JP2011068465A - Sheet stacking device, postprocessing device and image forming system having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To register the sheet width direction to an accurate position by aligning the edge, when stacking a sheet in a predetermined position of a tray. <P>SOLUTION: This sheet stacking device includes the tray 29 for stacking a carried-out sheet, a regulating stopper for regulating the sheet edge, a paper ejecting rotary body 35 for transferring the sheet carried out on the tray toward a stopper, a support means for supporting this paper ejecting rotary body in an operation position for contacting with the sheet on the tray, and a registering means for registering the side edge in the paper ejecting orthogonal direction of the sheet to a reference position. The registering means is constituted of side guides 32a and 32b for regulating the side edge of the sheet carried out on the tray and a shift means for moving a position of these side guides in the paper ejecting orthogonal direction between a standby position and a registering position, and the support means is constituted of a rotary shaft 38 connected to a driving means and a frame member 37 for supporting this rotary shaft. The paper ejecting rotary body is movably journaled in the axial direction by the rotary shaft, and is positioned by an elastic member acting in this axial direction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a post-processing apparatus that performs post-processing such as paper binding on a sheet transported from an image forming apparatus such as a copying machine or a printer, and a sheet aligning mechanism that aligns the sheet transported on a tray to a predetermined position. Regarding improvement.

  In general, this type of sheet stacking apparatus is widely known as an apparatus for stacking sheets sent from a paper discharge path on a tray, and is used as a unit for stacking and stacking sheets sent from an image forming apparatus in a post-processing apparatus, for example. Has been. The post-processing device is known as a device that performs binding processing, punching processing, and the like on a bundle of sheets that have been aligned and stacked on a tray, and stores them in a stack tray.

  Conventionally, in such an apparatus, a processing tray is disposed downstream of the sheet discharge outlet, a stack tray is disposed downstream of the processing tray, and a sheet (bundle) post-processed by the processing tray is stored in the stack tray. Are known. For example, in Patent Document 1, a processing tray is disposed on the downstream side of the sheet discharge outlet and a processing tray is disposed on the downstream side. A structure is disclosed in which the leading end is supported by a stack tray and the trailing end of a sheet is supported by a processing tray.

  In such an apparatus, the sheet edge is positioned at a predetermined restriction stopper while the sheet conveyed from the sheet discharge outlet is bridge-supported between two trays, and at the same time, the width of the sheet is set to a predetermined reference position. There is a need to position the post-processing position in alignment. For this reason, in Patent Document 1, a roller that can be raised and lowered is provided above the processing tray, and after the leading end of the sheet reaches the stack tray from the sheet discharge port, the roller is lowered from the upper retracted position to an operating position that contacts the sheet. Yes. The roller is rotated in the direction opposite to the paper discharge direction, and the trailing edge of the sheet carried out from the paper discharge port is abutted and aligned with the restriction stopper. At the same time, the tray is provided with an alignment mechanism for aligning the side edge of the sheet with the reference position, and aligns the sheet whose position of the rear end is regulated in the direction perpendicular to the sheet discharge.

  Conventionally, when a sheet is carried out from a sheet discharge port to a tray having a step, a sheet discharge rotator such as a roller and a belt is provided on the tray so as to be movable up and down. At the timing of passing, the sheet moves from the retracted position to an operating position that engages with the sheet, and the sheet is abutted against the restriction stopper by the conveying force of the rotating body. Then, the position is regulated and the sheet is shifted in the orthogonal direction. The movement of the sheet in the width direction is controlled so that the sheet discharge rotator is retracted upward and the movement is not obstructed.

JP 2006-248686 A

  As described above, the sheet sent to the sheet discharge path is carried out from the sheet discharge outlet onto the tray, and is struck against the restriction stopper by the sheet discharge rotator disposed on the tray. There are the following problems in the sheet stacking structure in which the widths are aligned and aligned.

  The sheet carried on the tray is abutted and conveyed against the stopper by the sheet discharge rotating body, and the sheet is moved in the direction perpendicular to the sheet discharge by the aligning means. When the sheet is moved in the direction perpendicular to the sheet discharge, if the sheet discharge rotator presses the sheet and is strongly engaged, the sheet shifting movement is obstructed. For this reason, the side edge of the sheet is bent, wrinkles are generated, or misalignment is caused.

  Although this state is shown in FIG. 10, a sheet is carried into the tray 60 from the sheet discharge port, and this sheet is transferred toward a stopper (not shown) by a sheet discharge rotating body 61 disposed above the tray. The left and right alignment plates 62a and 62b move the sheet in the direction perpendicular to the sheet discharge and align it with the alignment reference. At this time, one or a plurality of rotating bodies arranged at the center of the sheet engage with the sheet, The engaging force is engaged by a pressure that is sufficient to transfer the sheet to the stopper by the paper discharge rotating body.

  For this reason, the sheet | seat with a weak waist or the sheet | seat curled beforehand may bend the side edge. At the same time, the sheet whose side edge is pressed in the width direction with the central portion being constrained by the sheet discharge rotator returns to its original position when the alignment plate is retracted to the standby position when the side edge curls. There will be a problem of inconsistency.

