JP2916827B2 - Paper stacking apparatus and paper stacking method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet stacking apparatus for stacking sheets discharged from an image forming apparatus such as a copying machine or a printer on a discharge tray, and a method for stacking sheets on a discharge tray.

[0002]

2. Description of the Related Art Conventionally, for example, JP-A-62-20046, JP-A-62-191375, and JP-A-62-191375.
176246, JP-A-62-290669, JP-A-59-82263, JP-A-63-10
As described in, for example, Japanese Patent No. 1268, the recording paper sent from the image forming apparatus is stored in a staple tray to bind the recording paper, and the bundle of the bound recording paper is dropped to a lower tray and discharged. An image post-processing apparatus for performing a bookbinding process is generally known.

Some bookbinding processing apparatuses include a discharge mechanism for discharging and storing the recording paper as it is or in a line, and the recording paper discharged from the image forming apparatus is discharged by the discharge mechanism and the discharge mechanism. The guide is selectively guided to one of the staple mechanisms.

A conventional example of this kind will be described with reference to FIGS.

The finisher shown in FIG. 2 is provided on a side portion of an image forming apparatus (not shown), and includes a shift sorting section I on an upper side and a staple section II on a lower side. .

First, a plurality of transport rollers and a driven roller that follows the transport rollers are arranged on the transport path of the shift sorting section I. The rotation axis of the first conveyance roller 101 is connected to the conveyance drive motor M1 via the first timing belt 104.
, Thereby obtaining a driving force. The rotation axis of the first conveyance roller 101 is connected to the rotation axis of another conveyance roller, the rotation axis of the discharge roller 102 and the rotation axis of the shifting brush 103 by a second timing belt (not shown). To drive.

An entrance sensor SN1 is provided immediately before the uppermost transport roller 101.
A discharge sensor SN2 is provided immediately before the discharge roller 102.
Is provided so that the leading and trailing ends of the conveyed paper are detected. The first transport roller 1
A switching claw 105 is disposed downstream of the staple unit 01 and the driving direction of the staple unit II and the shift sorting unit I tray unit to be described later by the action of a driving solenoid 230 and a spring (not shown). Can also be changed.

As shown in FIGS. 3, 4 and 5,
In the vicinity of the discharge port, a paper shift brush 103 is disposed immediately below the discharge roller 102, and the recording paper dropped on the discharge tray 107 is moved toward the abutting plate 106 by the rotation thereof. The recording paper is abutted against the abutting plate 106 so that the rear end of the recording paper is aligned.

Next, in the shift drive mechanism, as shown in FIG. 4, irregularities are formed on the abutment plate 106 and the discharge tray 107 so that they are engaged with each other. As a result, the discharge tray 1
07 is freely movable in the vertical direction (the direction perpendicular to the paper surface of FIG. 4) with respect to the abutment plate 106, and is movable in the front-rear direction (FIG. 4).
In the left-right direction (on the paper surface), it is moved in conjunction with the abutment plate 106. In FIGS. 5 and 6, the abutment plate 106 has a shaft-like shift guide 112 via a bearing 111 on a main body side different from the discharge tray 107.
And is configured to be freely movable in the front-rear direction. As shown in FIG. 6, the abutment plate 106 is connected to the crank 1 via the arm rod 115.
13 and is eccentrically connected. The rotation axis of the crank 113 is arranged parallel to the center axis of the copying machine. Side plate 1
Detachable bracket 116 vertically projecting from 00
Is provided with a gear train 114, and the crank 113 is connected to the shift motor M2 via the gear train 114. The crank 113 is driven by driving the shift motor M2, and the abutment plate 106 is reciprocated in the front-rear direction by the eccentric rotation action. Therefore, the discharge tray 107 regulated in the front-rear direction with respect to the abutment plate 106 is also reciprocated in the front-rear direction. The shift plate 106 is provided with two shift detection plates 118 projecting from the abutment plate 106 at an interval substantially equal to the amount of movement by the crank 113. The detection by the detection sensor 117 detects that the butting operation and the tray shift operation have been moved by one stroke.

As shown in FIG. 7, a press roller 108 is vertically and rotatably supported via a bracket 119 fixed to the abutment plate 106, whereby the discharge tray 107 is supported. The upper surface of the stacked recording paper is pressed by its own weight. The recording paper is held down by the pressing roller
08, and is abutted against the abutment plate 106. The discharge tray 107 is pressed by the pressing force of the press roller 108.
Is shifted, recording paper misalignment is prevented. A paper surface detection sensor SN3 is arranged on the main body side to face the press roller 108. When the position of the press roller 108 is raised by stacking the recording paper, the paper surface detection sensor SN3 is moved to the press roller support bracket 120. Is detected, and it is known that the paper surface or the upper surface of the discharge tray has reached a specified height.

FIGS. 8 and 9 show a vertical movement mechanism.
As shown in the figure, the discharge tray 107 is fixed to the tray support 110. The tray support table 110 is supported by a tray vertical movement table 109 via a bearing 110a so as to be movable back and forth. Therefore, as described above, the shift operation by the butting plate 106 is performed by the
It can be performed by the following. As shown in FIG. 2, the tray vertically moving table 109 is fixed to the third timing belt 120. The third timing belt 120 is provided one by one on the outside of the front and rear side plates 100, and each of the third timing belts 120 is a vertically driving pulley 121.
And the driven pulley 122. The vertical drive pulley 121 is fixed to a vertical drive shaft 123 that both pass through between the side plates.
3 is provided with a gear 124 containing a one-way clutch. One way clutch is the output tray 1
It is configured to transmit a force in the direction of lifting the 07 to the vertical drive shaft. The gear 124 is connected to a vertical drive motor M3 via a gear train, a worm wheel 125, a worm 126, and the like. A bearing 127 is attached to a side surface of the vertical motion support table 109, and is brought into contact with a vertical guide rail 128 fixed to the side plate 100, so that a vertical motion guide and a rotational moment due to the weight of the discharge tray are provided. To prevent the discharge tray from falling down.

With the construction described above, the lowering of the discharge tray 107 is normally stopped by the holding force of the worm 126 and the one-way clutch being locked. Vertical drive motor M
3 is rotated in the upward direction of the discharge tray 107, the one-way clutch is locked, and the pulleys 121,
122 is rotated, whereby the discharge tray 107 is raised. The vertical drive motor M3 is connected to the discharge tray 107.
Is rotated in the downward direction, the one-way clutch is in a free state, whereby the discharge tray 107 is moved downward by its own weight.

