JPS6039610B2 - paper feeding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a sheet feeding device for forming a convex bend in paper such as copy paper used in a copying machine.

Hereinafter, the term "sheet" refers to a sheet-like medium such as transparent or opaque copying paper that is normally used in a copying machine. BACKGROUND ART In the field of sheet feeding technology, it is known that many benefits can be obtained by convexly bending the sheet during sheet feeding.

Apparatus for convexly bending sheets has been utilized to improve the process of separating sheets from a stack of sheets. A typical example using such a sheet bending device is a reverse bending sheet supply device. In this apparatus, to form a bend in the sheet, the sheet at the top of the stack is first fed rearwardly against a stop member to separate it from the stack, and then forwardly along a suitable sheet feed path. Another purpose of bending the sheet in a sheet feeding device is to eliminate distortion of the sheet relative to the sheet path that may occur during the initial feeding process. Again, the sheet is first bent against the stop member, as previously described. The sheet is then further bent to remove the distortion. In this case, the sheets are fed from the stack against the alignment gate and bent in a forward direction to remove sheet distortion. In particular, when bending is performed to remove sheet distortion during sheet feeding, the height of the bending must be controlled in order to consistently remove sheet distortion.

Various devices have been used to control the bending height. One method is to fix the sheet feeding time in order to control the bending height. Although this method is suitable for the purpose of removing sheet distortion, it leaves room for further improvement. The method of fixing the feed time to form a bend takes into account that the slippage between the sheet feeder and the sheet and the position of the front green of the sheet are different at the beginning of each feed cycle. do not have. The prior art also employs other methods of controlling bend height within sheet feeding devices.

That is, a device has been disclosed that controls the bending height by electrically sensing the bending height using a photoelectric detector, a bar switch, or the like. After the appropriate bend height is sensed, the sheet is advanced in a known manner. The use of optical sensors or lever-type switches to sense bend height has the disadvantage that it is difficult to accurately position the sensor during the sheet feed path.

It has also been found that, when sheets are of different types, bends are not necessarily formed at the same point in the sheet feeding path. An obvious example of this would be when a label sheet is sent to an image forming device such as a copying machine. Label sheets typically consist of a flexible sheet with a plurality of labels adhered to one side of the sheet. When bending this type of sheet, the parts of the sheet between the labels have greater flexibility than other parts of the sheet, so that in this case the label upstream or downstream of one bend Bends may also be formed in the intervening sheets. SUMMARY OF THE INVENTION In accordance with the present invention, a sheet feeding apparatus for forming bends in a sheet is provided.

Sensing equipment is provided to sense the position of the edge of the sheet. A timing device is provided and coupled to the feed device responsive to the sensing device to measure a reference time interval from the time of edge sensing. The timing device includes a device for stopping the feeding device at the expiration of the reference time interval. The reference time corner is selected to be long enough for the feeding device to feed the sheet relative to the stop member to form a bend. Preferably, the timing device is adjustable so that the reference time interval can be varied.

According to the present invention, it is also possible to provide a device for detecting clogging or jamming of sheets in the sheet feeding device. The jam detection device is coupled to the sensing device to determine the presence or absence of a sheet at the sensing device at a predetermined time. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sheet feeding device for forming a convex bend in a sheet in order to eliminate distortion of the sheet and controlling the height of the bend to be constant.

Another object of the present invention is to provide a sheet feeding device that allows the height of the bends formed to be precisely controlled.

Yet another object of the present invention is to provide a sheet feeding device in which the height of the bend formed is electronically controlled.

Other objects will become apparent from the following description and drawings.

The invention will now be described in detail with reference to embodiments shown in the accompanying drawings.

For example, various improvements have been made in feeding devices used in compact electrophotographic copying machines to effectively utilize separators.

In compact copiers, the components of the sheet feeding device,
The alignment mechanism and imaging device are all short and located in the sheet feed path. Therefore, the sheet being fed by the registration rolls may still be partially retained within the separator nip. Since the alignment roll sends the sheet to the edge forming member, the valley roller is aligned with the trailing edge of the sheet. It is necessary not to disturb the smooth movement of the roll, and furthermore it is necessary that its action does not cause a distribution of forces that would cause waving of the sheet, especially in the transverse direction. This sheet corrugation results in the appearance of finger-like transfer defects in the copied image, resulting in copy quality defects. Most electrophotographic reproduction machines use a center separator, ie, a separator that feeds sheets from the transverse center of the stack.

When using such a centered sheet feeding system, it is required that the document being copied be centered on the perspective platen. In newer copiers, edge registration devices are used for documents; these devices use a sheet feeding device that registers the stack against one side of the sheet feeding device. In this type of sheet feeding system, the sheet separators may be off-center with respect to the stack due to the various paper sizes being fed. When a sheet separator is used with off-center sheet feeding, there is a tendency for the sheets being fed to wrinkle or warp.

This distortion can be largely eliminated by appropriately guiding the green portion of the sheet during sheet feeding. If any distortion still remains, that distortion can then be removed by inserting the sheet into the appropriate alignment gate to form a forward bend. The sheet feeding apparatus detailed herein is constructed for use in a steel-tight environment.
This device is highly reliable, with 4.0% less sheet clogging, jamming, and misfeeding. The various improvements detailed below are presented in the overall sheet feeding apparatus that is the preferred embodiment of the present invention. However, these improvements have wide application in general in the field of sheet feeding technology and are therefore not necessarily limited to the particular type of sheet feeding apparatus that will now be described. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1-3, the components of a sheet feeding apparatus 10 according to the present invention are shown.

The device is equipped with a sheet support drawer 11 for supporting the stack. Although an upper sheet feeder is shown in these figures, the various components of the invention may be applied to the lower sheet feeder as well as the upper sheet feeder. Frictional engagement separator 12 is supported in a pivot 13 that pivots about axis D of shaft 14 .

The driving source force for the separator 12 is the belt feeding device 17
is provided by a shaft 15 connected at one end to a rear pulley 16 of. The end of this shaft 15 is attached to a timing belt pulley 18. The second timing belt pulley 19 is mounted to rotate around the shaft 14, and a timing belt 20 connects both pulleys. The drive gear 47 is attached to the pulley 19 and is supported on the shaft 14 . The drive system 22 engages with the gear 21 and drives the feed belt 17. Separator 12 is provided with a pivotable alignment gate 80 and alignment pinch rollers 24 which first bend the sheets in a forward direction to remove any residual distortion and then bend the sheets in a timed relationship. Transfer to appropriate imaging member.

A motor M is provided within the drive system 22 to drive the alignment loft 24 by means of a drive chain 25, which chain is connected to the shaft 26 of the lower alignment roller 27. Upper registration roller 28 is free-floating on shaft 29 relative to lower registration roller 27. The arrangement of cam 30 and cam follower 31 is used to pivot registration gate 80 in and out of the sheet prevention position in the sheet path. Illustrated sheet feeding device 10
is configured for use in a sheet green section laminated copier, such that the stack is connected to the first sheet side guide member (
side. guide) 32.

