GB2317880A - Printer - Google Patents

Abstract

A printer comprises a plurality of sheet feeders with associated hoppers, and a printing mechanism moveable to positions opposite to designated ones of the feeders. The paper feeders are arrayed in horizontal and/or vertical directions or in a matrix.

Description

SLIDING PRINTER BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a meted and apparatus for printing. In a preferred form it concerns a printer having a plurality of paper feeders each including a zipper Thing print sheets of a predetermined size. The printer performs printing while the print sheets are fed one by one from one hopper to the printer.

Description of the Related Art Conventional printers have a plurality of paper feeders each including a hopper holding print sheets of a predetermined size. The printers perform printing while the print sheets are fed one by one from one hopper.

Japanese Patent Application Laid-Open No. 60-148837 discloses, as one of these printers, a printer which has a plurality of paper trays. All the paper trays are moved such that a designated paper tray is positioned opposite to a printing mechanism, and desired print sheet is fed to the printing mechanism.

Japanese Patent Application Laid-Open No. 4-55268 discloses a construction where a paper feed unit receives a print sheet fed from a designated one of a plurality of paper cassettes and conveys the print sheet, and a guide belt guides the print sheet supplied from the paper feed unit. The paper feed unit is moved along the guide belt to the position of the designated paper cassette, and a desired print sheet is supplied to a printing mechanism.

As described above, in the former printer, all the plurality of paper trays, which are heavy due to the weight of the print sheets and they are moved under heavy load.

As it is required to enlarge a drive power source and increase the strength of parts of related mechanisms, manufacturing cost cannot be reduced without difficulty.

In the latter printer, as the paper feed unit is moved along the guide belt, the structure of the mechanism is complicated, and the number of parts of the mechanism is large. When some part is exchanged for new one or some trouble has occurred, exchanging or fixing operation cannot be easily made. Thus, it is difficult to improve maintainability.

Further, these conventional printers both have a paper-conveyance path curved at a small radius of curvature. In use of inflexible print sheet such as a board sheet, reliability of print-sheet conveyance cannot be maintained without difficulty.

SUMMARY OF THE INVENTION The present invention has been made to solve the drawbacks of the above conventional printers, and in preferred embodiments has as its object to provide a printer which holds many types of print sheets and selects sheet upon printing, and which can maintain reliability even in use of an inflexible type print sheet, with reduced manufacturing cost and, further, with improved maintainability. For this purpose, in the printer of the present invention, a printing mechanism is moved to the position of a designated hopper or other storage facility for sheet material. Thus, a sheet-conveyance path need not be curved at a small radius of curvature, and printing is performed with respect to a desired print sheet.

There is one aspect the invention provides a method of printing on sheet material comprising providing a plurality of spatially-distributed sources of different sheet materials, and moving a printing mechanism into operating relationship with a selected one of said sources depending upon which sheet material is to be printed.

In another aspect the invention provides printing apparatus comprising a plurality of spatially-distributed storage means for different sheet materials, a printing mechanism for receiving sheet material from said storage means and for printing on said sheet material, and means for moving the print mechanism into operative relationship with a selected one of said storage means depending on which sheet material is to be printed.

More specifically, the foregoing object can be attained by providing a printer comprising: a plurality of sheet feeders provided in a straight line or in matrix, which respectively have a hopper holding print sheets of a predetermined size, and which respectively feed the print sheets one by one; a printing mechanism which performs printing with respect to the print sheet fed from said sheet feeder; and a moving mechanism which moves said printing mechanism to a position corresponding to designated one of said sheet feeders.

In the printer, said plurality of sheet feeders are arrayed in a horizontal or vertical direction in a straight line, or in both directions in matrix, wherein said moving mechanism moves said printing mechanism in the horizontal or vertical direction, or in both directions.

Further, in the printer, the sizes of the print sheets held on at least two of the hoppers of said plurality of sheet feeders are different from each other.

Further, in the printer, said moving mechanism having: an endless belt which is connected to said printing mechanism and which moves in the horizontal or vertical direction parallel to an array direction of said plurality of sheet feeders; and a guide member for guiding movement of said printing mechanism.

