WO1987002972A1

WO1987002972A1 - Document feed device

Info

Publication number: WO1987002972A1
Application number: PCT/AU1986/000345
Authority: WO
Inventors: Robert John Grace
Original assignee: Cameronics Technology Corporation Limited
Priority date: 1985-11-14
Filing date: 1986-11-13
Publication date: 1987-05-21

Abstract

A document feed device comprises a frame (1), a feed tray (2), a receiving tray (3), a transparent platten (5) positioned at an exposure station on a photocopier and includes a photocell (45) to control movement of the document from the photocopier and a transport belt (6) over the transparent platten (5), characterised by a first document feed roller (28) arranged to feed a document to be copied to a second feed roller (29) with a skid plate (33) pressing the document to the second feed roller (29), counter feed wheels (37, 38) to counter forward movement of more than one document at a time and a register gate (47) urged into a position to engage the leading edge of the document to stop movement of the document on the transparent platten (5) when an exposure is to occur.

Description

DOCUMENT FEED DEVICE

This invention relates to an improved document feed device for photocopying machines and the like where it is necessary to feed a series of originals onto the machine and to copy each original either 5. once or a number of times, according to requirements.

The invention also relates to a method of feeding documents .

It is already well known to provide document feed devices on photocopy machines and the like, which

10. devices are integrated with the machine and are so arranged that the original which is to be copied is placed on to an input tray and is fed from the tray to the copy machine and the required number of copies made, and then the original is moved away from the

15. machine to a receiving tray.

It can be very time consuming to manually feed such machines which are not so equipped. It is there¬ fore highly advantageous to be able to place a series of original documents which are to be copied into

20. a device which will sucessively feed them through the copy machine to have the necessary copies made, and it has been proposed heretofore to use attachments for such machines which can be placed on to a photo¬ copy machine over the illuminated window to provide

25. a separate unit which can be used as required. A typical example of such prior art is given in the specification of United States Letters Patent No. 3,623,806' in the name of JEROME M SHORT, assigned to Minnesota Mining and Manufacturing Co., which dev-

30. ice includes an inclined feed tray adapted to receive the documents which are to be copied and from which the documents are fed into a channel having driving rollers to engage the document and transfer it over a window which fits over the exposure station of the photocopier and from there through guide means by 5. means of rollers into a receiving tray, the functions being electronically timed from the photocopier to achieve the necessary synchronization.

Reference is also made to an earlier invention by the same Inventor published under International 10. Publication Number WO 81/00246 which advanced the prior art by using light timing from the photocopier.

An object of the present invention is to provide an improved form of document feed device which will be more effective in its operation.

15. Other objects will be apparent from the following description.

A document feed device according to this invention comprises a frame, a feed tray and a receiving tray supported on said frame adapted to hold

20. documents being copied, a transparent platten on the frame adapted to be positioned at an exposure station on a photocopier, means to move a document from the feed tray on to the transparent platten and from it to the receiving tray, a photocell to control movement of

25. the document from light from a photocopying machine, the transport mechanism having a transport belt passing around rollers which position the belt over the transparent platten to form a channel in which the document is moved by differential friction between the

5. document and the belt and the transparent platten when the belt is driven, characterised by a first document feed roller arranged to engage and feed a document to be copied to a second feed roller, a skid plate to press the document from the feed tray to the second

10. feed roller, means to rotate the second feed roller to move the document into the nip between the belt and the transparent platten, means associated with the second roller to prevent forward movement of more than one document on the belt, means to move the belt to

15. position the document over the transparent platten, a register gate urged into a position to stop movement of the document en the transparent platten, means to withdraw the register gate to allow the document to be moved, and means to transport the document to the

20. document receiving tray after exposure.

The mechanism is thus arranged to feed a document from the feed tray to the holding position where its leading edge is in contact with the register gate, this occurring when the document feed is first 25. switched on, or each time that the belt is actuated to feed a document. Because the movement of the document is effected by the differential friction, accurate register is possible by using a register gate which is projected up into the path of the document to hold the document

5. when the correct register occurs, the belt allowing sufficient slip during a slight over-run of the belt, but the register gate is arranged to be lowered when the document is to be fed to the receiving tray by the secondary document transport means. After the

10. document is released the gate is urged to its operative petition against the document as it slides over the gate to move back into position to act as indexing means for the next document.

