CA1167874A - Facsimile sheet feeding apparatus - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE (FIG, 1) A facsimile apparatus-with a sheet feeding capability to supply sheets of documents and/or copy paper to a rotatable scanning drum 10. Rollers 22, 42 and 44 advance these sheets 26 on a sheet-by-sheet basis along the transport path 59, which includes a plurality of sensor 60, 72 and 104. The drum 10 is positioned so as to receive the sheets 26 prior to scanning and subsequently repositioned after scanning so as to permit these sheets 26 to be removed from the drum 10.

Description

~_~t~
~ 1 BACKGROUND OF TH~ INVENTION
1 This invention relates to facsimile transmitters

2 and rece~ers of the type utilized to transmit and

3 receive information-bearing signals representing the

4 dark~light variations on a document located at the transmitter and converting the information-bearing 6 signals to marks or images on a copy medium located at 7 the receiver so as to form a copy which is a reasonable 8 facsimile o~ the original document.
9 Most facsimile transmitters and receivers in commercial use at the present time are supplied with 11 document or copy medium sheets by hand. In other words, 12 an operator takes an lndividual sheet of paper, whether 13 the original document or a blank Piece oE copy meclium, 14 and places that sheet on or in the scanning means o the transm~tter or receiver, typically a drum having a 16 clamp for clamping one edge of the sheet.
17 In some commercially available facsimile 18 equipment, cassettes or magazines are utilized to store 19 into the plurality of sheets prior to feeding to the 2Q scanning means. These cassettes include separating mem-21 bers which are inserted between ad~acent pairs of sheets 22 so as to assure that each sheet will, with reliability, 23 depart the cassette or magazine at the appropriate time, 24 i.e., there will be no sticking between the sheets re-sulting in improper feeding o~ the sheets to the scanning 26 means. In other commercial facsimile equipment, roll 27 feeders are utilized for the copy medium so as to assure 28 the supply of a fresh copy medium to the scanning means 29 with substantial reliability.
As a general rule, it is difficult to sheet feed, 31 automatically or unattended, a paper of any kind with a 32 high degree of reliability. Paper feeding mechanisms 33 are almost by nature prone to paper jams which result 3~ when more than one sheet is fed along a predetermined _;

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transport path at any one time. In facsimile applica-tion, the problem of reliable sheet feeding becomes even more severe because of the common use of electro-sensitive paper in facsimile application. Electro-sensitive paper which incllldes a plurality of layers is -characterized by a writing surface ~hich is rather glossy in appearance, and for paper feeding purpose, may be considered almost sticky. Great difficulties inhere in trying to sheet feed a stack of such paper without the use of the above-discussed paper separator cassettes or magazines. Yet, a reliable sheet feeder for a stack of such paper is, in general, preferred to the roll-type feeder previously discussed because of operator con-venience.
SUMMARY OF T~E INVENTION
It is an overall object of this invention to provide a reliable sheet feeder for a facsimile appara-tus.
It is a more specific object of this invention to provide a sheet feeder for a facsimile apparatus which is capable of reliably feeding sheets from a stack of sheets in direct contact with one another without the benefit of separator members.
In accordance with the invention and in accord-ance with the foregoing and other objects, there isprovided facsimile apparatus comprising scanning means adapted to scan and improve sheet transport means. The sheet transport means includes sheet storage means adapted to receive a stack of sheets. Scuff roller means are adapted to contact the sheets in the stack and move the sheets into a transport path. At least two transport rollers are adapted to move one of the sheets into the transport path where one of the trans-port rollers is adapted to contact one of the sheets on one side of the path and another of the transport '7~'f'~