In the printer of this embodiment, the sheet-conveyance path is not curved at a small radius of curvature, and even when used with inflexible print sheet, reliability can be maintained, thus printing can be made while selecting a print sheet from many types of print sheets. The plurality of sheet feeders, each having a hopper holding print sheets of a predetermined size, are arrayed in a straight line in a horizontal or vertical direction, or arranged into a matrix in the horizontal and vertical direction, and the printing mechanism is moved in the horizontal or vertical direction, or in the horizontal and vertical directions, along the direction of arrangement of the sheet feeders, which attains a relatively simple construction where the light printing mechanism is moved.

This obtains a printer which performs printing while selecting a desired sized sheet, reduces manufacturing cost, and further, improves maintainability.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken with the accompanying drawings in which: Fig. 1 is a schematic perspective view showing a first embodiment of the present invention; Fig. 2A is a plan view of the first embodiment in Fig. 1; Fig. 2B is a cross-sectional view cut along a line A A in Fig. 2A; Fig. 3 is a perspective view showing the arrangement of a sensor according to the present invention; Fig. 4 is a cross-sectional view of a paper-feeder according to the present invention; Fig. 5 is a block diagram showing the construction of the first embodiment according to the present invention; Fig. 6 is a perspective view showing the arrangement of a stacker according to the present invention; Fig. 7 is a flowchart showing an operation of moving a printing mechanism to a position opposite to a designated hopper; Fig. 8 is a perspective view showing a second embodiment of the present invention; and Fig. 9 is a perspective view showing a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail by way of example only in accordance with the accompanying drawings.

Fig. 1 is a schematic perspective view showing a first embodiment of the present invention. Fig. 2A is a plan view of the first embodiment in Fig. 1, and Fig. 2B is a cross-sectional view cut along a line A-A in Fig. 2A.

Note that in Figs. 1, 2A and 2B, a part of hoppers and paper feeders and a stacker are omitted for the sake of simple illustration. The omitted parts are shown in Figs.

3, 4 and 6 to be described later.

In Figs. 1, 2A and 2B, hoppers Sa to 5d are respectively placed on paper feeders 7a to 7d. The hopper Sa to 5d respectively hold print sheets 6 of a predetermined size. The print sheets 6 may have the same size or different sizes. In case of printing with respect to different sized print sheets, at least two hoppers hold the print sheets 6 of different sizes. The paper feeders 7a to 7d are arrayed, in parallel, in a straight line. The print sheets 6 in the hopper are fed one by one from a designated one of these paper feeders to a printing mechanism (printing unit) 1. The printing mechanism 1 lacks a pick roller to pick the print sheet 6 set in the hopper, a feed roller to feed convey the picked print sheet 6 to the printing unit in the printing mechanism 1 and motors to drive these rollers, a gear mechanism to decelerate the speed of the respective rollers to predetermined speeds and transmit the drive forces from the motors to the respective rollers, and a conveyance mechanism having a firm frame to hold these parts with high precision so as to maintain the conveyance of the print sheet with high precision.

The printing mechanism 1 is movable in the arrow B direction guided by two rails 2a and 2b parallel to the arrayed direction of the paper feeders 7a to 7d. The printing mechanism 1 performs printing with respect to the print sheet 6 fed from the paper feeders 7a to 7d. the printing mechanism 1 is connected to an endless belt 3 which is provided between the rails 2a and 2b and is parallel to the rails 2a and 2b. The belt 3 is set on two pulleys 4a and 4b. Accordingly, the printing mechanism 1 is moved via the belt 3 in the arrow B direction by rotating one of the pulleys 4a and 4b, to a position opposite to designated one of the paper feeders 7a to 7d.

the rails 2a and 2b, the belt 3, and the pulleys 4a and 4b constitute a moving mechanism. The pulleys 4a and 4b which move the belt 3 to move the printing mechanism 1 are connected to a forward/reverse rotatable pulley drive motor 15 (Fig 5). The moving mechanism changes the moving direction of the belt 3 and the printing mechanism 1 by the rotational direction of the pulley drive motor 15.

Further, the respective paper feeders 7a to 7d have sensors 8a to 8d respectively for detecting that the printing mechanism 1 is positioned at an opposite position.

As shown in Fig. 3, the sensor 8d is provided at the lower portion of the hopper 5d on the printing mechanism 1 side.

