DOCUMENT FEED

Abstract: An automatic document feed device for hand-fed photocopy machines in which documents to be copied are fed from a feed tray (2) to a receiving tray (3) over a transparent platten (5) which is arranged to register with the illuminated exposure station of the photocopier, characterized by a transport belt (7) of higher friction coefficient than the platten arranged to draw the document over the platten, including document pick-up means (4) to feed a document from the feed tray (2) to the transport belt (7) and secondary transport means (20) to feed the document from the transport belt (7) to the receiving tray (3) and including register pins (52) and driving means (25, 43) for the document pick-up means and for the transport belt (7) and for the secondary transport means (20) further characterized by light-sensitive means (50) arranged to cause the transport belt (7) to be driven through means which move the transport belt (7) forward each time the light-sensitive means (50) are illuminated by the illumination from the photocopy machine excepting when effecting multicopying when the transport belt (7) is not driven after a document is positioned on the platten until the necessary number of copies have been made, whereby no mechanical or electrical synchronization connection is required between the document feed and the photocopy machine.

Description: "DOCUMENT FEED" This invention relates to a document feed, and in particular relates to a document feed device for photo¬ copying machines and the like where it is necessary to feed a series of originals into the machine and to copy each original either once or a number of times, accord¬ ing to requirements . It is already wellknown to provide document feeds on photocopy machines and the like, which devices are integrated with the machine and are so arranged that the original which is to be copied is placed on to a receiving tray and is fed from the tray to the copy machine and the required number of copies made, and then the original is moved up out of the machine to a receiving tray. To manually feed such machines which are not so equipped can be very time-consuming. It is therefore highly advantageous to be able to place a series of original documents which are to be copied into a device which will successively 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 photocopy machine over the illuminated window to provide 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 Manu¬ facturing Co, which device 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 means of rollers into a receiv¬ ing tray, the functions being electronically timed from the photocopier to achieve the necessary synchronization. An object of the present invention is to provide an improved form of document feed which will be effect¬ ive in its operation and which is so constructed that it is only necessary to position the document feed on a photocopier or similar machine without having to make mechanical or electrical connections to the photocopy machine itself so that the photocopying machine can be left in an unaltered state. The present invention thus relates generally to a document feed which comprises a frame supporting a feed tray and a receiving tray which are adapted to hold documents being copied, the machine including a trans¬ parent platten at an exposure station and means to guide a document from the feed tray to the exposure station and from the exposure station to the receiving tray, including means to synchronize the movement of the document with the photocopying machine, the present invention being characterized by document pick-up means adjacent to the discharge end of a feed tray which are arranged to feed documents consecutively to a transport mechanism arranged to position the document over the exposure window at the exposure station of the photo¬ copier or the like, the transport mechanism comprising a transport belt, preferably arranged in parallel sec- tions, passing around rollers to position the belt over the window of the exposure station, the transport belt forming with a transparent platten on the document feed a document guide channel, the belt being chosen to have a greater frictional effect on the document than that exerted by the said platten which is chosen to have a low coefficient of friction, whereby the document will be moved over the platten because of differential fric¬ tion when the belt is actuated, actuation of the belt being effected from a motor through clutch means to be at high speed and the drive being controlled by a light- sensitive device at the platten which causes the clutch to be engaged when the light source of the photocopying machine is energized or moves to illuminate the window of the photocopying machine, and thus the document to be copied, through the transparent platten of the docu¬ ment feed, the document being thus fed into position at high speed from a "holding" position to be exposed to the illumination and after exposure being removed from the window area to secondary document transport means which then transport the document to the receiving tray. 