The method comprises placing the documents to

15. be copied into the receiving tray, feeding the topmost document from the feed ^'tray by engaging the document by means of a resilient rcller, driving the roller to move the document forward a selected distance, releasing the document from the first feed roller,

20. further moving the document by means of a second feed roller into a channel formed between a belt and a transparent platten, allowing the second feed roller to over-run the document as the document is pulled forward by the belt frictionally engaging the document

25. and moving it over the transparent platten between which the document there is less friction than between the document and the belt, stopping the forward move¬ ment of the document by a registration gate and termin¬ ating the drive of the belt while effecting an expos-

30. ure by means of the copying machine, withdrawing the registration gate to allow the document to be moved from the transparent platten while driving the belts, guiding the document to the receiving tray. The method is further characterised by rotating counter feed wheels disposed to engage the document being fed by the first to the second feed roller, and driving the counter feed wheels in the opposite 5. direction to the second feed wheel whereby to retain in the feed tray any document which is located beneath the document being fed.

To enable the invention to be fully understood, an embodiment thereof will now be described with refer- 10. ence to the accompanying drawings in which,

FIG. 1 is a schematic sectional side elevation of the invention as on line 1-1 of FIG. 2 illustrating the arrangement of the components of the feed device,

FIG. 2 is a sectional plan on line 2-2 of FIG. 15. 1,

FIG. 3 is an enlarged schematic end elevation of the document feed device as on line 3-3 of FIG. 1, and

FIG. 4 is an enlarged fragmentary side elevation 20. of the registration gate showing at A and B the different position of the gate.

The frame 1 of the machine carries on it a docu¬ ment feed tray 2 and a document receiving tray 3, the feed tray 2 being inclined so that the documents 25. can be readily fed from the tray by document advance means, the document receiving tray 3 being positioned generally horizontally to receive the documents which have been copied.

The frame 1 on the machine has in it a window 4 in which is disposed a transparent platten 5 which, when the machine is positioned on a photocopier or 5. like machine, registers with the window of the expos¬ ure station of the photocopier or like machine so that illumination from the photocopier or like machine passing through the window would also pass through the transparent platten 5.

10. Disposed over the transparent platten 5 is a transport belt 6 formed of fabric and of a nature such that the belt 6 tends to grip documents which are tc be transported over the transparent platten 5, the belt being formed in four or other number of

15. side-by-side sections A, B, and C as shown particul¬ arly in FIG. 2. The belt passes around rollers 7 and 8, the first roller 7 being positioned adjacent to the first end of the transparent platten 5 and the sec¬ ond roller 8 being positioned adjacent the second

20. end of the transparent platten 5 so that the belt 6 which passes around these rollers 7 and 8 moves over the platten 5 when the roller 8 is driven. The rollers are supported in bearings by the frame 1.

At the output end 9 of the transparent platten 25. 5 is a guide 10 which extends from near the end of the transparent platten 5 and at its commencement is co- planar therewith but follows the belt 6 where it passes around the second roller 8 and extends upwardly to terminate adjacent to roller 12 supported from the 7

frame 1 which forms a secondary transport device which has a brush 13 in contact with it so that when a docu¬ ment is guided upwardly by the guide 10 to the second¬ ary drive roller 12, this roller 12 will move the 5.- document upwards against a further guide 14 carried by the frame 1 and positioned to discharge it into the document receiving tray 3.

The drive to the rollers 8 and 12 is obtained from a motor 15 and gear box 16 which rotates a pair

10. of pulleys 17 and 18, the pulley 17 being coupled by means of the belt 19 to a pulley 20 on a clutch mechanism 21, the clutch mechanism 21 in turn, when engaged, driving the second roller 8 from the pulley 22 through the belt 25, the pulley 18 on the shaft

15. of the gear box 16 also driving the secondary trans¬ port roller 12 through the belt 24.

The document advance mechanism 27 comprises a feed roller 28 set to move the documents from the docu¬ ment feed tray 2 to the belt 6 ready for moving onto 20. the transparent platten in order to be copied.