The sensors 8a to 8d are, for example, photo sensors having a light-emitting portion and a photo reception portion. It may be arranged such that when the printing mechanism 1 moves to a position opposite to the paper feeder 7d, for example, a projection la provided at the printing mechanism 1 blocks light incident upon the photo reception portion from the light-emitting portion.

Further, the paper feeders 7a to 7d respectively have pick rollers 9a to 9d for picking a print sheet to be supplied to the printing mechanism 1, separation plates 10a to 10d for conveying the print sheet one by one, and feed rollers lla to lld for feeding the picked print sheet to the printing mechanism 1. As shown in Fig. 4, the pick roller 9c is provided at the bottom of the hopper Sc. The print sheet 6 picked by the pick roller 9c is passed through an opening at the bottom of the hopper 5c, and horizontally conveyed while it is almost not bent, and the feed roller 11c horizontally feeds the print sheet 6 substantially without bending it. The height of the print sheet 6 fed by the feed roller 11c is approximately the same as that of a paper insertion hole 1b of the printing mechanism 1.

The pick rollers 9a to 9d and the feed rollers lla to lld are respectively connected to pick motors 12a to 12d and feed-roller drive motors 13a to 13d.

Further, as shown in Fig. 5, the printing mechanism 1, sensors 8a to 8d, the pulley drive motor 15, the pick motors 12a to 12d and the feed-roller drive motors 13a to 13d are connected to a controller 14.

The controller 14 outputs print information from an external apparatus to the printing mechanism 1. Further, the controller 14 detects a paper feeder which is opposite to the printing mechanism 1 based on signals from the sensors 8a to 8d. The controller 14 controls the rotational direction and rotating/stoppage of the pulley drive motor 15, and moves the printing mechanism 1 by the moving mechanism including the pulley drive motor 15. With respect to one selected paper feeder, the controller 14 drives the pick roller and the feed roller at a predetermined timing, thus feeds the print sheets set on the paper feeder one by one. The controller 14 has a memory 16 in which the sizes of the print sheets 6 set in the paper feeders 7a to 7d are stored in advance. For example, identification numbers are assigned to the respective paper feeders in correspondence with the order of the paper feeder. In Fig. 1, an identification number "1" is assigned to the leftmost paper feeder 7a, and the identification number increases from the next paper feeder to the rightmost paper feeder, i.e., identifications "2", "3" and "4" are assigned to the paper feeders 7b to 7d.

The sizes of the print sheets to be set on the hoppers of the corresponding paper feeders are set in accordance with these identification numbers.

Further, as shown in Fig. 6, a stacker 17 having a width corresponding to the array of the paper feeders 7a to 7d is provided on the opposite side to the paper feeders 7a to 7d, with a moving area of the printing-mechanism 1 between the stacker and the paper feeders. The print sheet 6 printed and discharged by the printing mechanism 1 is stacked naturally falling on the stacker 17.

Next, the operation of the printer having the above construction will be described.

When the printer does not perform printing operation, i.e., it is in stand-by status, the printing mechanism 1 is at a position (home position) opposite to a particular one of the paper feeders 7a to 7d. In this state, when a print-start instruction has been received from the external apparatus, if the size of print sheet designated in the print-start instruction is different from that of the print sheet set in the hopper of the paper feeder at the home position, the moving mechanism is operated to move the printing mechanism 1 to a position opposite to a paper feeder having a hopper holding the print sheet of the designated size.

The operation of moving the printing mechanism 1 to the position opposite to the designated paper feeder will be described with reference to Fig. 7.

First, the controller 14 specifies a paper feeder PF1 having a hopper holding the print sheet of the designated size from the information on the print sheet sizes prestored in the memory 16, and obtains an identification number ID1 corresponding to the paper feeder (step Al).

This is made by, e.g., checking the print sheet sizes from the hopper with the identification number 1 to the hopper with the identification number 4, thus determining the identification number corresponding to a print sheet size which is the same as the designated size.

