller 80 and Rke2 are positioned at a certain position of K color element image.Still with reference to Figure 19 A, is changeing on the phase place of θ d clockwise with respect to+X-axis at the center of the interval B of driven roller 80.Therefore, the center of the first image error Rke1 that produces because of interval B is located in the position at a distance of Rd θ d with Po1, and the center of the second image error Rke2 is located in the position at a distance of 2 π Rd+Rd θ d with Po1, shown in Figure 19 B.

Thereby the distance between the first image error Rke1 and the Oke1 is exactly d1=Ro1 θ o1-Rd θ d.Equally, the distance between the second image error Rke2 and the Oke2 is exactly d1=Ro1 θ o1-Rd θ d.

Because Rd=Ro, when OPC 30 and driven roller 80 are set to satisfy condition d1=0, that is, condition Ro1 θ o1-Rd θ d, the image error Oke1 of OPC 30 and Oke2 just can be overlapping respectively with the image error Rke1 and the Rke2 of driven roller 80.Shown in Figure 19 A, θ d=225 ° and θ o1=315 °.Therefore, when the image error Rke1 of the image error Oke1 of OPC30 and Oke2 and driven roller 80 and Rke2 were overlapping, OPC30 just was configured to o1=225 ° of θ d=θ, shown in Figure 19 C.Because the interval A1 of OPC 30 be set in advance with the positioning element particular phases place of driven coupler, in the specific embodiment of the invention, the interval A1 of OPC 30 just is set at from+Y-axis and is rotated counterclockwise 225 °.With reference to Figure 19 D, the radial displacement δ o of OPC 30 and driven roller 80 appears at identical pattern period with δ d and is with on 70, and overlaps each other.Therefore, have only the double exposure image of image error Oke1 and Oke2 and the double exposure image of Rke1 and Rke2 to appear on the cell picture, reduce the quantity of image error with this.Like this, the aliasing error Te3 of Oke1 and Rk1 is just only arranged in the cell picture zone, and the aliasing error Te4 of Oke2 and Rke2.

And when OPC 30 is set to driven roller 80 is arranged to satisfy second condition of equation set 5, if during condition that is configured to satisfy in equation set 2 or 3 among the adjacent OPC 40-60, the image error that relevant OPC produced just can be with respect to aliasing error Te3 and Te4 and is overlapping.Just as described, here for concisely repeating no more according to Fig. 6 A to 16.

The OPC roller now is described greater than driven roller, i.e. the situation of Rd＜Rox.The radius deviation of supposing OPC and driven roller once more is equal, i.e. δ D=δ 0.Because Rd＜Rox, the swing circle of driven roller 80 is than

OPC

30,40 in the unit interval, and 50,60 swing circle is short.Thereby the image error that driven roller 80 causes in the cell picture zone is more than the image error of OPC.If one in a plurality of image errors that driven roller 80 produces in the cell picture zone with overlapping by the relevant image error that OPC produced, the sum of image error just can reduce.For this reason, system is set to satisfy the 3rd equation of equation set 5.Situation when the radius R ox that has explained OPC in the embodiments of the invention is the twice (c=2) of radius R d of driven roller 80.The cell picture of supposing a certain color is by driven roller 80 rotation four times, and corresponding OPC rotates twice formation.Therefore, the image error that driven roller 80 and OPC produce always has 6, comprises four image errors that produced by driven roller 80 and two image errors that produced by OPC.

With reference to Figure 20 A, explain the situation of the 3rd equation that does not satisfy equation set 3.The position at the center of the interval B of driven roller 80 is in θ d=225 ° position with respect to+X-axis.If the transfer printing of K look begins, driven roller 80 rotations four times, K color element image is transferred to be with on 70, shown in Figure 20 B.Because of four image error Rke1 that interval B produces, Rke2, Rke3 and Rke4 occur in the cell picture zone with interval 2 π Rd.The position at a distance of d=Rd225 ° of Rd θ with beginning transfer printing point Po1 takes place in initial image error Rke1.Other image error Rke2, Rke3 and Rke4 appear at and put the position of Po1 at a distance of (2 π h+ θ d) Rd (h=1,2,3) in proper order.

OPC 30 is set in distance+Y-axis to be changeed θ o1=45 ° counterclockwise and locates.Be transfer printing K color element image, twice of OPC 30 rotation.Like this, two image error Oke1 that produce because of interval A1 and Oke2 just appear in the K color element image-region on the position of 2 π Ro1, shown in Figure 20 B.The first image error Rke1 occurs in 70 from beginning the position that transfer printing point Po1 moves o1=Ro145 ° of Ro1 θ.Thereby the distance between the first image error Oke1 and the Rke1 is d2=Ro1 (0.5 θ d-θ o1)=Ro1 (112.5 °-45 °)=Ro167.5 °.

Thereby, be overlapping two image error Oke1 and Rke1, from Po1 to image error Oke1 and the distance of Rke1 should be identical.When driven roller 80 is set in advance, the Rd θ d=Ro1 that need satisfy condition (45 °+67.5 °).The 3rd equation of equation set 5 satisfies by OPC 30 being arranged on A1 at interval is positioned at be rotated counterclockwise 112.5 ° position from+Y-axis, shown in Figure 20 C.In Figure 20 D, two image error Oke1 and Rke1 are centered close to identical position, that is, the center is set at Po1 and aims at a distance of o1=Ro1112.5 ° of position of Rd θ d=Ro1 θ.Overlapping by the second image error Oke2 that interval A1 produces with the 3rd image error Rke3 that produces by interval B.Therefore, 6 image errors in the K color element image-region just are reduced for 4 image errors, thereby have weakened the influence of image error.