  Conventionally, in order to solve such a problem, an elevating mechanism for retracting the sheet discharge rotator to the upper side of the tray is provided, and the sheet is moved away from the sheet when the sheet is moved by the alignment plate. . However, this elevating mechanism detects the trailing edge of the sheet carried out from the sheet discharge port with a sensor, and retracts the rotating body after an expected time for the sheet to reach the stopper based on the signal.

  Therefore, if the timing of retracting the sheet discharge rotator from the sheet is incorrect, the above-described problems are caused, and an interval time for executing sheet conveyance, sheet discharge rotator retraction (disengagement), and sheet width shifting is required. Therefore, high-speed integration was impossible.

  Accordingly, the present inventor has come up with the idea that the above-mentioned problem can be solved by moving the sheet discharge rotator in the same direction following the movement in the width direction of the sheet when the sheet is shifted in the width direction.

An object of the present invention is to provide a sheet stacking apparatus capable of aligning and aligning the sheet width direction at an accurate position when stacking sheets at a predetermined position on a tray.
Another object of the present invention is to provide a sheet stacking apparatus capable of improving the processing efficiency by aligning and stacking continuously fed sheets at predetermined positions on the tray at high speed.

  In order to achieve the above object, according to the present invention, a sheet discharge rotator for transferring a sheet toward a regulating stopper and a aligning means for aligning the sheet width direction with a predetermined alignment reference are arranged on a tray means for stacking and supporting the sheets. Then, the support means for the paper discharge rotator is composed of a rotating shaft connected to the driving means and a frame member that supports the rotating shaft. At this time, the discharge rotator is supported by a rotary shaft so as to be movable in the axial direction, and is positioned by an elastic member acting in the axial direction. With this configuration, when the sheet is moved by the aligning means, the sheet discharge rotator moves following the sheet, causing problems such as bending of the sheet side edge, wrinkles, or sheet misalignment. There is nothing.

  To further explain the configuration, a tray means (29) for stacking sequentially delivered sheets, a sheet end regulating means (30) for regulating the edge of the sheet delivered to the tray means, and the tray means A sheet discharge rotator (35) for transferring the sheet carried to the sheet end regulating means, a support means for supporting the sheet discharge rotator at an operating position in contact with the sheet on the tray means, and the tray means. Alignment means (32) for aligning the side edges of the stacked sheets in the sheet discharge orthogonal direction to the reference position.

  The aligning means moves side guide plates (32a, 32b) that regulate the side edges of the sheets carried to the tray means, and moves the side guide plates between the standby position and the align position in the direction perpendicular to the sheet discharge. The supporting means is constituted by a rotating shaft (38) coupled to the driving means and a frame member (37) for supporting the rotating shaft (38). The paper discharge rotator is supported by the rotary shaft so as to be movable in the axial direction, and is positioned by an elastic member acting in the axial direction.

  The elastic member has, for example, a pair of coil springs (45a, 45b) disposed opposite to each other on the left and right of the rotation shaft, and the discharge rotator is set to a predetermined discharge reference by the urging force of the springs. At the same time, the urging force is set to a force that does not cause the sheet to buckle due to the shifting action of the aligning means.

  The present invention is provided with a sheet discharge rotator for transferring a sheet carried on the tray means toward a predetermined regulating stopper, and an alignment means for shifting the sheet in the direction orthogonal to the sheet discharge. Since it is configured to follow the moving sheet and move in the same direction, the following effects can be obtained.

  Since the sheet carried on the tray is abutted and aligned with the regulation stopper by the sheet discharge rotator, the sheet is reliably positioned at a predetermined position. At the same time, the sheet side edges are aligned to the predetermined alignment reference by the alignment means. In particular, since the sheet discharge rotator moves in the sheet width direction following the sheet during the width alignment, the sheet side edge is not bent, wrinkled, or uneven alignment is not caused.

  As described above, the present invention supports the sheet discharge rotator so as to be movable in the sheet width direction, and positions the position with an elastic member such as a spring. Therefore, the present invention can be provided at a low cost with a simple structure. At the same time, it is not always necessary to provide an elevating mechanism for retracting the paper discharge rotating body from the sheet on the tray. In this case, the paper discharge mechanism can be configured simply and compactly.

  Furthermore, according to the present invention, it is possible to move the sheet in the direction perpendicular to the sheet discharge at the same time as the sheet carried on the tray is transferred to the regulating stopper by the sheet discharge rotating body. Accordingly, the sheets that are continuously carried out can be collected and aligned on the tray at high speed in a short time.