rollers is adapted to contact the sheet on the other side of the path. Means positively drive each of the :! transport rollers such that one transport roller rotates at a different peripheral speed from another transport roller so as to accelerate one sheet with respect to another sheet when two sheets are simultan-eously located between the transport rollers.
~ n a further embodiment oE the invention, the scuff roller means and one of the rollers on the one side of the path contact the same side of the sheets.
Both the one roller and the other roller, while rotating at different speeds, rotate in the same direction at the area of contact with these sheets. The one roller which contacts the same side of the sheet as the scuff roller means rotates at a greater speed than the other roller which contacts the opposite side of the sheets.
A still further embodiment of the inventioll also comprises a movable support means for supporting the stack o~ sheets in contact with the scuff roller means regardless of the number of sheets in the stack.
The movable support means comprises a plate means and elevating means contacting the plate means so as to force the plate means toward the scuff roller means.
rrhe elevator means includes an arm mounted for pivotal motion about a pivot point with a portion of the arm - contacting the support plate and spring bias means maintaining a portion of the arm in contact with the support plate.
A still further embodiment of the invention comprises a corner separator means engaging at least one corner of the uppermost sheet in the stack. rrhe corner separator means extend over the stack and along the leading edge of the uppermost sheets in the stack in at least one corner of the stack.

? 78 ~4 - 3a -BRIEF DESCRXPTION OF THE DRAWINGS
; Fig. 1 is a sectional view throu~h a facsimile transceiver apparatus representing a preferred embodi-ment of the invention, Fig. lA is a sectional view of Fig. 1 a short time later in the feeding sequence, f '7~

1 Fig. 2 is a sectional view of Fig. lA showing 2 the sheet feeding sequence a short time later;
3 Fig. 3 is a sectional view of Fig. 2 showing 4 the sheet feeding sequence a short time later;
Fig, 4 is a sectional view of Fig. 3 showing 6 the ~heet feeding sequence a short time later;
7 ~ig. S is a sectional view of the apparatus 8 shown in Fig. 4 a short time later in the sheet feeding 9 sequence;
Fig. 6 is a sectional view of a portion of the 11 apparatus shown in Figs. 1 through 4 a short time later 12 in the sheet feeding sequence, 13 ~ig. 7 is a sectional view similar to Fig. 6 a 14 short time later in the sheet eeding sequence;
Fig. 8 is an enlarged view of a portion of the 16 sheet stora~e area shown in Fig. 1 taken along line 8-8 17 of Fig. 9;
18 Fiq. 9 is a planned view of the sheet storage 19 area shown in Fig. l;
Fig. 10 is a partial sectional view of the 21 front of the sheet storage area shown in Fig. 9;
22 Fig. 11 is a plan view of the document posi-23 tioning apparatus sho~ in Figs. 1 through 4 and 6;
24 Fig. 12 is an exploded perspective~ view of the equipment incorporating the apparatus of Fig. l;
26 Fig. 13 is a block diagram of a motor control 27 circuit for controlling the feed mechanism of Figs. 1 28 through 7.

Referring to Fig. l, a preferred embodiment of 31 the invention comprises a facsimile transceiver capable 32 of transmitting and receiving information-bearing signals 33 represent~ng dark/light variations on a document. The 34 transceiver includes a sheet scanning means comprising a drum 10 juxtaposed to a scanning head 12. The drum 10 is 36 adapted to rotate about the drum axis as the head 12 moves 37 in a direction parallel with the drum axis so s to scan a .