A second adjustable side guide 33 is provided to engage the opposite side of the stack. The restraints 34 are provided to restrain the edges of the sheets of the stack so that the traverse of the sheets can be effectively guided as the sheets are fed through the separator 12. As mentioned earlier, depending on the width of the sheet being fed, the separator may or may not be centered on the sheet, so proper edge guidance is required to minimize distortion caused by the sheet feeding device. be. A cross-forming section, such as the electrophotographic drum shown in FIG. 14, typically includes an alignment roller 24 in the sheet feed path. The imaging member is not shown in FIG. After the transfer operation, a transport device 35, such as a vacuum transport device, is used to transport the sheet away from the imaging member. The stationary cam 36 and the super-moving follower 37 cause the separator 12 to become stacked when the drawer 11 is pulled out to the extended position for loading and unloading sheets or for clearing possible paper jams or misfeeds. Rotate the separator 12 so that it does not engage with the separator 12.

Referring to FIG. 2, the drawer 11 is in its extended position
The released state is shown.

In the extension & layer, the drawer 11 has been extended outwardly from its operating position a sufficient distance to handle the stack supported thereon. In addition, the separator 12 is also extended to an extended position to allow for handling of sheets stuck in its recesses. The separator 12 is pivoted upwardly by the action of the follower 37 and cam 36 described above to a position where it does not contact the stack. Separator 12
is attached to the upper bar 39 of the rotating frame 13 as a device including a feeding belt 17 and an engagement pad 38 for engaging with the sheets and feeding the sheets one by one. Side plate 4
0 and 41 are adapted to pivot around the center of the shaft 14. The side plate 41 is suitably journalled for rotation about the axis 14, and the side plate 40 is attached to the drawer 1 in a manner not shown.
It is pinned to the frame of 1 so that it can rotate freely. A loading plate (baffle) 42 is provided for sheet loading which is arranged to be pivoted into the operating position when the separator 12 is cammed out of contact with the stack.

The loading baffle 42 is supported by pivotable side plates 40 and 41, and in the illustrated embodiment constitutes an integral part of the lower paper guide member 43. The provision of a pivotable loading baffle 42 allows the front green of the stack to be aligned with the baffle 42 on the drawer 11. The stack is connected to the loading baffle 4 as well as to the fixed side guide 32.
2. Adjustable side guide 33 is then pressed into engagement with the free side of the stack. In this way, there is no need to provide supports for the trailing edge of the stack, yet a means is provided for accurate alignment of the front green of the stack with respect to the position of the separator 12. The pivoting movement of the loading baffle 42 is shown in FIGS. 3A and 3B.

In FIG. 3A, the separator 12 shown in solid line is the cam 3
6 and follower 37, it is pivoted to the loading position. In this position, the baffle 42 has sufficient height relative to the support plate 44 so that the maximum height stack P' to be used can be placed relative to the baffle. An engagement pad 38 that engages the belt or sheet of separator 12 is located on the rear side of baffle 42 and extends adjacent to the stack through a groove 45 in the baffle.
The illustrated baffle extends along the length of the front green of the stack. The full range of movement of separator 12 and baffle 42 is shown in FIG. 3A, while FIG. 3B shows the separator and baffle in operation for intermediate stack heights. In the device shown, baffle 4
The lower paper guide member 43 is formed as an integral part of 2.
The shape will be described in detail later. According to FIG. 3A, the separator 12 is pivoted over the entire height of the stack. In the illustrated device, this range is approximately 130 degrees from the horizontal plane. Next, Figures 2, 4, and 5
Referring to the figure, the separator 12 is attached to the seat support drawer 1.
1 into the extended position, a drive connection 46 is required to drive the feed belt.

In the illustrated embodiment, the drive connection 46 is coupled to a pair of gears 47
and 48. These gears are for bow length 1
1 in its operating position, i.e., the sheet feeding position, and not when the drawer is in its extended position, i.e., the reloading position. Gear 48 is attached to shaft 26, and gear 47 is journaled to shaft 14. Gear 47 is coupled to pulley 19 via an electrically actuated clutch 50. The pulley 19 is connected to the shaft 1 by the timing belt 20'.
5, and the shaft 15 is connected to the rear flap of the feed belt 17. −
1" 16. The seat support drawer 11 is adapted to slide on a rail 51 between an operating position and an extended position, as shown in FIG.

The adjustable dowel screw 52 at the end of the rail 51 is
This is means for adjusting the position and displacement of the separator 12 with respect to the alignment roller 24 in the sheet feeding path. As shown in FIGS. 5A and 5B, a single switch actuator and switch 53 are provided to detect both the no-paper condition and the engaged condition of drive connection gears 47 and 48. ing.

Referring to FIG. 5A, the gear 4 of the drive connection device is in a separated state corresponding to the extended position of the seat drawer 11.
7 and 48 are shown. In this position, the microswitch 54 and the cam 59 are not in contact and the microswitch 54 is not activated. This means that even if the stack is placed on a support tray and the switch actuator 55 is pushed down as shown by the dotted line, the microswitch 54 and the cam 59 do not come into contact with each other, so the switch 54
is not activated. As shown in FIG. 5B, when the support tray is pushed into the copying machine into the operating position for paper feeding, gears 47 and 48 are engaged as shown, and switch actuator 5
The cam 59 of No. 5 engages with the detection microswitch 54. As shown in FIG. 5B, when there is no stack on the support plate, the lever arm 56 of the actuator 55 projects onto the support plate through the groove 57 in the support plate, so that the microswitch 54 and the cam 227 do not come into contact. First, switch 54 is not activated. When the stack is placed on the support tray, arm 56 is pushed up by the stack as shown in dotted lines, activating switch 54. As a result,
A signal is generated indicating that paper is present and that the drive connection is engaged. That is, activation of switch 54 requires both engagement of drive connection device 46 and the presence of paper. To achieve such simultaneous operation, a lever arm 56 actuating against the switch 54 is mounted at the bottom of the support pan, while the switch itself is mounted on a fixed frame (not shown) over which the support pan slides. ). The lever arm is pinned at one end to the lower part of the support pan, and the other end is arranged so that it projects through the groove 57 in the support pan when nothing is stacked on the support pan. At one end of the lever arm adjacent to the pivot point there is a switch 5 when the support pan is in the operating position.
A cam portion 59 is provided for engaging 4. This cam portion pivots relative to the switch activation button to open and close the switch. When the support plate is withdrawn to its extended position, the cam portion 59 of the lever arm 56 is withdrawn to a position out of engagement with the switch 54. lever·
The arm 56 is adjustably mounted to the lower part of the support pan by screws 58 so that the cam portion 59 engages the switch and actuates the switch 54 only when the drive connection is in proper engagement. can be positioned at In this manner, the switch operates to sense both drive mechanism engagement and the no-paper condition. As mentioned above, the preferred sheet separator for use in the present invention uses sheet organizing throats that sandwich the sheets to separate the top sheet from the stack. Both the feed belt 17 and the engagement pad 38 travel together with the drawer 11 to the extended position;
The belt and engagement pad are not separated. Therefore, when changing the stack, it is possible that one or more sheets may become wedged between the feed belt and the engagement pad. One of the main reasons why it is desirable that the sheet separator 12, like the drawer 11, be extended from the copier is to allow the user to easily access the sandwiched sheets as described above. It is. The pinching force between engagement pad 38 and feed belt 17 must be at the desired level to separate the sheet from the stack. This pinching force creates a difficult problem when extracting a sheet that is stuck in the nip, for example, to replace the sheet or clear a jam. Therefore, when attempting to remove a sheet in the opposite direction to the sheet feeding direction, the pinching force between the engagement pad 38 and the feed belt 17 is automatically reduced, and when the sheet is fed in the sheet feeding direction, the pinching force is reduced. A device is used that automatically increases the amount of water to the desired level.

