JP2007076912A - Sheet post-processing device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet post-processing device capable of reducing variations in the stop position of sheets from the start to the end of stacking compared with a device shown in a patent publication No. 2002-265117 if the sheets are of the same size, the same thickness and the same kind. <P>SOLUTION: The sheets P are stacked sheet by sheet on a processing tray 130 from a first discharge roller pair 7. A control part 60 controls the rotating speed of a driving motor 206 to change the conveying speed of the first discharge roller pair 7 during conveyance to thereby set the discharge speed corresponding to the condition of the stacking surface. When the sheets have not been stacked on a stacking tray 200, the discharge speed is made lower than the case of being finished with stacking. After the stacked number of sheets on the processing tray 130 reaches the predetermined number of sheets, the discharge speed is made higher than before. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile machine, a multifunction machine, a sheet post-processing apparatus that post-processes a sheet discharged from another office machine, and an image forming apparatus incorporating / connecting the sheet post-processing apparatus. Relates to the device.

  After a sheet is received from an image forming apparatus such as a copier, printer, facsimile, etc., and subjected to various processes such as alignment, sorting, stacking, folding, envelope filling, binding processing, bookbinding, punching, inspection, processing, etc. Processing equipment has been put into practical use. In addition, in an image forming apparatus such as a copying machine, such a sheet post-processing apparatus is built in or connected as a purchase option.

  A sheet post-processing apparatus shown in Patent Document 1 is an apparatus that accepts sheets from a copying machine and performs staple binding processing collectively for each predetermined number of sheets, and includes a first sheet stacking member on which a predetermined number of sheets are stacked, A first discharge member that discharges a sheet in a direction along the first sheet stacking member and stacks the sheet on the first sheet stacking member, and a second discharge member that discharges the sheet bundle that has been stapled on the first sheet stacking member A second sheet stacking member arranged to support a part of the sheet discharged to the first sheet stacking member and stacking the sheet bundle discharged by the second discharge member, and discharged to the first sheet stacking member And an alignment member (paddle, knurled belt) that moves in a direction opposite to the discharging direction in contact with the formed sheet.

  Further, the sheet post-processing apparatus disclosed in Patent Document 1 refers to the size and thickness of a sheet from a copying machine in order to reduce variation in the stop position of the sheet discharged to the first sheet stacking member by the first discharge member. Type information is acquired, and the discharge speed of the first discharge member is set according to the type information. A smaller discharge speed is set for a small sheet than for a large sheet, and a lower discharge speed is set for a thick sheet than for a thin sheet.

JP 2002-265117 A

  The sheet post-processing apparatus disclosed in Patent Document 1 can reduce the variation in the stop position due to the type difference of the sheets discharged to the first sheet stacking member. However, even with the same size, the same thickness, and the same type of sheet, it has been found that the stop position varies greatly depending on the status of the stacking surface during ejection.

  That is, even when the discharge speed is the same, if the friction force between the sheet stacking surface and the sheet is small, the braking force of the sheet is small, and the stop position of the sheet is shifted in the discharge direction compared to when the friction force is large. End up. If the stop position of the sheet discharged to the first sheet stacking member is shifted, the movement of the sheet using the alignment member cannot be reproduced uniformly, and the sheet stops outside the range that can be aligned by the alignment member. As a result, as disclosed in Patent Document 1, the alignment state of the sheets is disturbed, and the necessary post-processing cannot be normally executed.

  Here, since the thin sheet hangs down and contacts the first sheet stacking member at an early stage, it can be said that the frictional force is larger than that of the thick sheet, and a large sheet also hangs down and easily contacts the first sheet stacking member. It can be said that the frictional force is larger than the small size sheet. However, it is impossible to accurately estimate the frictional force between the stacking surface and the sheet only with sheet information such as size, thickness, and type.

  The present invention relates to a sheet post-processing apparatus capable of making the variation in the stop position of a sheet from the start to the end of stacking smaller than that of the sheet post-processing apparatus of Patent Document 1 if the sheets have the same size, the same thickness, and the same type. The purpose is to provide.