Further, as shown in FIG. 10, an upper limit sensor SN4 and a lower limit sensor SN5 are provided inside the timing belt 120 so as to face the discharge tray 107, and each of them detects the upper and lower detection plates 129. As a result, the upper and lower limits of the discharge tray 107 are detected. When the discharge tray 107 is lowered, the one-way clutch is in a free state. Therefore, even if the driving force of the vertical drive motor M3 is not transmitted to the discharge tray 107 and the discharge tray 107 is stopped by the external force at the time of lowering, When the vertical drive motor M3 idles, troubles such as overload of the motor and pinching of fingers are prevented.

When the copying operation is started, the shift motor M2 is driven to rotate the crank 113, so that the abutment plate 1 is connected to the crank 113 via the rod 115.
06 is moved in the front-back direction. Abutment plate 1
The discharge tray 107, which is engaged with the irregularities of No. 06 and supported so as to be able to move up and down and back and forth, is moved in the front and rear direction to start the shift operation. And the shift sensor 117
When the other shift detection plate 118 that is different from the one detected before the start of the shift operation is detected, the shift motor M2 is stopped by the signal to end the shift operation. After the shift operation is completed, the vertical drive motor M3 is driven in the tray raising direction to raise the discharge tray 107. After the start of the vertical movement, a part of the support bracket 120 of the presser roller 108 is detected by the paper surface detection sensor SN3 or the upper limit sensor SN.
4 detects the up / down detection plate 129, the vertical drive motor M3 is stopped by the signal, and the lifting of the discharge tray 107 is completed. When the paper surface sensor SN3 detects the support bracket 120, the vertical drive motor M3 is driven in the tray lowering direction, and the vertical drive motor M3 stops when the paper surface sensor SN3 stops detecting the support bracket 120. .

The transporting roller 101 receives the recording paper discharged from the main body at the same linear speed as the discharge speed from the main body. When the recording paper is conveyed and the entrance sensor SN1 detects the trailing edge of the recording paper, the linear velocity is increased to a value greater than the recording paper ejection speed, and the trailing end of the recording paper is moved to the entrance sensor SN.
After a predetermined time from the detection at 1, the linear speed is returned to the main body discharge speed of the recording paper, and then the recording paper is discharged to the discharge tray 107. The recording paper discharged to the discharge tray 107 is moved under the holding roller 108 by gravity and the conveying force of the rotation of the fur brush 103, and is abutted against the abutting plate 106 so that the trailing edge is aligned. ing.

At this time, when the specified number of copies are discharged, the shift motor M2 is driven by the signal, and the shift operation is started. Once the one-stroke shift is completed,
Shift motor M2 is stopped. By this operation, the stacking position of the recording paper on the discharge tray 107 is changed, and the recording paper is sorted. Then, when a series of copying operations is completed and the final sheet is discharged, the vertical drive motor M3 is driven in a downward direction by the signal, and the operation is completed after the discharge tray 107 is lowered by a predetermined amount. ing.

When a certain amount of recording paper is accumulated and the paper surface approaches the discharge port and a part of the presser roller support bracket 120 is detected by the paper surface detection sensor SN3, the vertical drive motor M3 is moved in the tray lowering direction by the signal. Driven,
The holding force of the worm 126 and the lock of the one-way clutch are released, and the discharge tray 107 is lowered by its own weight. When the discharge tray 107 is lowered, the paper surface is lowered, and when a part of the presser roller support bracket 120 is not detected by the paper surface detection sensor SN3, the vertical movement drive motor M3 is stopped by the signal, and the worm 126 is held. The output tray 107 is stopped by the force and locking of the one-way clutch. Discharge tray 10
7, the vertical drive motor M3 is stopped by a signal when the vertical movement detection plate 129 is detected by the lower limit sensor SN5, and the discharge tray 107 is further moved.
Is prevented from being lowered.

FIGS. 2, 10, 12, and 13 show the stapler moving mechanism in the stapling section II.
The stapler S is fixed to the stapler base 31 as shown in FIG. The stapler base 31 is engaged with a guide hole 30b of the stapler slider 30 via a guide pin 32 so as to be movable in the n direction in FIG. Further, a shaft 44 is fixed to the back side of the stapler base 31, and the guide roller 34 is rotatably attached to the shaft 44. The upper portion of the stapler slider 30 is mounted so as to be slidable in a direction perpendicular to the plane of FIG. 12 using a guide rod 36 bridged between the side plates 41 and 42 as a guide, and is mounted on a lower portion of the stapler slider 30. The guide roller 33 is abutted so as to roll on the surface of the stay 43 on the main body side, whereby the stapler slider 30 is locked in the rotation direction. A guide cam 35 is fixed to the stay 43, and the guide roller 34 is in contact with a cam surface formed on an upper end side of the guide cam 35 so as to roll. The stapler slider 3
0 is reciprocated in the direction shown in FIG. 11k.
At this time, the center portion of the guide cam 35 is formed so as to be depressed downward, along which the stapler slider 30 is moved.

At the upper end of the stapler slider 30, a detection plate 30a is provided.
Is a home position sensor 4 provided on the main body side
The home position (HP) of the stapler S is detected by blocking the 0 detection unit. The side plate 41 is provided with a stepping motor 39 for moving the stapler, and an intermediate portion of the belt 38 driven by the stepping motor 39 is fixed to the stapler slider 30, and the stapler slider 30 is moved in the horizontal direction in FIG. To be reciprocated.

Next, as shown in FIG. 11 and FIG.
A left slider 8 and a right slider 7 are attached to a jogger slot 9 bridged between 1, 42 so as to be able to reciprocate freely. And the right joga fuence 5 are fixed respectively. These left jyoga fuence 6 and right jyoga fuence 5
Has a function of performing the operation of aligning the paper bundle in the stapling operation, and also functions as a guide member when the paper bundle after stapling is discharged by extending from the vicinity of the discharge roller 3 to the vicinity of the paper discharge tray 53. have. At the lower ends of the left and right jyoga fences 6 and 5, there are provided rear end fences 6a and 5a for holding the lower end edges of the stapled sheet bundle.

An intermediate portion of the belt 10 driven by the jogger fluence drive motor 11 is fixed to the left slider 8 and the right slider 7. The left slider 8 and the right slider 7 are fixed to different sides of the belt 10, respectively, so that the left jyoga fuence 6 and the right jyoga fuence 5 are reciprocally moved in the horizontal direction in FIG. .
A guide roller 15 is attached to the upper rear side of the left and right jyoga fluences 6 and 5, and the guide roller 15 is rolled on a guide stay 16 wrapped over the upper side plates 41 and 42. Touched. The left slider 8 is provided with a detection plate 8a. The detection plate 8a shields a detection portion of the home position sensor 14 provided on the main body side, so that the home position of the two joo fuences 6, 5 is controlled. Position (H
P) is detected. As shown in FIG. 16, curl retainers 64 are provided at the lower ends of the left and right jyoga fluences 6 and 5, thereby suppressing buckling during loading on the staple tray. . The curl presser 64 is formed from an elastic member such as a polyester film.