Such a function is provided by the engagement pad 3 shown in FIG.
This is obtained from the toggle mechanism 601 for 8. As shown in FIG. 6, the engagement pad 38 pivots around a pin 61 that extends in the sheet feed direction, ie, across the feed belt. The engagement pad is supported by a member 62 having a groove 63, and a pin 61 is disposed in the groove so as to pivotably support the cover material 62.
The pivot point of the support member 62 is offset downstream from the center of the support member as shown. The support member 62 consists of a long first leg having an engagement pad 38 aligned with the feed belt 17, and a short second leg disposed approximately at right angles thereto. It has an L-shaped shape. The second leg of the stub has a groove 63 formed by comb-like protrusions, which protrude around the pin to provide a pivotable mounting structure. The first adjustment screw 64 is screwed into the lower paper guide section 43 of the rotating frame 13 and abuts against the first leg of the cover material 62.

This adjustment is for adjusting the range of rotational movement of the support member 62 that is allowed when the sheet is pulled in the opposite direction to the sheet feeding direction. The second adjustment screw 65 is
It is provided on one of the comb-like protrusions of the second leg of the support member. This second adjustment screw is connected to the member 62 when the sheet is fed.
In order to adjust and limit the range of movement of the guide plate 43, it cooperates with a plate 66 fixed to the lower part of the guide village 43 as shown. By arranging the pivot point of the member 62 from the center of the engagement pad in the sheet feeding direction and upstream of the vertical centerline of the member 62, the movement of the sheet during sheet feeding is controlled by moving the Miyakomura 62 toward the pin 61. , thereby increasing the deflection of the feed belt 17 at the pulley engagement and automatically increasing the pinching force between the feed belt 17 and the engagement pad 38 during sheet feeding. .

The rotation range of member 62 is determined by adjustment screw 65.
Therefore, during sheet feeding, the pad turns in the anti-Japanese direction, causing the belt to flex to a large extent, thereby providing a relatively large pinching force between the belt and the pad. When attempting to remove a sandwiched sheet, or when attempting to remove a sheet from the sandwiched portion of the separator 12, when the sheet is pulled out, the engagement pad 38 is rotated clockwise until it hits the screw 64. , the deflection of the belt 17 is reduced, thereby reducing the pinching force between the belt and the pad. In this way, separate
The pinching force can be automatically reduced when a sheet is to be pulled out from the nip section, and the pinching force can be automatically increased when a sheet is to be fed. Engagement pad 3
Such a simple toggle mechanism for 8 makes it easier to pull out the sheet sandwiched between the separator and the engagement pad compared to devices that require the user to manually pivot the engagement pad. The seat can be pulled out. - Another preferred feature of the sheet support drawer and separator arrangement according to the invention is the provision of an upper paper guide member 7 for proper guidance of sheets that may have curled edges.
The reason is that 0 is set.

A problem associated with various types of copying machines, particularly those using radiation fusing processes, is that the green portion of the copy sheet curls. If it is desired to refeed these crooked sheets to the copier in order to obtain duplex copies, i.e. copies on both sides of the sheet, it is difficult to provide reliable sheet feeding without the possibility of jamming. there were. The upper paper guide member 7 is constructed in consideration of a sheet whose green portion is bent toward the top surface when the bent sheet is fed a second time for copying on the back side thereof. Dog ears 71 are provided in the upper paper guide member 70 as shown in FIGS. 1, 2, and 7 to accommodate these curled edges and feed the sheets into the apparatus. The dog-ear shaped portion 71 of the upper paper guide section 70 is designed to maintain a gap between the upper paper guide member and the lower paper guide member 43 so that jams will not occur even if the green portion of the paper is crooked. It is gradually increasing and being pushed upwards. The illustrated upper paper guide member 70 has a plate-like shape that extends along the sheet feeding path, and has the same extent as the feeding belt 17 as a whole in the sheet feeding direction.
The guide member 7 is attached to the pivot frame 13 by known means (not shown). The upper paper guide member 7 is generally opposed to the lower paper guide section 43 for feeding the sheet over the desired sheet transport path. The upwardly extending dog ears 71 enable the feeding of sheets with curled edges. Referring to FIG. 7, after separating the sheets from the stack, the sheets are separated from the upper and lower paper guide members 70.
and 43 along the sheet feeding path defined by
The pivotable alignment gate 8 is extended and engaged with the gate 80.

The sheet continues to be fed until a relatively high forward bend is achieved as shown. The large directional bend formed generally has a height-to-length ratio of about 1 to 4, but in order to eliminate paper distortion due to paper separator feed, the ratio of the height to length of the bend should be about 1 to 4. Preferably, it has a value of 6. Paper distortion is undesirable for copying machines. This is because the distortion creates a misaligned image and can also cause sheet jams at downstream processing locations. To eliminate this distortion, the bending height of the sheet must be controlled constant. One of the problems with belt-pad friction-engage separators, where a sheet to be fed following a previously fed sheet may be stuck in the sheet organizing throat, is that the leading edge of the sheet is always It is not in a fixed position.

Therefore, given a certain amount of time for bend formation, the resulting bend depends on where the leading edge of the sheet is within the nip prior to the feed cycle, so that the bend height is It will change significantly. Detecting the actual bend height is also difficult. This is because the highest point of bending can take various positions along the sheet feeding path depending on the thickness and material of the sheet being fed. For example, labels and similar materials bend in unusual positions compared to sheets. Therefore, according to a preferred embodiment of the invention, an apparatus for obtaining a constant sheet bending height,
Therefore, sensing the front green of the sheet and then for a predetermined time,
An apparatus is provided that can bend a sheet and completely eliminate sheet distortion. To accomplish this, a leading edge sensor switch 81 is provided in the sheet feed path so that the leading edge of the sheet grips the front sensor switch 81 before gripping the registration gate 80. The illustrated switch 81
is shown in close proximity to the alignment gate, but its location may vary and could be placed near the separator if desired. The leading edge of the sheet being fed closes the switch 81, causing the timer 82 to measure the reference time during which the separator 12 continues feeding the sheet. After expiration of this reference time, the separator 12 is deenergized by the electric clutch 5. Although a lever switch 81 is shown as the front green sensor, it is clear that other types of detectors could be used, including photoelectric detectors. The lever switch is advantageous because it is unaffected when feeding transparent materials such as transparency paper. Timer 82 may have any structure. According to the present invention, it is preferable to use an electronic timer as the timer and incorporate it into the copying machine control system. FIG. 8 shows a flow diagram of a control system with an electronically timed bend height control.

The flowchart of FIG. 8 may be applied to a copier in which an optical scanning device is used to form a recorded document image on a transparent platen. The scanned optical image is then projected onto an electrophotographic drum. Details of such a process and apparatus will be described later with reference to FIG. 14. Referring to FIG. 8, when the "print" switch 90 of the copying machine is actuated, a controller 91 consisting of a logic circuit for controlling the copying machine and an optical sensor 92 are started, and a signal for preparing the optical system and for preparing the copying machine is activated. to the scan logic controller 93, respectively.

