GB2150921A - Automatic shoot feeding device, particularly for copiers and other machines having sheet transport mechanisms and assemblies therewith - Google Patents

Abstract

An automatic sheet feeding device 10 comprising a frame 36 cooperates with a copying apparatus 12 or the like for advancing a single sheet to be copied from a stack of sheets 85 on an inclined tray 42. A sheet drive mechanism 46 of the sheet feeding device feeds the sheets into an entrance end of a feeding device of the copying apparatus 12. A cover 44 is pivotally mounted on the sheet feeding device 10 and cooperates with a roller-separating device to facilitate the clearing of sheet jams. A clutch mounted on shaft 52 of the lower roller 56 of a pair 56, 57 engages a gear on the shaft 52 when two or more sheets enter the nip 56, 57 to return the lower sheet(s) to the stack 85, see Fig 3 (not shown). The motor for driving the shafts 52, 53 is electrically interconnected with the copier 12. <IMAGE>

Description

SPECIFICATION Automatic sheet feeding device, particularly for copiers and other machines having sheet transport mechanisms and assemblies therewith The present invention relates generally to an automatic sheet feeding device, and more particularly, to an automatic sheet feeding device for feeding sheets into copiers and other machines.

Many business machines including copying apparatus have sheet feeding or transport mechanisms and assemblies therewith which operate semi-automatically, and the operator must manually insert each sheet being processed into an entrance end of the transport mechanism to be engaged and transported by the sheet transport mechanism through the work station. Since this manual feeding procedure is extremely time consuming and causes considerable delay, it would be desirable to have the sheets automatically inserted into the entrance end of the transport mechanism.

The term "sheet" as contemplated by the present invention is used to describe a single unprinted sheet, an original document, or a folded sheet such as an envelope. "Sheet material" as used herein refers to paper, synthetic resin, metal foil and laminates.

It is believed possible by means of the invention to provide a novel automatic document feeding device for sequentially advancing each sheet of a stack of sheet material therein into engagement with a sheet feeding or transport mechanism of a business machine and thereby increase the efficiency of the machine and its operator.

It is also believed possible by means of the invention to provide such a device which will be powered and controlled by the associated machine so as to operate synchronously therewith.

A further believed possibility of the invention is to provide such a device which pe mits easy clearance of sheet jams and avoids damage to the sheets being processed.

A further believed possibility of the invention is to provide such an automatic sheet feeding device which may be readily fabricated and will enjoy long life in operation.

According to a first aspect of the invention there is provided an automatic sheet feeding device comprising: A. a frame including a pair of upstanding side plates; B. an inclined tray supported in said frame adapted to hold a stack of sheets; and C. sheet drive means supported on said frame for advancing a single sheet from a stack of sheets located on said tray, said sheet drive means including:: i. a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said tray adapted to receive sheets of sheet material supported on said tray, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon; ii. gear drive means mounted on said frame outwardly of one of said side plates and including gears on said shafts of said upper and lower roller means, said gear on said upper drive shaft being engaged therewith and said gear on said lower drive shaft being normally disengaged therefrom; and iii. clutch means mounted on said shaft of said lower roller means and operatively connected to said gear thereon, whereby said clutch means will drivingly engage said lower roller shaft with its gear and thereby said gear drive means when two or more sheets are fed simultaneously from said tray into said nip defined by said upper and lower roller means; D. motor means on said frame for rotatably driving said gear drive means; E. circuit means for said motor means adapted to be electrically connected to the associated sheet processing apparatus for controlling supply of power to said motor means for actuating said sheet drive means in response to operation of the feeding mechanism of the associated sheet processing apparatus;; F. a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing of sheet jams; and G. roller separating means on said frame cooperating with said cover and said roller shafts to separate said set of roller means when said cover is pivoted from its closed position to its open position.

According to a second aspect of the invention there is provided a sheet processing apparatus in combination with an automatic sheet feeding device; comprising: A. a sheet processing apparatus having a processing station, a feeding mechanism for feeding sheets from an entrance position through said processing station, and an electrical circuit including control means; and B. an automatic sheet feeding device including: i. a frame including a pair of upstanding side plates mounted on said processing apparatus; ii. an inclined sheet tray supported in aid frame and adapted to hold a stack of sheets therein; iii. sheet drive means supported on said frame for advancing a single sheet from a stack of sheets located on said sheet tray to said entrance position of said feeding mechanism, said sheet drive means including a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said sheet tray adapted to receive sheets of paper, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon, gear drive means mounted on said frame outwardly of one of said side plates and including gears on said shafts of said upper and lower roller means, said gear on said upper drive shaft being engaged therewith and said gear on said lower drive shaft being normally disengaged therefrom, and clutch means mounted on said shaft of said lower roller means and opera tively connected to said gear thereon, whereby said clutch means will drivingly engage said lower roller shaft with its gear and thereby said gear drive means when two or more sheets are fed simultaneously from said tray into said nip defined by said upper and lower roller means; iv. motor means on said frame for rotatably driving said gear drive means;; v. circuit means for said motor means electrically connected to said electrical circuit of said sheet processing apparatus for controlling supply of power to said motor means for actuating said sheet drive means in response to operation of the feeding mechanism of said sheet processing apparatus by said control means thereof; vi. a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing sheet jams; and vii. roller separating means on said frame cooperating with said cover and said roller shafts to separate said set of roller means when said cover is pivoted from its closed position to its open position.