Next, in the discharge belt mechanism, FIG.
As shown in FIGS. 14 and 15, both side plates 41, 4
The drive shaft 24 is attached to the upper end portion of the drive shaft 2 so as to extend over the drive shaft 24, and the drive pulley 18 is fixed substantially at the center of the drive shaft 24. A fixed pulley is provided below the drive pulley 18, and an endless discharge belt 17 is stretched between the pulleys 18 and 19. An intermediate portion of the discharge belt 17 is hung on an idle pulley 47 and guided by a guide plate 25 disposed inside the belt so as to prevent bending and displacement.
Further, a belt drive motor 22 is fixed to the side plate 41, and a pulley 21 attached to an output shaft of the belt drive motor 22 and a pulley 20 attached to one end of the drive shaft 24 are fixed. Belt 23
And the belt driving force is transmitted. A projection-like claw 46 is provided in the middle of the surface of the discharge belt 17 so as to grip the sheet bundle from below. As shown in FIG. 2, a home position sensor 48 for detecting the position of the claw 46 is provided inside the discharge belt 17, and the home position of the claw 46 is detected by the home position sensor 48. HP) is detected. Such a release belt 1
Conveying speed V ₂ of 7 is set in such that slightly larger than the sheet ejection linear speed V ₁ of the discharge roller _{3 (V 2 ≧ V 1)} , which in due connexion next paper bundle of Jiyobu already The paper is not discharged together with the bound paper bundle.

Each mechanism of such a stapler is configured to form one unit, and is supported by guide rails 51 and 52 so that it can be pulled out to the near side.

As shown in FIG. 2, the paper discharge tray mechanism is
The base of the paper discharge tray 53 is fixed on the tray base 54. A guide roller 56 is rotatably attached to the tray table 54, and the guide roller 56 is engaged with a guide rail (not shown) so that the tray table 54 is rotated.
At the same time, the paper discharge tray 53 is moved up and down. The tray table 54 is given an upward biasing force by a lift spring 55.

A driving force is transmitted to the conveying rollers 60, 61, and 62 from a conveying motor 59 through a belt (not shown), and a driving force is also transmitted to the discharge roller 3 from the conveying motor 59 by a belt (not shown). Have been. Fur brushes 1a and 1b are attached to the rotating shaft 2 of the discharge roller 3, and the brushes 1a and 1b are driven to rotate in synchronization with the discharge roller 3. The bristle tips of the fur brushes 1a, 1b are in contact with the guide plates 26, 27. The guide plates 26 and 27 are provided with protruding ribs 26a and 27a for holding the lower edge of the stapled sheet bundle, and the protruding ribs 26b and 27b are formed so as to protrude to the front side. . Therefore, the recording paper is bent back by the protruding ribs 26b, 27b and the pressing force of the bristle tips of the fur brushes 1a, 1b, and is deformed into a wavy shape, thereby preventing the paper bundle from buckling. It has a certain waist.

More specifically, as shown in FIG. 16, the amount L of projection of the upper guide plate 67 from the rotation center of the paper discharge roller 3 is set to be larger than the amount t of paper to be sent out. In this case, the above-mentioned fur brush 1
Even when the recording paper does not fall below the upper and lower guides 67a and 1b and enters between the upper guide plate 67 and the fur brushes 1a and 1b, the trailing end of the recording paper is scraped down by the bristle tips of the fur brushes 1a and 1b. It has become to be.

The operation of processing a recording sheet will now be described. First, a stapling operation is selected by a stapling key, a document (N sheets) is set on a document feeding table (RDH) (not shown), and a copy button is pressed after a copy number (K portion) is input by a ten key. Then, a copy size signal is received from the main body of the copying machine, and it is determined whether or not the size is such that it can be accommodated in the staple portion. In the case of a size that can be put in the staple portion, it is determined whether or not the claw 46 of the discharge belt 17 is at the home position (HP). If it is not at the home position, it is returned to the home position by the belt drive motor 22. It is detected whether or not the stapler S is in the home position. If the home position is detected, the stapler S is moved to a predetermined position by the size signal. If the home position is not detected, the home position is detected. The stapler is moved until the home position is detected until the position is detected, and then the stapler S is moved to a predetermined location according to the size signal.
Is to be moved.

It is detected whether or not the joga fuences 5 and 6 are in the home position (HP). If the home position is detected, the joga fuences 5 and 6 are moved to a predetermined location by the size signal. If the home position is not detected, the home position is detected until the home position is detected, and the home position is detected.
6 is to be moved. The moving place at this time is moved to a position amm away from the size width on one side and 2amm on both sides.

The leading end of the recording paper is the entrance sensor SN.
When the switch guide member 105 is detected, the switching guide member 105 is switched to the staple tray by the switching solenoid 230, and guidance is performed. When the trailing end of the recording paper passes through the entrance sensor SN1, high-speed feeding is performed. The switching solenoid 230 is turned off after a predetermined time, that is, a time until it passes through the switching guide member 105 after passing through the entrance sensor SN1. Discharge roller 3
As a result, the recording paper is discharged onto the staple tray, and when the recording paper is being discharged, the electric charge charged on the recording paper is removed by the discharging brush 63 fixed to the upper discharge plate guide plate 67. It has become. The discharge roller 3 is provided with a brim, whereby the recording paper is bent into a wave shape so that the recording paper can be bent.
When the trailing end of the recording paper passes through the discharge roller 3, the trailing ends of the recording paper are pushed down by the coaxial fur brushes 1a and 1b, and the trailing ends provided in the trailing ends 26a and 27a and the joggers 7 and 6. It is moved so as to be abutted against 5a and 6a. After a predetermined time after passing through the lower sheet ejection sensor 50, the driving motor 11 of the joga fuences 5, 6 which has been waiting until then repeats forward or reverse once or twice, thereby aligning the recording paper in the width direction. After such paper alignment, the printer is returned to the standby position. This paper alignment operation is repeated for each recording sheet, and is performed until the end signal of one job is issued from the copying machine main body.

Next, when the end signal of one job is transmitted and received from the copying machine main body, the above-mentioned operation is executed again, and the recording paper bundle is pressed down in the width direction by the jogger fluences 5, 6. Then, the drive motor 223 in the stapler S starts driving, and the recording paper bundle is bound. In this binding operation, it is determined whether or not one-shot operation is performed. In the case of one-shot operation, the joga fuences 5 and 6 are moved to positions slightly away from the paper bundle after the end of the binding operation.
In the case of two or more hits, the stapler is moved to a predetermined position by the stapler moving motor 39 and the binding operation is executed again. After the binding operation is performed, the jog joe fluences 5 and 6 are returned to the positions slightly escaped from the paper bundle. It is. At this time, the discharge belt 17 is rotated in the direction of m in FIG. 13, and the recording paper bundle is discharged to the paper discharge tray 53 in the same direction as the discharge direction to the staple tray while the rear end of the recording paper bundle is pushed up by the claw 46. You.