This signal energizes scan controller 93, which in turn energizes engagement clutch 50 to couple driveline 22 to frictional feed separator 12, and also energizes scan solenoid 95. This solenoid causes the optical system 96 to scan the entire predetermined path and operates the alignment device 80 which aligns the copier with respect to the image projected on the drum. When the engagement clutch 50 is energized, the sheet is fed by the separator 12 and the edge of this sheet actuates the sensor switch 81. When the sensor switch 81 is activated, a first signal A is applied to the electronic timer 104, and a selection signal is applied to the logic circuit 101 for detecting a jam in the copying machine. A master counter 102, which controls the timing of the copier logic, is coupled to a time delay logic circuit 103 which provides a time delay signal to the electronic bending control system energizer 100 so that the energizer 100 is Sensor switch 8 according to the sent sheet
This prevents the application of the energizing signal B to the timer 104 prior to the passage of 1.

This time delay circuit is long enough that the entire length of the previously fed sheet passes through the sensor switch 81 and the sensor switch is deenergized before the timer is energized, and that the newly fed sheet is sensor before the expiration of the device delay time.
It is set to a time interval that is short enough not to reach the switch. After such a time delay, the bending control system energizing signal B is generated, and when the sensing signal A from the switch 81 is present together with this signal, the electronic timer 104 is activated to measure a predetermined reference time. This reference time is the time during which the separator 2 continues to feed the sheet in order to bend the sheet against the alignment gate 80'. When the reference time expires, the timer 104 applies a de-energizing signal C to the engaging clutch 5 to switch the drive system 22 to the separator 12.
Release from. The mass counter 102 is reset to zero by a suitably timed signal G from the copier controller 91 after each copy is taken.

Master counter 102 generates signal E at the appropriate coefficient value to reset flex control system energizer 100. Optionally, master counter 102 may also send a signal to energize jam logic circuit 101;
This allows the sensor switch 81 to be interrogated at appropriate time intervals to ensure that the sheet is being advanced.

If the jam logic 101 does not receive a signal from the sensor switch indicating so, a signal is generated by the jam logic and sent to the copier stop logic 105 to stop the copier. The jam logic circuit and the stop logic circuit may have any known configuration. For example, one type of control logic for jam detection and copier shutdown is described in commonly assigned US Pat. No. 3,813,157. Referring to FIG. 9, components of the electronic timer and bend control system 110 of FIG. 8 are shown in greater detail in accordance with a preferred embodiment of the present invention.

The sensor switch 81 is comprised of a single-pole double-throw switch as shown.

A complementary output signal from this sensor switch is at terminal 1.
11 and 112, and these terminals constitute the input terminal of the noise suppression circuit 113. This suppression circuit is of a known construction including a resistor and a capacitor as shown. A D-latch circuit 114 or flip-flop type circuit is included as part of the noise suppression circuit.

The set and reset terminals of this latch circuit 114 are connected to a logic voltage source through separate lead resistances. Thus, depending on the level of switch 81, one input terminal of the latch circuit will be at a high level and the other input terminal will be at a low level. When the switch is closed and a given terminal 111 or 112 is grounded, a low level signal is generated.
In the illustrated embodiment, switch 81 is connected to terminal 112 since it is not actuated by an incoming sheet and is therefore connected to reset terminal D of latch circuit 114.
A low level signal is applied to the set terminal, and a high level signal is applied to the set terminal. In this state, the latch circuit 11
The output of 4 consists of a low level signal. When a sheet is sensed, switch 81 grounds terminal 111, so
The set terminal of latch circuit 1 14 shifts to low level,
This causes the latch circuit output to go high. The output of latch circuit 1 14 is applied to one input terminal of NAND gate 1 1 5. The other input end of gate 115 is connected to a 60Hz power supply. This NAND gate operates to output a 60 day 2 clock pulse train to a binary counter (binary ring counter) 116. Master counter and decoder 117, which includes devices 102 and 103 of FIG.

- As mentioned above, the set signal for the energizing device 100 is decoded after an appropriate delay time.
A reset signal is generated when master counter and decoder 17 decodes the desired coefficient value corresponding to the desired time interval for resetting the energizing device. D-
The output of the energizing device 100, which is a latch circuit, takes a high level when set and takes a low level when reset. This output is applied to the first input of NAND gate 1 1 8. The second input of NAND gate 1 18 is
It is received from the copier controller 91 in the figure via the terminal 119. This receive input consists of a cycle deactivation signal that goes low when the copier is operating from its standby state to its ready state and goes high when the copier reaches its ready state. The third input of the NAND gate 118 is
A cycle deactivation signal received via terminal 120 from the copier control that goes low when the copier is returning from its ready state to its standby state and goes high when the copier is in its ready state. Consists of signals.
When all inputs of NAND gate 1 18 become high level,
A level signal is generated to energize counter 16. Therefore, under the conditions described above, the counter 16
The clock pulses sent from the D gate 115 are counted. If desired, the state of the copying machine need not be taken into account, and a conventional NAND gate 118 can be used instead of the NAND gate 118 to change the output of the flip-flop type energizing device 100 from a high level to a low level that counter-energizes. An inverter of this configuration can be used.

Binary ring force counter 1 corresponding to the desired binary number
The four outputs from 16 are applied to respective inputs of NAND gate decoder 25 via switches 121-124. The lead resistor 126 is provided to each input line between the switch and the input terminal of the decoder 125, and provides a high level signal to a predetermined input terminal when the switch of each input line is open. By opening or closing switches 121-124, a desired count value within the range of the counter can be decoded to generate an output signal from decoder 125 indicating the end of the reference time. A switch connected to the line as shown can therefore adjust the reference time of timer 04 as desired. For the counter shown,
A time interval count value of 0 to 15 may be decoded, which corresponds to a time interval of 0 to 0.29 sand. For example, to decode a count value of 8, switch 1
24 are closed and the other switches are left open, while for a count of 15 all switches 121
~124 is closed. N constituting the reference time interval signal
The output signal from AND gate decoder 25 is D-
Added to set the latch type flip-flop circuit 126.

D-latch circuit 126 is set by signal F received at terminal 128 from scan controller 93 as described with respect to FIG. The output of the D-latch circuit 126 is applied to a suitable latching switch circuit 127 of any known configuration, such as one using a silicon controlled rectifier. The output of this latching switch circuit is effective for energizing or deenergizing the on-coming clutch 50. When the D-latch circuit 126 is reset, the latching switch circuit 127 energizes the engagement clutch 50,
In contrast, setting the latch circuit deenergizes the clutch. FIG. 10 is a representative timing diagram for a flex height control system 110 according to the present invention.

The copy machine's print switch 90 is a time tank song. When activated, the engagement clutch is energized to begin sheet feeding. After a predetermined time interval during sheet feeding, the bending control system biasing device 100 consists of a 0-latch.
is energized at time t,. Front green sensor switch 8
1 then starts timer 104 activated by the front green of the first fed sheet at time t2. After a reference time interval t8-t2, a timer deenergizes the on-coming clutch at a time interval. At time t4, the energizing device 10 is reset by the master counter 117. At time, the total length of the sheet fed first is determined by sensor switch 8.
1 is passed and the sensor switch is deenergized. time t'
When the next copy starts at o, the above timing and
The cycle repeats. After forming a forward bend in the sheet with respect to the alignment gate 80 in this manner, the sheet is moved to the alignment row 2 in order to transfer the original image to the sheet.
It is necessary to send the image to the nip section 4 and then to the image forming section 11. Since a relatively high curvature has been formed in the sheet, in order to feed the sheet without jamming, it is necessary to assist in flattening the curvature of the sheet as the sheet is fed by the alignment roll. is necessary and desirable. As shown in FIGS. 7 and 11, when the sheet P is blocked by the alignment gate 801, the front green of the sheet P rests on the lower alignment roll 27.