  A sheet post-processing apparatus according to a first invention includes a sheet stacking member on which sheets are stacked, and a discharge member that discharges the sheet in a direction along the sheet stacking member and stacks the sheet on the sheet stacking member. In the apparatus, the discharge control for controlling the discharge speed of the sheet by driving the discharge member, and setting the discharge speed larger than before when the number of sheets discharged to the sheet stacking member exceeds a predetermined number Device.

  A sheet post-processing apparatus according to a second aspect of the invention includes a first sheet stacking member on which sheets are stacked, and a sheet disposed on the upstream side of the first sheet stacking member and temporarily loading the sheets stacked on the first sheet stacking member. And a discharge member for discharging the sheet in a direction along the second sheet stacking member, and a portion on the leading end side of the sheet stacked on the second sheet stacking member In the sheet post-processing apparatus supported by the first sheet stacking member, the discharge member is driven to control the discharge speed of the sheet, and when the sheet is stacked on the first sheet stacking member, And a discharge control device that sets the discharge speed to be larger than that in the case of no loading.

  In the sheet post-processing apparatus according to the first aspect of the invention, when a number of sheets exceeding a predetermined value are stacked on the sheet stacking member, the stacking surface becomes high due to the thickness of the sheets stacked so far, and the discharged sheets are discharged. Since it contacts the loading surface earlier, the discharge speed is increased more than before, the increase in the frictional force due to the extension of the contact time is overcome, and the sheet is made to reach a little far in the discharge direction and stopped.

  In the sheet post-processing apparatus according to the second aspect of the present invention, if a sheet is present on the second sheet stacking member, the frictional force at the front end portion of the sheet is larger than when no sheet is present. Overcome the increase in force, let the sheet reach a little far in the discharge direction and stop.

  Therefore, the shift of the stop position due to the change in the frictional force between the stacking surface and the sheet is offset, and the variation in the stop position can be made smaller than when the discharge speed is not changed. In other words, since the discharge speed is changed according to the state of the stacking surface at the time of discharge, the variation in the sheet submission position is small compared to the apparatus of Patent Document 1 that ignores the state of the stacking surface at the time of discharge. Alignment accuracy is increased and post-processing defects are reduced.

  FIG. 1 is an explanatory diagram of a configuration of an image forming apparatus connected to a sheet post-processing apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a configuration of a processing unit in the sheet post-processing apparatus, and FIG. 4 is a rear view of the processing tray, FIG. 5 is a flowchart of discharge speed control, FIG. 6 is an explanatory view of sheet discharge when the stack tray is not stacked, and FIG. 7 is a sheet with the stack tray stacked. FIG. 8 is an explanatory diagram of sheet discharge when a large number of processing trays are stacked, and FIG. 9 is an explanatory diagram of sheet discharge when a processing tray is stacked with a small number of sheets.

  The sheet post-processing apparatus 1 of the present embodiment includes, for example, a stack tray 200 that is a sheet stacking member or a first sheet stacking member, a processing tray 130 that is a second sheet stacking member, and a first discharge roller that is a discharge member, for example. For example, the control unit 60 and the motor 206, which are discharge control devices, are provided.

  As shown in FIG. 1, a sheet post-processing apparatus 1 according to the present embodiment is a so-called “finisher” which is connected to the downstream side of an image forming apparatus (copier) 300 and is discharged from the image forming apparatus 300. The sheet received from the roller pair 302 is post-processed by the processing unit 129 and stacked on the stack trays 200 and 201.

  The entrance roller pair 2 of the sheet post-processing apparatus 1 receives the sheet P on which the image is formed by the image forming unit 301 of the image forming apparatus 300 from the discharge roller pair 302. The sheet P is conveyed from the inlet roller pair 2 to the buffer roller 5 through the first conveying roller pair 3 and the punch unit 50. The punch unit 50 can punch holes at the rear end of the sheet temporarily stopped during conveyance. The sheet detection sensor 31 is a switch sensor that detects the leading edge and the trailing edge of the received sheet P and reverses the output.

  The buffer roller 5 is a relatively large-diameter roller member that is activated / stopped at a predetermined timing, and can wind and hold the sheet P delivered from the first conveying roller pair 3 around the outer periphery thereof. Further, if the switching flapper 10 is positioned on the buffer roller 5 side, the sheet P can be sandwiched between the pressing rollers 12, 13 and 14 arranged along the outer periphery and conveyed to the conveyance path 22. .