i'7~3'sJ4 1 sheet carried by the drum in a helical fashion such that 2 the sheet is saanned on a line-by-line basi~. The drum 10 3 includes a clamp 14 shown in the open position which is 4 adapted to recei~e ~he leading edge of a sheet and clamp the leading edge aga~nst the drum 10. As the drum 10 6 rotates, the sheet is wrapped around the drum 10.
7 In accordance with this invention, improved 8 sheet transport means are rovided including a sheet g storage means 16 adapted ~o store a stack of sheets in a b1n or cassette lB. In accordance with the invention, 11 means are provided to reliably feed sheets from the 12 cassette 18 along a transport path 59 to the drum 10.
13 This rel~ability in sheet feeding from the 14 cassette 18 is achieved in part by the use o a scuf roller means 22 mounted on a rotati.ng shaft 24 which is 16 adapted to engage the leadlng edge of the topmost sheet 17 26 in a stack 28 as shown in Fig. 1.
18 As shown in Fig. 11 the stack 28 is elevated 19 to a position such that the topmost sheet 26 is engaged by the roller means 22 by ~irtue of a plate 30 which, at 21 the forwardmost area is supported by a roller 32 rotat-22 ably mounted on a spring biased lever 34. Spring bias 23 is provided by a spring 36 which is attached to an arm 24 38 and a peg 40 mounted on the base 41 of the sheet storage means 16.
26 As also shown in Fig. 1, the topmost sheet 26 27 is maintained in contact with the scuff.roller 22. As 28 the scuff roller 22 rotates, the topmost sheet 26 is 29 forced forward out of the cassette 18 at an opening 40.
Rollers 42 and 44 which will now be described in detail 31 are located immediately in ront of the opening 40.
32 In accordance with this invention, the rollers 33 42 and 44 are driven so as to rotate in the same direction 34 at the sheets 26 as the upper roller 42 engages the topside of the sheets 26 and the lower roller 44 engages l the bottomside o~ the sheets. In accordance with one 2 important aspect of this invention, the rollers 42 and 44 3 are dr~ven at different speeds with the topmost roller 4 42 rotatin~ at a faster speed, i.e. angular velocity than S the lowermost roller 44. Preferably, the roller 42 is 6 driven at 2.5 to 3~66 times the velocity that the roller 7 44 is driven. In those instances where two sheets 26 are 8 inadvertently fed through the rollers 42 and 44, the ~ topmost sheet will be accelerated with respect to the lowermost sheet thereby separating the two sheets. This 11 separation is, in most instances earlier achieved by 12 utilizing corner separators 46 in the forwardmost location 13 of the stack of sheets 26 which will be described in 14 substantially more detail with reference to Figs. 8-10.
As shown in Figs. 8-10, a pair o corner sep-16 arators 46 are located in the forwardmost area of the 17 cassette 18 so as to enga~e the corners of the uppermost 18 sheets in the stack 28. As the scuE roller 22 moves 19 the topmost sheet 26 forward, the leading ed~e of the sheet 26 begins to buckle as shown in Fig. 8. Ultimately, 21 the buckling region 48 of the sheet 26 rides over the 22 corner separator 46 as depicted by ~he dotted line 50.
23 At that time, the topmost sheet 26 is ~ree to advance 24 outwardly toward the rollers 42 and 44.
~n order to properly serve the corner separating 26 function, the corner separators 46 include a forwardmost 27 vertical section 52 and an upper horizontal section 54.
28 It will be readily appreciated that the. vertical section 29 52 restrains the forward movement of the topmost sheets 26 in the stack 28 except for the topmost sheet 26 which 3~ begins ~o buckle in the area 48 as shown in Fig. 8. As 32 the scuff roller 22 continues to drive the topmost sheet 33 28, the buckling region 48 will finally clear the section 34 54. However, under some circumstances, the topmost sheet 26 as well as the sheet beneath may ride over the corner 1 separator 46. This of course will result in the 2 feeding of two sheets by the scuff roller 22 simulta-3 neously. Howe~er the differential speeds of the rollers 4 42 and 44 will accelerate the top sheet with respect to the sheet immediately beneath so as to assure a single 6 sheet ~ed to the drum 10. As shown in Fig. 10, the 7 size of ~he sheets 26 and the stack 28 are restrained 8 by vertical guides 56. The guides 56 also serve to g support the corner separators 46.
Referring now to Fig. lA, the sheet 26 is 11 advanced along a downwardly inclined slide 58 forming a 12 path 59 by the movement o~ the rollers 42 and 44. The 13 individual sheets 26 are transported down the incline 58 14 under the force provided by the rollers 42 and 44 until such time as the feeding is interrupted so as to prelo~ate 16 the sheets 26 ;~n the position shown in Fig. 2 short of 17 the drum 10. Th~s prelocatin~ of the sheets is necessary 18 in order to maintain the individual sheets in a state of 19 readiness 90 as to allow feeding to the dr~ 10 in a very short period alloted by the CCITT Standards, i.e., 3 21 seconds.
22 In order to interrupt the feeding of the sheets 23 26, a sensor 60 is provided in opticàl communication with 24 the sheet 26 through the guide 58. For this purpose, a small opening 62 in the guide 58 is provided. Upon 26 detection by the sensor 60, the rotation of the rollers 27 42 and 44 is interrupted and the rollers 42 and 44 are 28 separated to allow the paper to arrlve in squaring itself 29 up. The rollers 42 and 44 return to a state of engagement with the sheet 26 as shown in Fig. 2 when a signal is 31 received ;ndicating that the apparatus is ready to 32 received a facsimile transmission. Rotation of the 33 rollers ~2 and 44 is resumed and the sheet is advanced 34 down the inclined guide 58 to the position shown in Fig. 3. However, it will be appreciated that the sheet .
. -~ ~t;'4'7~