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 belt, this occurr¬ ing when the document feed is first switched on, or each time that the belt is actuated to feed a document gripped by the belt, the secondary transport means being continually actuated. Because the movement of the document is effected by the differential friction, accurate register is possible by using register pins which are projected into the path of the document to hold the document when the correct register occurs, the belt allowing sufficient slip during a slight over-run of the belt, but the register pins are arranged to be lifted when the document is to be fed to the receiving tray by the secondary document transport means but the pins can fall back on to the document as it slides under the pins to fall back in position to act as indexing means for the next document. According to a preferred embodiment of the inven¬ tion the document feed as heretofore comprises a frame supporting a feed tray and a receiving tray adapted to hold documents being copied, and having a transparent platten at an exposure station and means to guide a document from the feed tray to the exposure station, and from the exposure station to the receiving tray, including means to synchronize the movement of the docu¬ ment with a photocopying machine, characterized by, a first roller and a second roller rotationally supported on a frame one at a first and the other at a second end of a transparent platten supported in a window in the frame, a transport belt passing around the rollers positioned to extend over the back of the platten to form between the belt and the platten a document guide channel, the belt having a higher frictional effect on the document than the platten whereby to move the docu- ment over the platten when the belt is driven forwardly, a first guide extending from the first end of a platten to adjacent the docuemnt feed tray and extending part way around the belt means at the first roller, a second guide extending from the second end portion of the platten to adjacent the document receiving tray and extending part way around the belt at the second roller, document pick-up means adjacent the discharge end of the feed tray arranged to feed the lead end of a document to between the first guide means and the belt, secondary document transport means rotationally supported on the frame adjacent the receiving end of the document receiv¬ ing tray, register means projectable into the guide channel adjacent the second end of the platform, drive means for the document pick-up means, a first switch to actuate said drive means, drive means for the transport belt and the secondary drive means, a second switch to actuate the drive means, a clutch to control drive to the transport belt, and light-sensitive means at the platten to initiate drive of the belt when an exposure light of the said photocopy machine is energized where¬ by to move a document from the platten. In order however that the invention can be fully understood an embodiment thereof will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a preferred form of the document feed constructed according to this invention, Figure 2 is a somewhat schematic transverse sectional view showing the arrangement of the various components of the document feed unit, Figure 3 is a perspective view showing how a belt forms the main transport mechanism for the documents and showing also the register pins to stop the documents at the correct location and showing generally the drive assembly and document pick-up mechanism, and Figure 4 is a schematic action diagram. The frame 1 of the machine carries on it a docu¬ ment feed tray 2 and a document receiving tray 3, the former being inclined so that the documents can be readily fed from the tray by document pick-up means 4, the document receiving tray being positioned generally horizontally to receive the documents which have been copied. The frame 1 on the machine has in it a window in which is disposed a transparent platten 5 which, when the machine is positioned on a photocopy or like machine, registers with the window of the exposure station of the photocopy or -like machine so that illu¬ mination from the photocopy or like machine passing through the window would also pass through the trans¬ parent platten 5. Disposed over the transparent platten 5 is a trans¬ port belt 7 formed of fabric and of a nature such that the belt 7 tends to grip documents which " are to be trans- ported over the transparent platten 5, the belt 7 being formed in four side-by-side sections A, B, C and D, as shown more particularly in Figure 3. The belt 7 passes around rollers 8 and 9, the first roller 8 being posi¬ tioned adjacent a first end of the transparent platten 5 and the second roller 9 being positioned adjacent the second end of the transparent platten 5 so that the belt 7 which passes around these rollers moves over the platten when the roller 9 is driven. A first guide 12, attached at 13 but free at the other end 14, excepting that it rests on the platten 5, extends from the document pick-up means 4 to the first end of the transparent platten 5 and is positioned to