Can be further by the collaborative image error that is caused by OPC that reduces of other OPC and an OPC be set.That is to say that relevant OPC can be set to satisfy at least one in the condition of equation set 2-4, and satisfy the condition of equation set 5.In this case, at least one in the image error that is produced by driven roller 80 can be overlapping with the image error of OPC, and the image error that is produced by OPC also can overlap each other.Therefore, the quantity of image error just is lowered manyly.

How to the following describes in cell picture, at least one in identical position makes the image error of image error and at least two OPC of driven roller 80 is overlapping.In an embodiment of the present invention, example all image errors of a plurality of

OPC

30,40,50,60 be superimposed, and the overlapping error of

OPC

30,40,50,60 is overlapping with the image error of driven roller 80.That is,

OPC

30,40, and 50,60 radius is identical.

At first, with reference to Figure 21 A, the radius R d of driven roller 80 is than OPC 30,40, and 50,60 radius R ox is big.OPC 30,40, and 50,60 separately radiuses are identical Rox=Ro.OPC 30,40, the distance L 1 among 50,60 the center C 1-C4, and L2, L3, L4, L5 and L6 are configured to satisfy each condition of equation set 1.Like this, OPC 30,40, and 50,60 position just is set at satisfies L1=L2=L3=SD (2 π Rd).Under these conditions, the position that the image error that produces because of the interval B of driven roller 80 occurs just with OPC 30,40,50,60 are transferred to cell picture with the double exposure on 70 in identical position.Shown in Figure 21 B, if the rotation of driven roller 80 once can form the cell picture zone, because of the color error Rke that interval B produces, Rce, Rme, the center of Rye is located in the cell picture zone and the position of initial SL at a distance of Rd θ d (315 °).Because L1=L2=L3=Sd, by OPC 30,40, the double exposure of 50,60 transfer printings only has only one by image error Rke at the colour cell image-region on 70, Rce, Rme, the aliasing error Rte that Rye is overlapping.At last, satisfying all conditions of equation set 1, the image error that produces because of the interval B of driven roller 80 just can be lowered to 1/4th, so picture quality is enhanced by tectonic system.

As mentioned above, because of losing each

OPC

30,40,50,60 of circular error radial displacement is arranged all.OPC30,40,50,60 interval A1, A2, A3 and A4 can cause image error.For overlapping because of A1, A2, the image error that A3 and A4 cause, in Figure 21 A, OPC is arranged to satisfy the condition of equation set 2 and equation set 3.In brief, satisfy L1=L2=L3, and the radius of

OPC

30,40,50,60 is identical.OPC30, maximum radial displacement+δ 0 of 40,50,60 all are positioned at counterclockwise from+Y-axis changes 270 ° same phase counterclockwise.Aforesaid structure, when driven roller 80 rotated one time,

OPC

30,40,50,60 rotations twice, but generation unit image-region.

In each

OPC

30,40,50,60, produce two image errors, because of

OPC

30,40,50, the 60 first image error Oke1 that produce, Oce1, Ome1, the center of Oye1 is in the position of changeing Ro270 ° from initial SL, shown in Figure 21 C.Because of

OPC

30,40,50, the 60 second image error Oke2 that produce, Oce2, Ome2, the center of Oye2 is in the position of changeing Ro (2 π+270 °) from initial SL.The coloured image of

former cause OPC

30,40,50,60 double exposures has Oke1, Oce1, Ome1, Oye1 and Oke2, Oce2, Ome2, Oye2, totally 8 image errors.When system is configured to satisfy equation set 2-4, during the condition of equation set 3 and equation set 4, just only the first image error Oke1 appears, Oce1, Ome1, the aliasing error Ote1 of Oye1 and the second image error Oke2, Oce2, Ome2, the aliasing error Ote2 of Oye2.Like this, the quantity of image error can be lowered to 1/4th of the image error quantity that produces when not according to the relative position of equation set 2 control OPC.

By

OPC

30,40,50, the 60 aliasing error Ote1 that produce can appear at the position different with the aliasing error Rte of driven roller 80 above-mentioned with Ote2.When one among the aliasing error Ote1 of aliasing error Rte and

OPC

30,40,50,60 and the Ote2 when overlapping, the quantity of the image error in the cell picture zone can also be lowered.For this reason, can be arranged to satisfy the condition of first equation in the equation set 5, shown in Figure 21 A.That is Rd=2Rox=2Ro1=2Ro2=2Ro3=2Ro4.That is, θ ox=θ o1=θ o2=θ o3=θ is o4=270 °.Therefore, SL in the heart distance R d θ d in the Rte is just identical with SL in the heart distance R o (2 π+270 °) in the Ote2.In other words, Rd=2Ro, and during d=2Ro315 °=Ro of Rd θ (2 π+270 °), two aliasing error Ote2 and Rte are just overlapping at a distance of the distance of Rd θ d with SL.

During Rd=2Ro, when system is set to satisfy all conditions among equation set 1 and the equation set 2-4 and satisfies first equation of equation set 5, OPC 30 is just only arranged in the cell picture zone, 40,50,60 the first aliasing error Ote1 and

OPC

30,40, the aliasing error Te5 of 50,60 the second aliasing error Ote2 and the aliasing error Rte of driven roller 80 is shown in Figure 21 D.At last, 12 image errors in the cell picture zone comprise that 4 image errors of driven

roller

80 and 8 image errors of

OPC

30,40,50,60 just can be lowered to 2 image errors.The quantity of image error is significantly reduced, and picture quality is improved.