1 26 will be fed to the position shown in Fig. 2 at a time 2 when the drum 10 and the clamp 14 is not prepared to 3 receive the sheet 26. For this reason, the drum 10 is 4 depicted as rota~ing in Fig. 2, and the clamp 14 is closed. rt will also be appreciated that the feeding of 6 the sheet 26 to the position shown in Fig. 2 may occur 7 during the removal of sheet from the drum 10 which will ~ be depicted in more detail in Fig. 7.
9 In Fig. 3, the sheet 26 has been advanced along the inclined guide 58 by the rollers 42 and 44 11 to the point that the sheet 26 is engaged by a forward 12 sheet feed mechanism including a roller 64 which moves the 13 sheet 26 longitudinally along the path established by 14 the guide 26 and laterally with respect to that path.
This longitudinal and lateral motion provided by the 16 roller 64 is achieved by mounting the roller 64 on an 17 axis which forms an angle with the longitudinal path of 18 the sheets 26 of less than 90 as shown in Fi~. 11.
19 Preferably, the angle as shown in Fig. 11 lies in the range of 55 to 75 with approximately 72 being 21 preferred. In Fig. 11, the longitudinal path is 22 depicted by a line 66 and the axis of rotation for the 23 roller 64 wh~ch coincides with a shaft 68 illustrated 24 in Fig. 3 is depicted by a line 70.
As shown in Fig. 3, the rollers 42 and 44 26 located rearwardly of the roller 64 are disengaged from 27 the sheet 26, Furthermore, the elevating plate 30 28 has been lowered by lowering the roller 32 such that 29 the topmost sheet 26 and the stack 28 is not in contact with the roller 22. This prevents any further feeding 31 of sheets 26 and the stack 28 and also permits a sheet 32 26 in contact w~th the roller 64 to be moved laterally 33 without restriction by the previous engaged rollers 42 34 and 44~ This disengagement of the roller 42 and 44 and the lowering of the plate 30 is accomplished by the 36 sensing of the forwardmost portion of the sheet 26 by 1 a sensor 72 in an opening 73 located immediately adjacent 2 the rollar 64 as depicted by a dotted line 78. ~hen the 3 forwardmost portion of the sheet 26 is detected by the 4 sensor 72, this disengagement of the rollers 42 and 44

5 and the lowering of the plate 30 is accomplished. At

6 this point in time, movement o the sheet 26 is controlled

7 solely by the roller 64 in conjunction with a leaf spring

8 7~ mounted on a guide member 71 carrying a contact point

9 76 which assures good frictional engagement of the sheet

10 26 by the roller 64 which passes along a path between the

11 contact 76 and the roller 64 as shown in Fig. 3. The

12 sensor 72 also is effective to actuate a roller 64 as

13 depicted by the dotted line 78 in Fig. 11.

14 As also shown in Fig. 11, the transport path

15 includes a longitudinal guide 79 extending alony the

16 longitudinal path dep~cted by the line 66. When the

17 roller 64 engages the sheet, ~he sheet is driven toward

18 the longltudinal guide 79 so as to assure that the sheet

19 is properly la~erally positioned with respect to the

20 drum 10 and the clamp 14 of the drum as shown in Fig. 11.

21 Another sheet feed path 80 merges with the path

22 59 from the cassette 18 previously discussed so as to

23 permit the sheets fed by both paths 59 and 80 to be

24 engaged and laterally positioned by the sheet positioning

25 roller 64. In this regard, re~erence is made to Fig. 1

26 wherein a path 80 is provided by an inclined ~uide 82

27 for hand feeding of single sheets to the roller 64. In

28 this regard, it will be appreciated that the hand feeding

29 relies upon gravity to move the sheets along the guide 82

30 in the direction indicated by the sheet transport arrow

31 80 Once the sheets moving along the path 80 as well

32 as the sheet moving from the cassette 18 along the path

33 S9 are engaged by the roller 64, the sheets remain under

34 the control of that roller to laterally position the

35 sheets against the guide 78 shown in Fig. 11 while moving

36 the sheets ~orward to the drum 10.