Then the hopper identifies a paper feeder PF2 currently opposite to the printing mechanism 1, and obtains an identification number ID2 corresponding to the paper feeder PF2 (step A2). Next, the identification numbers ID1 and ID2 are compared with each other, to determine the rotational direction of the pulley drive motor 15 of the moving mechanism (step A3). That is, if ID1 > ID2 holds, the printing mechanism 1 is moved to the right (step A4), otherwise, moved to the left (step A5). At this time, the controller 14 rotates the pulley drive motor 15 so as to move the printing mechanism 1. Then, it is determined whether or not the printing mechanism 1 has been detected by a sensor S1 corresponding to the designated paper feeder PF1 (step A6 or A7). If the printing mechanism 1 has not been detected, the process returns to step A4 or A5, while if the printing mechanism 1 has been detected, the rotation of the pulley drive motor 15 is stopped (step A8).

In a case where the print-sheet size designated in the print-start instruction is the same as that of the print sheet set in the hopper of the paper feeder at the home position, the pulley drive motor 15 is not operated.

When the moving operation of the printing mechanism 1 has been completed, the pick motor and the feed-roller drive motor of the paper feeder opposite to the printing mechanism 1 are operated, to feed the print sheets 6 set in the hopper one by one to the printing mechanism 1. As the height of paper discharge holes of the paper feeders 7a to 7d and that of the paper insertion hole lb of the printing mechanism 1 are approximately the same, the print sheet fed from the paper feeders 7a to 7d is inserted into the printing mechanism 1, and then printing is performed. In the printing mechanism 1, when the printing with respect to one print sheet 6 has been completed, the print sheet 6 is discharged from the printing mechanism 1 and stacked on the stacker 17. If printing is to be performed by using the print sheet 6 of the same size, the print sheet 6 is fed from the paper feeders 7a to 7d to the printing mechanism, and the printing mechanism performs printing. If the printing is to be performed by using the print sheet of a size different from the previous sheet size, when the printing mechanism 1 has discharged the previous print sheet 6, the pulley drive motor 15 is operated to move the printing mechanism 1 to a position opposite to a paper feeder having a hopper holding the print sheet 6 of the desired size, then, the print sheet 6 is fed to the printing mechanism 1 and the next printing is performed.

Accordingly, the discharged print sheet 6 is stacked on the stacker 17 at a position corresponding to the paper feeder that fed the print sheet 6 to the printing mechanism.

Thus, the print sheets 6 are stacked on the stacker 17 at positions corresponding to the paper feeders.

When a series of printing operation has been completed, the printing mechanism 1 is returned to the home position, and the printer becomes in the stand-by status.

Fig. 8 is a perspective view showing the second embodiment of the present invention.

The basic structure and principle of the second embodiment are the same as those of the first embodiment in Fig. 1, however, in the second embodiment, the hoppers and the paper feeders are arrayed in a vertical direction.

That is, hoppers 25a to 25c and paper feeders 27a to 27c are arrayed in the vertical direction, and a belt 23 of the moving mechanism, shafts 22a and 22b for guiding the movement of a printing mechanism 21 are provided parallel to the paper feeders 27a to 27c in the vertical direction.

Further, a plurality of stackers are provided in the up-and-down direction at positions where the print sheets 6 fed from the paper feeders 27a to 27c to the printing mechanism 21 are discharged and stacked in correspondence with the paper feeders.

Regarding the identification numbers, for example, an identification number "1" is assigned to the lowest paper feeder 27c, then, the identification numbers having greater values "2" and "3" are assigned to the upper paper feeders 27b and 27a respectively.

The operation of the second embodiment is the same as that of the first embodiment except that the printing mechanism is moved not in the horizontal direction but in the vertical direction.

Fig. 9 is a perspective view showing the third embodiment of the present invention.

The basic structure and principle of the third embodiment are the same as those of the first embodiment in Figs. 1 and 2, however, in the third embodiment, the hoppers and the paper feeders are arranged in the horizontal and vertical directions in matrix.

That is, hoppers 35a to 35h and paper feeders 37a to 37h are provided in the horizontal and vertical directions in matrix, and belts 33a and 33b of the moving mechanism are provided in the horizontal and vertical directions parallel to the paper feeders 37a to 37h. Further, rails 32a and 32b for guiding horizontal movement of a printing mechanism 31 and shafts 32c and 32d for guiding vertical movement of the printing mechanism 31 are provided in the horizontal and vertical directions parallel to the belts 33a and 33b. Further, a plurality of stackers having a width corresponding to that of the arrays of the paper feeders are arrayed in the up-and-down direction. The print sheets on which printing have been performed by the printing mechanism 1 are stacked on the stackers at positions corresponding to the respective paper feeders 37a to 37h.