According to a third aspect of the invention there is provided a copying apparatus in combination with an automatic document feeding device; comprising: A. a copying apparatus having a copying station, feeding mechanism for feeding documents from an entrance position through said copying station, and an electrical circuit including control means; and B. an automatic document feeding device including: i. a frame including a pair of upstanding side plates mounted on said copying apparatus; ii. an inclined document tray supported in said frame and adapted to hold a stack of documents; iii. document drive means supported on said frame for advancing a single document from a stack of documents located on document tray to said entrance position of said feeding mechanism, said document drive means including a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said document tray adapted to receive documents supported on said tray, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon, gear drive means mounted on said frame outwardly of one of said side plates and including gears on said shafts of said upper and lower roller means, said gear on said upper drive shaft being engaged therewith and said gear on said lower drive shaft being normally disengaged therefrom, and clutch means mounted on said shaft of said lower roller means and operatively connected to said gear thereon, whereby said clutch means will drivingly engage said lower roller shaft with its gear and thereby said gear drive means when two or more documents are fed simultaneously from said tray into said nip defined by said upper and lower roller means; iv. motor means on said frame for rotatably driving said gear drive means;; v. circuit means for said motor means electrically connected to said electrical circuit of said copying apparatus for controlling supply of power to said motor means for actuating said document drive means in response to operation of the feeding mechanism of said copying apparatus by said control means thereof; vi. a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing of document jams; and vii. roller separating means on said frame cooperating with said cover and said roller shafts to separate said set of roller means when said cover is pivoted from its closed position to its open position.

According to a fourth aspect of the invention there is provided a sheet processing apparatus in combination with an automatic sheet feeding device; comprising: A. a sheet processing apparatus including: i. a processing station; ii. a feeding mechanism having roller means, having an entrance gate, and a main sheet moving belt drive means for moving a sheet of material from an entrance position at said entrance gate through said processing station; iii. an electrical circuit including control means having a sheet sensing means detect a sheet at said entrance position; B. an automatic sheet feeding device comprising:: i, a frame including a pair of upstanding side plates mounted on said processing apparatus; ii. a sheet tray supported in said frame and adapted to hold a stack of sheets therein; iii. sheet drive means supported on said frame for advancing a single sheet from a stack of sheets located on said sheet tray to said entrance position of said feeding mechanism, said sheet drive means including a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said sheet tray adapted to receive sheets of paper, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon, roller drive means mounted on said frame for driving said roller means, and clutch means operatively connected between said lower roller means and said roller drive means, whereby said clutch means will drivingly engage said lower roller shaft when two or more sheets are fed simultaneously from said tray into said nip defined by said upper and lower roller means; iv. motor means on said frame for driving said roller drive means; v. circuit means for said motor means electrically connected to said electrical circuit of said sheet processing apparatus for controlling supply of power to said motor means for actuating said sheet drive means in response to operation of the feeding mechanism of said sheet processing apparatus by said control means thereof.

A preferred embodiment of the invention is a sheet feeding device used in combination with a sheet processing apparatus. The sheet processing apparatus has a sheet processing station, a semiautomatic feeding mechanism for feeding sheets from an entrance position through the processing station, and an electrical circuit including control means. The automatic sheet feeding device includes a frame mounted on the sheet feeding apparatus including a pair of upstanding side plates, an inclined sheet tray supported in the frame and adapted to hold a stack of sheets, and sheet drive means.The sheet drive means is supported on the frame for advancing a single sheet from a stack of sheets located on the sheet tray to the entrance position of the semi-automatic feeding mechanism, the sheet drive means includes a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of the sheet tray adapted to receive sheets supported on the tray, the upper and lower roller means each including a shaft extending through and journalled for rotation in the side plates of the frame and at least one roller mounted thereon, gear drive means mounted on the frame outwardly of the side plates and includ ing gears on the shafts of the upper and lower roller means, the gear on the upper drive shaft being engaged therewith and the gear on the lower drive shaft being normally disengaged therefrom, and clutch means mounted on an end of the shaft of the lower roller means and operatively connected to the gear thereon, whereby the clutch will drivingly engage the roller shaft with its gear and thereby the gear drive means when two or more sheets are fed simultaneously from the tray into the nip defined by the upper and lower roller means.The automatic sheet feeding device further including motor means on the frame for rotatably driving the gear drive means, circuit means for the motor means electrically connected to the electrical circuit of the sheet processing apparatus for controlling supply of power to the motor means for actuating the sheet drive means in response to the operation of the semi-automatic feeding mecha nism of the sheet processing apparatus by the control means thereof, a cover journalled in the frame for pivotal movement between a closed and an open position to permit clearing of sheet jams, and roller separating means on the frame cooperating with the cover and the roller shafts to separate the set of roller means when the cover is pivoted from its closed position to its open position.