The lower registration roll has a diameter that is larger than the diameter of the upper registration roll 28. Since the gate 80G in the sheet blocking position is located upstream of the nip of the roll 24 and sufficiently close to the nip of the roll 24, the front green of the sheet is prevented when the sheet engages with the gate. It can be placed on the lower alignment roll. Since the roll 24 is continuously driven, the effect of such a configuration is that after a predetermined bend is formed, sheet feeding by the separator 2 is interrupted, and when the bend is flattening, the gate 8
0 rotates clockwise, and the front green of the sheet remains engaged with the gate 80 while the sheet enters the nip between the rotating rolls 24, so that the bending of the sheet caused by the gate 8 is prevented. It is possible to obtain an auxiliary force for flattening. Furthermore, since the sheet is positioned on the rotating roll 27 even during the bending process, the sheet can be effectively fed by the rolls 27 and 24 after the bending process.
The registration gate 80 shown in FIGS. 7 and 11 also serves as an upper paper guide for the registration roll 24.

This gate substantially lengthens the sheet.
The portion of the gate 80 that engages the leading edge of the sheet during alignment includes a paper stop member (tab) 130, and the remaining plate-like surface portion 131 constitutes a paper guide. As previously mentioned, the assistance of the lower registration roll assists in maintaining engagement between the front green of the sheet and the taboo 30.
An alignment gate 80 is located downstream of the bend formed in the sheet.
It engages with the guide portion 131 of. In the illustrated embodiment, guide 131 and tab 30 are formed as a single piece.
As the guide 131 pivots as the sheet P enters the nip of the registration roll 24, the auxiliary action on the front of the sheet helps drive the sheet into the registration roll and reduces the tendency of the sheet to jam. given to do. If the pivoting type alignment gate 80 were configured so that the guide portion 131 remained stationary and only the taboo 30 pivoted, there would be a greater tendency for jamming to occur. By pivoting the upper guide 131 and the alignment tabs 130 together, the tendency to jam is substantially reduced.

This occurs because the bend-engaging guide moves in substantially the same direction as the sheet, thereby reducing the tendency of the sheet to become entangled with the guide. As shown in FIG. 7, in order to further flatten the bending, a plurality of bending auxiliary members 14 are spaced apart in the transverse direction (perpendicular to the drawing), and when the sheet P is fed by the alignment roll 24. It acts on the upstream side of the bend to push the bend and flatten it.

This auxiliary member consists of an elongated member pivotally mounted so as to be biased towards the rear, ie upstream, side of the bend. The illustrated member is made of metal and is biased by its own weight. The weight of these members generates sufficient auxiliary force to provide the required maneuverability. Alternatively, as shown in FIG. 14, the bending aid is constituted by an elastic strip 141 made of reinforced polyester film or other suitable material that can be mounted in a cantilevered manner. As the bend is formed, the bend causes the elastic piece 141 to swing in a manner similar to a spring. The resilient piece then acts like a cantilever spring to force flattening of the bend as the sheet is being fed by the registration rolls. Identical alignment roll 24
The use of polyester film fingers is very effective when using two sheet feeding devices to feed the sheets into the gate 80 and gate 80 locations. Next, the 15th A
Referring to the figure, when the upper sheet feeding device 150
When sending the image to the alignment gate, the elastic piece 141
The upwardly formed bend causes an upward deflection, and as the sheet is fed by registration rolls 24, it acts to flatten the bend.

As shown in FIG. 15B, when the lower sheet feeder 160 is feeding the sheet, the Mylar strip 141
is deflected in the opposite direction, that is, downward, due to the downward bend, and acts to flatten the bend when the sheet P is fed. Referring to FIGS. 12 and 13, yet another bending flattening device 170 is shown.
In this embodiment, the paper feeder is located adjacent to the electrophotographic driver. The alignment gate 80' is located below the sheet feed path. This gate 80' is also a pivot gate that directs the edge of the sheet into the nip of the registration roll 24. A peelable sheet or multiple pieces, such as member 171, are connected to gate 80' and engagement pad indicator member 17.
2. Member 171 thereby forms a lower paper guide member. When in the operative position to prevent passage of the gate 80' sheet, the adjustable ridge 171 is provided with sufficient deflection to create a downward bend in the sheet. This is the preferred method as it facilitates access to the sheet for jam removal. However, this concept could also be applied to upward bend formations if desired. After forming the bend, as shown in FIG. 13, in order to feed the sheet P and flatten the bend, the alignment gate is pivoted from a blocking operative position to a non-operative position below the sheet feed path, and the alignment gate is The deflection of flexible member 171 is removed, thereby holding the outer member stretched between gate 80' and engagement pad indicator member 172. The action of removing deflection in section 171 assists in flattening the bend, similar to the concept described above. Referring again to FIG. 7, it can be seen that the sheet P being fed from the separator 12 is still retained within the separator nip as the sheet is engaged by the registration rolls 24.

Although this arrangement is desirable when the separator 12 is used in situations where there is insufficient room for the separator to be longer than the sheet to differentiate the functions of sheet alignment and separation from the stack, these Interaction of functions creates serious problems. The frictional engagement between the alignment roll 24 and the sheet and the torque applied to the alignment roll are such that even if the feed belt is loose because the clutch 50 is released, the feed belt 17 and the engagement pad 38 and the drag force between the feed belt and the stack P'. One strategy that may be used to reduce the jamming force between the feed belt 17 and the engagement pad 38 is to separate the nip portions of the separator 12 as the registration rolls feed the sheet P. However, this method impairs the desired pinching function of the separator 2. Therefore, in order to maintain an appropriate pinching throat and sheet pinching within this throat, it is preferable that the separator 12 and the engagement pad not be separated. Therefore, the best way to reduce the drag force exerted on the sheet when it is fed by the alignment roll 24 is to reduce the resistance caused by the force of the feed belt 17 in a direction perpendicular to the stack P', that is, the force that presses down the stack P. It is to be.

A device has been devised to accomplish this, but it is extremely simple in nature.

It is noted that the frictional engagement separator 2, including the feed belt 17 and the engagement pad 38, pivots about the axis of the shaft 14. Referring to FIG. 6, drive pulley 19 rotates clockwise to advance timing belt 20 and separator belt 17 as shown by arrows 180 and 181. As a result, the vertical picking force exerted by the belt 17 on the sheet P during the feeding operation increases due to the addition of an auxiliary pick force to separate the sheet from the stack. It is believed that this auxiliary pick force is a result of the infrequent reaction or resistance torque of the pivot 14 of the separator 12.

The auxiliary force provided by this resisting torque is due to the input torque about the pivot point 14 and the length of the moment arm between this pivot point and the point of application of the normal force to the stack P' and to the belt 17. It is a function of frictional resistance. The rotational drive direction applied to the pivot shaft 14 is
2 must be in the direction in which the force that presses down the stack P' acts. For example, if the belt feeding device 17 is connected to a drive pulley (
If it rotates about the pivot shaft 14 in the same direction as the rotation direction of the input) 19, a vertical force will be applied to the stack. The normal force that causes belt 17 to engage stack P' during feeding consists of two components.

The first component is the normal force exerted on the stack as belt 17 is driven, which can be varied from zero to the desired level. In the embodiment of FIG. 1, this component is formed by the weight of the separator 12, frame 13, etc. balanced by the spring 19.
This component can be kept relatively low, in other words it can be a sufficient force to maintain frictional contact between the feed belt 17 and the top sheet of the stack. When driving the feed belt, another component of the normal force is applied due to the resisting torque as described above. This second component is the sixth component
In the illustrated embodiment it is substantially larger than the first component. Moreover, this second component is self-correcting. The amount of resisting torque moment is considered to be a function of the frictional resistance experienced by the belt during driving.