curve around the belt 7 as it passes over the first roller 8 so that a document fed into the nip 15 between the member 12 and the belt 7 will be gripped by the belt and moved around through a guide channel 16 formed between the transparent platten 5 and the belt 7. At the other end of the transparent platten 5 is a second guide 18 which is secured"at 19 to the second end of the transparent platten to follow the belt 7 where it passes around the second roller 9 and extends upwardly to terminate adjacent a roller 20 which forms a second¬ ary transport drive which has a brush 22 in contact with it so that when a document is guided upwardly by the second guide 19 to the secondary drive roller 20, this roller 20 will move the document upwards to against the guide 23 formed by the frame l,to discharge it into the document receiving tray 3. The drive to the roller 9 is obtained from a motor 25 which rotates a pulley 26 coupled by means of the belt 27 to a pulley 28 on a clutch mechanism 30, the clutch mechanism in turn, when engaged, driving the second roller 9 from the pulley 31 through the belt 32, a pulley 33 on the shaft of the motor also driving the transport roller 20 through the belt 34. The document pick-up 4 comprises a channel-shaped housing 35 in which is movable a bar 36 to which is fixed a strip 37 of a butyl rubber substance or similar material having greater cohesion properties than adhesion properties, the strip being arranged to con¬ tact the topmost document in the document feed tray 2 when the strip 37 is pressed against the document, the bar 36 being moved by a rod 40 having on it a rack 41 engaged by a pinion 42 which is driven from a motor 43 the pinion 42 having on it an untoothed segment 44 and the motor being arranged to cause the pinion 42 to only make one revolution when energized, the arrange¬ ment being such that when the teeth of the pinion 42 engage the rack 41 the bar 36 is moved back, bringing with it a document which has been contacted by the strip 39 until the document strikes the edges 45 of the housing 35 whereupon the strip 37 in moving back is dis¬ engaged from the document and the document falls down into the nip 15 between the first guide 12 and the belt 7. After releasing the document the bar 36 is driven back further into the housing 35 and the motor 43 stops until such time as it is necessary to pick up another document from the tray 2, whereupon the motor 43 is actuated and the pinion 42 continues until the untoothed segment 44 on it coincides with the rack 41 at which stage the bar 36 through the rod 40 is pulled back by a spring 46 secured between the rod 40 and the member 47 which is fixed to the frame 1 to contact the strip 37 with the uppermost document in the document feed tray 2 but, as the pinion 42 continues to rotate, the teeth on it again engage the rack 41 and move the bar 36 back, carrying with it the lead end of a document engaged by the strip 37 until the document is released by contact with the end 45 of the housing 35. The photo-cell 50 is arranged at the longitudinal centre of the platten 5, and energization of the photo¬ cell by the illuminating means within the photocopier is the only connection which there is with the photo¬ copier 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 document feed being under control of the light which reaches the photo-cell from the photocopier, The timing will be described later. To ensure that the documents are stopped correctly in the guide channel 16 at the exposure station a pair of register pins 52 is carried on a transverse bar 53 which is actuated by a solenoid 54, in one position the pins 52 are withdrawn from out of the guide channels 16 so that a document can be discharged from the exposure station to the receiving tray 3, but in another position they are projectable down to form stops across the docu¬ ment guide channel 16 so that the document being fed for¬ ward by the transport belt 7 comes to rest at an exact register position with the transparent platten 5 of the exposure station. The register pins 52 are free to move down when not projected upwardly by the solenoid 54 to extend across the guide channel 16 but after being raised to let a document feed forward by the belt 7 the pins fall back on to the document as it moves out of the guide channel 16 to fall back in readiness to index the next document immediately the first document is out of the exposure zone. The sequence of operation of the device is as follows. The main motor 25 is energized by actuation of a suitable switch 60 before or after the original documents are inserted into the feed tray in a face-up position. The switch 60 is now moved to a second "load" position and this energizes the document pick-up mecha- nism motor 43 by causing the pinion 42 which is driven by the motor 43 to go through one revolution. As this occurs the flat 44 on the pinion 42 coincides with the rack 41 and the spring 46 pulls the bar 36 to cause the strip 37 to press momentarily against the lead sec- tion of the topmost document in the feed tray to cause the document to adhere to the strip 37 and the strip 37 is then moved back by