It is determined whether or not the last set number of copies (K copies) has been completed.
6 and the stapler S have been moved to the home position, and when not yet finished, the above-described operation is performed again.

In such an apparatus, the discharge tray 10
The upper and lower operations of the sensor 7 are first performed when the power is turned on or when the mode is selected.
5 and the output state of the paper surface sensor SN3 are checked by the CPU, and the position of the discharge tray 107 at present is determined. If the upper limit sensor SN4 and the paper surface sensor SN3 are turned on, the vertical drive motor M3 is turned on, and the discharge tray 107 is lowered to a point where the paper surface sensor SN3 is turned off. If only the upper limit sensor SN4 is ON, nothing is performed. When the upper limit sensor SN4, the lower limit sensor SN5, and the paper surface sensor SN3 are all turned off, the vertical drive motor M3 is turned on, and the discharge tray 107 is raised to a position where the upper limit sensor SN4 or the paper surface sensor SN3 is turned on. When the sensor SN3 is turned on, it is lowered until the paper surface sensor SN3 is turned off. When only the paper surface sensor SN3 is turned on, the vertical drive motor M3 is turned on, and the discharge tray 107 is lowered until the paper surface sensor SN3 is turned off. When the lower limit sensor SN5 and the paper surface sensor SN3 are turned on, it is determined that the recording paper is full on the discharge tray 107, a signal indicating that the paper is full is transmitted to the copying machine main body, and the recording paper is removed. After a predetermined time, the vertical drive motor M3 is turned on, and the upper limit sensor S
The discharge tray 107 is raised until N4 or the paper surface sensor SN3 is turned on. When the paper surface sensor SN3 is turned on, the discharge tray 107 is lowered until the paper surface sensor SN3 is turned off.

When restarting in the same mode, the same operation as when the power is turned on and when the mode is selected is performed in synchronization with the copy start signal of the main body.

During copying and at the end of copying, when the paper surface sensor SN3 is turned on, the vertical drive motor M3 is turned on, and the discharge tray 107 is lowered until the paper surface sensor SN3 is turned off. When this operation is repeatedly performed and the lower limit sensor SN5 is turned on, a signal indicating that the discharge tray 107 is full of recording paper is transmitted to the main body. If this operation overlaps with the tray shift operation, the priority is given to the tray shift operation. During the shift operation, the operation is on standby and is performed after the shift is completed. After the final paper has passed through the main body discharge sensor 215, a finish stop signal is transmitted. When this signal is received, the vertical paper drive motor M3 is turned on after the final paper is discharged to the discharge tray 107. Then, the discharge tray 107 is lowered by a predetermined amount, and copying paper is easily performed.

Next, when the power is turned on, the shift operation is not performed. When the shift or proof mode is selected and the mode signal is received, the shift motor M2 is turned on, the discharge tray 107 is moved, and the shift detection sensor 117 is turned on. The motor M2 is turned off. By this operation, the paper remaining in the discharge tray 107 and the paper of a new job are sorted. Such an operation is performed on standby during the tray up / down operation and performed after the up / down operation is completed. In this way, even if the recording paper remains on the discharge tray 107, the recording paper is pressed by the pressing roller 108, so that the recording paper does not shift during the shift.

At the time of copying and at the end of copying,
A shift signal is sent so that the last sheet of the copy set passes through the main body discharge sensor 215. The finisher receives this signal and the rear end of the last sheet passes over the discharge sensor SN2. Turned on,
The shift operation is started. When the shift detection sensor 117 is turned on, the shift motor M2 is turned off. The above operation has a higher priority than the tray up / down operation. During the shift operation, the tray up / down movement is on standby, and the up / down movement is performed after the shift is completed. This prevents the paper from being shifted due to the shift.

When restart is performed in the same mode, no shift operation is performed at the start of copying, and during copying, the same operation as that at the time of copying is performed.

Next, the joga fluence operation will be described. First, at power-on and at the time of selection, the CPU checks the output states of the jogger home position sensor 14 and the tray paper presence / absence sensor 205, and the following operations are performed. If only the yoga home position sensor 14 is turned on, nothing is performed. If the tray paper presence / absence sensor 205 is turned on, a signal indicating that recording paper remains on the staple tray is transmitted to the main body.
When the jogger home position sensor 14 and the tray paper sensor 205 are off, the jogger drive motor 11 is turned on and the jogger fuence 5,
6 is moved in the home position direction, and when the jogger home position sensor 14 is turned on, the jogger drive motor 11 is turned off.

During copying, at the end of copying, and at the time of restarting copying, if a paper size signal is received after the start of copying of the main body, the jogger drive motor 11 is turned on, and the jogger fuences 5, 6 are moved to a position smaller than the width of the paper. It is stopped at a position before a predetermined amount and is on standby. When a predetermined time has elapsed after the paper has passed through the paper ejection sensor 50, the jogger drive motor 11 is turned on, the jog joists 5, 6 at the standby position are moved, the papers are aligned, and the paper is returned to the standby position again. At this time, Jyoga drive motor 1
1 repeats forward / reverse rotation once to several times, whereby the joga fuences 5 and 6 are aligned in the width direction of the paper. Such an operation is performed every time the recording paper is discharged onto the staple tray.

When the last sheet of the copy set passes through the main body discharge sensor 215, a staple signal is transmitted. Upon receiving this signal, the last sheet is discharged to the staple tray, and the width of the sheet after the above-described paper alignment operation is performed. The joga fuences 5 and 6 are moved and stopped at the position where the direction is suppressed. When the stapling operation is completed, the joga fuences 5 and 6 are moved to positions slightly away from both ends in the width direction of the paper. Then, the recording paper bundle is discharged to the discharge tray 53 by the discharge belt 17. By doing so, the paper is prevented from shifting during stapling, and the jogger fluences 5, 6 are used as guides in the width direction when the recording paper bundle is discharged.

When the above operation is repeatedly performed for the number of copies and the final recording paper bundle is discharged onto the paper discharge tray 53, the jogger drive motor 11 is turned on and the jog joe fluences 5 and 6 are home-positioned. When the robot is moved in the direction and the jog yo home position sensor 14 is turned on, the jog yo drive motor 11 is turned off.

When the power of the stapler operation is turned on and the mode is selected, the output states of the one-rotation sensor 210, the needle presence sensor 211, and the stapler home sensor 212 are checked by the CPU, and the following operations are executed.

If the one-rotation sensor 210 is off and the tray discharge sensor 205 is on, it is determined that a stapling failure has occurred, and a stapler abnormality signal is sent to the main body.