The main component of frictional resistance is due to the pinching friction between the belt and the engagement pad, and the other component of frictional resistance is due to the friction between the belt and the top sheet of the stack. The self-correcting effect occurs as follows. When the sheets of the stack are sandwiched between the separator nip portions, the frictional resistance between the engagement pad 38 and the belt 17 has a correspondingly larger vertical auxiliary force than the frictional resistance between the belt and the sheet. added to the stack. Thus, the large vertical forces required to separate and feed sheets from the stack are automatically applied. If the seat is already wedged in the pinch between the belt and engagement pad, the applied normal force will be reduced. In this case, only a small normal force is required to advance the sheet since the sheet is already separated from the stack. The seat engages with the pad 38
When it is caught in the nip between the feed belt 17 and the feed belt 17, the frictional resistance of the nip is small due to the belt and the sheet, so this resistance around the pivot has a perpendicular auxiliary force or pick force component due to the torque, i.e. The force component separating the sheets from the stack is also reduced. When such a pick force is used as a vertical auxiliary force during sheet feeding,
A real advantage is obtained that the normal force for sheet feeding can be automatically corrected under different conditions. The amount of vertical force produced by this additional resistive torque component can be adjusted by adjusting the input torque about the pivot axis 14 and by adjusting the length of the hawk's moment arm with the point of vertical force application as the pivot point. I can do it.

Although the use of such pick forces has been described with respect to the use of frictional engagement separators of the type including belts and pads, 1
It may also be used with rolled frictional engagement separators such as those described in U.S. Pat.

If desired, the vertical assist force can be further increased by locating the pivot 14 out of the plane of the sheet being fed, as in Fun et al. US Pat. No. 3,048,393.

Such a configuration provides a picking force due to frictional resistance between the sheet feeding device and the sheet. However, the picking force in this case varies depending on the stack height. The actual speed of the feed belt may be varied by adjusting the input torque to pulley 19 by any desired means, such as variable pulley 18 or a suitable gearing system.

However, it is essential that the drive direction around the pivot is proper, and therefore it is necessary to add idle gears, etc. to obtain the proper input drive direction.
The sheet separator 12, mounted as described above, exerts a large initial normal force on the stack P' during sheet feeding by the separator, and then a practically small normal force when the sheet P is fed by the registration rolls 24. It is designed to give

Therefore, the drag force of the sheet feeding device acting on the sheet as it is fed by registration rolls 24 is substantially reduced. Referring to FIG. 14, an example in which the principle of pick force is applied to a lower sheet feeding device 1601 is shown.

In FIG. 14, two sheet feeding devices 160 and 160 are used. Upper sheet feeding device 150
is practically equivalent to the previously described feeding device, with the only difference being that the feeding belt 17' is provided with an additional idler pulley 151. Therefore, the surroundings of the belt 17' are not substantially different from those of the belt used in the lower sheet feeding device 160. The belt section between idler pulley 151 and rear belt pulley IJ16' operates as described above. Feed belt 17' and engagement pad 38'
pivots about axis 14' as described above. By the way, there is a lower sheet feeding device 160' in which a belt 17'' feeds sheets from the bottom of the stack P'.
Here, a large portion of the feed belt between idler pulley 161 and pulley 162 engages the lower sheet to effect efficient feeding.

This is a method similar to that described in US Patent Application No. 342,653, filed March 19, 1973. The feed belt 17'' and engagement pad 38'' in the lower sheet feeder pivot about the drive shaft 163 relative to the stack P'. Input drive gear 164, which meshes with drive gear 48 (not shown in FIG. 14), rotates counterclockwise. The rear pulley 16'' of the feed belt 17'' is connected to the input drive gear 164 by a pulley timing belt arrangement similar to that described above with respect to the feed belt 17 of FIG.
Driven from. In this way, a pick force or vertical auxiliary force is generated during sheet feeding. The pick force is the vertical force exerted on the bottom of the stack by the feed head 1.
7'' and 38'' to a value that is substantially greater than the force exerted by spring 165. In the case of the upper sheet feeder 150, the stack support pan is the stop against which the pick force of the feed belt 17' acts. However, in the case of the support pan of the lower sheet feeder 160, no such stack stop is provided. An adjustable stop device 200 is provided, on which the feed belt 17'' acts.

An adjustable stop device 2001 is provided with a pivot lever 201. This lever 201 has a pad 2 at one end for contacting the stack P' above the feed belt 17''.
It has 02. The other end of the lever is one-way clutch 2
04 to the shaft 203, this lever is subjected to a predetermined force selected to be greater than the vertical pick force exerted by the feed belt 17''.
A one-way clutch 204 facilitates movement of the lever 201 towards the stack, but away from the stack unless it slips due to the application of a force substantially greater than the pick force applied to the stack by the feed belt 17''. In operation, the adjustable stop lever 201 is raised to load the sheet stack and then lowered against the stack. When the seed P is being fed, the pick force A large normal force is exerted on the pad 202 and the lever 201, which suppresses or restrains the stack from moving, increasing the normal force that must be applied to the stack. Even when no force is applied, spring 165 biases the bottom of the stack with a low level of normal force.
Two sheet feeders 150 and 160 are provided that feed paper to a set of registration rolls 24, in which case a sheet being fed from either sheet feeder to the rolls is first fed by the rolls. is still present within each sheet feed separator even when the

The respective feed belts 17' and 17'' of the upper sheet device 150 and the lower sheet device 160 in FIG. 14 are offset from each other in the transverse direction of the feed direction.

One of the problems that arises when using a separator 2 such as the frictional engagement separator described here or the alignment roll 24 described earlier is that the tension in the sheet is uneven between the alignment roll and the separator and between the separators. Because of this, force is applied unevenly to the sheet.

This is best explained with reference to Figure 16A.
When the alignment rolls 24 begin to advance the sheet P and pull it out from the nip of the separator 12, the force distribution pattern is formed as shown in FIG. 16A. This force distribution pattern is such that the registration roll extends across the transverse width of the sheet, whereas the separator is essentially at a single point on the sheet, resulting in a very non-uniform force distribution. This uneven distribution of forces results in distortion or wrinkles in the sheet as it is fed by the registration rolls, as shown in FIG. 16B. When a sheet with a wrinkled leading edge or a corrugated front green is fed to the imaging member 1, the copied sheet will have transfer defects where the sheet does not contact the imaging member due to its corrugated surface. will occur. Such defective transfer areas are
Since it extends inward from the front green of the sheet in a finger-like manner, it is characterized as a finger-like transfer defective area. One way to solve this problem is shown in Figure 7, which shows:
A protrusion 210 is provided at the bottom of the lower paper guide member 43 extending between the separator and the alignment roll.

This protrusion is preferably relatively steep in order to cause runout in the paper being fed. This protrusion also helps initiate flexion. As the sheet P is fed by the alignment roll 24 while still being held within the separator nip, the sheet has a sharp bend 210 as shown in FIG. 17A.
' is formed. The effect of this curved portion is that since the roll pulls against the linear protrusion 2101, a uniform force distribution is provided between the curved portion and the alignment roll. Although there may still be an uneven force distribution between the separator 12 and the curved portion 210' of the sheet P formed by the protrusion 2101, as shown in FIG. 17B,
As a result of forming the curves in the sheet, the leading edge of the sheet is free from wrinkles and undulations, thereby reducing or eliminating the finger-like transfer defects described above. 1st
FIG. 8A shows yet another method for removing wavy or wrinkled portions from the front green of the sheet P fed by the alignment rolls 24.