the pinion 42 continuing and the document is released as the strip 37 passes beyond the edges 45 of the member 35, causing the document to fall down into the nip 15 between the transport belt 7 and the first guide 12 as shown by the arrow 61 in Figure 2. At this stage the motor 25 is running and is rotating the transport roller 20 in readiness to move a sheet leaving the document guide channel 16 into the document receiving tray. When a second switch 62, which we term the "set" button, is actuated the electromagnetic clutch 30 is actuated momentarily to connect the drive to the roller 9, and this in turn drives the belt 7 to transport the document which has its leading edge engaged in the nip 15, along the document guide channel until its leading edge strikes the registration pins 52 to stop the for¬ ward movement at about the time that the drive to the belt stops, the clutch preferably being disengaged about 0.3 seconds after the document is stopped by the registration pins 52, this delay being controlled by a timing function of known type on a control board 65. 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, the optical sensor 50 senses the light and a signal is sent to the control board 65 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 platten so as to ensure that the belt 7 is not ener¬ gized until a scan is completed, a control board relay is activated and causes the solenoid 54 to draw up the pins 52 of the registration gate and similtaneously the clutch 30 is engaged to transport the document away from the exposure station, the document being directed along a curved path around the roller 9 between the belt 7 and the second guide 18 to the secondary docu- ment drive transport roller 20 by means of which, assisted by the pressure brush 22, the document is moved rapidly 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 14 between the belt 7 and the first guide 12 is drawn down on to the platten and moved by the belt 7 into the exposure station where it is held against further movement by the registration pins 52. The solenoid 54 is energized before the first document is moved out, and the registration pins 52 are raised, but the pins are allowed to ride on the paper after de-energization of the solenoid which occurs as the document commences to move out of this area, the pins 52 drop down into the locating recess ready to register the next document which would normally be following close behind. In the case of multiple copies being required, a counter is set for the particular number, and the con- trol board registers that number of light passes via the sensor 50 before activating the clutch 30 to change documents. Referring to the action diagram of Figure 4. The part A of the switch 60 energizes the power input to the main motor 25 and the document pick-up motor 43, the belt control clutch 30 and the register pin solenoid 54, the three latter being switched through switching controls 67, 68 and 69 respectively, which can be relays or solid state switching devices which are in turn controlled by the switch 60B and 62 and the light- sensitive member 50 and the copy counter 66, the time delay control which ensures that the belt is not driven until the exposure has been completed being designated 70, while the time that the belt is driven to urge a document forward to contact the register pins is desig¬ nated 71. It will be realized that when the switch 60 is actuated to close the main power circuit 60A, supply is to all units, but the sequential function which is required is controlled by the switching controls 67, 68 and 69 which in turn are under control of the push button 6OB and 62 as well as the light-sensitive photo¬ electric or other cell means 50 and the time delay and time limiting controls 70 and 71 and the counter 66. To commence copying the switch 60A is closed to supply current to the various deyices and to start the motor 25 which then drives the secondary document trans¬ port roller 20 and if now the push switch 60B is actuated the document pick-up motor 43 is energized to feed a document which is to be copied to the transport belt 7. Momentary closing of the switch 62 actuates the motor 43 and 30 through the common control connection 72 causing the belt to be actuated to move the document just referred to on to the platten 5 while feeding in a further document to the transport belt 7 for the next operation. The device is now loaded and when the photocopy machine is energized and the illuminating means 74 are actuated the photocell 50 through a switching control 76 carries out the same action as is initiated by the switch 60 to copy the document and move it out to the receiving tray 3 and feed a further document on to the platten 5 with another fed to the nip 5 of the trans¬ port belt 7. If multicopying is required, the counter 66 is set to hold the belt by withholding an initiation signal from the switching control 68 until the photocopy machine illumination means 74 have completed the required number of scans and thus copies, after which the next action is initiated through the switching con- trol 68 to again bring the belt 7 into actuation.