Regarding the identification numbers, for example, a two-digit number is used; in the identification number, the lower-digit value becomes greater toward the rightmost paper feeder, while the upper-digit value becomes greater in accordance with upper arrays of paper feeders. That is, in this embodiment, identification number "01" is assigned to the lower-left hopper 35e, then, identification numbers "02", 03" .... are assigned to the righthand paper feeders, while identification numbers "11", "12" .... are assigned to the upper arrays of paper feeders.

The operation of the third embodiment is the same as that of the first embodiment except that the printing mechanism 31 is moved in the horizontal or vertical direction or in both directions.

To move the printing mechanism 31 to a position opposite to the designated paper feeder PF1, the position of the hopper of the paper feeder is determined. That is, it is determined as to on what side the hopper is positioned with respect to the paper feeder PF2 currently opposite to the printing mechanism 31. For example, if the upper digit value of the identification number ID2 of the paper feeder PF2 is greater than that of the identification number ID1 of the paper feeder PF1, it is determined to move the printing mechanism 31 downward, while if the upper digit value of the identification number ID2 is smaller than that of the identification number ID1, it is determined to move the printing mechanism 31 upward.

Then, a pulley drive motor 35b which moves the belt 33b is operated to move the printing mechanism 31 while monitoring the output from a sensor S3 corresponding to a paper feeder PF3 having an identification number ID3 where the upper digit value is the same as that of the identification number ID1, and the lower digit value is the same as that of the identification number ID2, i.e., the paper feeder PF3 is at the same position as that of a sensor S1 of the designated hopper in the vertical direction, and at the same position as that of a sensor S2 corresponding to the paper feeder PF2 currently opposite to the printing mechanism 31 in the horizontal direction.

When the sensor S3 has detected the printing mechanism 31, the rotation of the pulley drive motor 35b moving the belt 33b is stopped.

Next, if the lower digit value of the identification number of the paper feeder PF2 is greater than that of the identification number of the paper feeder PF1, it is determined to move the printing mechanism 31 leftward, while if the lower digit value of the identification number of the paper feeder PF2 is smaller than that of the identification number of the paper feeder PF1, it is determined to move the printing mechanism 31 rightward.

Then, the pulley drive motor 35a which drives the belt 33a is rotated in the direction as determined as above while monitoring the output from the sensor S1 corresponding to the designated hopper. When the sensor S1 has detected the printing mechanism 31, the rotation of the pulley drive motor 35a is stopped.

The present invention has been described based on the several embodiments as above, however, it is apparent that the present invention is not limited to these embodiments.

For example, the mechanism to drive the printing mechanism by moving the belt by pulleys may be replaced with another mechanism as long as it moves the printing mechanism in parallel. Further, it may be arranged such that the sensor which detects the hopper opposite to the printing mechanism comprises a line sensor such as a CCD, and is provided at the printing mechanism, and the hoppers have identification numbers. In this case, when the printing mechanism moves in front of one hopper, the sensor reads the identification number of the hopper, and identifies the hopper opposite to the printing mechanism and the position of the printing mechanism. Further, the pick roller may be provided on the upper surface side of the hopper. Further, the sheet discharge direction of the printing mechanism and the position of the stacker are not necessarily opposite to the sheet insertion direction from the hopper, but may be provided in an arbitrary direction in which the printing mechanism can discharge the print sheet without bending it.

For example, if it is arranged such that the printing mechanism feeds back the print sheet upward or downward toward the stacker, the setting area of the printer can be reduced.

As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.

Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently of other disclosed and/or illustrated features.

The text of the abstract filed herewith is repeated here as part of the specification.

A printer comprises a plurality of paper feeders provided in a straight line or in matrix which respectively have a hopper holding print sheets of a predetermined size and which respectively feed the print sheets one by one, a printing mechanism which performs printing with respect to the print sheet fed from the paper feeder, and a moving mechanism which moves the printing mechanism to a position opposite to designated one of the paper feeders. The paper feeders are arrayed in a horizontal or vertical direction or in both horizontal and vertical directions in matrix, and the moving mechanism moves the printing mechanism in the horizontal or vertical direction or both horizontal and vertical directions. Further, the sizes of the print sheets held on at least two hoppers of the paper feeders are different from each other.