According to this method, the alignment rolls 220 and 221 that contact the sheet near opposite edges of the sheet are tilted somewhat toward the center of the sheet. These rolls are generally tilted with respect to the axis of the upper alignment roll axis 222. The rotation axis of the alignment roll 221 on the right side of the seat is tilted to the right with respect to the center of gravity of the shaft 222, and the rotation axis of the alignment roll 220G on the left side of the seat is inclined to the right side with respect to the center of gravity of the axis 222. It is tilted to the left. The inclination of the rolls 220 and 221 can be obtained by providing an eccentric marrow receiver (not shown) relative to the axis 222 about which the rolls rotate. Regarding the details of this construction, any method is possible for tilting the rolls 220 and 221 toward the center of the sheet, including bending the shaft 222 by the desired tilt angle. In the illustrated device, only the outer upper idler rolls 220 and 221 are tilted, and the driven lower roll 27 is not tilted. If desired, both sets of rolls may be perverted. However, preferred results are obtained if only the top outer roll is sloped. That is, the effect of tilting rolls 220 and 221 is that each roll applies an outward force transversely to the sheet feed direction on each side of the sheet, thereby imparting tension on the sheet along the transverse width of the sheet. The purpose is to smooth out wrinkles, distortions or corrugations in the sheet.
Although a central registration roll 28 is shown, this may not be used. If a central registration roll is used, it is preferable to mount it flush against the center of the shaft 222, rather than tilting it in either direction. It has been found that if the sheet is fed by the separator without the front portion 43' of the lower paper guide member, wrinkles may form at the leading edge of the sheet.

The part of the sheet that is acted upon by the separator follows the curved path of the separator's nip, whereas the remaining part of the sheet tends to follow a straight path due to its inherent beam strength. . In addition, wrinkles may occur in the front twill portion of the sheet. To solve this problem, the front portion 43 of the lower paper guide member 43, which is approximately coextensive with the separator 12, is formed so that its transverse width substantially matches the shape of the separator nip. be done. This section, together with the upper guide member 70, forces the entire sheet to follow the arcuate path of the separator nip, thereby reducing the tendency of the sheet to wrinkle. The shape of portion 43' is similar to, but need not be exactly the same as, the shape of the nip.

Portion 43' should have a curved shape sufficient to guide the sheet across its transverse width through a curved path that is substantially identical to the nip. Referring again here to the use of the pick force as a vertical auxiliary force during feeding, especially in the lower sheeting device, the initial vertical force is preferably zero and the total vertical force applied to the stack by the sheeting device is auxiliary. This method, which preferably consists of a force, can also be applied to an uppersheet arrangement by providing a counterbalancing force sufficient to counterbalance the weight of the feed head.

However, it has been found that good results are obtained in the top sheet device by applying a small initial normal force. - The pick force generated by the sheet feeding device of the invention has very useful side effects, including the periodic application of a relatively large pick force to the leading edge of the stack. This also includes easily tearing off the front green part. To further illustrate the use of pick force as a vertical assist force, an example calculation is provided for the sheet feeder of FIG. 6 with the following parameters: 1
The moment caused by the weight of the swivel feed head is
Approximately 1.31 [9. skin (approximately 1.15 in.lb).

2 Bearing friction assumed to occur only in pulley 16 is:
Approximately 0.127k9. (approximately 0.097 in.lb).

3. The horizontal distance from the pivot 14 to the point of contact with the stack is approximately 4.56 inches and the vertical distance is approximately 0.45 inches.
It is.

4. The angle at which the belt 17 wraps around the engagement pad 38 is approximately 23.3 degrees.

5 The initial belt hearing is approximately 0.67k9 (approximately 1.51b)
).

6 The diameter of pulley 19 is about 2 times the diameter of the drive hub of pulley 16 around axis 15, and the diameter of pulley 16 is about 2 times the diameter of the drive hub of pulley 16 around axis 15.
．． 32 skin (approximately 0.915 inches).

7 The friction coefficient of the belt against the engagement pad is approximately 1.58
, the coefficient of friction between the sheets is approximately 0.6,
The coefficient of friction between the seat and the engagement pad is approximately 1.1.

Based on the above parameters, the following force levels were calculated:

When the sheet feeder is not running, the normal force it exerts on the stack is approximately 0.11k9 (approximately 0.251b
). During operation, the auxiliary pick force increases the normal force to approximately 0.29 kg (approximately 0.61 b) if the sheet is not caught in the separator nip, or if the sheet is caught in the separator nip. Approximately 0.19k in case
9 (approximately 0.421b). This illustrates the self-correcting effect of the pick action of the present invention. In addition to the force calculated as described above, the sheet is not fed and the belt 17
The following forces were calculated for the drag force required to pull a sheet from the sheet feeder when it is idle.
The bearing drag force is approximately 0.094k9 (approximately 0.211b).

The drag force of the feed belt against the stack is approximately 0.068 kg.
(approximately 0.1511b). The drag force of the delay pad against the belt is approximately 0.299k9 (approximately 0.6661b).

The total drag force is therefore approximately 0.46 kg (approximately 1.03 b).

It is clear that the drag force at the separator nip is more than four times greater than the drag force between the belt and stack. Therefore, the pick force generated is primarily a function of the pinch friction. If the total normal force were to be applied to the feed head instead of using pick force assistance,
It will be clear that the belt-to-stack drag will be extremely large.

This example is for illustrative purposes only and is only one embodiment of the invention, and is not intended to limit the invention.

A sheet feeding device using the principles disclosed herein can use a wide range of parameters to achieve the desired level of force as well as other characteristics. The sheet feeding device of the present invention is suitable for use in copying machines, especially electrophotographic copying machines.

Its highly compact nature makes it possible to substantially reduce the space required for the sheet feeding device. Although the sheet feeding device of the present invention can be used in any desired copying machine, an electrophotographic copying machine will be described below with reference to FIG. Referring to FIG. 14, an electrostatographic copying machine 230 equipped with the improved sheet feeder 10 of the present invention.
is shown as an example. The copying machine 23 shown in FIG. 14 uses various components therein to make electrophotographic copies of original documents. Although the sheet feeding apparatus of the present invention is particularly suitable for automatic electrophotographic copier 2301, it is equally applicable to a variety of electrostatographic systems and other copiers, and is suitable for use in the specific embodiment shown herein. is not necessarily limited. The copying machine shown in FIG. 14 uses a drum-shaped member 231 for recording images, the outer periphery of which is coated with a suitable light-conducting material.

One type of suitable photoconductive material is described in U.S. Pat. No. 2,970, issued to Bixby in 1961;
No. 906. The drum 231 has a shaft 232
The holding surface is rotatably mounted within a machine frame (not shown) in the direction indicated by arrow 233 to bring the retaining surface to a plurality of xerographic processing positions.
Suitable drives (not shown) are provided to drive and control the operation of the various cooperating components, so that a faithful reproduction of the original image information can be obtained from the sheet P of paper or other material. recorded above. The practice of electrophotography is well known in the art, and there are many patents and publications in this regard, including:

For example, Chef Art (Sc) published in 1963
"Electronic Photography" by
Ho's qraphy), and Dessa and Clark, published in 1965.
“Electrophotography and Related Processes (Xeroqr)” by
aphyandPelatedProcess). The various processing locations for forming copies of original documents are shown in FIG. 14 as blocks 234-239. Initially, drum 231 moves the photoconductive surface to charging position 234 .