Secondly, work as Rd=Rox, equation set 1, equation set 2-4 and equation set 5 all satisfy.In this case, OPC 30,40, and 50,60 radius is identical, Rox=Ro.With reference to Figure 22 A, the interval B of driven roller 80 is just changeing the phase place of θ d clockwise from+X-axis.In an embodiment of the present invention, θ d=315 °.OPC 30,40,50,60 center C 1, and C2, C3, the distance of C4 is L1=L2=L3=2 π Rd=Sd.OPC30, in the heart distance is set to equal the integral multiple of the girth of driven roller 80 in 40,50,60.Such system can satisfy equation set 1.For ease of understanding the present invention, suppose the cell picture zone in driven roller 80 formation that rotates a circle, B is at OPC 30,40 at interval, and 50,60 identical separately phase places exert an influence.Particularly, the driven roller 80 among Figure 22 A need rotate four circles transfer printing OPC 30,40,50,60 double exposure coloured image and form final full-colour image.Shown in Figure 22 B, because of the image error Rke that interval B produces on colored double exposure image, Rce, Rme, the center of Rye is aimed at a distance of the position of d=Rd315 ° of Rd θ with initial SL.As OPC 30,40,50,60 when being configured to satisfy equation set 1, ignores the number of revolutions of driven roller 80, because of all image error Rke that interval B produces, and Rce, Rme, Rye are by OPC30, and 40,50,60 carry out all appearing at identical position during the image transfer printing.Thereby, a superimposed images Rte only takes place.

OPC

30,40, and 50,60 are installed into and satisfy equation set 2.Specifically, be exactly

OPC

30,40,50,60 are installed into and make

OPC

30,40,50,60 separately interval A1, A2, A3 and A4 are positioned at from transfer printing starting point Po1, Po2, Po3, Po4 rotate identical angle place in the counterclockwise direction, that is, and and position phase α 1=α 2=α 3=α 4.For understanding the present invention, α 1 to α 4 is set to 315 °, and

supposition OPC

30,40,50,60 rotates a circle and produces the colour cell image.With reference to Figure 22 C, because of

OPC

30,40,50,60 interval A1, A2, the image error Oke that A3 and A4 cause appears at the cell picture zone from 1=Ro315 ° of initial SL distance R o α to the center of Oye.Therefore, through

OPC

30,40,50, the 60 colour cell image-regions that are transferred to the double exposure on 70 only have the aliasing error Ote of image error Oke to Oye.Aliasing error Ote is positioned at SL and locates at a distance of Ro315 °.

The system of Figure 22 A is set to satisfy second condition of equation set 3.That is, Rd=Rox, and the θ o1 of each

OPC

30,40,50,60 (=α 1), θ o2 (=α 2), θ o3 (=α 3) and θ o4 (=α 4) equal 315 °, also equal θ d.

Therefore, the image error that causes because of the interval B of driven roller 80 with because of OPC 30,40,50,60 separately interval A1, A2, the image error that A3 and A4 cause is overlapping.Simultaneously, as Figure 22 B explanation, because of the image error Rke that driven roller 80 causes, Rce, Rme, Rye and aliasing error Rte are at identical location overlap.Because of OPC 30,40,50,60 the image error Rke that causes, Rce, Rme, Rye and aliasing error Ote are also at identical location overlap.For this reason, system also satisfies the condition of second equation of equation set 5, allows two aliasing error Rte and Ote at identical location overlap.Thereby, shown in Figure 22 D, the last aliasing error Te6 that is produced by two aliasing error Rte and Ote is just only arranged in the cell picture zone.Last aliasing error Te6 be centered close to SL at a distance of the distance of Rd θ d=Ro θ o1=Ro α 1.Under the condition of Rd=Ro, when second condition of equation set 1, when equation set 2-4 and equation set 5 all satisfy simultaneously, just can be in the cell picture zone overlapping more image error.Therefore, the quantity of image error just can reduce, and picture quality just can improve, and the fiduciary level of product just can promote.

The 3rd, with reference to Figure 23 A, describe when the OPC roller greater than driven roller, promptly when Rox=hRd (h=2,4,6 ...) and the time situation.For ease of understanding the present invention, the radius R d of driven roller 80 is twices of the radius R ox of OPC in the example.The quantity of relevant OPC is 4, and the radius of

OPC

30,40,50,60 is Rox=Ro1=Ro2=Ro3=Ro4.

OPC 30,40,50,60 center C 1, and C2, C3, the distance between the C4 is L1=L2=L3=2 * 2 π Rd=2Sd.Therefore, when driven roller 80 rotated for two weeks, OPC 30,40, and 50,60 rotate a circle separately.Hypothesis driven roller two weeks of 80 rotations produce the cell picture of a certain color, and the interval B of driven roller 80 just produces the influence of two image errors on the cell picture of this color, shown in Figure 23 B.Because OPC30, in the heart distance is the integral multiple of the girth of driven roller 80 in 40,50,60, the first image error Rke1 that every kind of color produces to the center of Rye1 just with the initial SL position of Rd θ d apart.The second image error Rke2 to the center of Rye2 just with the position of initial SL at a distance of 2 π Rd+Rd θ d.If θ d=180 °, the first image error Rke1 to the center of Rye1 just with the position of d180 ° of initial SL distance R, as a superimposed images Rte1.The second image error Rke2 to the center of Rye2 just as a superimposed images Rte2 with the position of initial SL at a distance of 2 π Rd+Rd180 °=Rd (2 π+180 °).

Define in first and second condition as equation set 2,

OPC

30,40,50,60 center C 1, and C2, C3, the distance between the C4 satisfies L1=L2=L3=2 π Ro.Because α 1=α 2=α 3=α 4=θ is o1, because of

OPC

30,40,50,60 interval A1, A2, the image error Oke that A3 and A4 cause just appear to the center of Oye in the cell picture zone and the position of SL at a distance of Ro θ o1, shown in Figure 23 C.That is, θ o1=α is 1=270 °.Therefore,

OPC

30,40, and 50, the 60 image error Oke that produce just appear at SL with an aliasing error Ote to Oye and locate at a distance of Ro279 °.