1 is an explanatory diagram of an overall configuration of an image forming system according to the present invention. FIG. 2 is an explanatory diagram of an overall configuration of a paper discharge unit (sheet stacking apparatus) in the image forming system of FIG. 1. FIG. 3 is an explanatory diagram of a lifting mechanism for a paper discharge rotating body in the paper unit of FIG. 2. 3A and 3B are explanatory views of a planar structure of the paper discharge unit of FIG. 2, wherein FIG. 3A is a plan view of the paper discharge unit, FIG. 2B is a central longitudinal sectional view of a paper discharge rotator, and FIG. Figure. FIG. 3 is an explanatory diagram illustrating a configuration of an alignment unit that aligns and aligns sheet side edges in the paper discharge unit of FIG. 2. FIGS. 3A and 3B are explanatory diagrams of an operation state of the paper discharge unit of FIG. 2, in which FIG. 3A is an operation state of sheet width alignment by the alignment unit, and FIG. Explanatory drawing of the whole structure of the post-processing apparatus in the system of FIG. FIG. 7 is a detailed explanatory diagram of a main part of the post-processing apparatus of FIG. FIG. 2 is a block diagram showing a control configuration in the image forming system of FIG. 1. Explanatory drawing of the sheet alignment state in the conventional sheet stacking apparatus.

The present invention will be described in detail below based on the preferred embodiments shown in the drawings. FIG. 1 shows an image forming system according to the present invention. After an image forming apparatus A for forming an image on a sheet and sheets conveyed from the image forming apparatus A are collected and subjected to post-processing such as binding processing. It comprises a processing apparatus B and a sheet stacking apparatus C built in the post-processing apparatus B. Then, the sheets formed by the image forming apparatus A are stacked and stacked by the sheet stacking apparatus C, and the sheet bundle is subjected to binding processing and stored in the stack tray 21.
Hereinafter, “sheet stacking apparatus C”, “image forming apparatus A”, and “post-processing apparatus B” will be described in this order.

[Sheet Accumulator]
The sheet stacking apparatus C according to the present invention is provided with a sheet discharge path P1 for sequentially carrying out the sheets as shown in FIG. In the paper discharge path P1, a carry-in port 23, a paper discharge port 24, and a transport roller 26 are arranged. The apparatus shown in FIG. 2 is disposed in the apparatus housing 20 so that a sheet discharge path P1 having a carry-in port 23 and a discharge port 24 crosses the apparatus, and the carry-in port 23 is a main body discharge port of the image forming apparatus A described later. 15 is carried into the apparatus. Further, a step is formed in the paper discharge port 24, and a tray unit (hereinafter referred to as “processing tray”) 29 is disposed on the downstream side, and a stack tray 21 is disposed on the downstream side of the tray unit 29.

  The processing tray 29 aligns and stacks the sheets from the paper discharge outlet 24 and performs a binding process (post-processing). For this reason, the processing tray 29 includes sheet end regulating means (hereinafter referred to as “regulation stopper”) 30 for regulating the position of the edge in the sheet ejection direction, and sheet ejection rotators 31 and 35 for transferring the sheet to the regulation stopper 30. Has been placed. The illustrated sheet discharge rotators 31 and 35 include a forward / reverse roller 35 and a scraping belt 31.

  The sheet discharge rotators 31 and 35 are arranged so as to engage with the sheet carried on the processing tray and transfer it to the restriction stopper 30. At the same time, the forward / reverse roller 35 is supported by the apparatus frame so as to be movable up and down between an operating position Fp in contact with the uppermost sheet on the processing tray and a retracted position Tp separated from the sheet. This is because the leading edge of the sheet carried out from the paper discharge port 24 is surely entered between the forward / reverse roller 35 and the uppermost sheet. Further, the above-described scraping belt 31 is not limited to a belt, and may be composed of a paddle member, a roller, or the like.

[Forward / reverse roller configuration]
The present invention is characterized in that the forward / reverse roller 35 is configured as follows. The sheet discharge rotator (forward / reverse roller) 35 is composed of a rotator that conveys a sheet by a frictional force, such as a roller and a belt, and is disposed on the apparatus frame so as to be engaged with the sheet on the processing tray 29 by a supporting means. Yes.

  The configuration will be described in detail with reference to FIGS. FIG. 3 shows a configuration of a paper discharge rotator (forward / reverse roller; the same applies to the following) 35. The paper discharge rotator 35 shown in FIG. Then, the base end portion 37 a of the arm-shaped frame member 37 is supported by the rotation support shaft 36. A front end portion 37 b of a frame member (hereinafter referred to as “bracket”) 37 is arranged so as to hang down on the processing tray 29. The bracket 37 may be constituted by one arm member, but the illustrated one is constituted by a pair of arm members arranged in parallel with a distance therebetween. The rotary shaft 38 is axially supported at the tip of the arm member.

  The rotation support shaft 36 is connected to a forward / reverse rotation motor M1 that rotationally drives the sheet discharge rotator 35, and a drive pulley 5 is provided integrally therewith. The rotation of the rotation support shaft 36 is configured to transmit the rotation of the forward / reverse rotation motor M1 to the rotation shaft 38 through the drive pulley 39a, the transmission belt 40, and the driven pulley 39b.

  Also, the rotary spindle 38 is connected to a lifting motor MS that swings and rotates the bracket 37. As shown in FIG. 4, a collar 41 is loosely fitted on a rotation support shaft 36 as shown in FIG. 4, and the collar 41 is fixed to a bracket 37. On the other hand, a gear G1 is fixed to the collar 41, and the drive shaft Mx of the lifting motor MS is gear-coupled to the gear G1. Accordingly, the bracket 37 moves up and down between the operating position Fp in the solid line state of FIG. 3 and the retracted position Tp of the chain line in FIG.