  The buffer roller 5 is activated after a predetermined distance from the detection of the leading edge of the sheet P by the sheet detection sensor 31 in a state where the switching flapper 10 is positioned outside, and the sheet P is delivered. Stopped immediately after detecting the tip. Then, the subsequent sheet P is superposed on the buffer roller 5 in which the leading edge of the sheet P is positioned, and the leading edge is aligned and held together, and the switching flapper 10 is tilted to the buffer roller 5 side. After the first rotation, it is possible to send a stack of n stacked sheets together to the conveyance path 22.

  The bundle of sheets P passed through the transport path 22 is transported from the second transport roller pair 6 to the processing unit 129, and transferred from the first discharge roller pair 7 of the processing unit 129 to the second discharge roller pair 180, and the sheet The rear end side of the bundle of P falls to the processing tray 130. In this state, it is possible to reverse the second discharge roller pair 180 to push the bundle of sheets P into the innermost portion of the processing tray 130 and perform staple binding processing with the stapler 100.

  However, an example will be described below in which the sheet P is continuously discharged from the first discharge roller pair 7 to the processing tray 130 one by one with the second discharge roller pair 180 being separated.

  The stack trays 200 and 201 are supported so as to be movable up and down with respect to the housing structure of the sheet post-processing apparatus 1, and each has an independent drive mechanism (not shown) and moves up and down along the alignment wall 40. When the sheets P (or a bundle of sheets P) are stacked on the stack trays 200 and 201 through the second discharge roller pair 180, the stack trays 200 and 201 have their stack surfaces (the surface of the uppermost sheet P after one sheet is stacked). ) Is gradually lowered so as to reach a certain height position.

  However, when the second discharge roller pair 180 is separated and the sheets are stacked on the processing tray 130, the stacking surfaces of the stack trays 200 and 201 are positioned close to the processing tray 130 as shown in FIG. And the leading end portion of the sheet P discharged to the processing tray 130 is supported by the stacking surface.

  As shown in FIG. 2, the processing unit 129 has a paddle 160 disposed above the processing tray 130 and a knurled belt 190 disposed on the bottom side of the processing tray 130 as a conveying direction aligning unit. A side guide 140 is disposed on the processing tray 130 as direction alignment means.

  A plurality of paddles 160 are arranged in the width direction of the sheet P with two rod-shaped members formed of a flexible elastic body as one set. The paddle 160 is driven by the drive motor M160 and rotates once counterclockwise around the drive shaft 161 to contact the surface of the sheet P discharged to the processing tray 130. The sheet P is pulled back to the discharge side.

  The knurled belt 190 is a circular outer appearance and an easily deformable annular member in which a knurling for slip prevention is formed on the outer periphery. As shown in FIG. 6, a plurality of knurling belts 190 are arranged in the width direction of the sheet P at a height position in contact with the surface of the processing tray 130, and a common drive motor with the first discharge roller pair 7. It is driven by 206. The knurled belt 190 pulls the rear end of the sheet P transferred from the paddle 160 into the innermost part of the processing tray 130. The knurled belt 190 is looped between the discharge roller 7a of the first discharge roller pair 7 and the guide roller 191. When the sheet P is moved by the paddle 160, the guide roller 192 is operated to operate the guide roller 192. 191 is moved to the back side to release the contact with the sheets P stacked on the processing tray 130 so that the movement of the sheets P is not hindered.

  The first discharge roller pair 7 includes a discharge roller 7a driven by a drive motor 206 and a driven roller 7b on the driven side that is spring-biased toward the discharge roller 7a. The second discharge roller pair 180 is driven by a drive motor M180, and, as will be described later, the drive-side lower discharge roller 180a whose shaft position is fixed, and the shaft position that can be joined / separated from the lower discharge roller 180a. The upper discharge roller 180b is supported on the driven side.