When the staple presence sensor 211 is off, a stapler stapleless signal is transmitted to the main body. If the stapler home sensor 40 is on, nothing is done. When the stapler home sensor 40 is turned off, if the one-rotation sensor 210 is turned on, the stapler moving motor 39 is turned on, and the stapler S is moved in the home position direction. When the stapler home sensor 40 turns on,
The stapler moving motor 39 is turned off. If the one-rotation sensor 210 is turned off, it is determined that a staple error or a jam has occurred, and the apparatus stands by in that state. When the one-rotation sensor 210 is turned on by artificial processing, the stapler moving motor 39 is turned on, the stapler moving motor 39 is moved in the stapler home position direction, and the stapler moving motor 39 is turned off after the stapler home sensor 40 is turned on. I'm sorry.

At the time of copying, at the end of copying, and at the time of restarting copying, after the paper size signal is received after the copy of the main body is started, the stapler moving motor 39
Is turned on to move the stapler S by a predetermined amount to a position corresponding to the paper size. Next, the staple ON signal is transmitted from the main body after the final sheet of the copy set passes through the main body discharge sensor 215, and when the signal is received, the final sheet is discharged onto the staple tray, and the jog fuences 5, 6 are recorded on the recording paper. When both ends in the width direction of the bundle are pressed, the staple motor 223 is turned on to perform a stapling operation, and when the one-rotation sensor 210 is turned on, the staple motor 223 is turned off. In the case of the two-position stapling mode, the stapler moving motor 39 is turned on and the stapler moving motor 39 is turned off when the stapler S is moved by a predetermined amount according to the paper size, and the second stapling operation is performed. When such a stapling operation is repeated for the number of copies and the final bundle of recording sheets is stapled, the stapler moving motor 39 is turned on, the stapler S is moved in the home position direction, and the stapler home sensor 40 is turned on. The stapler moving motor 39 is turned off.

Next, the operation of the discharge belt will be described.

When the power is turned on and the mode is selected, the CPU checks the output states of the belt home sensor 48, the tray discharge sensor 205, and the rotation sensor 210, and the next operation is performed. When the belt home sensor 48 is turned on and the tray discharge sensor 205 is turned off, nothing is performed. If both the belt home sensor 48 and the tray discharge sensor 205 are off, it is determined that the discharge belt 17 has not returned to the home position, and the belt drive motor 22
Is turned on, the discharge belt 17 is operated, and when the belt home sensor 48 is turned on, the belt drive motor 22 is turned off. When the belt home sensor 48 is turned off and the tray discharge sensor 205 is turned on,
It is determined that the discharge is defective, and a signal is sent to the copying machine to remove the bundle of recording sheets on the staple tray. After the recording paper bundle is removed, the belt drive motor 22 is turned on to operate the discharge belt 17, and the belt home sensor 4
When 8 is turned on, the belt drive motor 22 is turned off.

At the time of copying and at the end of copying,
When the last sheet of the copy set is discharged onto the staple tray and the stapler S performs the binding operation of the bundle of recording sheets, the one-rotation sensor 210 is turned on to confirm that the stapling has been performed normally. Thereafter, the belt drive motor 22 is turned on, the discharge belt 17 is operated, the stapled recording paper bundle is discharged onto the discharge tray 53, and when the belt home sensor 48 is turned on, the belt drive motor 22 is turned off. Such an operation is repeated for the number of copies.

In the shift tray system among the transport systems,
When the copying machine body starts copying, a finish start signal is transmitted. When the signal is received, the conveying motor 220 is turned on and the low speed operation is performed at the same speed as the body line speed. When the recording paper is discharged from the main body and the entrance sensor SN1 is turned on, a timer is set to monitor whether the recording paper passes through the entrance sensor SN1 within a predetermined time and the jam is detected. The trailing edge of the recording paper passes through the entrance sensor SN1 and enters the entrance sensor S.
When N1 is turned off, the transport motor 220 is switched to high-speed operation, and the transport speed is increased. Further, a timer is set to monitor whether the leading end of the recording paper turns on the paper discharge sensor SN2 within a predetermined time, and jam detection is performed. When a predetermined time has elapsed after passing through the entrance sensor SN1, the transport motor 220 is returned to the low-speed operation, and is ready for the next recording paper to be carried in. Paper ejection sensor SN
When 2 is turned on by the recording paper, a timer is set, and it is monitored whether or not the recording paper passes within a predetermined time to detect a jam.

By repeating such an operation, in the case of the shift tray mode, when the shift signal is received, the last sheet of the copy set is discharged by the sheet discharge sensor SN2.
After a lapse of a predetermined time after passing through, the signal of shift OK is output, and the timing at which the shift operation is performed is measured. When the final recording paper is discharged from the main body, a finish stop signal is transmitted. When the signal is received, when a predetermined time has elapsed after the final recording paper has passed the paper discharge sensor SN2, the transport motor 220 is output. Is turned off.

Next, in the staple tray system, when the copying machine body starts copying, a finish start signal is transmitted. When the signal is received, the transport motor 220 is turned on and the low speed operation is performed. It is performed at the same speed as the main body linear speed. When the recording paper is discharged from the main body and the entrance sensor SN1 is turned on, the switching solenoid 230 and the lower conveyance motor 226 are turned on at a low speed operation, a timer is set, and whether the recording paper passes through the entrance sensor SN1 within a predetermined time. Is monitored to detect a jam. The trailing edge of the recording paper is the entrance sensor SN1
, The entrance sensor SN1 is turned off, and after a lapse of a predetermined time, the lower transport motor 226 is switched to high-speed operation to increase the transport speed. Further, a timer is set to monitor whether the leading end of the recording paper turns on the lower paper discharge sensor 50 within a predetermined time, and jam detection is performed. When a predetermined time has elapsed after the trailing edge of the recording paper has passed the entrance sensor SN1, the switching solenoid 230 is turned off. When the lower sheet discharge sensor 50 is turned on by the recording sheet, a timer is set, and it is monitored whether or not the recording sheet passes within a predetermined time to detect a jam. When a predetermined time has elapsed after the recording paper has passed the lower paper discharge sensor 50, the lower transport motor 226 is switched to low speed operation.

When a staple signal is received by repeating such an operation, a predetermined time elapses after the last sheet of the copy set has passed through the lower sheet ejection sensor 50, a sheet alignment operation is performed by a jogger fluence, and then staples are performed. The timing at which the operation is performed is measured. When the final recording paper is ejected from the main body, a finish stop signal is transmitted. When the signal is received, when a predetermined time has elapsed after the final recording paper has passed the paper ejection sensor 50, the transport motor is stopped. 220 and the lower transport motor 226 are turned off.