In the preferred embodiment, the sheet drive means includes a second set of upper and lower roller means defining and nip spaced from the first set of roller means, the upper and lower roller means of the second set each including a shaft extending through and journalled for rotation in the side plates and having at least one roller thereon.

The second set of upper and lower roller means and the entrance position are spaced apart a distance less than the length between the trailing and leading edges of the sheets to be fed.

The invention will be described by way of exam ple with reference to the accompanying drawings, wherein: Figure 1 is a fragmentary perspective view of a copying apparatus with an automatic document feeding device embodying the present invention mounted thereon; Figure 2 is a partially diagrammatic side elevational view of the tray and rollers of the feeding device with a pair of sheets in the nip of the feed rollers; Figure 3 is a similar view showing the manner in which the feed rollers of the automatic document feeding device returns the lower sheet to the stack of docuuments; Figure 4 is a fragmentary top elevational view of the document feeding device with portions removed or in section for clarity of illustration; Figure 5 is a fragmentary perspective view of the feed rollers and document guide of the document feeding device showing their relative positions;; Figures 6 and 7 are partially diagrammatic illustrations showing the manner of removal of a feed roller from the document feeding device; Figure 8 is a side elevational view of the gear drive train and motor drive of the document feeding device with portions broken away for clarity of illustration; Figure 9 is a fragmentary end elevational view of the document drive mechanism of the document feeding device with portions in section for purposes of illustration; Figure 10 is a fragmentary end elevational view of the one way spring clutch of the document feeding device; Figures 11 and 12 are fragmentary side elevational views of the document feeding device with portions broken away and omitted for clarity of illustration, showing a pair of the feed rollers (in phantom line) and the cover in their closed and open positions, respectively;; Figures 13-16 are schematic diagrams showing the normal operation of the copying apparatus and document feeding device as a sheet is fed from the stack therethrough; Figure 17 is a schematic wiring diagram of the document feeding device embodying the present invention; and Figure 18 is a fragmentary side elevational view of the copying apparatus with the cover and housing broken away for clarity of illustration.

Referring first to Figure 1, therein is illustrated an automatic document or sheet feeding device embodying the present invention and generally designated by the numeral 10 as mounted on a conventional copying apparatus generally designated by the numeral 12. The copying apparatus 12 has a main housing 14 with a pivotally mounted cover 16 thereon, and contains a copying station (not shown) under the cover 16 and a control circuit 18 to reproduce documents on copier sheet material 20 taken from copier paper tray 22 as the documents are fed through the copying apparatus 12 in a face down orientation.

As seen in Figure 18, the cover 16 contains a semi-automatic feeding or transport mechanism generally designated by the numeral 24 and including a shaft 26 having a plurality of pinch roll ers 28 thereon, document photosensor 30, entrance gate 32 and main document belt drive 34.

The shaft 26 and the plurality of pinch rollers 28 thereon are journalled in the cover 16 and rotatably driven by a drive belt 33 concurrently with main document belt drive 34 as controlled by the copier control circuit 18, and they are mounted for reciprocal vertical movement within the cover 16 for purposes to be explained hereinafter. The document photosensor 30 is located in the travel path after the pinch rollers 28 and detects the presence of a document in position to be fed through the work station by the semi-automatic document feeding mechanism 24. The entrance gate 32 is mounted for vertical movement and is mechanically coupled to the shaft 26 as indicated by phantom line 35. Thus, the entrance gate 32 and the shaft 26 with its pinch rollers 28 will reciprocate in the cover 16 as will be explained more fully hereinafter.The main document belt drive 34 advances the document through the copying station to an exit end of the copying apparatus.

The automatic document feeding device 10 for advancing a single document from a stack of documents to the entrance gate 32 of the copying apparatus 12 has a frame 36 mounted on one end of the copying apparatus 12 above the copier paper tray 22. The frame 36 includes a pair of upstanding side plates 38, 39 and covers 40 removably mounted on the outer side thereof. The frame 36 supports an inclined document tray 42 which holds a stack of documents 85 to be copied, and an inclined document guide 43 to direct the documents being fed from the document feeding device 10 into the entrance end of the copying apparatus 12.