Claims: THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1. A document feed device comprising a frame supporting a feed tray and a receiving tray adapted to hold documents being copied, and having a transparent platten at an exposure station and means to guide a document from the feed tray to the exposure station and from the exposure station to the receiving tray, including means to synchronize the movement of the document with a photocopy machine, characterized by: a first roller and a second roller rotationally support¬ ed on a frame at a first and the other at a second end of a transparent platten supported in a window in the said frame, a transport belt passing around the said roller positioned to extend over the back of the said platten to form between the said belt and the said platten a document guide channel, said transport belt having a higher friction coefficient than the said platten whereby to move the said document over the said platten when the said transport belt is driven for- wardly, document pick-up means adjacent the discharge end of the said feed tray arranged to feed the lead end of a document to the said transport belt, secondary document transport means rotationally supported on the said frame adjacent..the receiving end of the said document receiving tray to feed a document from the said document guide channel to the said document receiv¬ ing tray, register pins projectable into the said guide channel adjacent the said second end of the said platten, drive means including an actuating switch for the said document pick-up means and for the said secondary feed means, clutch actuated drive means for the said trans¬ port belt, and light-sensitive means at the said platten to initiate drive to the said transport belt when an exposure light of the said photocopy is energized, excepting when making added multicopies. _ ' . Y ' 2. A document feed device according to Claim 1 characterized by a first guide extending from the said first end of the said platten to adjacent the said document feed tray and extending part way around the said transport belt means of the said first roller to guide a document into the said document guide channel, and a second guide extending from the said second end portion of the said platten to adjacent the said secondary document transport means and extending part way around the said transport belt means at the said second roller to guide a document from the•said docu¬ ment guide channel to the said secondary document transport means. 3. A document feed device according to Claim 1 or 2 characterized in that the said document pick-up means comprise a strip having on it a sticky surface which is more cohesive than adhesive, means to project the said strip against a document held in the said feed tray, and means to dislodge the said document from the said strip to cause it to fall endwise to the said transport belt. 4. A document feed device according to Claim 3 characterized in that the means to project the said strip against a document comprise means to urge the said strip toward the said document feed tray, and means to draw the said strip into a housing after it has been urged against a document in the said feed tray whereby to release the document from the said strip by pressure of the document against the said housing. 5. A document feed device according to Claim 3 - characterized in that the means to project the said strip against a document comprise a pinion which is toothed around part of its periphery, a rack connected with the said strip and positioned to engage the said pinion, means to drive the said pinion to move the said rack outwardly from the said feed tray, and spring means connected to urge the said rack to move the said strip on to a document in the said feed tray when the untoothed portion of the said pinion registers with the said rack. 6. A document feed device according to Claim 3 characterized in that the said drive means for the said document pick-up means comprise an electric motor coupled to drive a segmented pinion through one revo- lution for each pick-up action, and by a rack engaging the said pinion and coupled to the strip, said direction of rotation of the said pinion being such that the said rack withdraws the strip from the said document feed tray, and by spring means to urge the said rack and strip toward the said tray when the said pinion has an untoothed segment register with the said rack. 7. A document feed device according to Claim 1 or 2 characterized in that the drive means for the said secondary transport means comprise a motor connected by a drive belt to the said secondary transport means, and by a further drive belt which transmits drive to the said clutch which drives the said transport belt, where¬ by the said secondary transport means are driven con¬ stantly by the said motor and the said transport belt is driven intermittently by the said motor. 8. A document f ed device according to Claim 7 characterized in that the said secondary transport means comprise a roller in the path of a document fed from the said transport belt, and a brush positioned to press the said document to the said roller. 9. A document feed device according to Claim 1 or 2 characterized .in that the said transport belt is formed in side-by-side spaced-apart sections through the spaces between which the said register pins pro- ject and the said light-sensitive means are actuated. 10. A document feed device according to any pre¬ ceding claim characterized in that the light-sensitive means connect through a relay to the said clutch means, whereby when illumination from an adjacent photocopy machine energizes the said light-sensitive means the said clutch is -engaged to actuate the said transport belt to move a document outward from the said guide channel after the document has been exposed to the illumination from the photocopy machine, and further characterized by counter means on the said document feed device arranged to hold the said clutch disengaged until a predetermined number of illuminations have occurred. 11. An automatic document feed device for hand- fed photocopy machines in which documents to be copied are fed from a feed tray to a receiving tray over a transparent platten which is arranged to register with the illuminated exposure station of the photocopier, characterized by a transport belt of higher friction coefficient than the platten arranged to draw the document over the platten, including document pick-up means to feed a document from the feed tray to the transport belt and secondary transport means to feed the document from the transport belt to the receiving tray, and including register pins and driving means for the document pick-up means and for the transport belt and for the secondary transport means, further characterized by light-sensitive means arranged to cause the transport belt to be driven through means which move the transport belt forward each time the light-sensitive means are illuminated by the illumina¬ tion from the photocopy machine excepting when effecting ulticopying when the transport belt is not driven after a document is positioned on the platten until the necessary number of copies have been made, whereby no mechanical or electrical synchronization connection is required between the document feed and the photocopy machine . c :ι • y- " .. ' ,, ._:: K

Inventors: GRACE R, TOMES D
Applicants: GRACE R, TOMES D
Application year: 1980
Main classification: B65H3
IPC codes: B65H3, B65H5, B65H7, G03B27, G03G15