The feed wheel 28 is a segment yp'e wheel with only part of the usual 360 circumference, say 200 , and is composed of a soft rubber or similar resilient material. This segmented first feed wheel 28 is posi- 25. tioned just over the topmost document in the document feed tray 2 and presses down onto the document and pushes it out of the tray 2 to a second feed roller 29. The segmented feed wheel 28 is driven by a motor 30 to complete one revolution for each sheet fed for- 5- ward. On coming to rest after the one revolution the flat part 31 of the roller is away from the docu¬ ment so as not to impede its further progress.

The second feed roller 29 is positioned adjacent to the edge 32 of the document feed tray. This second

10. feed roller 29 rotates against a skid plate 33 which is below the second feed roller 29 and which has a coating of a material with a very low co-efficient of friction, preferably a product known as 'Teflon' , which is used for slipping clutches, the purpose of

15. this system being to assist in advancing documents of varied sizes and thicknesses from the same pile, down to the nip between the belt 6 and the transparent platten 5. The second feed roller 29 is rotated by means of a motor 34 turned on by a control circuit for

20. a short period of time so that the document is pushed into the nip between the belt 6 and the transparent platten 5.

To prevent feeding more than one sheet at a time, a counter feed wheel assembly 36 is positioned lower 25. than, and on each side of, the second feed roller 29, a preferred system being two wheels 37 and 38 which are placed either side and just below the second feed roller 29 and skid plate 33 arrangement, but rotating in the same direction as the second feed roller 29 although under the document. The purpose of this counter feed wheel arrangement is to hold back the

5. lower document in the feed tra}^r 2, thus only the top¬ most document can be fed to the second feed roller 29. Double feed occurs occasionally due to static build-up between sheets, or other causes of adhesion such as dirt, grease, etc. or by pressure. The counter feed

10. wheels 37 and 38 are positioned ahead of the second feed roller 29 so far as document travel is concerned to ensure that the document cannot reach the nip between the skid plate 33 and the second feed roller 29.

15. The second feed roller 29 is driven by the mctor 34, and the shaft 39 on which the feed roller 29 is mcunted has a drive chain 40 connecting a sprocket on the shaft of the motor 34 with the shaft 41 on which the counter feed wheels 37 and 38 are- carried but a

20. one-way clutch 42 is provided to allow the second feed roller 29 to ever-run the drive when the belt 6 moves a sheet forward. Thus the segmented first feed roller 28 starts the pάiper moving fcrward to the second feed reHer 29 which continues to feed the paper into the

25. nip of the belt 6 and the transparent platten 5, and, when the belt 6 moves forward, the paper can move beneath the. second feed roller 29 by, if necessary, over-drivirg the second feed roller 29, this being permitted by the clutch 42. The photo-cell 45 is arranged at the longitudinal centre of the platten, and energization of the photo— cell by the illuminating means within the photocopier is the only connection necessary with the photocopier so that the document feed unit does not require any electrical or mechanical connection whatever to the photocopier, the whole of the regulation of the docu¬ ment feed being under control of the light which reach¬ es the photo-cell 45 froci the photocopier.

10 To ensure that the documents are stopped correct¬ ly in the guide channeZ at the exposure station a register gate 47 is carried on a transverse bar 48.

When a load switch not shown, is actuated, the segmented first feed roller 28 is rotated for one ι revolution and, this mcves the topmost document forward to the second feed roller 28.

The feed roller 28 can be mounted on an arm 50 connected by a pivot 51 assembly to the frame 1 tc allow the height of the feed roller 28 tc be adjusted 2_Q for different thicknesses of the pile of copy material being fed.

At this stage the motor 15 is running and is rotating the secondary transport roller 12 in readi¬ ness to move a sheet leaving the document guide chan- 25. nel into the document receiving tray 3. When a second switch, which we term the "set" button, also not shown, is actuated the clutch 21, which is of the electromagnetic type, is actuated momentarily to connect the drive to the roller 8,

5. and this in turn drives the belt 6 to transport the document which has its leading edge engaged in the nip, along the document guide channel between the belt 6 and the platten 5, until its leading edge strik¬ es the registration gate 47 to stop the forward move-

10. ment at about the time that the drive to the belt 6 stops, the clutch 21 preferably being disengaged about 0.3 seconds after the document is stopped by the registration gate 47, this delay being controlled by a timing function of known type on a control board

15. 52.