A cover 44 is journal led in the frame 36 for pivotal movement between a closed position and an open position for clearing document jams, as seen in Figures 11 and 12. As seen in Figure 4, extending below the cover 44 is a document drive mechanism for separating and feeding a single document and generally designated by the numeral 46. The drive mechanism includes a gear drive train generally designated by the numeral 48 located outwardly adjacent the side plate 38 and a roller separation mechanism generally designated by the numeral 50 located outwardly adjacent side plate 39.

As best seen in Figures 4 and 5, a multiplicity of parallel, spaced apart shafts 52, 53, 54 and 55, extend through and are journalled for rotation in the side plates 38, 39. Each of the shafts 52, 53, 54 and 55 has a high friction surface rubber roller 56, 57, 58 and 59 mounted thereon for rotation therewith.

It should be noted that portions of the periphery of the lower rollers 56 and 58 are disposed within notches formed in the lower edge portions of inclined document tray 42 and guide 43. Rollers 56 and 57 cooperate to form a nip therebetween which is disposed upwardly of the lower edge of the document tray 42 while rollers 58 and 59 cooperate to form a nip therebetween which is in the feed path therefrom. The distance between rollers 58, 59 and entrance gate 32 is generally seven and one half inches which is less than the length between the leading and trailing edges of the documents to be fed for purposes to be explained hereinafter.

Referring now to Figures 4 and 8-10, a motor drive 60 for rotating the gear drive train 48 of the document drive mechanism 46 is mounted beneath document guide 43 on side plate 38. The motor 60 has a shaft 62 which rotates gear 64 which drives the intermeshed gears 66 to rotate the shafts 54, 55 and the rollers 58, 59 thereon. The transfer pinion gear 68 on the lower gear 66 drives idler gear 70 and idler gear 72, which has a transfer pinion gear 73 thereon which in turn drives gear 74 which is rotatably mounted on shaft 52 between a bushing 76 and a slip or friction clutch generally designated by the numeral 78. The transfer pinion gear 75 on the gear 74 drives the idler gear 80 which in turn rotates the gear 82 rotatably mounted on the shaft 53.A one way spring clutch 84 operatively connects the shaft 53 and gear 84 for concurrent rotation but permits freewheeling of the shaft 53 if shaft 53 is driven faster than gear 82. All idler gears in the gear drive train 48 are mounted on stub shafts supported on the side plate 38.

The friction clutch 78 has a pair of bushings 126 and 128 axially solidable on but splined for rotation with the end of shaft 52. A coil spring 130 biases the bushings 126, 128 apart, and the amount of compression of the spring 130 and thus the force exerted by the bushing 126 on the gear 74 can be adjusted by axial movement of the screw 132 which is threadably engaged in the end of the shaft 52. By loosening the screw 132, the outer bushing 128 can move axially outwardly and reduce the compression of the spring. The thrust washer 134 is disposed between the head of the screw and bushing 128.

Turning now to Figures 6 and 7, therein illustrated is the mounting of the shaft 55 and roller 59 which is illustrative of that also used for the several shafts 52, 53 and 54 and rollers 56, 57 and 48.

The shaft 55 is journalled in the side plates 38, 39 by bushings 76 and space 86 and has C-clips 88 releasably retained thereon to limit axial movement thereof towards the side plate 38. The roller 59 and the gear 66 have set screws 90 releasably retaining them on shaft 55 against relative axial and rotational movement. To remove the shaft 55 and the associated parts, set screws 90 are disengaged and the C-clips 88 are removed to allow shaft 55 to be slid through side plate 38 to be removed therethrough, enabling removal and replacement of roller 59.

As best seen in Figures 4, 11 and 12, the cover 44 has a pair of pivot shafts 92 (only one shown) mounted thereto and having a reduced end portion journalled in side frames 38, 39 to allow pivotal movement of the cover 44 between a closed position and an open position for clearing document jams in the feed rollers. As the cover 44 pivots to the open position, the roller separation mechanism 50 moves the roller shafts 53 and 55 to separate the pairs of cooperating rollers 46, 57, 58 and 59.

The roller separation mechanism 50 includes a slide plate 94 having a pair of inclined cam slots 96 therein and a pair of studs 98, 100 extending inwardly through the elongated slots 102 in the side plate 39. The shafts 53 and 55 extend through the elongated apertures 104 in the side plate 39 and are disposed in the inclined slots 96 of the plate 94. The ends of the leaf springs 106 bear on the ends of the cooperating pair of shafts 52, 53 and 54 and 55 normally biasing shafts 53, 55 towards the shafts 52, 54, thereby biasing rollers 56, 57 and 58, 59 into surface contact with one another.

When the cover 44 is pivoted from its closed position (Figure 11) to its open position (Figure 12) it bears against stud 98 to slide the plate 94. As the plate 94 moves to the right as seen in Figure 12, the shafts 53, 55 which are disposed in the inclined slots 96 are moved upwardly in the slots 96 to separate the rollers 57, 59 from the rollers 56, 58. The side plate 38 is provided with a sufficient amount of clearance to allow the shafts 52 and 55 to pivot thereabout as one end of each shaft is moved upwardly by slide plate 94. The gear drive mechanism 48 is also provided with sufficient clearance or play to allow such movement. A cam projection or tab 108 on the slide plate 94 is operatively engageable with the microswitch 110 for disconnecting the supply of power to the motor 60 when the cover 44 is moved to its open position.