,, l A gate 84 is located downstream of the roller 2 64 as shown in Figs. 1-3. The gate 84 as shown in 3 Figs. l and 6 is adapted to close so as to hold back 4 sheets which are fed toward the drum lO until the proper S time for ~eeding the sheets to the drum 10. Note the 6 sheet shown in phantom against the gate 84 in Fig. l.
7 The gate 84 is principally used in conjunction with 8 the single-sheet feed path 80 for the following purpose.
- 9 Where it is desirable to have sheets 26 ready to be ed to the drum 10 just as soon as the drum lO is ready to ll receive the next sheet 2 the gate may be moved to the 12 closed position as shown in Figs. 6 and 7 so as to 13 permit an operator to feed a sheet along the single-sheet 1~ feed path 80 in advance of the time in which the drum 10 is ready to receive the sheet, i.e , while the sheet on 16 the drum ~s still being scanned. This assures that the 17 sheet is ready to be placed on the drum lO just as soon 18 as the clamp 14 is in the position shown in ~i~s. 1-3.
19 Of course, by virtue of the canted mounting of the roller 64, sheets which are advanced to the closed gate 84 are 21 properly, laterally positioned with respect to the guide 22 7g-23 As shown in Fig. ll, the gate 84 preferably 24 extends along the entire width of each sheet 26. As shown in Fig. l, the gate includes an "L" shaped struc-26 ture having a stop surface 36 and a connective arm 88.
27 The arm 88 is free to pivot about a point 90 in response 28 to the actuation of a solenoid 92. The solenoid 92 is 29 mounted on a supporting surface 94 which deines yet another feed path which will be described subsequently.
31 Then the solenoid 92 is retracted as shown in Figs. 2-4, 32 the stop surface 86 of the gate 84 is open. When the 33 solenoid 92 is in the extended position, the gate 84 34 rotates about the pivot point 90 so as to place the stop - 35 surface 86 in the closed position extending through an 36 opening 93 in the guide 58.

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1 From the foregoing, it will be understood that 2 a sheet 26 as shown in Fig. 6 is fed to the gate 84.
3 While the sheet 26 is against the gate 84, another sheet 4 26 located on the drum 10 as shown in Fig. 6 is being scanned by the rotational motion of the drum 10 and the 6 movement of the scanning head 12. Once the sheet 26 7 located on the drum 10 is removed from the drum as 8 depicted in Fig. 7, the drum 10 is free to rotate to a 9 position such that the open clamp 14 is aligned with the feed path adjacent the gate 84. Only at this time will 11 the gate 84 be moved to the open position so as to allow 12 the sheet 26 under the control of the roller 64 to advance 13 into the clamp 14. Once the sheet 26 is on the drum 10 14 the gate 84 may again be closed and await receipt of the next sheet 26 ed to the gate 84 by the operator with 16 the assistance of the roller 6~.
17 Referring again to Fig. 1, another sheet feed 18 path 95 is provided from yet another cassette 96. The 19 cassette 96 is inclined and located above the single sheet feed path 80 and the multisheet storage area 16.
21 The cassette 96 also includes a multisheet capacity.
22 In order to individually feed the sheets 98 from the 23 cassette 96, a scuff roller 100 engages the sheets 98 24 near the leading edge. The uppermost sheet 98 is held ~n contact with the scuff roller 100 by means of a leaf 26 spring ~02 mounted on a plate 103 which forces a plate 27 104 upwardly toward a scuff roller 100. The sheets from 28 a cassette 96 are driven downwardly under the influence 29 of the roller 100 along the support member 94 toward the drum 10.
31 Itwill,therefore,be appreciated that there are 32 three separate sheet ~eed paths to the drum 10 although 33 the last-ment~oned feed path does not pass the roller 64.
34 Accordingly, the sheets 98 are not subject to the lateral positioning, and it is, therefore, important that the ;