  A discharge port 205 is formed in the alignment wall 40 at the height position of the second discharge roller pair 180. Inside the alignment wall 40, a snowboard shutter 202 supported so as to be movable to the discharge port 205 is disposed. The snooter shutter 202 is driven by a drive motor 206 that is common to the discharge roller 7 a and the knurled belt 190. When the drive motor 206 is rotated in the direction opposite to that at the time of discharging, the link 203 rotates upward about the rotating shaft 204 and the snow shutter 202 moves to the discharge port 205. The snooter shutter 202 moves to the discharge port 205 to form a comb-like lid, and the stack tray 200 (201) moves when the stack tray 200 (201) moves along the alignment wall and passes through the discharge port 205. So that the sheet P stacked on the sheet does not fall or get caught in the discharge port 205.

  The drive motor M150, M160, M180, 206 and the traction actuator 192 are controlled by the control unit 60 in the rotation direction, rotation speed, and rotation amount.

  As shown in FIG. 3, the upper discharge roller 180 b of the second discharge roller pair 180 is fixed to the swing guide 150. The swing guide 150 is rotated upward / downward by rotating the rotary cam 152 with the drive motor 150 in a state of being biased downward by a torsion spring (not shown), and the upper discharge roller 180b and the lower discharge roller 180a. Are separated / joined.

  A rear end stopper 131 that is fixed to the processing tray 130 is disposed at the innermost portion of the processing tray 130 of the second discharge roller pair 180. The rear end stopper 131 is rotated to raise the support surface 131a, and the support surface 131a abuts against the rear end of the sheet P moving to the back side on the processing tray 130 to align the sheet P.

  An inner sheet guide 130 c is disposed on the inner side of the alignment surface of the knurled belt 190. The inner seat guide 130c is a fixed guide member disposed at an interval of the knurled belt 190. When the guide roller 191 is pulled to the back side by the pulling actuator 192 shown in FIG. The contact between the sheet P and the knurled belt 190 is prevented.

  The side aligning mechanism 140 moves the side guides 141 and 142 in the width direction of the sheet P to align the sheet P discharged to the processing tray 130 in the width direction. A driving mechanism for the side surface alignment mechanism 140 is disposed on the lower surface side of the processing tray 130. FIG. 4 is a view of this drive mechanism as viewed from the direction of arrow C in FIG.

  As shown in FIG. 4, the side guide 141 is supported so as to be movable along the through groove 130a of the processing tray 130. The guide surface 141a is erected on the stacking surface of the processing tray 130, and the rack gear on the lower surface side is passed through the through groove 130a. 141b. The pinion gear 143 fixed to the processing tray 130 meshes with the rack gear 141b and is driven by the drive motor M141 to move the side guide 141 in the width direction of the processing tray 130. Similarly, the side guide 142 is supported so as to be movable along the through groove 130b of the processing tray 130. The guide surface 142a is erected on the stacking surface of the processing tray 130, and is connected to the lower rack gear 142b through the through groove 130a. ing. The pinion gear 144 fixed to the processing tray 130 meshes with the rack gear 142b and is driven by the drive motor M142 to move the side guide 142 in the width direction of the processing tray 130.

  In the sheet post-processing apparatus 1 configured as described above, when the operator sets the discharge mode of the image forming apparatus (copier) 300 to non-sort, the control unit 60 shown in FIG. 150 is rotated downward to bring the lower discharge roller 180a and the upper discharge roller 180b into contact with each other, and the inlet roller pair 2, the first conveyance roller pair 3, the buffer roller 5, the second conveyance roller pair 6, and the like shown in FIG. The first discharge roller pair 7 and the second discharge roller pair 180 are rotated at the same conveyance speed, and the sheets P are simply conveyed to the downstream side one by one and discharged onto the stack tray 200 one by one.

  At this time, the side guides 141 and 142 shown in FIG. 4 move to the inner position in the width direction to prevent the sheet P from falling to the processing tray 130, and at the same time, the knurled belt 190 is moved back by the traction actuator 192. To be separated from the processing tray 130.

  On the other hand, when the operator sets the discharge mode of the image forming apparatus 300 to staple sorting, the control unit 60 shown in FIG. 2 rotates the swing guide 150 shown in FIG. The discharge roller 180b is separated and the inlet roller pair 2, the first transport roller pair 3, the buffer roller 5, and the second transport roller pair 6 shown in FIG. 1 are rotated at the same transport speed V0, and the sheet P is moved downstream by one sheet. To the first discharge roller pair 7 and discharged one by one to the processing tray 130.