As illustrated in Figure 17, a control circuit generally designated by numeral 112 of the document feeding device 10 controls the supply of power from the control circuit 18 of copying apparatus 12 to the drive motor 60. The manually actuated switch 114 activates light 116 and motor 60 of the automatic document feeding device 10 through the circuit board 118. The cam-operated mircoswitch 110 deactivates the motor 60 in response to movement of the cover 44 to its open position.

To initiate a copying operation or sequence, the operator simply places the stack of documents 85 in a face down orientation of the document tray 42.

Then the operator presses the switch 114 to activate the motor drive 60 to rotate gear drive train 48 illustrated in Figure 8. It should be noted that the automatic document feeding device 10 can feed a stack of documents 85 having a height which is smaller than or equal to the distance between the upper nip forming portion of lower roller 56 and the plane defined by the top surface of the tray 42, ie a stack of approximately thirty documents.

As seen, Figures 2 and 3 illustrate the operation of the document drive mechanism 46 of the document feeding device 10 to feed only a single document from a stack of documents 85 located on document tray 42. It must be understood that the coefficient of friction between rubber and rubber, or between rubber and paper, is much greater than that of paper and paper. The clutch 78 is adjusted to slip should two or more sheets enter into the nip defined by the rollers 56, 57.

When the motor drive 60 is activated, the gear drive train 48 drives rollers 58 and 59 at a surface speed three times faster than that of the roller 57.

The roller 56 is driven by driving contact with the rotating roller 57, ie the rubber to rubber friction contact, as the friction clutch 78 will slip relative to the gear 74. Normally, a single sheet on the top of stack 85 will be gravity fed into contact with the rotating lower roller 56 and swept thereby into the nip defined by rollers 56, 57 and the sheet driven by upper roller 57 will exert a sufficient force on lower roller 56 to rotate the same through the rubber to paper friction contact, as the friction clutch will again slip relative to the gear 74. However, if two sheets are fed simultaneously between rollers 56 and 57 (Figure 2), the paper to paper friction contact between the two sheets is too small to overcome the frictional force between the friction clutch 78 and the gear 74.Thus, it will be understood that friction clutch 78 engages the shaft 52 with the gear 75 to reverse the rotation of the roller 56 as seen in Figure 3 to drive the bottom sheet backwardly along the feed path onto the stack of documents 85. As the bottom sheet leaves the nip between rollers 56, 57, roller 56 engages the single (formerly upper) sheet remaining in the nip. Thereafter, the clutch 78 disengages and roller 56 reverses its direction and cooperates with the roller 57 to feed the sheet to the nip between the second pair of feed rollers 58, 59.

As best seen in Figures 13-16, a single document 115 is moved from the stack of documents 85 by the rollers 56, 57. Thereinafter, the document is captured in the nip defined by rollers 58, 59 which have a surface speed three times faster than that of the rollers 56, 57. Hence, the drag of the document through the rollers 56, 57 will produce a force which causes the friction clutch 78 to permit the shaft 52 and roller 57 thereon to freewheel while the one way spring clutuch 84 allows shaft 53 and roller 57 thereon to freewheel. The moving document thereby drives the rollers 56, 57 at the higher speed while the leading edge of the document is guided by the inclined document guide 43 into the entrance end of the semi-automatic feeding mechanism.

As the document 115 passes the photosensor 30 and contacts the entrance gate 32 of the semi-automatic feeding mechanism 24, the photosensor 30 causes a signal to be sent from the copier control circuit 18 to the automatic document feeding device control circuit 112 to deactivate the motor drive 60. However, the angular momentum of document drive mechanism 46 will continue to rotate the shafts 54, 55 and their roller 58, 59 for a short period of time to buckle the document 115 as shown in Figure 14 since the distance from the rollers 58, 59 to the entrance gate 32 is less than the distance between the leading and trailing edges of the document. This buckling insures positive engagement between the leading edge of the document 115 and the entrance gate 32.

The operator must then deactivate a semi-automatic feeding start switch (not shown) in the copier control circuit 18 which activates the semiautomatic feeding mechanism 24. After this activation, the entrance gate 32 is lifted from its position blocking the leading edge of the document 115.

Concurrently, the main document belt drive 34 is activated and thereby drives the shaft 26 and the rollers 28 drop into driving contact with the document 115 to push it forwardly to the main document belt drive 34 to feed it through the copying apparatus 12.