  A spring clutch (not shown) is built in between the gear G1 of the collar 41 and the drive shaft Mx of the elevating motor MS. When the bracket 37 is at the retracted position Tp located above the processing tray, it hits the stopper 42 and moves to it. The above rotation is prevented, and at the same time, the spring clutch is locked at that position. Then, the reverse rotation of the collar 41 (clockwise rotation in FIG. 3) loosens the spring clutch, and the bracket 37 rotates clockwise about the rotation support shaft 36. The bracket 37 is placed on the sheet on the processing tray in the solid line state of FIG. It is comprised so that it may fall to the state which contact | abuts.

  Accordingly, the sheet discharge rotator 35 is made of a material and a shape that come into contact with a sheet such as a roller and a belt and apply a conveying force to the sheet by the frictional force thereof. As an example, FIG. 4 shows a case where the paper discharge rotating body 35 is constituted by a roller body. The roller body is made of a rubber material, a resin material, and the like, and the outer periphery is set to a friction coefficient suitable for applying a conveying force to the sheet. A shaft sleeve 43 made of metal, resin, or the like is integrally formed on the shaft center, and a shaft hole 38x adapted to the rotation shaft 38 is provided on the shaft center.

  The paper discharge rotator 35 formed in this way is fitted to the rotary shaft 38 supported by the bracket 37 as described above so that the roller body (paper discharge rotator) 35 can move in the axial direction as follows. The shaft hole 38x of the roller body 35 is loosely fitted to the rotary shaft 38 so as to be movable in the axial direction. The rotary shaft 38 and the shaft sleeve 43 are each provided with a key groove. The rotation is connected to the roller body 35 so as to be transmitted.

  That is, as shown in FIGS. 4B and 4C, the shaft hole 38x is formed to have an inner diameter slightly larger than the outer diameter of the rotating shaft 38, and the rotating shaft 38 and the roller body 35 are coupled by the key 44. . Accordingly, the roller body (friction rotating body) 35 is transmitted with the rotation of the rotation shaft 38 by the key 44, and at the same time can move by Δx in the axial direction (left and right direction in FIG. 4A).

  The sheet discharge rotator 35 configured as described above is attached to the rotation shaft 38 of the distal end portion 37b of the bracket 37 supported by the rotation support shaft 36 so that the base end portion 35a is movable in the axial direction. Therefore, the sheet discharge rotator 35 that is movable in the axial direction along the rotation shaft 38 is positioned by the elastic member 45 in the axial direction. The elastic member 45 regulates its position by applying an urging force in the axial direction to the sheet discharge rotator 35 movable in the axial direction. For this reason, the illustrated apparatus includes a pair of 45 a and 45 b disposed on both sides of the sheet discharge rotating body 35 in the sheet width direction.

  The illustrated coil springs 45 a and 45 b are arranged so that one end is locked to the side wall of the bracket 37 and the other end is pressed against the side portion of the sheet discharge rotating body 35 in the axial direction. The paper discharge rotator 35 is positioned at a position where the biasing forces of the springs 45a and 45b are balanced. That is, the sheet discharge rotator 35 is supported by a rotary shaft 38 supported by a bracket 37 so as to be movable in the axial direction, and its axial position is set to a predetermined position (for example, a sheet center) by an elastic member (coil spring) 45. It is positioned.

  The urging force (Sp shown in FIG. 4C) acting on the sheet discharge rotator 35 of the elastic member 45 is set to a force smaller than the sheet shifting force (Fp shown in FIG. 4C). . In other words, the elastic member 45 stops the paper discharge rotator 35 at a preset axial position when there is no load, and moves in the axial direction along the rotary shaft 38 by a displacement amount (Δx) when receiving an axial force from the sheet. To do.

  Further, the processing tray 29 is arranged such that the sheets stacked and aligned on the tray are abutted against the restriction stopper 30 to position the leading edge or the trailing edge, and at the same time, the sheet conveyance orthogonal direction is set to a predetermined reference position. Alignment means 32 is provided to match the above. The details of the aligning means 32 will be described in the “post-processing device” described later. The tray means 29 is provided with side guides 32a and 32b for aligning the loaded sheets in the direction perpendicular to the sheet discharge. . The aligning means 32 is configured to align the sheets having different width sizes in the center reference or the side reference. As will be described later, the aligning unit 32 sets the alignment reference position based on the center reference or the side reference, and aligns the sheets to the alignment reference position.

  Further, as shown in FIG. 5, the alignment means 32 has a left and right independent alignment motors Ma and Mb arranged on the apparatus frame, and a pair of left and right sides on a drive belt 28v spanned between a pair of pulleys 28a and 28b. Guides 32a and 32b are connected. Accordingly, the pair of left and right side guides 32a and 32b move left and right along the guide groove 29x, and the alignment motors Ma and Mb rotate by the same amount in opposite directions.