The machine is now ready for the copy machine to commence the photocopying cycle.

As the illumination source of the photocopier machine passes under the centre of the document feed,

20. the photocell 45 senses the light and a signal is sent to the control board and, after a brief time delay which is adjustable to suit varying speeds of photocopier cycle times, and is necessary when the illumination source of the photocopier traverses the

25. platten so as to ensure that the belt is not energized until a scan is completed, a control board relay is activated and causes the solenoid 49 to lower the registration gate 47, and simultaneously the clutch 21 is engaged to transport the document away from the

30 exposure station, the document being directed along the curved path defined by the guide 10 which curves around the roller 8 tc the secondary document drive transport roller 12 by means of which, assisted by the pressure brush 13, the document is moved rapidly 5- into the document receiving tray 3.

While the just referred to document is being fed out of the zone of the platten 5, that is the exposure zone, the next document to be copied, which has been waiting in the nip between the belt 6 and 10. the platten 5 is drawn down on to the platten 5 and moved by the belt 6 into the exposure station where it is held against further movement by the regist¬ ration gate 47.

The registration gate is lowere.d before the first 15. document is moved out, but is then allowed to ride against the paper by spring pressure after de-energiz¬ ation of a solenoid 49 which occurs as the document commences tc move out of this area, the gate rising into the locating position ready to register the next 20. document which would normally be following close be¬ hind.

The register gate 47 has its "up" position shown at A of FIG. 4, while at B is shown the "down" pos¬ ition of the gate.

25. In the case of multiple copies being required, a counter is set for the particular number, and the control board registers that number of light passes via the sensor before activating the clutch to change documents.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:-

1. A document feed device comprising a frame (1), a feed tray (2) and a receiving tray [ ^{' )} support¬ ed on said frame (1) adapted to hold documents being copied, a transparent platten (5) on said frame (1)

5. adapted to be positioned at an exposure station on a photocopier, means to move a document from the feed tray (2) on to the transparent platten (5) and from it to the receiving tray (3), and a photocell to control movement of the document activated by light

10. from a photocopying machine, the transport mechanism having a transport belt (6) passing around rollers (7-8) to position the belt (6) over the transparent platten (5) to form a channel in which the document is moved by differential friction between the

15. document and the belt (6) and the transparent platten (5), characterised" by a first document feed roller (28) arranged to engage and feed a document to be copied to a second feed roller (29), a skid plate (33) to press the document from the feed tray (2) to

20. the second feed roller (29), means to rotate the second feed roller (28) to move the document over the skid plate (33) into the nip between the belt (6) and the transparent platten (5) and into the channel, means associated with the second feed roller (29) to

25. prevent forward movement of more than one document by the said belt, under (15-16) means to move the belt to position the document over the said transparent platten (5), a register gate (47) urged into a position to engage the leading edge of the document

30 __ to stop movement of the document on the transparent platten (5), means to withdraw the register gate (47) to allow the document to move, and means (10,12) to transport the document to the document receiving tray (3) after exposure. 2. An improved document feed device according to claim 1 characterised in that the first feed roll¬ er (28) is positioned across the feed tray (2) and has a flat surface (31) along its length, and by

5. driving means (30) to cause the first feed roller

(28) to rotate through one revolution from a position where the flat surface (31) faces a document in the feed tray (2) to a position where rotation of the first feed roller (28) engages and drives the topmost

10. document forward into contact with a second feed roller (29) positioned in the direction of travel of the document under influence of the first feed roller (28) whereby a document is fed forward to be engaged by the second feed roller (29) and the first feed

15. roller (28) is disengaged from the document.