As a result of the activation of the main document belt drive 34, the control circuits 18 and 112 activate the motor 60 and thereby the document drive mechanism 46 to feed another document 122 from the top of stack 85 (Figure 15). When the photosensor 30 senses the trailing end of the document 115, the entrance gate 32 drops into the feed path and the rollers 28 lift therefrom. As seen in Figure 16, the automatic document feeding device 10 and the feeding mechanism 24 of the copying apparatus 12 continue to feed the documents from the stack 85 through the copying apparatus 12 to the exit tray 124. When the stack is exhausted, the supply of power from the copying apparatus 12 to the automatic document feeding device 10 is discontinued by control circuits 18 and 112 as the main document belt drive 34 of the semi-automatic feeding mechanism 24 feeds the last document to exit tray 124.

The frame can be releasably fastened on the end of the main housing by conventional fastening elements, including sheet metal screws, machine screws and cooperating nuts, adhesives, clamps and the like.

It should be noted that the automatic sheet feeding device can feed various weights, surface finishes, styles, and sizes of sheet material including letter and legal size paper, envelopes, forms and the like. It is contemplated that the single roller on each of the extending shafts can be replaced by two or more rollers.

It should also be understood that the automatic feeding device can be used in combination with sheet processing machines other than copiers, such as a printer or the like, having a sheet feeding or transport mechanism. In a printer, the sheets can be squared at the second set of rollers by use of a multiplicity of rollers on each of the shafts extending between the side plates of the frame. A cam and switch on one of the extending shafts can control the rollers/shaft combinations to run in reverse or stop, then restart the same to continue the feed.

Thus, it can be seen from the foregoing detailed specification and accompanying drawings that the efficiency of the associated business machine and its operator is greatly increased by the provision of the above-described and illustrated automatic sheet feeding device. The automatic sheet feeding device sequentially advances a single sheet from a stack of sheet material therein to a sheet transport mechanism of the business machine. Document jams may be easily cleared by pivoting the cover of the device to its open position.

Claims (32)

CLAIMS:

1. An automatic sheet feeding device comprising: A. a frame including a pair of upstanding side plates; B. an inclined tray supported in said frame adapted to hold a stack of sheets; and C. sheet drive means supported on said frame for advancing a single sheet from a stack of sheets located on said tray, said sheet drive means including:: i. a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said tray adapted to receive sheets of sheet material supported on said tray, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon; ii. gear drive means mounted on said frame outwardly of one of said side plates and including gears on said shafts of said upper and lower roller means, said gear on said upper drive shaft being engaged therewith and said gear on said lower drive shaft being normally disengaged therefrom; and iii. ciutch means mounted on said shaft of said lower roller means and operatively connected to said gear thereon, whereby said clutch means will drivingly engage said lower roller shaft with its gear and thereby said gear drive means when two or more sheets are fed simultaneously from said tray into said nip defined by said upper and lower roller means; D. motor means on said frame for rotatably driving said gear drive means; E. circuit means for said motor means adapted to be electrically connected to the associated sheet processing apparatus for controlling supply of power to said motor means for actuating said sheet drive means in response to operation of the feeding mechanism of the associated sheet processing apparatus; F. a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing of sheet jams; and G. roller separating means on said frame cooperating with said cover and said roller shafts to separate said set of roller means when said cover is pivoted from its closed position to its open position.

2. An automatic sheet feeding device as claimed in claim 1 wherein said roller separating means includes: i. an elongated aperture in the other of said side plates; ii. a slide plate having an inclined slot therein, said upper roller shaft being disposed in said elongated aperture and said inclined slot for movement therein to separate said upper and lower means; and iii. means operatively connecting said cover and said slide plate for moving said slide plate relative to said other side plate in response to pivotal movement of said cover, whereby said upper roller shaft will move upwardly in said inclined a slot in response to said pivotal movement of said cover.

3. An automatic sheet feeding device as claimed in claim 2 wherein said roller separating means includes means biasing said end of said up per roller shaft towards said lower roller shaft to provide surface engagement between said rollers thereon.

4. An automatic sheet feeding device as claimed in claim 2 or 3 wherein said sheet drive means includes a second set of upper and lower roller means defining a nip spaced from said first set of roller means, said upper and lower roller means of said second set each including a shaft extending through and journalled for rotation in said side plates and having at least one roller thereon.

5. An automatic sheet feeding device as claimed in claims wherein said roller separating means includes a second inclined cam slot in said slide plate, said other side plate having a second elongated aperture therein, said shaft of said second upper roller means being disposed in said second inclined slot and said second elongated aperture for movement therein to separate said second set of upper and lower roller means, whereby said second upper roller shaft will move upwardly in said inclined slot in response to said pivotal movement of said cover.

6. An automatic sheet feeding device as claimed in any preceding claim wherein said sheet drive means includes a second set of upper and lower roller means defining a nip spaced from said first set of roller means, said upper and lower roller means of said second set each including a shaft extending through and journalled for rotation in said side plates and having at least one roller thereon.