Among Figure 23 A, system is set to satisfy the 3rd equation of equation set 5.Because 2Rd=Rox, by the 3rd equation of substitution equation set 5, (2 π θ d) Rd=Rox θ ox=2Rd θ ox.Because θ d=180 °, (2 π+180 °) Rd=2Rd θ ox.As seen, above-mentioned equation can be replaced by (2 π+180 °)=θ ox, and θ ox=270 °.Because OPC 30,40 among Figure 23 A, o4=270 ° of 50,60 θ o1=θ o2=θ o3=θ, OPC 30,40, and 50,60 satisfy the 3rd equation of equation set 5.After satisfying the 3rd equation of equation set 5, with reference to above-mentioned Figure 23 B and 23C, energy among two aliasing error Rte1 and the Rte2 and final aliasing error Te7 overlap final aliasing error Te7 and the equitant same position of other aliasing errors Ote place shown in Figure 23 D.Because by OPC 30,40, the center of 50, the 60 overlapping imaging error Ote that cause with SL at a distance of the position of Ro θ o1=(2 π+θ d) Rd, final aliasing error Te7 is located in the position at a distance of Ro θ o1=(2 π+θ d) Rd with SL.At last, shown in Figure 23 D, last colour cell image just only has aliasing error Rte1 and final aliasing error Te7.

In the embodiment of example of the present invention, described by OPC 30, the main image error that 40,50,60 the mistake circular error and the mistake circular error of driven roller 80 cause, and do not consider the influence of backing roll 91, wherein

OPC

30,40, and 50,60 transfer images to and are with on 70 driven roller 80 rotating bands 70.Therefore, the influence of backing roll 91 has here just no longer illustrated.Should be appreciated that driven roller 80 and backing roll (driven voller) 91 is interchangeable each other.

Set forth as top, according to the manufacture method of roller of the present invention and roller, the positioning element that roller is assembled into its driven coupler is positioned in the maximum radial displacement position at angle with respect to roll body (drum body).Therefore, can control the influence of the radial displacement of the roller that is adopted.

The driver element of image-forming apparatus according to the present invention can be controlled the aligning of OPC based on a certain criterion, controls the influence that the radial displacement because of band radial displacement of backing roll and/or OPC produces like this.

In addition, imaging device can be controlled the position of the image error that produces because of the mistake circular error of driven roller, and is reduced in the quantity of the image error in the image of last double exposure.Therefore, can improve picture quality, and promote reliability of products.

Especially, frequency can be reduced, and the radius of OPC and driven roller need not be considered because of the image error of driven roller and/or OPC generation.

Top embodiment and advantage only are examples, and should not be construed as limitation of the present invention.The present invention can easily be applied in the device of other types.In addition, the description of embodiments of the invention is only used for explanation, and does not limit the scope of claim, and multiple modification, improvement and variation are obvious to those skilled in the art.

Claims

1, a kind of roller comprises:

A roll body that has radial displacement along peripheral direction; With

With the driven coupler that a termination of described roll body is closed, it is used for driving the coupler complementary fit with one of transmission driving force,

Wherein, described roll body has the mark that is formed on the precalculated position, and this mark is used to indicate radial displacement.

2, roller according to claim 1, wherein, described driven coupler comprises location parts that are used for definite position that engages with described driving coupler, and

Described roll body engages with described driven coupler, makes described positioning element keep a predetermined angular with respect to described mark.

3, roller according to claim 1, wherein, described mark is arranged to become a predetermined angular with the position of the maximum radial displacement of described roll body.

4, a kind of image carrier that is used in the imaging device comprises:

A drum body that has radial displacement along peripheral direction; With

With the driven coupler that a termination of described bulging body is closed, it is used for driving the coupler complementary fit with one of transmission driving force,

Wherein, described bulging body has the mark that is formed on the precalculated position, and it is used to indicate radial displacement.

5, image carrier according to claim 4, wherein, described mark is arranged to become a predetermined angular with respect to the position of maximum radial displacement.

6, image carrier according to claim 4, wherein, described driven coupler comprises location parts that are used for definite position that engages with described driving coupler, and

Described driven coupler engages with described bulging body, makes described positioning element keep a predetermined angular with respect to described mark.

7, image carrier according to claim 6, wherein, described driven coupler comprises with recessed or protruding mode and forms the non-circular coupling access component at one end gone up so that engage with described driven coupler and accept driving force, and

Described positioning element extends from described coupling access component on the radial direction of described driven coupler.

8, a kind of method of making roller, described roller comprise along peripheral direction have radial displacement a roll body and with the driven coupler that a termination of described roll body is closed, said method comprising the steps of:

Find out an interval of the radial displacement maximum of stating roll body in this place; And

According to the described interval of finding out the attitude of described driven coupler is set as one man, and engages described driven coupler and described roll body.

9, method as claimed in claim 8, wherein, the described step of finding out the interval with maximum radial displacement comprises following step:

By measuring an end of described roll body, find out the point of a maximum radial displacement; With

Form a mark on described roll body, this mark is used to indicate the point of the described maximum radial displacement of finding out.

10, method as claimed in claim 8, wherein, the step of the described driven coupler of described joint comprises step: described driving coupler is assembled on the described roll body, makes the positioning element of described driven coupler keep a predetermined angular with respect to the point of described maximum radial displacement and determine the relative position of the joint of described driven coupler and described driving coupler.