  The pair of left and right side guides 32a and 32b is provided with a limit sensor (not shown) for detecting the home position. Therefore, the control means (not shown) controls the alignment motors Ma and Mb so that the pair of left and right side guides 32a and 32b reciprocate in the order from the home position to the standby position Wp and the alignment position Ap.

[Configuration of Image Forming Apparatus]
The image forming apparatus A includes a paper feeding unit 2, an image forming unit 3, and an image data storage unit in a casing 1. The sheet feeding unit 2 is composed of, for example, a plurality of sheet feeding cassettes 2a, 2b, 2c, and 2d, and pre-selected standard size sheets are stored in the cassettes 2a to 2d. The paper feed unit 2 is provided with a manual feed tray 1x so that the user can insert sheets according to the purpose of use. A sheet set in the sheet feeding unit 2 having such a configuration has a sheet condition such as its size, paper quality (coating paper or plain paper), paper thickness (thick paper or thin paper), and the control panel 16 described later. It is configured to input information from.

  The image forming unit 3 is configured to form an image on a sheet sent from the paper feeding unit 2, and the illustrated one shows an electrostatic image forming mechanism. The image forming unit 3 is provided with a photosensitive drum 10, a print head (a light emitting device such as a laser beam or LED light) 9 for forming a latent image on the drum surface, and a developing device 11. The image ink (toner) formed on the photosensitive drum 10 is image-transferred by the transfer charger 12.

  The sheet on which the image has been transferred in this manner is carried out to the paper discharge path 14 via the fixing roller 13. In addition, the image forming unit 3 is not limited to the illustrated electrostatic image forming mechanism, and various image forming mechanisms such as an ink jet image forming mechanism and an offset image forming mechanism can be employed.

  Although not shown, the image data storage unit is configured by a storage memory for image data formed on the photosensitive drum 10 by the print head 9 of the image forming unit 3 so that data can be transferred from the image reading unit 5 to the storage unit. It has become. Data is also transferred to the image data storage unit from, for example, a networked computer.

  In the image forming apparatus A configured as described above, an image reading unit 5 for reading a document image is mounted on the upper portion thereof, and a document feeding unit 8 is further mounted on the upper portion thereof. The image reading unit 5 includes a platen 5a for setting an original sheet, a reading carriage 6 for scanning an original image along the platen 5a, and a photoelectric conversion means 7 for forming an image of reflected light from the original image and performing photoelectric conversion. Is provided inside. The document feeding unit 8 includes a feeder mechanism that separates document sheets set on the sheet feeding tray 8a one by one and automatically feeds them to the platen 5a of the image reading unit 5.

[Configuration of post-processing equipment]
The post-processing apparatus B connected to the image forming apparatus A will be described. As shown in FIG. 7 and the detailed configuration in FIG. 8, the post-processing apparatus B has a discharge port 24 having a carry-in port 23 and a discharge port 24 connected to the main body discharge port 15 of the image forming apparatus A. P1 is provided. The processing tray 29 described above is disposed downstream of the paper discharge port 24. A pair of paper discharge rollers 26 (26a, 26b) is disposed in the paper discharge path P1, and the forward / reverse rotation roller 35 and the aligning means 32 described above are disposed in the processing tray 29.

  The post-processing apparatus B receives a sheet on which an image has been formed from the main body discharge port 15 of the image forming apparatus A, and (1) accommodates the sheet in the stack tray 21 without performing post-processing (described later in “Print”). Out mode "), or (2) after aligning the sheets from the main body discharge port 15 into a bundle and stapling them, and then storing them in the stack tray 21 (" stapling mode "described later)) or ( 3) After the sheets from the main body discharge port 15 are arranged in a bundle, the sheets are folded into a booklet and stored in the booklet storage tray 22 (a “sheet bundle folding mode” described later).

  For this reason, the post-processing apparatus B is provided with a paper discharge path P1 in the apparatus housing 20 as shown in FIG. A first switchback conveyance path SP1 and a second switchback conveyance path SP2 are arranged in the paper discharge path P1 and branch from now on to transfer the sheet in the reverse direction. The first switchback transport path SP1 is disposed on the downstream side of the paper discharge path P1, and the second switchback transport path SP2 is disposed on the upstream side of the carry-in first switchback transport path SP1.

  The processing tray 29 described above is disposed on the downstream side of the first switchback transport path SP1, and the stack tray 21 is connected to the downstream side thereof. An accumulation guide 47 is disposed on the downstream side of the second switchback conveyance path SP2, and a booklet storage tray 22 is disposed on the downstream side thereof. Further, in the paper discharge path P1, a carry-in roller 25 that conveys the sheet from the carry-in port 23 toward the paper discharge port 24, and post-processing that performs post-processing such as stamping (stamping means) and punching (punching means) on the sheet. A unit 19 is provided.