1 cassette 96 be properly constructed so as to reliably 2 permi-t the removal of the sheets 98 from the cassette 96 3 in the appropriate lateral position. This may be 4 accomplished by utilizing, for example, plastic separator sheets between the sheets 98 having openings through the 6 separator sheets so as to permit engagement o~ a roller lO0 7 with each individual sheet 98 in accordance with prior 8 art practices. Of course, it will be appreciated that 9 the plastic separator sheets will provide low resistance to movement of the sheets 98 from the cassette 96.
ll Another sensor 104 located adjacent an opening 12 106 is shown in Figs. 1-4. The sensor 104 and as~;ociated 13 circuitry detects the variable length o sheets moving 14 along transport paths 95 and 80 which merge in advance of the sensor 104.
16 Therefore, in order to remove the sheet~ From 17 the clamp 14, it becomes necessary to engage the sheets 18 at or near the trailing edge of the sheet. This requires l9 the position of the trailing edge o the sheet to be known so that the drum 10 can be rotated to a position such 21 that the sheet remo~ing means in the form a roller 108 22 as shown in Figs. 1-4, 6 & 7 is appropriately positioned 23 with respect to the trailing edge of the sheet 26. More 24 particulary, as shown in Fig. 7, the drum ~0 must be rotated to a position such that the trailing edge is 26 juxtaposed to the roller 108. Except for rotational 27 motion indicated by an arrow llO and as provided by a 28 motor driven pulley 113 and a belt 115 as shown in 29 Fig. 1 and slight motton toward the drum 10, this roller 108 is stationary, i.e. the roller 110 does not 31 move peripherally around the drum lO.
32 As shown in Fig. 6, the sheet 26 is being 33 scanned by the head 12 as the drum 10 rotates. At the 34 concluslon o~ scanning, the drum is automatically rotated to a rest position such that the trailing edge lll is 36 located adjacent the roller 108 as shown in Fig. 7.

1 The roller 108 is then moved into a position of engage-2 ment with the sheet 26 and rotation begins as depicted 3 by the arrow 110 so as to strip the sheet 26 from the 4 drum 10. Throughout this period of time, the gate 84 is shown as closed so as to prevent the feeding of sheets 6 onto the drum 10 since the drum 10 i~; not in a position 7 to receive sheets due to the nonalignment of the clamp 8 14 w~th the various transport feed paths 59, 80 and 95.
9 With reference to Fig. 12, the separable nature of the feed mechanism shown in Figs. 1 through 7 ~orm a base 11 unit 400 in which the drum 10 and the head 12 are mounted.
12 It will be appreciated that the sheet feeding 13 mechanism is entirely separable from the base unit 400 14 which is adapted to receive pins 402 of the sheet eeding mechanism in tracks 404. ~n interlock mechanism including 16 a can 406 is adapted to interact with a switch mounted 17 adjacent the trac]s gO4 but not~ shown in Fig. 12.
18 The separable nature of the cassette 18 and the 19 cassette 96 from ~he sheet feedin~ mechanism is also illustrated in Fi~. 12. A sheet 408 adapted to be fed 21 on a single sheet-by-sheet basis is also shown in Fig. 12.
22 The cassette 96 is shown as clearly comprising 23 separator sheets 410 havi~ngelongated openings 412 adapted 24 to receive the rollers 100 which aremountedon a shaft 414- A motor 416 drives the shaft 414 by a helt 418.
26 The cassette 96 may be readily inssrted into the sheet 27 feeding mechanism along-a guide surface 420. Similarly, 28 the cassete 18 may be loaded into the feed mechanism 29 along a guide means 42 only partially shown.
Prior to`sliding the pins 402 into the tracks 31 404 of the base 400, the feed mechanism is interconnected 2 with the base unit by means of a plug 424 which is 33 received by a jack 426. The base unit 400 also includes 34 a head drive mechanism comprising a belt 428. The belt 428 is moved by means of a head motor not shown so as to 36 produce a linear scanning motion along the drum 10. After ,", "-J~

