Note: Descriptions are shown in the official language in which they were submitted.
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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
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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.
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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,
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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.
29 DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
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
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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
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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
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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
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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.
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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.
.
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
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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.
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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
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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
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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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