11, method as claimed in claim 7, wherein, the step of the described driven coupler of described joint comprises following step:

At the described roll body of one first anchor clamps upper support, the point that makes described maximum radial displacement becomes predetermined angular location with respect to the reference coordinate axle;

In the described driven coupler of one second anchor clamps upper support, make described driven coupler become predetermined angular location with respect to the reference coordinate axle;

Described first and second anchor clamps are close to each other and make described driven coupler engage with described roll body.

12, a kind of driver element of imaging device comprises:

Be used for driving a plurality of first main drive gears and a plurality of a plurality of second main drive gears of one that are used to drive a plurality of backing rolls with a plurality of image carriers of predefined procedure setting, described backing roll supports a band and turns round on described a plurality of image carriers,

Wherein, the distance between at least two the rotation center in a plurality of first driven wheels be one girth in the described backing roll positive integer doubly.

13, driver element as claimed in claim 12, wherein, each in the distance between the rotation center of a plurality of first main drive gears be one girth in the described backing roll positive integer doubly.

14, driver element as claimed in claim 12, wherein, one in the described backing roll is driven roller, described driven roller is accepted driving force when engaging with described second main drive gear.

15, driver element as claimed in claim 12, wherein, a roller in the described backing roll is a roller that has maximum radial displacement relatively greatly when its radius when its peripheral direction changes.

16, driver element as claimed in claim 12, wherein, described first main drive gear comprise with respect to the direction of tape travel with predefined procedure be provided with first to the 4 wheel driven moving gear, described first satisfies in the equation 1 at least one to the 4 wheel driven moving gear:

(equation 1)

L1＝l·Sd·(1±0.05)(l＝1，2，3，...)........................1

L2＝m·Sd·(1±0.05)(m＝1，2，3，...)........................2

L3＝n·Sd·(1±0.05)(n＝1，2，3，...)........................3

L4＝o·Sd·(1±0.05)(o＝1，2，3，...)........................4

L5＝p·Sd·(1±0.05)(p＝1，2，3，...)........................5

L6＝q·Sd·(1±0.05)(q＝1，2，3，...)........................6

Wherein, L1 is the distance between the center of first, second driven wheel,

L2 is the distance between the center of second, third driven wheel,

L3 is the 3rd, the distance between the center of 4 wheel driven moving gear,

L4 is the distance between the center of the first, the 3rd driven wheel,

L5 is first, the distance between the center of 4 wheel driven moving gear,

L6 is second, the distance between the center of 4 wheel driven moving gear and

Sd is the girth of the described roller in the described backing roll.

17, driver element as claimed in claim 16, wherein, first to the 4th gear is installed into and satisfies equatioies all in the equation 1.

18, driver element as claimed in claim 16, wherein, first is installed into to the 4 wheel driven moving gear and satisfies L1=L2=L3.

19, driver element as claimed in claim 18, wherein, first is installed into to the 4 wheel driven moving gear and satisfies L1=L2=L3=lSd.

20, driver element as claimed in claim 12, wherein, the radius of described backing roll equals the radius of described image carrier.

21, driver element as claimed in claim 12, wherein, also comprise a plurality of driving coupler, described driving coupler is arranged on each rotation center in described a plurality of first main drive gear so that engage to transmit driving force with in described a plurality of image carriers each.

22, driver element as claimed in claim 21, wherein, described driving coupler comprises:

One coupling access component, it is configured to have each the corresponding noncircular cross section in the driven coupler with an end that is arranged on each image carrier; With

One location parts, it is arranged on a side of described coupling access component so that the position of determining to engage makes described driving coupler engage described driven coupler with fixing attitude.

23, driver element as claimed in claim 22, wherein, described coupling access component is to constitute one of noncircular cross section from a concave end of described coupler to couple recess, and described positioning element is the recess from the recessed predetermined depth in inboard of described coupling access component.

24, driver element as claimed in claim 23, wherein, described driven coupler comprises from an end to the rotation center projection, and is arranged on the described bottom surface that couples recess and is used for and a described axis hole that is coupling and closes.

25, driver element as claimed in claim 22, wherein, described coupling access component is to constitute one of noncircular cross section from end extension to couple protuberance, and described positioning element is a protuberance that extends from the described outside that couples protuberance.

26, a kind of imaging device comprises:

A plurality of image carriers with the predefined procedure setting;

Contact an intermediate transfer medium of running with in described a plurality of image carriers each; With

Be used to drive a plurality of backing rolls of described intermediate transfer medium,

Wherein, the distance between the rotation center of at least two image carriers be a backing roll girth positive integer doubly.

27, imaging device as claimed in claim 26, wherein, described image carrier comprises first to the 4th image carrier that the direction with respect to the running of described intermediate transfer medium is provided with predefined procedure, and described first to the 4th image carrier satisfies at least one in the equation 1:

(equation 1)

L1＝l·Sd·(1±0.05)(l＝1，2，3，)..................1

L2＝m·Sd·(1±0.05)(m＝1，2，3，)..................2

L3＝n·Sd·(1±0.05)(n＝1，2，3，)..................3

L4＝o·Sd·(1±0.05)(o＝1，2，3，)..................4

L5＝p·Sd·(1±0.05)(p＝1，2，3，)..................5

L6＝q·Sd·(1±0.05)(q＝1，2，3，)..................6

Wherein, L1 is the distance between the center of first, second driven wheel,

L2 is the distance between the center of second, third driven wheel,

L3 is the 3rd, the distance between the center of 4 wheel driven moving gear,

L4 is the distance between the center of the first, the 3rd driven wheel,

L5 is first, the distance between the center of 4 wheel driven moving gear,

L6 is second, the distance between the center of 4 wheel driven moving gear and

Sd is the girth of the described roller in the described backing roll.