Further, as shown in FIG. 1, two timing pulleys 261 and 262 are mounted on a spindle of an inlet roller 260 for feeding the recording paper sent from the copying machine main body to the above-mentioned finisher. ing. Each of these timing pulleys 261 and 26
The two one-way clutches 26 are locked in one direction via one-way clutches 263 and 264 so as to be rotatable in the other direction.
The rotation allowable directions of 3 and 264 are set to be opposite to each other. Further, timing belts 265 and 266 are wound around the timing pulleys 261 and 262, respectively, and one timing belt 265 is wound around a timing pulley 267 fixed to the output shaft of the transport motor 220. At the same time, the other timing belt 266 is wound around a timing pulley 268 fixed to the output shaft of the lower transport motor 226.

When one of the shift tray system mode and the staple tray system mode is selected by the operation unit of the copying machine and the copy is started, the drive motor corresponding to the selected shift tray system and staple tray system is operated. Is turned on after a predetermined time.

First, when the shift tray system is selected, the rotational force of the transport motor 220 is transmitted to the timing pulley 261 via the timing belt 265, and the rotational force of the timing pulley 261 is further transmitted to the one-way clutch 26.
3 to the inlet roller 260, whereby a transport operation corresponding to the shift tray system is performed. At this time, the lower conveying motor 226 is in the off state, and the timing pulley 262 is put in the idling state by the rotation permitting action of the one-way clutch 264.

On the other hand, when the staple tray system is selected, the rotational force of the lower transport motor 226 is
, And the rotational force of the timing pulley 262 is transmitted to the inlet roller 260 via the one-way clutch 264, so that the conveying operation corresponding to the staple tray system is performed. I have. At this time, the transport motor 220 is in the off state, and the timing pulley 261 is put in the idling state by the rotation permitting action of the one-way clutch 263.

When a jam occurs due to a conveyance failure, the above-described conveyance path switching solenoid 230 is turned off, the lower conveyance motor 226 is turned off, and the conveyance motor 220 is turned on. Is discharged toward the discharge tray 107.

Further, as shown in FIG. 17, the CPU of the copying machine and the CPU of the finisher are connected by an optical fiber.

In the shift tray section of the finisher, a transport motor 1002 is connected to the CPU 1000 via a servo control circuit 1001, and an up / down motor 1004 is connected via a forward / reverse driver circuit 1003. Reverse driver circuit 1
The shift motor 1006 is connected via 005. Further, signals from various sensors and various switches 1007 are input to the CPU 1000.

Further, the CPU 1000 is connected to the staple section via an interface I / O. A staple unit 1008 is connected to the interface I / O, and the transport motor 1 is connected via a servo control circuit 1009.
011 is connected, a discharge motor 1013 is connected via a servo control circuit 1012, a jogger motor 1015 is connected via a stepping control motor control circuit 1014, and a stapler moving motor is connected via a stepping control motor control circuit 1016. 10
17 are connected. Further, the interface I / O includes various sensors and various switches 101.
8 is input.

[0061]

In any of the above-described conventional image forming post-processing apparatuses, the discharge tray is set so that the uppermost position of the sheets stacked on the discharge tray 107 coincides with a predetermined height. The sheet is stacked on the discharge tray 107 while the sheet 107 is being moved up and down. However, when the stacking of the sheets onto the discharge tray 107 starts,
The stacking operation of the sheets is started without confirming whether the sheets are left on the discharge tray 107.

FIGS. 18 to 20 are explanatory views showing the stacking state of the conventional sheet stacking apparatus. When the stacking operation is started with sheets remaining on the discharging tray, as shown in FIG. With the relatively small size paper RP remaining on the output tray 107,
When the relatively large size paper P is discharged upward, the paper P is likely to jump out of the discharge stack 107 or to be misaligned. In particular, when a large amount of the paper RP is left, the paper P jumps out and alignment failure becomes remarkable, and in the worst case, the discharged paper P may fall from the discharge tray 107.

As shown in FIG. 19 or FIG. 20, when a large amount of paper P is discharged onto the discharge tray 107, curling and waving are increased, and misalignment often occurs.

The present invention has been made in view of the current situation of this type of paper stack as described above, and an object thereof is to provide a paper stack apparatus which eliminates a stack defect caused by remaining paper in a discharge tray, and a paper stacking apparatus. It is an object of the present invention to provide a method of stacking sheets on a discharge tray without causing a stack defect due to remaining.

[0065]

SUMMARY OF THE INVENTION The object of the present invention is to provide a paper discharge means for discharging paper, a discharge tray for stacking the paper discharged by the paper discharge means, and a paper tray stacked on the discharge tray. The highest paper height or the
A first detecting means for detecting the upper surface height of the output tray, before Symbol
A second stacking means for detecting a predetermined height of the discharge tray in a sheet stacking apparatus having a tray elevating means for adjusting the height of the discharge tray so that the height coincides with a preset position. If, have accompanied the home position Chillon return operation of the discharge tray, said second detection means detects
If the first detecting means detects the state before the
It is determined that there is paper on the output tray, and the second detecting means detects the paper.
After the notification, when the first detection means detects,
Determining means for determining a paper-free onto the discharge tray, when a sheet perforated by the determined hand <br/> stage is achieved by taking the first means and a warning means for issuing a warning signal.

The object of the present invention is to provide a paper discharge means for discharging paper, a discharge tray for stacking the paper discharged by the paper discharge means, and a highest paper height of the paper stacked on the discharge tray. Or the top height of the discharge tray
Detecting a first detection means, so as to match the prior SL predetermined position height, the tray lifting means for adjusting the height of the discharge tray, the predetermined height of the discharge tray for detecting a is A sheet stacking device having a second detecting means for detecting the position of the discharge tray and returning to the first position after the second detecting means detects the home position of the discharge tray .
Detecting means only when the detected, it is achieved by taking the second means for Sutatsuku the paper onto the discharge tray.

[0067]

According to the first means, when the discharge of the paper is started, the determination means determines whether or not the paper remains on the discharge tray. If the paper remains in the discharge tray, an alarm is issued by the alarm means. Is performed. Therefore, when the alarm means issues an alarm, if the remaining paper is removed from the discharge tray and discharge is started, the discharge can be performed without jumping out of the paper onto the discharge tray or alignment failure.

By the second means, at the start of the stacking of the sheets, it is determined whether or not there is a sheet on the discharge tray, and it is confirmed that the sheet is not on the discharge tray. Can be discharged without jumping out or misalignment.

[0069]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 21 shows the overall structure of the finisher.

The finisher is attached to the side of the image forming apparatus 1, and the transport path A and the staples for guiding the copy (recording) paper discharged from the image forming apparatus 1 directly to the discharge tray 300 by the switching claw 105. A discharge tray 300 for stacking both non-stapled copy paper and staple-bound copy paper is arranged at the most downstream side of the conveyance path B for binding.