  The sheet P that has dropped onto the processing tray 130 starts to slide down the inclination of the stacking surface due to its own weight. Then, the paddle 160 that rotates once every discharge pulls the sheet P back to the contact point between the knurled belt 190 and the aligned sheet, and then the knurled belt 190 and the paddle 160 work together to move the sheet P to the back side and support it. It strikes against the surface 131a.

  At this time, the knurled belt 190 is released from the pulling of the pulling actuator 192, contacts the processing tray 130, and circulates in conjunction with the driven roller 7b as shown in FIG. After that, when the knurled belt 190 is pulled by the pulling actuator 192 to release the contact with the sheet P, the side guides 141 and 142 shown in FIG. 4 waiting at the outer position in the width direction are moved inward to a predetermined alignment position. By reciprocating, the side surfaces of the sheet P in the width direction are aligned.

  At this time, as described above, the stack tray 200 is raised to a position where the stacking surface is slightly below the processing tray 130 to support the leading edge of the sheet P, and even the long sheet P does not slip off the processing tray 130. I am doing so.

  By the way, when the first sheet P is discharged from the first discharge roller pair 7 to the processing tray, the stack tray 200 is not stacked as shown in FIG. 6 even if the conveyance speed of the first discharge roller pair 7 is the same. As shown in FIG. 7, since the frictional force at the front end of the sheet P is smaller than when the sheet is stacked on the stack tray 200, the sheet P slides far and pulls the sheet P to the knurled belt 190 by the paddle 160. There is a high possibility that the alignment in the transport direction will be disturbed because it cannot be returned. Therefore, the control unit 60 shown in FIG. 2 controls the drive motor 206 to change the conveyance speed of the first discharge roller pair 7 between the case where the stack tray 200 is not stacked and the case where the stack is advanced. In this case, a transport speed V1 lower than the transport speed V2 when the stacking is advanced is set.

  Further, as shown in FIG. 8, when the number of sheets P stacked on the processing tray 130 increases, the frictional distance until the discharged sheet P stops is increased, and the sheets P are stacked as shown in FIG. The sheet P is stopped earlier than when the number of sheets P is small, and the possibility that the rear end of the sheet P rides on the knurled belt 190 and is folded in two is increased. 2 controls the drive motor 206 so that the number of stacked processing trays 130 reaches, for example, a predetermined number of sheets A that can be determined by the type of sheet to be stacked, the thickness of the sheet, and the like. After that, the conveying speed V3 higher than the conveying speed V2 until reaching the first discharging roller pair 7 is set.

  As shown in FIG. 5, the control unit 60 counts the number of sheets P discharged to the processing tray 130 in step S11. In step S12, it is determined whether or not it is the first sheet P. If it is the first sheet, the process proceeds to step S13 to determine whether or not the stack tray 200 is not stacked. Proceed to set the transport speed V1.

  In step S12, if the second and subsequent sheets have been loaded and if loaded in step S13, the process proceeds to step S14 to determine whether or not the number of sheets discharged to the processing tray 130 has reached A. If it is less than A, step S16 is performed. Then, the conveyance speed V2 is set, but after reaching A, the process proceeds to step S17 to set the conveyance speed V3.

  In any case, when the first discharge roller pair 7 receives the sheet P at the conveyance speed V0 and escapes the restraint of the second conveyance roller pair 6, the conveyance speed V0 becomes the conveyance speed V1, V2, or V3. In this way, the conveyance state of the sheet P is not disturbed between the second conveyance roller pair 6 and the first discharge roller pair 7.

  As described above, according to the sheet post-processing apparatus 1 of this embodiment that controls the conveyance speed of the first discharge roller pair 7, the conveyance speed is higher when the sheets P are not stacked on the stack tray 200 than when the sheets P are stacked. Therefore, the difference between the sheet stop position in the unstacked state shown in FIG. 6 and the stop position in the stacked state shown in FIG. Even in the case of stacking, there is a high possibility that the sheet P can be reliably pulled back to the knurled belt 190 by the paddle 160 and can be normally aligned.