28, image-generating unit as claimed in claim 27, wherein, described image carrier is installed into and satisfies equatioies all in the equation 1.

29, imaging device as claimed in claim 27, wherein, described image carrier is installed into and satisfies L1=L2=L3.

30, imaging device as claimed in claim 29, wherein, described image carrier is installed into and satisfies L1=L2=L3, and L1, L2, L3 be Sd positive integer doubly.

31, imaging device as claimed in claim 29, wherein, described a plurality of backing rolls comprise a driven roller and an idler roller, and described driven roller is used for along with transmitting driving force rotation thereon and driving described intermediate transfer medium, the driven rotation of described idler roller and support described intermediate transfer medium, and

Sd defines the girth of described driven roller.

32, imaging device as claimed in claim 26 wherein, also comprises a driver element, and it is used to drive described image carrier and described backing roll.

33, imaging device as claimed in claim 32, wherein, described driver element comprises:

One first driver element, it is used for driving simultaneously described a plurality of image carrier; With

One second driver element, it is used for of the described a plurality of backing rolls of individual drive.

34, imaging device as claimed in claim 33, wherein, described first driver element comprises:

A plurality of driven wheels, it is configured to corresponding with in described a plurality of image carriers each, and the ground rotation together that is relative to each other; With

One first CD-ROM drive motor, it is used to driving force is provided so that drive described a plurality of driven wheel simultaneously.

35, imaging device as claimed in claim 34, wherein, described second driver element comprises:

One second CD-ROM drive motor; With

A driven wheel, its with described backing roll in one engage and by described second drive motor.

36, imaging device as claimed in claim 34, wherein, each driven wheel and each image carrier their respective end portions comprise one drive coupler and with a driven coupler of described driving coupler complementary fit.

37, imaging device as claimed in claim 36, wherein, described driving and driven coupler comprise in their end:

Coupling access component, it is arranged to noncircular cross section and cooperation complimentary to one another;

Positioning element, its side from each coupling access component extends into a predetermined configuration, to determine the joint attitude of described driving and driven coupler.

38, imaging device as claimed in claim 27, wherein, described image carrier has the radial displacement of change in radius on peripheral direction, and has an at interval A1, A2, A3 and A4, described interval has the maximum radial displacement in precalculated position, and described first to the 4th image carrier is installed into one that satisfies among the equation 2-1:

(equation 2-1):

{2π·m+(α3-α1)}·Ro·(1±0.05)＝L1+L2，(m＝0，1，2，...)，(Ro＝Ro1＝Ro3)............................................................................②

{2π·n+(α4-α1)}·Ro·(1±0.05)＝L1+L2+L3，(n＝0，1，2，...)，(Ro＝Ro1＝Ro4)..........................................................................③

39, imaging device as claimed in claim 38, wherein, described image carrier satisfies L1=L2=L3.

40, imaging device as claimed in claim 38, wherein, described image carrier satisfies L1=L2=L3, L1 wherein, L2 and L3 be Sd positive integer doubly.

41, imaging device as claimed in claim 38 wherein, also comprises a driver element, is used to drive described image carrier and backing roll, and

Each described image carrier at one end has a driven coupler, and this driven coupler engages with described driver element and accepts driving force.

42, imaging device as claimed in claim 41, wherein, each described driven coupler comprises location parts that are used for determining the position that engages with respect to described driver element, and

Described driven coupler is joined so and makes the interval A1 of each image carrier, A2, and A3 and A4 form a predetermined angular with respect to described positioning element.

43, imaging device as claimed in claim 41, wherein, described driver element comprises:

One first driver element, it is used for driving simultaneously described first to the 4th image carrier; With

One second driver element, it is used for the described backing roll of individual drive.

44, imaging device as claimed in claim 43, wherein, described first driver element comprises:

A plurality of driven wheels, it is configured to corresponding with described a plurality of image carriers respectively, the rotation together that is relative to each other, and each driven wheel at one end has a driven coupler to engage with described driven coupler; With

One first CD-ROM drive motor, it is used to provide driving force to drive described a plurality of driven wheel simultaneously.

45, imaging device as claimed in claim 38, wherein, described first and second image carriers are installed into first equation that satisfies among the equation 2-1, and satisfy α 1=α 2.

46, imaging device as claimed in claim 38, wherein, the described first and the 3rd image carrier is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 3.

47, imaging device as claimed in claim 38, wherein, the described first and the 4th image carrier is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 4.

48, imaging device as claimed in claim 38, wherein, described first to the 4th image carrier is installed into all equatioies that satisfy among the equation 2-1, and satisfies α 1=α 2=α 3=α 4.

49, imaging device as claimed in claim 27, wherein, described image carrier has the radial displacement of change in radius on peripheral direction, and has an at interval A1, A2, A3 and A4, described interval has the maximum radial displacement in precalculated position, and in described first to the 4th image carrier at least two are installed into one that satisfies among the equation 2-2:

Equation 2-2:

{2π·l+(α2-α1)}·Ro·(1±0.05)＝L1，(l＝0，1，2，...)，(Ro＝Ro1＝Ro2)......①

{2π·m+(α3-α2)}·Ro·(1±0.05)＝L2，(m＝0，1，2，...)，(Ro＝Ro2＝Ro3)?....?②

{2π·n+(α4-α3)}·Ro·(1±0.05)＝L3，(n＝0，1，2，...)，(Ro＝Ro3＝Ro4) .. ③

Wherein, α 1 on the reverse rotation direction of described first image carrier from position that the transfer printing of described first image carrier begins to the measured angle in the center of described interval A1,

α 4 on the reverse rotation direction of described the 4th image carrier from the position that the transfer printing of described the 4th image carrier begins the angle measured to the center of described interval A4 and

50, imaging device as claimed in claim 49, wherein, described image carrier satisfies L1=L2=L3.