Reference numeral 101 denotes a transport roller for receiving the copy paper discharged from the image forming apparatus 1. An entrance sensor SN1 is provided immediately before the transport roller, and the leading and trailing ends of the transported recording paper are detected. It is like that. Downstream of the transport roller 101, a switching claw 105 is provided, and the transport direction is controlled by a solenoid and a spring (not shown) in either of the transport section I for stapling and the staple section II which does not perform stapling. Changes can be made.

The transport unit I for sorting and stacking is provided with a plurality of transport rollers 301 and 302 and driven rollers 303 and 304 driven by the rollers, and directly discharges the copy paper discharged from the image forming apparatus 1 to a discharge tray. Lead to 300.

Further, a conveyance path B for stapling
Also, a plurality of transport rollers 305 and 306 and driven rollers 307 and 308 are provided to guide the copy paper to the staple binding unit of the staple unit II.

FIGS. 22A and 22B are a front view and a side view schematically showing a staple binding unit. The staple unit includes a stapler 309 movable in a direction perpendicular to the paper surface according to the paper size, a brush roller 311 for moving the trailing end of the discharged paper to the guide plate 310, and a direction perpendicular to the transport direction. A pair of joga fluences 312 for aligning, a beating roller 313 for bringing the discharged paper to the guide plate 310, a discharge belt 314 for discharging the staple-bound copy to the discharge tray 300, and fixed to the discharge belt 314. It is composed of the discharged paper nail 315 and the like. The front beating roller 313 can be moved to a position shown by a broken line, and is moved and rotated every time the paper is discharged to move toward the guide plate 310.

FIG. 23 is an enlarged view of the discharge section.

At the discharge port, there is a discharge roller 316 for discharging both the non-stapled copy paper and the stapled copy paper to the discharge tray 300.
A sponge roller 317 (hereinafter, referred to as a "roller") is disposed at a lower portion thereof, and the copy paper dropped on the discharge tray 300 is abutted against the abutting guide plate 318 by the rotation thereof, whereby the copy paper is moved. The rear ends are aligned. The discharge tray 300 can be moved in the vertical direction by a vertical guide roller 319, and is driven by a drive mechanism (not shown). The discharge tray 300 can also be moved by a shift guide roller 320 in a direction perpendicular to the copy discharge direction, and the shift operation is also performed by a drive mechanism (not shown). Here, the approach roller 317 is provided with an upper surface detection lever 321 and a sensor SN8 for detecting the upper surface of the copy paper ejected in conjunction with this.
The discharge tray 3 is arranged so that the upper surface of the discharged stacked copy paper is always at a fixed position with respect to the discharge roller 316.
The height of 00 is adjusted. Further, the paper discharge driven roller 32
3 is normally in a position in contact with the paper discharge roller 316, but if necessary, the paper discharge guide plate
Along with 22, a drive mechanism (not shown) can rotate to a position indicated by a dashed line.

Next, the operation of the finisher will be described.

As an operation, a sort / discharge operation is performed in which copy sheets are discharged to the discharge tray 300 one by one without performing stapling.
The mode is divided into a stack mode and a staple mode in which the sheets are stapled and then discharged.

In the sort / stack mode, the switching claw 105 is located at the position indicated by the broken line, and the copy sheet discharged from the image forming apparatus 1 is sent to the sort / stack transport path A, and is discharged by the transport rollers 301 and 302. Sent to At this time, the paper ejection driven roller is always the paper ejection roller 3
The copy paper is discharged to the discharge tray 300 by contacting the print paper 16 with its own weight or under a pressure by a spring or the like. After the trailing edge of the copy paper is discharged from the paper discharge roller 316, the copy paper is abutted against the guide plate 318 by the rotation of the approach roller 317, and the trailing edge of the copy is aligned and stacked. The discharged copy papers are sequentially discharged by a predetermined number to the paper discharge tray 300, and are stacked so that the upper surface of the stacked copy paper is always at a fixed position by detecting the upper surface thereof by the sensor SN8. . If necessary, the discharge tray 300 performs a shift operation in a direction orthogonal to the copy discharge direction to sort paper.

In the staple mode, the switching claw 10
Reference numeral 5 denotes a position indicated by a solid line in FIG. 21, and the copy sheet discharged from the image forming apparatus 1 is guided to the staple transport path B and transported to the staple unit. A predetermined aligning operation is performed in the staple unit, and a staple binding operation is performed. Next, the paper is conveyed toward the paper discharge roller 316 by the rotation of the paper discharge belt 314 stretched along the paper discharge direction b and the paper discharge claw 315 fixed thereto. At this time, the paper discharge driven roller 323 has moved to the position indicated by the dashed line in FIG. 23 and is at a position separated from the paper discharge roller 316. In this state, the bound copy paper passes between the rollers 316 and 323, and the trailing end thereof
Before passing through the roller 16, the driven roller 323 and the guide plate 322 move from the separated position to a position where the copy sheet is pressed, and discharge the copy sheet. Note that this timing is detected by the sensor SN7. After the stapled copy paper is ejected, the copy paper is hit against the guide plate 318 by its own weight and the rotation of the approach roller 317, and the rear ends of the copy paper are aligned and stacked. The bundle of discharged copy sheets is sequentially discharged to the discharge tray 300 by a predetermined number of copies, and is stacked so that the upper surface of the copy sheets is always at a fixed position, as in the sort stack mode.

FIGS. 24 and 25 show the operating state of the detection lever. The detection lever 321 is connected to the discharge roller 316.
And detects the upper surface of the copy paper discharged by the discharge driven roller 323 and detects the home position of the tray 300 when there is no copy paper in the tray 300. It rotates about the axis and detects it with the shielded sensor SN4. Further, the detection lever 321 is in a state of being constantly pressed against the tray 300 by the weight of the approach roller 317. SN5 is a shield type sensor, and a tray 3 is attached by a filer 324 attached to a side plate of the tray 300.
The absolute distance on the loading surface of 00 is detected. The sensor SN9 is set so that the sheet loading surface of the tray 300 is detected before the home position is detected by the sensor SN8.

Next, the home position return operation will be described.

First, the home position of the discharge tray 300 is detected as follows. Normally, at the start of copying, since predetermined processing has been completed from the discharge tray 300 and the discharged paper has been removed, the sensor SN8 is not blocked by the detection lever 321 and the tray 3
00 rises upward in the plane of the paper, the sensor SN9 is shielded, and then the sensor SN8 is shielded. Next, when the sensor SN8 is shielded by the detection lever 321, the ascent stops once, and then the tray 300 is lowered until the sensor SN8 is no longer shielded, thereby setting the home position.