[Configuration of the first switchback transport path SP1]
As described above, the first switchback transport path SP1 disposed on the downstream side (rear end portion of the apparatus) of the paper discharge path P1 is configured as follows. In the paper discharge path P1, a pair of paper discharge rollers 26 and a paper discharge outlet 24 are provided at the exit end, and the above-described processing tray 29 is provided on the downstream side while forming a step with the paper discharge outlet 24. The processing tray 29 is a tray that stacks and supports sheets from the sheet discharge outlet 24.

  Above the processing tray 29, the above-described forward / reverse roller (paper discharge rotator) 35 is disposed so as to be movable up and down between an operating position Fp in contact with the sheet on the tray and a retracted position Tp (a chain line position in FIG. 3). Has been. A forward / reverse motor M1 is connected to the forward / reverse roller 35 and rotates clockwise when a sheet enters the processing tray 29, and rotates counterclockwise after the trailing edge of the sheet enters the processing tray. To be controlled.

  31 is a paper discharge rotating body, and one end thereof is pressed against the paper discharge roller pair 26 and rotates counterclockwise in FIG. 2 so as to transfer the sheet on the processing tray to the regulating stopper 30 side. The illustrated sheet discharge rotator 31 is formed of an endless belt, and is pivotally supported so that the front pulley side hangs down on the processing tray 29 around the pulley shaft 26z of the sheet discharge roller 26b.

  In the sheet discharge path P1 configured as described above, the sheet from the sheet discharge outlet 24 enters the processing tray 29 and is conveyed toward the stack tray 21 by the forward / reverse rotation roller 35, and the rear end of the sheet from the sheet discharge outlet 24. After entering the processing tray 29, when the forward / reverse rotation roller 35 is reversely rotated (counterclockwise in the figure), the sheet on the processing tray is transferred in the direction opposite to the paper discharge direction. At this time, the sheet discharge rotator 31 conveys the rear end of the sheet along the processing tray 29 toward the restriction stopper 30 in cooperation with the forward / reverse roller 35.

  A restriction stopper 30 and a stapler device 33 for restricting the position of the rear end of the sheet are disposed at the rear end of the processing tray 29 in the paper discharge direction. The illustrated stapler device 33 staples one or more rear end edges of the sheet bundle stacked on the processing tray. Further, the processing tray 29 is provided with a carry-out mechanism for carrying out the bound sheet bundle to the stack tray 21.

  The illustrated carry-out mechanism includes a grip claw 34a that grips a sheet bundle, a drive arm 34b that reciprocates the grip claw 34a left and right along the processing tray 29, and a paper discharge motor ME that operates the drive arm 34b. ing. The processing tray 29 is provided with alignment members 32a and 32b for aligning the width direction of the sheets accumulated on the tray, and the configuration of the alignment members 37a and 37b is as described above.

  The first switchback conveyance path SP1 configured as described above aligns the sheets from the sheet discharge outlet 24 on the processing tray 29 in the “steple binding mode”, and this sheet bundle is end-face binding stapler device 33. Then, one or a plurality of the rear end edges are stapled. In the “print-out mode”, the sheet from the sheet discharge outlet 24 is conveyed toward the stack tray 21 along the processing tray 29 without being switched back. As shown in the figure, the sheet to be stapled is bridge-supported by the processing tray 29 and the stack tray 21 disposed downstream thereof. As a result, the apparatus can be made compact.

[Configuration of second switchback transport path]
The second switchback transport path SP2 branched from the paper discharge path P1 is provided with a stacking guide 47 as shown in FIG. 7, and the sheets from the paper discharge path P1 are aligned and stacked on this guide to form a pair of folding sheets. Fold with rollers 48. A saddle stitching stapler device 49 is disposed in the stacking guide 47 and binds the center of the sheet bundle before folding. The sheet bundle folded by the folding roller 48 is stored in the booklet storage tray 22.

[Description of control configuration]
The control configuration of the above-described image forming system will be described with reference to the block diagram of FIG. The image forming system shown in FIG. 1 includes a control unit (hereinafter referred to as “main body control unit”) 50 of the image forming apparatus A and a control unit (hereinafter referred to as “post-processing control unit”) 55 of the post-processing apparatus B. The main body control unit 50 includes a print control unit 51, a paper feed control unit 52, and an input unit (control panel) 16.

  Then, an “image forming mode” and a “post-processing mode” are set from the input unit (control panel) 16. The image forming mode sets mode settings such as color / monochrome printing, duplex / single-sided printing, and image forming conditions such as sheet size, sheet paper quality, number of printouts, and enlarged / reduced printing. The “post-processing mode” is set to, for example, “print-out mode”, “steple finishing mode”, “binding binding finishing mode”, or the like.

  In addition, the main body control unit 50 sends a post-processing finishing mode and the number of sheets, information on the number of copies and binding mode (one-position binding or two or more bindings) information, and the sheet thickness of the sheet on which an image is formed. Data transfer such as information. At the same time, the main body control unit 50 transfers a job end signal to the post-processing control unit 55 every time image formation is completed.