51, imaging device as claimed in claim 49, wherein, described image carrier satisfies L1=L2=L3, and L1, L2 and L3 be Sd positive integer doubly.

52, imaging device as claimed in claim 49, wherein, described image carrier is installed into all equatioies that satisfy among the equation 2-2, and satisfies α 1=α 2=α 3=α 4.

53, imaging device as claimed in claim 27, wherein, each in the described image carrier all has the radial displacement of change in radius on peripheral direction, and described interval A has the maximum radial displacement of pre-position,

Radial displacement in the described backing roll with change in radius on peripheral direction, and B has the maximum radial displacement at interval,

With reference to based on the rotation center of described backing roll and described image bearing roller predetermined (X, Y) coordinate system,

Described image carrier and described backing roll are installed into one that satisfies in the following equation 3:

Equation 3

Rd·θd＝(2π·l+θox)·Rox·(1±0.05)(l＝1，2，3，...)，(x＝1，2，3，...)，Rd＝z·Rox，(z＝2，3，4，5，...)..........................................................................①

Rd·θd＝Rox·θox·(1±0.05)，Rd＝θox，(x＝1，2，3，...)..............................②

(2π·h+θd)·Rd＝Rox·θox·(1±0.05)，(h＝1，2，3，...)，(x＝1，2，3，...)，Rox＝k·Rd，(k＝2，3，4，5，...)............................................................③

Rox be described (x) individual image carrier radius and

Rd is the radius of described backing roll.

54, imaging device as claimed in claim 53, wherein, described axle+X is defined as the rotation direction of parallel described intermediate transfer medium.

55, imaging device as claimed in claim 53, wherein, when on being centered close to of described interval B+X-axis, described intermediate transfer medium contacts with B at interval and accepts driving force.

56, imaging device as claimed in claim 53, wherein, when on being centered close to of described interval B+X-axis, the velocity variations of described intermediate transfer medium reaches maximal value.

57, imaging device as claimed in claim 53, wherein, big and when being its integral multiple, described image carrier and described backing roll just are set to satisfy first equation of equation 3 when the radius of the described image carrier of radius ratio of described backing roll, wherein this integer is 2 or bigger.

58, imaging device as claimed in claim 53, wherein, when the radius of described image carrier equaled the radius of described backing roll, described image carrier and described backing roll were set to satisfy second equation of equation 3.

59, imaging device as claimed in claim 53, wherein, big and when being its integral multiple when the radius of the described backing roll of radius ratio of described image carrier, described image carrier and described backing roll just are set to satisfy the 3rd equation of equation set 3, and described integer can be 2 or bigger.

60, imaging device as claimed in claim 53 wherein, also comprises one one second driver element that is used for driving one first driver element of described image carrier simultaneously and is used to drive described backing roll.

61, imaging device as claimed in claim 60, wherein, each described image carrier comprises drum body and a driven coupler, described driven coupler and a termination of described bulging body are closed and are accepted driving force to be connected with described first driver element.

62, imaging device as claimed in claim 61, wherein, the bulging body of described each image carrier has a mark that is used to indicate maximum radial displacement interval A.

63, imaging device as claimed in claim 62, wherein, the driven coupler of described each image carrier comprises and is used for determining that one of the position engage with described first driver element locatees parts, and described image carrier is joined so with described driven coupler and makes described positioning element be set up the relative described predetermined angular that is marked as.

64, imaging device as claimed in claim 60, wherein, each described backing roll comprises a roll body, and a driven coupler, a termination of described driven coupler and described roll body is closed to accept the driving force from described second driver element.

65, as the described imaging device of claim 64, wherein, the driven coupler of described each backing roll comprises location parts of the position that is used for determining that described relatively second driver element engages, and described roll body becomes the predetermined angular place to be provided with at described relatively positioning element to be used to identify the mark of B at interval.

66, imaging device as claimed in claim 53, wherein, described image carrier has identical radius.

67, imaging device as claimed in claim 53, wherein, described image carrier is configured to satisfy L1=L2=L3.

68, imaging device as claimed in claim 38, wherein, each in the described image carrier all has the radial displacement of change in radius on peripheral direction, and described interval A has the maximum radial displacement of pre-position,

Radial displacement in the described backing roll with change in radius on peripheral direction, and described interval B have the maximum radial displacement and

With reference to based on the rotation center of described backing roll and described image bearing roller predetermined (X, coordinate system Y),

(equation 3)

(2π·h+θd)·Rd＝Rox·θox·(1±0.05)，(h＝1，2，3，...)，(x＝1，2，3，...)，Rox＝k·Rd，(k＝2，3，4，5，...).................................................................③

Rox be described (x) individual image carrier radius and

Rd is the radius of described backing roll.

69, as the described imaging device of claim 68, wherein, described axle+X is defined as the rotation direction of parallel described intermediate transfer medium.

70, as the described imaging device of claim 68, wherein, when on being centered close to of described interval B+X-axis, described intermediate transfer medium contacts with B at interval and accepts driving force.

71, as the described imaging device of claim 68, wherein, when on being centered close to of described interval B+X-axis, the velocity variations of described intermediate transfer medium reaches maximal value.

72, as the described imaging device of claim 68, wherein, big and when being its integral multiple when the radius of the described image carrier of radius ratio of described backing roll, described image carrier and described backing roll just are set to satisfy first equation of equation 3, and described integer can be 2 or bigger.

73, as the described imaging device of claim 68, wherein, when the radius of described image carrier equaled the radius of described backing roll, described image carrier and described backing roll just were set to satisfy second equation of equation 3.