At charging location 234, an electrostatic charge is uniformly placed on the photoconductive surface of drum 231 in preparation for imaging. This charge is caused by 195 breast milk.
No. 2,836,725, published in 1999, published in US Pat. No. 2,836,725.
After this, the drum 231 rotates and comes to the exposure position 235.

where it is exposed to a light image of the photoconductive surface and document image information, thereby selectively dissipating the charge in the exposed areas;
Original image information is recorded in the form of a static latent image. A suitable exposure apparatus is disclosed in U.S. Patent Application No. 2, filed June 2, 1972.
59,181.
After exposure, drum 231 rotates the electrostatic latent image recorded on the photoconductive surface to a development position 236, where a conventional developer mixture is applied to the photoconductive surface of drum 231 to form the latent image. Develop.

The appropriate development position was determined by Reichart in 1973.
U.S. Patent No. 3,707,94 issued to
It is disclosed in No. 7. This patent describes a magnetic brush development device that uses a magnetizable mixed developer including particulates and toner for coloring. The mixed developer is continuously deflected through a directional magnetic field to form the brush. The electrostatic latent image recorded on the photoconductive surface is developed by contacting it with a brush of mixed developer material. The developed image on the photoconductive surface is then contacted with a sheet of final support material P at transfer layer 237.

This transfers a toner image from the photoconductive surface to the contact surface of the sheet. The sheet may be of paper, plastic, etc. as desired. After the toner image is transferred to the sheet, the sheet with the image on its surface is advanced to a suitable fusing device 238, which fuses the transferred powder image to the sheet. One type of suitable fusing device is disclosed in U.S. Pat. No. 2, issued in 1958 to Codichini et al.
, No. 701,765. Although most of the toner powder is transferred to the sheet P, it is inevitable that some residual toner remains on the photoconductive surface after copying.

Residual toner particles that remain on the photoconductive surface after copying are removed from drum 231 as it moves through cleaning position 239. In this case, the toner particles are first neutralized and then, for example,
U.S. Patent No. 3,660,86 issued to
The photoconductive surface is mechanically cleaned by suitable means such as using a resiliently biased knife blade as described in No. 3. It is believed that the foregoing description is sufficient to indicate the general operation of an automatic electrophotographic reproduction machine embodying the present invention. Except as otherwise specified and illustrated, it is suitably supported within a suitable frame by any desired conventional means on shafts or other members. As used herein, the term electrostatography refers collectively to the formation and use of electrostatic charge patterns for the purpose of recording and reproducing visible patterns.

Effects of the Invention According to the configuration of the present invention described above, various types of copy paper (for example, transparent paper, opaque paper, relatively soft paper, or hard paper) can be used without jamming or loosening the paper. Paper can be fed to photosensitive drums, etc., and
Since the height of the convex curvature of the paper can be precisely controlled, there is an effect that an appropriate convex curvature can be formed according to the conditions of use (temperature, humidity, etc.).

According to the present invention, an apparatus is provided that fully satisfies the above-mentioned objects, configurations, and effects.

Although the invention has been described with respect to specific embodiments, many modifications will be apparent to those skilled in the art in light of the foregoing description.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the sheet feeding device of the present invention in its operating position, FIG. 2 is a perspective view showing the sheet feeding device of FIG. 1 with the paper drawer extended, and FIG. FIG. 4 is a series of partial side views illustrating a sheet feeding apparatus according to the present invention;
FIG. 5 is a partial perspective view showing a drive connection device according to the present invention; FIG. FIG. 6 is a partial side view of a sheet feeding device according to the present invention, FIG. 7 is a partial side view of a sheet feeding device according to the present invention, and FIG. 8 is a flowchart showing an electrical bending height control system according to the present invention. , FIG. 9 is a circuit diagram showing the electrical bending height control system according to the present invention, FIG. 10 is a timing diagram for explaining the operation of the electrical bending height control system according to the present invention, and FIG. , FIG. 12 is a partial side view showing a modification of the bending assist mechanism according to the invention, and FIG. FIG. 14 is a partial side view showing the mechanism according to the modified example in its operating position.
FIG. 15 is a schematic side view showing a copying machine equipped with an upper sheet feeding device and a lower sheet feeding device according to the present invention; FIG. 15 is a series of partial side views showing the operating state of the sheet feeding device of FIG. 14; FIG. Top and front views illustrating the effect of holding the sheet together with the alignment rolls and the outside of the separator;
FIG. 17 is a top and front view illustrating the effect of the pre-alignment protrusion in the sheet feed path, and FIG. 18 is a top and front view illustrating the use of lead-opening rolls. 10... Sheet feeding device, 11... Sheet support drawer, 12... Frictional engagement separator, 13.
．．・．． ．．・Swivel frame, 17, 17', 17''...
・Feed belt, 20... Timing belt, 2
2... Drive device, 24... Positioning pinch/low-fu, 32, 33... Side guide, 34... Restraint odor, 35... Transfer device, 3
8, 38', 38''...Engagement pad, 12...
...Frictional engagement separator, 13...Swivel frame, 17, 17', 17''...Feed belt, 20...
...Timing belt, 22...Drive device, 24
...Positioning pinch low-fu, 32, 33.
．． ...Side guide, 34...Restraint, 35.
...Transfer device, 38, 38', 38''...
・Engagement pad, 40, 41...Swivel side plate, 42
Loading plate, 43 Lower paper guide member, 44 Support plate, 46 Drive connection device, 50 Clutch , 54... Micro switch, 55... Actuator, 60... Toggle mechanism, 62... Toggle member, 64, 65.
...,.・Adjustment screw, 81...Front green sensor, 8
2...Timer, 113...Noise suppression circuit,
130... Stopping tab, 131... Guide surface portion, 140, 141... Bending auxiliary member, 150...
...Upper sheet feeding device, 160...Lower sheet feeding device, 171...Movable member, 2
00... Stop device. (NG/ (NG2. 'ノG 34 'NG 38 enemy G child power G u A row 硲68 'ノG.6 (NG a(nG8 〃4 Rows G//8 (Force G Ne (Force G is batting force G/Sub-hitting Su G'5A1 Batting Su G'68 Batting force G/64 (N G /680,000 Su G'Ar'n○ /A8 Batting power G^84 (S G^88

Claims (1)

[Claims] 1 comprising a stop member 130 that engages the edge of a sheet of paper and stops the advance of the edge of the sheet, and a feeding device 10 that feeds the sheet of paper relative to the stop member to bend the sheet of paper into a convex shape; The paper feeding device for forming a convex bend in the paper sheet includes (a) a sensing device 81 that senses the position of the edge of the sheet; and (b) a sensing device 81 coupled to the feeding device and responsive to the sensing device. A device 50 that measures a reference time after sensing the edge and stops the feeding device after the reference time.
(c) the reference time is determined to be long enough for the feeding device to form the predetermined convex bend in the sheet; and (c) the reference time is a desired time. a device for adjusting the height of the convex bend 121, 122, 123, 124, comprising a device for adjusting the timing device so as to be adjustable to a value;
125. A paper feeding device comprising: 125.