  The post-processing mode will be described. In the “print-out mode”, the sheet from the paper discharge port 24 is stored in the stack tray 21 without performing post-processing. In this case, the sheets are carried out from the discharge outlet 24 to the stack tray 21 without being aligned and stacked on the processing tray 29. In the “steple finishing mode”, the sheets from the sheet discharge outlet 24 are stacked on the processing tray 29 and aligned, and the sheet bundle is bound by the stapler device 33 and then stored in the stack tray 21. In this case, the sheet to be imaged is in principle designated by the operator to a sheet of the same paper thickness and the same size.

  In the “bookbinding binding finishing mode”, sheets formed by the image forming apparatus A are aligned and accumulated on the processing tray 29, and finally, the cover sheet is image-formed by the image forming apparatus A and superimposed on the sheets on the processing tray. After aligning and stapling, the stack tray 21 is accommodated. In this case, the cover sheet is designated by the operator as a cardboard sheet prepared in the sheet feeding unit 2.

[Post-processing control unit]
The post-processing control unit 55 is configured by a control CPU (control means; the same applies hereinafter) that operates the post-processing apparatus B in accordance with a designated post-processing mode. The post-processing control unit 55 includes a ROM 56 that stores an operation program and a RAM 57 that stores control data.

[Control of paper output rotating body]
The rotation of the sheet discharge rotator (forward / reverse roller) 35 is stopped at the timing when the sheet is moved downward from the retracted position Tp to the operating position Fp and when the position of the rotator reaches the restriction stopper 30 and the position is restricted.

  In this way, the sheet discharge rotator (forward / reverse roller) 35 moves down from the retracted position Tp to the operating position Fp and transfers the sheet on the processing tray 29 to the regulating stopper 30. At this time, as shown in FIG. 4, the sheet discharge rotating body 35 is positioned at a specified position of the frame member (bracket) 37 by the spring balance of the left and right elastic members (coil springs) 45a and 45b. Positioning of the sheet discharge rotator 35 by the spring balance is in a no-load state at the retracted position Tp, and at this time, the roller body 35 is positioned at a predetermined position of the bracket 37 (for example, a position coincident with the sheet center).

  The configuration of the post-processing control unit 55 will be described together with its operation program. Whether the bracket 37 is positioned at the retracted position Tp is determined based on a signal from a position sensor (not shown) at the time of initialization (initialization) when the apparatus is activated. When the sensor signal is OFF, the lift motor MS is activated in the upward direction to position the bracket 37 at the retracted position Tp. At the same time, this operation program is configured to detect when the leading edge of the sheet reaches the carry-in entrance 23 by the entrance sensor S1 and to rotationally drive the paper discharge roller pair 26.

  At the same time, the paper discharge sensor S2 detects the trailing edge of the sheet and starts a timer. By this timer time-up signal, the lift motor MS is started in the upward and downward direction to swing the bracket 37 and rotate the paper discharge. The body (forward / reverse roller) 35 is lowered from the retracted position Tp to the operating position Fp. The forward / reverse rotation motor M1 rotates in the clockwise direction in FIG. 2 before the sheet discharge rotator (forward / reverse rotation roller) 35 reaches the operating position Fp.

  As a result, the sheet conveyed from the sheet discharge port 24 toward the processing tray 29 is guided at the leading end between the forward / reverse roller 35 and the uppermost sheet stacked on the processing tray. Then, the sheet is conveyed to the left side in FIG. 2 by the rotation of the forward / reverse roller 35 in the paper discharge direction (clockwise in FIG. 2). Therefore, the control means (control CPU) 55 detects the trailing edge of the sheet by the paper discharge sensor S1, and stops the forward / reverse rotation roller 35 at the expected time when the trailing edge is carried onto the paper discharge tray.

  The control means (control CPU) 55 reverses the forward / reverse motor M1 in the direction opposite to the paper discharge. Then, the sheet sent onto the processing tray is transferred to the restriction stopper 30 along the uppermost sheet on the tray, and the forward / reverse rotation roller 35 is stopped after a time for the sheet leading edge to reach the restriction stopper 30. Next, the control means (control CPU) 55 positions the alignment means 32 described above from the standby position to the alignment position.

  The sheet aligning operation by the aligning means 32 will be described with reference to FIG. FIG. 5A shows the state of the side guides 32a and 32b constituting the alignment means 32 in the standby position Wp, and FIG. 5B shows the state of the alignment position Ap. When the side guides 32a and 32b move from the standby position Wp to the alignment position Ap, the sheet that is skewed and is carried into the processing tray is pressed by the guide surface and is moved toward the alignment reference position (sheet center). .

  At this time, the sheet discharge rotator 35 is subjected to an action of a displacement force (sheet width-shifting force) Fp in the axial direction from the sheet that is moved closer. Although the displacement force Fp of the sheet varies depending on the sheet material, the (displacement force Fp)> (biasing force) with respect to the urging force Sp of the elastic members (coil springs) 45a and 45b applied to the sheet discharge rotating body 35. Sp). That is, the sheet displacement force (experimental value) predicted in advance is set to be larger than the urging force Sp acting on the sheet discharge rotating body 35 of the elastic member 45.