3. An improved document feed device according to claim 2 wherein a pair of counter feed wheels (37,38) are mounted on a shaft (41) to be positioned one on each side of the second feed roller (29) but

5. at a lower level and outside of the skid plate (33) to project into the path of a document as it is fed toward the second feed roller, means (40) to rotate the counter feed wheels (37-38) in the same direction as the second feed roller (29) whereby a document 10. beneath the selected document is restrained against forward movement by the oppositely moving peripheries of the counter feed wheels 37. 4. An improved document feed device according to claim 3 wherein the second feed roller (29) in¬ cludes clutch means (42) in its drive to permit the second feed roller (29) to over-run the drive after

5. the document has been fed by the second feed roller (29) into engagement with the belt (6) to move the document along the channel to its position where it is located over the transparent platten (5).

5. An improved document feed device according to claim 4 wherein the second feed roller (29) is carried on a shaft having its bearings supported by the frame (1) and is driven by a motor (34) thro- 5. ugh an over-run clutch (42) on the shaft, and the counter feed wheels (37,38) are carried on a shaft (41) having its bearings carried by the frame (1), and wherein the shaft (41) of the^' counter feed wheels (37,38) is coupled to the shaft (39) of the second 10. feed roller (29) by drive means to cause both shafts (39 and 41) to rotate in the same direction.

6. A document feed device according to claim

1 characterised by a registration gate (47) disposed at the end portion of the transparent platten in relation to the travel of the document and adapted

5. -to move to project above the surface of the platten (5) to engage the edge of a document fed along the platten (5) by the belt (6) said registration gate (47) being mounted on a transverse bar ⁽48) supported in the frame (1) of the document feed device, and

10. means (49) to rock the transverse bar to withdraw the registration gate (47) from the path of the docu¬ ment when the document is to be moved to the receiv¬ ing tray (3) .

7. A document feed device according to claim 5 wherein the registration gate (47) has a leading edge projecting from the transverse bar (48) and the registration gate (47) is urged to project into

5. the path of the document to engage the leading edge of the document.

8. A document feed device according to claim 2 wherein the transparent platten (5) is carried at the base of the frame (1), the receiving tray is carried by the frame to have a discharge edge

5. (32) directed toward a first end of the transparent platten (5), the skid plate (33) extends from the edge (32) toward the transparent platten (5) but is narrower than the feed tray, the second feed roller (29) is carried on a shaft (39) above the skid plate

10. (33) the second feed roller (29) presses on the skid plate (33), the counter feed wheels (37,38) are carried on a shaft (41) below the skid plate (33) and are disposed one on each side of the skid plate (33) .

9. The method of feeding a document through a document feed device in which a document is to be fed from a feed tray (2) to a receiving tray (3) over a transparent platten (5) adapted to be register- 5. ed with an exposure station of a photocopier, the method comprising placing the documents to be copied into the receiving tray (2), feeding the topmost document from the feed tray (2) by engaging the docu¬ ment by means of a resilient roller (28), driving

10. the roller (28) to move the document forward a select¬ ed distance, releasing the document from the first feed roller (28), further moving the document by means of a second feed roller (29) into a channel formed between a belt (6) and a transparent platten

15. (5), allowing the second feed roller (29) to over-run its drive as the document is pulled forward by the _ belt (6) frictionally engaging the document and mov¬ ing it over the transparent platten (5) between which the document there is less friction than between

20. the document and the belt, stopping the forward move¬ ment of the document by a registration gate (47) and terminating the drive (15,16) of the belt (6) while effecting an exposure by means of the copying machine, withdrawing the registration gate (47) to

25. allow the document to be moved from the transparent platten (5), driving the belt (6) and, guiding the document to the receiving tray (3).

10. The method of claim 9 characterised by rotating counter feed wheels (37,38) disposed to engage the document being fed by the first feed roll¬ er (28), and driving the counter feed wheels (37,38) 5. in the opposite direction to the second feed wheel (29) whereby to retain in the feed tray (2) a docu¬ ment positioned beneath the document being fed from the trav. 11. The method of claim 9 wherein the counter feed wheels (37,38) are engaged on the underside of a document being fed forward by the first feed wheel (28) before the leading edge of the document reaches the second feed wheel (29) whereby to prevent a document beneath the document being fed from reach¬ ing the nip between the skid plate (33) and the sec¬ ond feed wheel (29).