  Further, since the transport speed is increased after the stacking number N of the processing tray 130 reaches A, the stop position after the stacking number N shown in FIG. 8 reaches A and the stacking shown in FIG. The difference in the stop position before the number N reaches A becomes small, and even if the number N of sheets stacked exceeds A, the possibility that the sheet P leans excessively on the knurled belt 190 and is folded in two becomes low.

  In other words, in order to reliably perform the alignment operation of the sheet P in the processing tray 130, the trailing edge of the discharged sheet P falls to the processing tray 130 after passing through the nip point of the discharge roller pair 7, and is caused by the paddle 160. The amount of movement (jumping amount) in the conveyance direction until pulling is started is within a certain range, that is, the sheet P does not fly too much to be pulled back to the trailing edge stopper 131, and the sheet jump amount is insufficient. Thus, it is necessary that the knurled belt 190 is stable within a range that does not lean against the outer periphery.

  However, in the sheet post-processing apparatus disclosed in Patent Document 1, even when the stack tray 200 is not stacked, if the sheet P is of the same type, the discharge speed is the same as that when the stacking is advanced, and the stack is loaded on the processing tray 130. However, if the type of sheets P is the same, the discharge speed is the same as when the number of stacked sheets is small. Therefore, when the stack tray 200 is not stacked, the jump amount of the sheets P tends to be excessive, and the sheet P is placed on the processing tray 130. The amount of flight tends to be insufficient as the loading of the vehicle progresses.

  Therefore, when the stack tray 200 is not stacked, the discharge speed is decreased to reduce the jump amount of the sheet P, and when the stack is advanced to the processing tray 130, the discharge speed is increased to increase the jump amount.

  Therefore, even when the stack tray 200 is not loaded, it is easy to complete the alignment normally, and even if the stacking is advanced on the processing tray 130, the alignment failure is less likely to occur.

  Furthermore, in other words, the sheet post-processing apparatus 1 of the present embodiment changes the discharge speed to the processing tray 130 according to the number of sheets already stacked on the processing tray 130 and the presence or absence of sheets on the stack tray 200. P can be accurately discharged to the processing tray 130, and the alignment and stackability of the sheets P can be improved.

  In the sheet post-processing apparatus 1 of the present embodiment, when the stack end 200 is moved up and down by driving the circular endless knurled belt 190 that is a flexible elastic body and the slatted shutter 202 by the common drive motor 206. The drive motor 206 is operated in a direction to drive the first discharge roller pair 7 in the direction opposite to the conveyance direction to move the slat shutter 202 to the discharge port 205. At this time, the guide roller 191 is moved by the traction actuator 192. Since the knurl belt 190 is pulled away to the back side, the knurl belt 190 does not bend between the lower carry-out roller 7a and the guide roller 191 and does not become unstable in shape and posture. In addition, even when alignment by the knurling belt 190 is unnecessary, the pulling actuator 192 pulls the guide roller 191 so that the knurling belt 190 is retracted to the back side, so that the knurling belt 190 is reduced in wear and prevented from being damaged. it can. The normal knurled belt 190 can reliably process the sheet P and the sheet bundle for a long period of time, so that the sheet bundle can be reliably aligned, the occurrence of binding failure of the sheet bundle can be prevented, and the appearance of the stacked sheet bundle can be improved. Also gets better.

  Further, the image forming apparatus 300 including the sheet post-processing apparatus 1 according to the present embodiment does not waste the image-formed sheet by reducing the occurrence of sheet bundle binding failure by the sheet post-processing apparatus 1. Therefore, the image forming efficiency of the sheet can be increased.

  In the above description, the knurled belt 190 is retracted in synchronism with the alignment of the sheets P for all the sheets P discharged to the processing tray 130 one by one. Until the predetermined number is reached, the knurling belt 190 may not be retracted. In other words, during the period when the stacking height of the sheets P stacked on the processing tray 130 is low and the uppermost sheet P is not in contact with the knurled belt 190, the retreat operation is omitted and the knurled belt 190 is always in the protruding position. You can keep it.

  By the way, in the image forming apparatus 300, instead of externally connecting the sheet post-processing apparatus 1, an image forming unit 301 that forms an image on the sheet P and a process in which the sheet P on which an image is formed by the image forming unit 301 is stacked. The tray 130 and the first discharge roller pair 7 that discharges the sheet P in the direction along the processing tray 130 and stacks the sheet P on the processing tray 130 may be housed in the same housing for commercialization.