Next, the home position return operation when the copy sheet remains on the tray 300 as shown in FIG. 25 will be described. At the start of copying, tray 3
00 rises upwards on the paper surface, and before the sensor SN9 detects the filler 324, the sensor SN8 detects the upper surface of the copy paper, and detects that the copy paper remains on the tray 300. At this time, a signal for stopping the next copy operation is sent to the image forming apparatus, and a message to remove the copy sheet on the tray 300 is displayed on the display of the image forming apparatus. After the operator removes the copy paper, the operation is repeated again, and the tray 300 is removed.
If it is determined that there is no paper above, normal copying is started.

Next, when the copy paper is discharged onto the discharge tray 300, the detection lever 321 rotates by an amount corresponding to the thickness of the paper, and the sensor SN8 is shielded. The change of this signal lowers the discharge tray 300. Output tray 3
When 00 falls, the shielding of the sensor SN8 is released, and the lowering of the tray 300 stops. The above operation is repeated a predetermined number of times, the height of the tray 300 is adjusted, and the upper surface of the discharged copy sheet is always kept at a fixed position with respect to the discharge roller 316. Note that the sensor SN9 is always
If the sensor SN8 does not detect the upper surface of the tray 300 in a state where the tray 300 is detected, it is determined that paper remains on the tray 300, the next copy operation is prohibited, and the fact is displayed on the display. And inform the operator.

FIG. 26 is a flowchart showing the operation described above.

The other components which are not particularly described are the same as those of the above-described conventional example.

According to the above-described embodiment, the paper discharge roller 316 for discharging the paper, the discharge tray 300 for stacking the paper discharged by the paper discharge roller 316, and the paper stacked on the discharge tray 300 or its upper part. The detection lever 321 and the sensor SN8 for detecting the height of the uppermost sheet surface of the sheet are driven in response to a detection signal from the detection means, and the height of the discharge tray 300 is displaced to thereby move the uppermost sheet on the tray 300. In a paper stacker provided with a tray elevating device that always keeps the upper sheet at a constant height, a filer 3 for detecting the absolute position of the discharge tray 300 itself.
24 and a sensor SN9 are provided to determine the presence or absence of a copy sheet on the tray 300 together with the sensor SN8 in accordance with the home position return operation at the start of copying. If there is a copy sheet, the operator is informed of the fact. Means to notify the user that the copy sheet has been removed from the tray 300 and then start copying, thereby improving the stackability of the sheet and improving the operability.

[0090]

According to the first aspect of the present invention, a discharge tray is provided.
With the home position return operation, the second detection means
If the first detection means detects before the detection,
It is determined that there is paper on the ray, and the second detection means has detected
Later, when the first detecting means detects, the
Determining means for determining that there is no paper;
And warning means for issuing a warning signal.
Because, by notifying the operator, always remaining sheets on the discharge tray is removed during the paper Sutatsuku Runode, or pop out paper at Yotsute Sutatsuku the remaining paper, to completely prevent or summer and aligned defective It is possible to provide a paper stacking device that performs a stacking operation.

According to the second aspect of the present invention, the discharge tray
In response to the home position return operation, the second detecting means detects
After that, only when the first detection means detects,
Paper on the output tray to stack the paper on the
Since stacking is performed in a state where there is no stacking, stacking without jumping out of paper or alignment failure can be performed .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a conventional transport drive system.

FIG. 2 is an explanatory diagram showing the entire configuration of the related art.

FIG. 3 is a perspective view of a conventional discharge tray.

FIG. 4 is an explanatory diagram showing a tray engaged state in a conventional tray shift rocking mechanism.

FIG. 5 is an explanatory plan view showing a drive system of a conventional tray shift rocking mechanism.

FIG. 6 is a perspective view showing a drive system of a conventional tray shift rocking mechanism.

FIG. 7 is a perspective view of a conventional paper ejection press mechanism.

FIG. 8 is an explanatory side view of a conventional discharge tray raising / lowering mechanism.

FIG. 9 is a perspective view of a conventional discharge tray raising / lowering mechanism.

FIG. 10 is an explanatory diagram of a conventional sheet discharging operation.

FIG. 11 is an explanatory diagram showing a configuration of a conventional staple unit.

FIG. 12 is an explanatory bottom view showing the configuration of a conventional staple unit.

FIG. 13 is an explanatory view showing a conventional stapler mounting structure.

FIG. 14 is a perspective view of a conventional discharging device.

FIG. 15 is a sectional view taken along line BB of FIG. 11;

FIG. 16 is an explanatory side view of a conventional staple discharge unit.

FIG. 17 is a block diagram showing a configuration of a conventional control device.

FIG. 18 is an explanatory view showing a stack state of a conventional paper stacking apparatus.

FIG. 19 is an explanatory diagram showing a stacking state of a conventional paper stacking device.

FIG. 20 is an explanatory diagram showing a stacking state of a conventional paper stacking device.

FIG. 21 is an explanatory diagram showing an overall configuration of a finisher to which the present invention is applied.

FIG. 22 is an explanatory view showing a staple binding unit of the present invention.

FIG. 23 is an explanatory diagram showing an enlarged discharge section of the present invention.

FIG. 24 is an explanatory diagram showing an operation state of the detection lever of the present invention.

FIG. 25 is an explanatory diagram showing an operation state of the detection lever of the present invention.

FIG. 26 is a flowchart showing a home position return operation of the present invention.

[Explanation of symbols]

 1 Image Forming Apparatus 300 Discharge Tray 316 Discharge Roller 321 Detection Lever 324 Filler SN8, SN9 Sensor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B65H 43/02 B65H 7/02 B65H 31/00 G03G 15/00 530

Claims (2)

(57) [Claims] 1. A sheet discharging means for discharging a sheet, a discharging tray for stacking the sheets discharged by the sheet discharging means, and a highest sheet height of the sheets stacked on the discharging tray or a first detecting means for detecting the upper surface height of the discharge tray, to match the prior SL predetermined position height, paper Sutatsuku comprising a tray lifting means for adjusting the height of the discharge tray in the device, a second detecting means for detecting a predetermined height of the discharge tray, had accompanied the home position Chillon return operation of the discharge tray, before
Before the second detecting means detects, the first detecting means
When it is detected, it is determined that there is paper on the discharge tray,
After the detection by the second detection means, the first detection means
A sheet stacking device , comprising: a judgment unit for judging that there is no sheet on the discharge tray when is detected; and a warning unit for issuing a warning signal when a sheet is present by the judgment unit. 2. A paper discharge means for discharging paper, a discharge tray for stacking the paper discharged by the paper discharge means, and a highest paper height of the paper stacked on the discharge tray or a first detecting means for detecting the upper surface height of the discharge tray, to match the prior SL predetermined position height, the tray lifting means for adjusting the height of the discharge tray, said discharge tray A sheet stacking device including a second detecting means for detecting a predetermined height, wherein the first detecting means detects the first height after the second detecting means detects the home position of the discharge tray in response to the home position return operation. only when the unit detects the paper Sutatsuku method characterized by Sutatsuku the paper onto the discharge tray.