7. An automatic sheet feeding device as claimed in claim 6 wherein said gear drive means includes gear on said shafts of said second set of upper and lower roller means, said gear drive means driving said first and second set of roller means at a one to three surface speed ratio, and wherein said sheet drive means includes a oneway clutch mounted on an end of said shaft of said first upper roller means and operatively connected to said gear thereon, whereby said one-way clutch allows said first upper roller means to be driven faster at the speed imparted through a sheet in said first nip and being driven faster by said second set of roller means.

8. An automatic sheet feeding device as claimed in claim 6 or 7 wherein said shafts, rollers and gears of said first and second sets of roller means are provided with removable connection means to facilitate removal and replacement of said rollers.

9. A sheet processing apparatus in combination with an automatic sheet feeding device; comprising: A. sheet processing apparatus having a processing station, a feeding mechanism for feeding sheets from an entrance position through said processing station, and an electrical circuit including control means; and B. an automatic sheet feeding device including: i. a frame including a pair of upstanding side plates mounted on said processing apparatus; ii. an inclined sheet tray supported in said frame and adapted to hold a stack of sheets therein; iii. sheet drive means supported on said frame for advancing a single sheet from a stack of sheets located on said sheet tray to said entrance position of said feeding mechanism, said sheet drive means including a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said sheet tray adapted to receive sheets of paper, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon, gear drive means mounted on said frame outwardly of one of said side plates and including gears on said shafts of said upper and lower roller means, said gear on said upper drive shaft being engaged therewith and said gear on said lower drive shaft being normally disengaged therefrom, and clutch means mounted on said shaft of said lower roller means and operatively connected to said gear thereon, whereby said clutch means will drivingly engage said lower roller shaft with its gear and thereby said gear drive means when two or more sheets are fed simultaneously from said tray into said nip defined by said upper and lower roller means; iv. motor means on said frame for rotatably driving said gear drive means;; v. circuit means for said motor means electrically connected to said electrical circuit of said sheet processing apparatus for controlling supply of power to said motor means for actuating said sheet drive means in response to operation of the feeding mechanism of said sheet processing apparatus by said control means thereof; vi. a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing sheet jams; and vii. roller separating means on said frame cooperating with said cover and said roller shafts to separate said set of roller means when said cover is pivoted from its closed position to its open position.

10. The combination in accordance with claim 9 wherein said sheet drive means includes a second set of upper and lower roller means defining a nip spaced from said first set of said upper and lower roller means of said second set each including a shaft extending through and journalled for rotation in said side plates and having at least one roller thereon.

11. The combination in accordance with claim 10 wherein said second set of upper and lower roller means and said entrance position are spaced apart a distance less than the length between the trailing and leading edges of the sheets to be fed.

12. The combination in accordance with claim 11 wherein said control circuit in said feeding mechanism of said sheet processing apparatus has sheet sensing means adjacent said entrance position to detect a sheet at said entrance position and signal said circuit means of said sheet feeding apparatus to discontinue supply of power to said motor means.

13. A copying apparatus in combination with an automatic document feeding device; comprising: A. a copying apparatus having a copying station, feeding mechanism for feeding documents from an entrance position through said copying station, and an electrical circuit including control means; and B. an automatic document feeding device including:: i. a frame including a pair of upstanding side plates mounted on said copying apparatus; ii. an inclined document tray supported in said frame and adapted to hold a stack of documents; iii. document drive means supported on said frame for advancing a single document from a stack of documents located on document tray to said entrance position of said feeding mechanism, said document drive means including a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said document tray adapted to receive documents supported on said tray, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon, gear drive means mounted on said frame outwardly of one of said side plates and including gears on said shafts of said upper and lower roller means, said gear on said upper drive shaft being engaged therewith and said gear on said lower drive shaft being normally disengaged therefrom, and clutch means mounted on said shaft of said lower roller means and operatively connected to said gear thereon, whereby said clutch means will drivingly engage said lower roller shaft with its gear and thereby said gear drive means when two or more documents are fed simultaneously from said tray into said nip defined by said upper and lower roller means; iv. motor means on said frame for rotatably driving said gear drive means;; v. circuit means for said motor means electrically connected to said electrical circuit of said copying apparatus for controlling supply of power to said motor means for actuating said document drive means in response to operation of the feeding mechanism of said copying apparatus by said control means thereof; vi. a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing of document jams; and vii. roller separating means on said frame cooperating with said cover and said roller shafts to separate said set of roller means when said cover is pivoted from its closed position to its open position.

14. The combination in accordance with claim 13 wherein said document drive means includes a second set of upper and lower roller means defining a nip spaced from said first set of roller means, said upper and lower roller means of said second set each including a shaft extending through and journalled for rotation in said side plates and having at least one roller thereon.

15. The combination in accordance with claim 14 wherein said second set of upper and lower roller means and said entrance are spaced apart a distance less than the length between the trailing and leading edges of the documents to be fed.