The moving mechanism has an endless belt which is connected to the printing mechanism and which moves in the horizontal or vertical direction parallel to the array direction of the paper feeders, and a guide member which guides the movement of the printing mechanism.

Claims (14)

1. A method of printing on sheet material comprising providing a plurality of spatially-distributed sources of different sheet materials, and moving a printing mechanism into operating relationship with a selected one of said sources depending upon which sheet material is to be printed.

2. Printing apparatus comprising a plurality of spatially-distributed storage means for different sheet materials, a printing mechanism for receiving sheet material from said storage means and for printing on said sheet material, and means for moving the print mechanism into operative relationship with a selected one of said storage means depending on which sheet material is to be printed.

3. - A sliding printer comprising: a plurality ofsheet feeders provided in a straight line or in matrix, which respectively have a hopper holding print sheets of a predetermined size, and which respectively feed the print sheets one by one; a printing mechanism which performs printing with respect to the print sheet fed from said sheet feeder; and a moving mechanism which moves said printing mechanism to a position corresponding to designated one of said paper feeders.

4 The sliding printer according to claim 3, wherein said plurality of sheet feeders are arrayed in a straight line in a horizontal direction.

5- The sliding printer according to claim 3, wherein said plurality of sheet feeders are arrayed in a straight line in a vertical direction.

6. The sliding printer according to claim 3, wherein said plurality of set feeders are provided in horizontal and vertical directions in matrix, and wherein said moving mechanism moves said printing mechanism in the horizontal and vertical directions.

7. The sliding printer according to claim 3, wherein the sizes of the print sheets held on at least two of the hoppers of said plurality of sheet feeders are different from each other.

; The sliding printer according to claim 3, wherein said moving mechanism having: an endless belt which is connected to said printing mechanism and which moves in the horizontal or vertical direction parallel to an array direction of said plurality of paper feeders; and a guide member for guiding movement of said printing mechanism.

The sliding printer according to claim3, wherein when said moving mechanism has moved said printing mechanism to the position corresponding to the designated one of said plurality of sheet feeders, the height of a sheet discharge hole of said designated sheet feeder is the same as that of a sheet insertion hole of said printing mechanism, and wherein said sheet feeder feeds the print sheet without bending it to said printing mechanism.

10. The sliding printer according to claim 3, wherein when said printer is in stand-by status, said printing mechanism is at a position opposite to any one of said plurality of sheet feeders.

The sliding printer according to claim 3, when printing with respect to the print sheet of a first size has been completed, if printing is performed with respect to the print sheet of a second size, said moving mechanism moves said printing mechanism, when said printing mechanism has discharged the print sheet of the first size, to a position opposite to another one of said plurality of sheet feeders having the hopper holding the print sheet of the second size, and then the print sheet of the second size is fed to said printing mechanism.

12. The sliding printer according to claim 3, further comprising a stacker having a width corresponding to a width of an array of said plurality of sheet feeders, at a position opposite to said plurality of sheet feeders, with an area, in which said printing mechanism moves, between said stacker and said plurality of sheet feeders.

13. The sliding printer according to claim 3, further comprising: a memory in which sizes of the print sheets respectively held in said plurality of sheet feeders and arrangement of said plurality of sheet feeders are stored; and a plurality of sensors which are respectively provided at said plurality of sheet feeders and which respectively detect that said printing mechanism is at a position opposite to said sheet feeder, wherein a first sheet feeder, holding the print sheet of a size designated from an external apparatus, is specified by referring to contents of said memory, and positional relation between said first sheet feeder and a second sheet feeder currently opposite to said printing mechanism is determined, and wherein a direction in which said moving mechanism is operated to move said printing mechanism is determined, and said moving mechanism is operated while monitoring an output from one of said plurality of sensors which corresponds to said first sheet feeder or one of said plurality of sensors which is at the same position as that of said first sheet feeder in the vertical direction, further wherein said moving mechanism is stopped when said sensor has detected said printing mechanism.

14. A method of or apparatus for printing substantially as herein described with reference to any of the accompanying drawings.