  Under such conditions, when the sheet is moved by the side guides 32a and 32b, the sheet discharge rotator 35 receives the displacement force Fp of the sheet along the rotation shaft 38 as shown in FIG. 6B. Then, it moves by the displacement amount (Δx) following the sheet. As a result, the sheet side edge is curved and does not cause irregularities, bending, wrinkles and the like. Then, when the subsequent sheet is carried into the processing tray 29, the sheet discharge rotating body 35 is moved upward by the above-described lifting motor MS, and at this time, it becomes a no-load state and returns to the specified position by spring balance.

  In the present invention, the case where the pair of the elastic members 45 are arranged so as to face the left and right of the sheet discharge rotating body 35 when the alignment means 32 is set as the center reference has been described. When setting, the elastic member 45 may be disposed on the movable side guide side. Further, the elastic member 45 is not limited to the illustrated coil spring, but a bush made of, for example, a ring-shaped sponge may be disposed between the wall surface of the bracket 37 and the sheet discharge rotating body 35.

  Further, in the present invention, the structure has been described in which the sheet discharge rotator 35 moves up and down between the operation position Fp that engages with the sheet on the processing tray and the retreat position Tp that is retreated upward from this. The body 35 may be fixedly disposed at a position where the body 35 is always engaged with the uppermost sheet on the processing tray.

A Image forming apparatus B Post-processing apparatus C Sheet stacking apparatus 21 Stack tray 23 Loading port
24 Paper discharge port 29 Processing tray (tray means)
30 Sheet edge regulating means (regulating stopper)
31 Paper discharge rotating body (scraping belt)
32 Alignment means 32a Side guide 32b Side guide 35 Paper discharge rotating body (forward / reverse roller)
36 Rotating spindle (drive shaft)
37 Frame member (bracket)
37a Base end part 37b Tip part 38 Rotating shaft 38x Shaft hole 39a Drive pulley 39b Driven pulley 40 Drive belt 41 Collar 42 Stopper 43 Shaft sleeve 44 Key 45 Elastic member 45a Coil spring 45b Coil spring 50 Main body control part 55 Post-processing control part (Control CPU)
M1 Forward / reverse motor MS Lifting motor Sp Energizing force Fp Width-adjusting force

Claims (9)

Tray means for stacking sheets to be sequentially carried out;
Sheet end regulating means for regulating the edge of the sheet carried to the tray means;
A paper discharge rotator for transferring the sheet carried on the tray means toward the sheet end regulating means;
Supporting means for supporting the discharge rotating body at an operating position in contact with the sheet on the tray means;
Aligning means for aligning the side edges of the sheets stacked on the tray means in the discharge orthogonal direction to a reference position;
With
The alignment means includes
A side guide plate for regulating a side edge of the sheet carried to the tray means;
Shift means for moving the side guide plate in the direction perpendicular to the paper discharge between the standby value and the alignment position;
Consists of
The support means is
A rotating shaft coupled to the driving means;
A frame member that supports the rotating shaft;
Consists of
The sheet stacking device is characterized in that the sheet discharge rotating body is supported by the rotating shaft so as to be movable in the axial direction, and is positioned by an elastic member acting in the axial direction. The rotating shaft is connected to a drive means capable of forward and reverse rotation,
2. The sheet stacking apparatus according to claim 1, wherein the sheet discharge rotating body switches back the sheet carried on the tray unit and transfers the sheet to the sheet end regulating unit. The support means is attached to the apparatus frame so as to be swingable so as to move up and down between an operating position where the sheet discharge rotator contacts the sheet on the tray means and a standby position retracted from the sheet. The sheet stacking apparatus according to claim 1. The elastic member is composed of a pair of coil springs,
This pair of coil springs
2. The sheet stacking apparatus according to claim 1, wherein the sheet stacking device is disposed so as to face the sheet discharge rotator, and an urging force in the opposite direction is applied to the sheet discharge rotator. The elastic member is composed of a pair of left and right coil springs fitted on the rotating shaft with the sheet discharge rotating body interposed therebetween,
The sheet stacking apparatus according to claim 1, wherein the pair of coil springs applies an urging force in an opposite direction to the sheet discharge rotating body to position an axial position. A sheet discharge path for sequentially carrying out the sheets is disposed on the upstream side of the tray unit, and a stack tray for storing sheets from the tray unit is disposed on the downstream side,
2. The sheet stacking apparatus according to claim 1, wherein post-processing means for performing post-processing on the stacked sheets is arranged in the tray means. The said elastic member is connected with the said side guide plate so that the urging | biasing force which acts on the said discharge rotary body in response to the alignment direction movement of the said side guide plate may change. The sheet stacking apparatus described. A paper discharge path for sequentially unloading sheets from the paper discharge port;
Tray means disposed on the downstream side of the paper discharge port;
Post-processing means disposed on the tray means;
A stack tray disposed downstream of the tray means;
Consisting of
A post-processing apparatus, wherein the tray means has the configuration according to any one of claims 1 to 7. An image forming apparatus for forming an image on a sheet;
A post-processing device that performs post-processing by collecting and stacking sheets of images formed by the image forming apparatus; and
Consisting of
An image forming system comprising the post-processing apparatus having the configuration according to claim 8.

Images