16. The combination in accordance with claim 15 wherein said control circuit in said feeding mechanism of said copying apparatus has a document sensing means adjacent said entrance position to detect a document at said entrance position and signal said circuit means of said document feeding device to discontinue supply of power to said motor means.

17. The combination in accordance with any one of claims 13 to 16 wherein said circuit means of said document feeding device includes a switch operatively connected to said roller separating means to discontinue supply of power from said copying apparatus to said motor means when said document cover is in its open position.

18. The combination in accordance with any one of claims 13 to 16 wherein said circuit means includes a manually operated switch for supplying power to said motor means.

19. A sheet processing apparatus in combination with an automatic sheet feeding device; comprising: A. a sheet processing apparatus including: i. a processing station; ii. a feeding mechanism having roller means, having an entrance gate, and a main sheet moving belt drive means for moving a sheet of material from an entrance position at said entrance gate through said processing station; iii. an electrical circuit including control means having a sheet sensing means detect a sheet at said entrance position; B. an automatic sheet feeding device comprising:: i. a frame including a pair of upstanding side plates mounted on said processing apparatus; ii. a sheet tray supported in said frame and adapted to hold a stack of sheets therein; iii. sheet drive means supported on said frame for advancing a single sheet from a stack of sheets located on said sheet tray to said entrance position of said feeding mechanism, said sheet drive means including a set of upper and lower roller means cooperating to form a nip adjacent the lower edge of said sheet tray adapted to receive sheets of paper, said upper and lower roller means each including a shaft extending through and journalled for rotation in said side plates of said frame and at least one roller mounted thereon, roller drive means mounted on said frame for driving said roller means, and clutch means operatively connected between said lower roller means and said roller drive means, whereby said clutch means will drivingly engage said lower roller shaft when two or more sheets are fed simultaneously from said tray into said nip defined by said upper nd lower roller means; iv. motor means on said frame for driving said roller drive means; v. circuit means for said motor means electrically connected to said electrical circuit of said sheet processing apparatus for controlling supply of power to said motor means for actuating said sheet drive means in response to operation of the feeding mechanism of said sheet processing apparatus by said control means thereof.

20. The combination in accordance with claim 19 wherein said sheet sensing means of said sheet processing apparatus is adjacent said entrance position to detect a sheet at said entrance position and signal said circuit means of said automatic sheet feeding device to discontinue supply of power of said motor means.

21. The combination in accordance with claim 19 or 20 wherein said entrance gate is mounted for vertical movemet for blocking and releasing a sheet of material in said entrance position.

22. The combination in accordance with claim 21 wherein said upper roller means is mounted for vertical movement and is mechanically coupled to said entrance gate whereby said entrance gate and said upper roller means operate in unison.

23. The combination in accordance with any one of claims 19 to 22 wherein said main belt drive means and said upper roller means are mechanically coupled for simultaneous operation to feed a sheet from said entrance position through said processing station.

24. The combination in accordance with any one of claims 19 to 23 wherein said sheet processing apparatus is a copying apparatus and said upper roller means, said entrance gate and said main belt drive means are mounted in a pivoted cover for a copying station.

25. The combination in accordance with any one of claims 19 to 24 further including a cover journalled in said frame for pivotal movement between a closed position and an open position to permit clearing of sheet jams.

26. The combination in accordance with claim 25 further including roller separating means on said frame cooperating with said cover and said roller shafts to separate said upper and lower roller means when said cover is pivoted from its closed position to its open position.

27. The combination in accordance with claim 26 wherein said roller separating means includes: i. an elongated aperture in said frame on one of said side plates; ii. a slide plate having an inclined slot therein, said upper roller shaft being disposed in said elongated aperture and said inclined slot for movement therein to separate said upper and lower roller means; and iii. means operatively connecting said cover and said slide plate for moving said slide plate relative to said one side plate in response to pivotal movement of said cover, whereby said upper roller shaft will move upwardly in said inclined slot in response to said pivotal movement of said cover.

28. The combination in accordance with claim 27 wherein said roller separating means further includes means biasing said end of said upper roller shaft towards said lower roller shaft to provide surface engagement between said rollers thereon.

29. The combination in accordance with any one of claims 19 to 28 wherein said sheet drive means includes a second set of upper and lower roller means defining a nip spaced from said first set of roller means, said upper and lower roller means of said second set each including a shaft extending through and journalled for rotation in said side plates and having at least one roller thereon.

30. The combination in accordance with claim 29 wherein said second set of upper and lower roller means and said entrance position are spaced apart a distance less than the length between the trailing and leading edges of the sheets to be fed.

31. An automatic document feeding device substantially as described with reference to and as illustrated in the accompanying drawings.

32. A copying apparatus in combination with an automatic document feeding device substantially as described with reference to and as illustrated in the accompanying drawings.