1 the head 12 has scanned the drum 10 and the sheet on 2 the drum 10 is stripped in accordance with this inven-3 tion, the sheet exits the base unit 400 through an 4 elongated opening 430.
Reference will now be made to Fig. 13 for a 6 discussion of the control o the roller 22 and the 7 roller 42 and 44 in response to the sensing of a sheet 8 by the sensor 60. A motor 140 drives the roller 22 9 and the roller 42 and 44 in response to the output of a motor drive circuit 142 which is under the control of 11 a flip~flop 144. The input to the flip-flop 144 is 12 connected to the output of a "D" type flip-flop 146.
13~ The flip-flop 144 ~s reset by a latch 148 which also 14 serves as the data input to the flip-flop 146. The "D"
lS type flip-flop 146 is strobed by the sensor 60.
16 In response to an input signal from an input 17 circuit 150, the latch 148 goes high and ~he fli.p-flop 18 144 is reset so as to enable the motor drive circuit 1~2 19 which in turn results in the rotation o~ the rollers 22, 42 and 44. The motor 140 continues to run until such 21 time as the sensor 60 generates a positive-going pu}se 22 which triggers the ~D~ type flip-~lop 146 to set the 23 flip-flop 144 and disables the motor drive 142 the same 24 time of setting the latch 148. At this time, the sheet 26 as shown in Fig. 2 remains stationary.
26 When the input circuit 150 generates another 27 signal such as that from a remote transmitter indicating 28 that it is time to reset the transport of the sheet 26, 23 the latch 148 is again set resulting in the resetting of the fiip-flop 144. This enables the motor drive 142 31 which energizes the motor 144 and rotates the rollers 32 2~, 42 and 44. This advances the shee~ 26 clear of the 33 sensor 60 so as to produce a negative-going pulse.
34 However, the "D" type flip-flop 146 is not responsive to the negative-going pulse.
36 It will be appreciated that the control .

1 circuit shown in Figs. 13 may be modified. One modi-2 fication would be the use of a microprocessor suitably 3 programmed in place of discrete logic circuitry.
4 Although a particular embodiment of the invention has been shown and described it will be 6 appreciated that various modifications may be made 7 which will occur to those o~ ordinary skill in the art 8 without departing from the true spirit and scope of 9 the invention.

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Claims (11)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Facsimile apparatus comprising scanning means adapted to scan a sheet and improved sheet transport means comprising:
sheet storage means adapted to receive a stack of sheets:
scuff roller means adapted to contact said sheets in said stacks and move said sheets into a transport path;
at least two transport rollers adapted to move one of said sheets into said transport path, one of said transport rollers adapted to contact one of said sheets on one side of said path and another of said transport rollers adapted to contact said one of said sheets on another side of said path; and means for positively driving each transport roller such that said one transport roller rotates at a different peripheral speed from said another trans-port roller so as to accelerate one sheet with respect to another sheet when two sheets are simultaneously located between said transport rollers.

2. The facsimile apparatus of claim 1 wherein said scuff roller means and said one of said transport rollers-contact the same side of said sheets.

3. The facsimile apparatus of claim 2 wherein said one of said transport rollers rotates at a greater speed than the other of said transport rollers.

4. The facsimile apparatus of claim 1 further comprising movable support means for maintaining a sheet in said stack in contact with said scuff roller means.

5. The facsimile apparatus of claim 4 wherein said support means comprises a plate means in contact with the lowermost sheet in said stack.

6. The facsimile apparatus of claim 5 further comprising elevator means contacting said plate means and forcing said plate means upwardly.

7. The facsimile apparatus of claim 6 wherein said elevator means comprises a pivotally mounted arm having a portion contacting said plate and bias means for pivoting said arm such that said portion contacts said plate.

8. The facsimile apparatus of claim 7 wherein said transport rollers move in the same direction at the area of contact with said sheet.

9. The facsimile apparatus of claim 8 wherein said one of said transport rollers rotates at a greater speed than the other of said transport rollers.

10. The facsimile apparatus of claim 1 further comprising corner separator means engaging at least one corner of the uppermost sheet in said stack.

11. The facsimile apparatus of claim 10 wherein said corner separator means extends over said stack and along the leading edge of the uppermost sheets in said stack in said at least one corner.