  In this case, since there is little need to provide the independent control unit 60, the control device 300 that controls the image forming unit 301 may control the discharge speed of the sheet P by driving the first discharge roller pair 7. Also in such an embodiment, when the number of sheets P discharged to the processing tray 130 exceeds a predetermined number, the same effect as in this embodiment can be obtained by setting the discharge speed higher than before.

  Further, even when the sheet post-processing apparatus 1 of another casing is connected to the downstream side of the image forming apparatus 300, the control by the control unit 60 described above may be performed by the control apparatus 310.

FIG. 3 is an explanatory diagram of a configuration of an image forming apparatus to which a sheet post-processing apparatus of the present embodiment is connected. It is explanatory drawing of a structure of the process part in a sheet | seat post-processing apparatus. It is a detailed explanatory view of a configuration of a processing unit. It is a rear view of a processing tray. It is a flowchart of discharge speed control. FIG. 10 is an explanatory diagram of sheet discharge when a stack tray is not stacked. FIG. 10 is an explanatory diagram of discharging a sheet on which a stack tray has been stacked. FIG. 10 is an explanatory diagram of sheet discharge when a plurality of processing trays are stacked. FIG. 10 is an explanatory diagram of sheet discharge when a processing tray is loaded with a small number of sheets.

Explanation of symbols

P sheet 1 sheet post-processing device 7 first discharge roller pair (discharge member)
7a discharge roller 7b driven roller 60 control unit (discharge control device)
100 Stapler 129 Processing unit (discharge control device)
130 Processing tray (second sheet stacking member)
131 Rear end stoppers 141, 142 Side guides 141a 142a Alignment surface 160 Paddle 180 Second discharge roller pair (discharge member)
180a Lower discharge roller 180b Upper discharge roller 190 Knurling belt 191 Guide roller 192 Traction actuator 200, 201 Stack tray (first sheet stacking member)
202 Snowboard shutter 205 Discharge port 206, M141, M142, M150, M160, M180 Drive motor (discharge control device)
300 Image Forming Apparatus 301 Image Forming Unit (Image Forming Unit)

Claims (5)

A sheet stacking member on which sheets are stacked;
A sheet post-processing apparatus having a discharge member that discharges the sheet in a direction along the sheet stacking member and stacks the sheet on the sheet stacking member;
A discharge control device for controlling the discharge speed of the sheet by driving the discharge member, and setting the discharge speed larger than before when the number of sheets discharged to the sheet stacking member exceeds a predetermined number; A sheet post-processing apparatus comprising: A first sheet stacking member on which sheets are stacked;
A second sheet stacking member that is disposed upstream of the first sheet stacking member and temporarily stacks the sheets stacked on the first sheet stacking member;
A discharge member that discharges the sheet in a direction along the second sheet stacking member,
In the sheet post-processing apparatus in which the first sheet stacking member supports a portion on the leading end side of the sheets stacked on the second sheet stacking member,
A discharge control that controls the discharge speed of the sheet by driving the discharge member, and sets the discharge speed larger when the sheet is stacked on the first sheet stacking member than when the sheet is not stacked. And a sheet post-processing apparatus.   3. The sheet post-processing according to claim 2, wherein when the number of sheets discharged to the second sheet stacking member exceeds a predetermined number, the discharge control device sets the discharge speed higher than before. apparatus. Image forming means for forming an image on a sheet;
An image forming apparatus comprising: a sheet post-processing unit that receives the sheet on which the image is formed by the image forming unit and performs post-processing;
The image forming apparatus according to claim 1, wherein the sheet post-processing unit is the sheet post-processing apparatus according to claim 1. Image forming means for forming an image on a sheet;
A sheet stacking member on which the sheet on which the image is formed by the image forming unit is stacked;
A discharge member that discharges the sheet in a direction along the sheet stacking member and stacks the sheet on the sheet stacking member;
A discharge control device for controlling the discharge speed of the sheet by driving the discharge member, and setting the discharge speed larger than before when the number of sheets discharged to the sheet stacking member exceeds a predetermined number; An image forming apparatus comprising:

Images