74, as the described imaging device of claim 68, wherein, big and when being its integral multiple when the radius of the described backing roll of radius ratio of described image carrier, described image carrier and described backing roll just are set to satisfy the 3rd equation of equation 3, and described integer can be 2 or bigger.

75, as the described imaging device of claim 68, wherein, described image carrier is configured to satisfy L1=L2=L3.

76, as the described imaging device of claim 68, wherein, described image carrier is configured to satisfy L1=L2=L3, and L1, L2 and L3 be Sd positive integer doubly.

77, as the described imaging device of claim 68, wherein, also comprise a driver element that is used to drive described image carrier and backing roll, and

Each described image carrier at one end has a driven coupler and accepts driving force to be connected with described driver element.

78, as the described imaging device of claim 77, wherein, each driven coupler comprises location parts that are used for definite position that engages with described driver element, and

Described driven coupler is joined so and makes the interval A1 of each described image carrier, A2, and A3 is relative with A4, and described positioning element forms a predetermined angular.

79, as the described imaging device of claim 77, wherein, described driver element comprises:

One first driver element, it is used for driving simultaneously first to the 4th image carrier; With

80, as the described imaging device of claim 79, wherein, described first driver element comprises:

A plurality of driven wheels, it is arranged to corresponding respectively with a plurality of image carriers and the rotation together that is relative to each other, and each driven wheel has a driven coupler to engage with described driven coupler at one end; With

81, as the described imaging device of claim 68, wherein, described first and second image carriers are installed into first equation that satisfies among the equation 2-1, and satisfy α 1=α 2.

82, as the described imaging device of claim 68, wherein, the described first and the 3rd image carrier is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 3.

83, as the described imaging device of claim 68, wherein, the described first and the 4th image carrier is installed into the 3rd equation that satisfies among the equation 2-1, and satisfies α 1=α 4.

84, as the described imaging device of claim 68, wherein, described first to the 4th image carrier is installed into all equatioies that satisfy among the equation 2-1, and satisfies α 1=α 2=α 3=α 4.

85, a kind of imaging device comprises:

A plurality of image carriers, described image carrier are with the predefined procedure setting, have along the radial displacement of peripheral direction and have A at interval, and described interval A has the maximum radial displacement;

One intermediate transfer medium, its with described a plurality of image carriers in each contact running; With

A plurality of backing rolls, described backing roll are used to guide described intermediate transfer medium running and support described intermediate transfer medium, have the radial displacement of change in radius on peripheral direction, and have B at interval, and described interval B has the maximum radial displacement,

Wherein, with reference to based on the rotation center of described backing roll and described image bearing roller predetermined (X, coordinate system Y),

(equation 3)

Rd·θd＝(2π·l+θox)·Rox·(1±0.05)(l＝1，2，3，...)，(x＝1，2，3，...)，Rd＝z·Rox，(z＝2，3，4，5，...)...........................................................................①

Rd·θd＝Rox·θox·(1±0.05)，Rd＝θox，(x＝1，2，3，...)...............................②

(2π·h+θd)·Rd＝Rox·θox·(1±0.05)，(h＝1，2，3，...)，(x＝1，2，3，...)，Rox＝k·Rd，(k＝2，3，4，5，...)..................................................................③

Wherein, θ d be along (X, Y) coordinate system+angle at the center of the interval B that X-axis records on the reverse rotation direction of described backing roll,

Rox be described (x) individual image carrier radius and

Rd is the radius of described backing roll.

86, as the described imaging device of claim 85, wherein, described axle+X is defined as the rotation direction of parallel described intermediate transfer medium.

87, as the described imaging device of claim 85, wherein, when on being centered close to of described interval B+X-axis, described intermediate transfer medium contacts with B at interval and accepts driving force.

88, as the described imaging device of claim 85, wherein, when on being centered close to of described interval B+X-axis, the velocity variations of described intermediate transfer medium reaches maximal value.

89, as the described imaging device of claim 85, wherein, big and when being its integral multiple when the radius of the described image carrier of radius ratio of described backing roll, described image carrier and described backing roll just are set to satisfy first equation of equation 3, and described integer can be 2 or bigger.

90, as the described imaging device of claim 85, wherein, when the radius of described image carrier equaled the radius of described backing roll, described image carrier and described backing roll just were set to satisfy second equation of equation 3.

91, as the described imaging device of claim 85, wherein, big and when being its integral multiple when the radius of the described backing roll of radius ratio of described image carrier, described image carrier and described backing roll just are set to satisfy the 3rd equation of equation 3, and described integer can be 2 or bigger.

92, as the described imaging device of claim 85, wherein, also comprise a driver element, be used to drive described image carrier and backing roll, and

In the described image carrier each at one end has a driven coupler and accepts driving force to be connected with described driver element.

93, as the described imaging device of claim 92, wherein, each described driven coupler comprises location parts that are used for definite position that engages with described driver element, and

Described driven coupler is joined so and makes the interval A1 of each image carrier, A2, and A3 is relative with A4, and described positioning element forms a predetermined angular.

94, as the described imaging device of claim 92, wherein, described first driver element comprises:

A plurality of driven wheels, it is arranged to corresponding respectively with a plurality of image carriers, and the rotation together that is relative to each other, and each driven wheel has a driven coupler to engage with described driven coupler at one end; With

95, as the described imaging device of claim 92, wherein, described second driver element comprises:

One driven wheel, it is arranged to corresponding with a plurality of backing rolls, and described driven wheel has one and drives coupler and engage with the driven coupler with an end that is arranged on each backing roll at one end; With

One second CD-ROM drive motor, it is used to drive described driven wheel.