Sheet loading apparatus, sheet processing device, and image forming system

Abstract

To provide a structure which enables a sheet or a sheet bundle on a first tray 49 to be taken out easily after a job ends.SOLUTION: Alignment plates 401, 402 may move up or down to a first position where alignment of an uppermost sheet may be performed and a second position located higher than the first position. One of the alignment plates 401, 402 moves to the other side in a width direction relative to one end in the width direction of a sheet loaded on a first tray 49 after a job for loading the sheet onto the first tray 49 ends and the alignment plate moves up from the first position to the second position.SELECTED DRAWING: Figure 29

Description

Technical Field

[0001] The present invention relates to a sheet loading device for loading sheets, a sheet processing device including the sheet loading device, and an image forming system including the sheet processing device.

Background Art

[0002] Patent Document 1 discloses a configuration of a sheet loading device including a liftable loading tray and a pair of alignment members that perform alignment in the width direction of the sheet discharged onto the loading tray on the loading tray. In the case of the configuration described in Patent Document 1, when the job is completed, the pair of alignment members are positioned at a position away from the sheet in the width direction with respect to the sheet alignment position and at a home position above the alignment position.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As described in Patent Document 1, when the pair of alignment members are positioned at the home position after the job is completed, since the pair of alignment members are located outside the sheet in the width direction of the sheet, there is a risk that the pair of alignment members will interfere when the operator takes out the sheet or the sheet bundle on the loading tray.

[0005] An object of the present invention is to provide a configuration that facilitates taking out a sheet or a sheet bundle on a loading tray after the completion of a job.

Means for Solving the Problems

[0006] One aspect of the present invention includes a discharge unit that discharges a sheet in a discharge direction, a stacking tray that stacks the sheets discharged by the discharge unit, a lifting unit that raises and lowers the stacking tray, and a pair of alignment members that are located on both sides in the width direction of the sheet intersecting the discharge direction with respect to the uppermost sheet stacked on the stacking tray and align the uppermost sheet in the width direction. The pair of alignment members is moved by an alignment member moving unit between an alignment position for aligning the uppermost sheet in the width direction and a position separated from the uppermost sheet in the width direction from the alignment position. The pair of alignment members is vertically movable by an alignment member lifting unit between a first position where the uppermost sheet can be aligned and a second position above the first position and not interfering with the sheet discharged from the discharge unit. One of the pair of alignment members is a sheet stacking device that moves to the other side in the width direction from one end in the width direction of the sheet stacked on the stacking tray after the job of stacking the sheet on the stacking tray is completed and the alignment member has risen from the first position to the second position.

Advantages of the Invention

[0007] According to the present invention, productivity can be improved.

Brief Description of the Drawings

[0008]

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[0009] The embodiments will be described with reference to FIGS. 1 to 31. First, the schematic configuration of the image forming system of the present embodiment will be described with reference to FIG. 1.

[0010] [Image Forming System] In this embodiment, a copier is used as the image forming apparatus, and a sheet processing apparatus is connected to the opening of the sheet of this copier. The image forming system 1000 includes an image forming apparatus A and a sheet processing apparatus B. The sheet S on which an image is formed by the image forming apparatus A is received by the downstream sheet processing apparatus B, and is subjected to predetermined processing such as binding processing as necessary, and then sent to the downstream sending unit. The image forming apparatus A includes various structures such as, for example, a copier, a printer, a printing machine, a facsimile machine, and a multifunction machine having a plurality of these functions. Hereinafter, the image forming apparatus A and the sheet processing apparatus B will be described in detail. In the following description, with respect to the image forming apparatus A and the sheet processing apparatus B, the side where an operator such as a user operates the apparatus (for example, the side where an operation panel or operation buttons are provided) is referred to as the front side (the front side of the paper surface in FIGS. 1, 2, etc.), and the side opposite to the front side is referred to as the rear side (the back side of the paper surface in FIGS. 1, 2, etc.).

[0011] [Image Forming Apparatus] As shown in FIG. 1, the image forming apparatus A includes an image forming unit A1, an image reading unit A2, and an original document feeding unit A3. The image forming unit A1 includes a feeding unit 2, an image forming unit 3, a discharging unit 4, and a data processing unit 5 in the apparatus housing 1.

[0012] The feeding unit 2 includes a plurality of cassettes 2a, 2b, 2c, and each cassette 2a, 2b, 2c can store sheets S of different standard sizes selected in advance. The sheet S is, for example, paper, a plastic sheet, or the like. Each cassette 2a, 2b, 2c incorporates a separating mechanism for separating the internal sheets S one by one and a feeding mechanism for feeding out the sheets S. The sheet S stored in the feeding unit 2 configured in this way feeds out the sheet S of the size designated by the control unit 310 (FIG. 3) of the image forming apparatus A to the feeding path 6. The feeding path 6 is provided with a conveying roller 7 for conveying the sheets S supplied from the plurality of cassettes 2a, 2b, 2c to the downstream side, and a registration roller pair 8 disposed at the end of the path for aligning the leading edges of the sheets S. The sheet S whose leading edge is aligned by the registration roller pair 8 is fed to the downstream image forming unit 3 at a predetermined timing.

[0013] The supply path 6 is connected to a large-capacity cassette 2d and a manual feed tray 2e. The large-capacity cassette 2d is composed of an optional unit for storing sheets of a size that is consumed in large quantities. The manual feed tray 2e is configured to be able to supply special sheets such as thick paper sheets, coated sheets, and film sheets for which separation feeding is difficult.

[0014] The image forming unit 3 only needs to be configured to form an image on the sheet S sent from the feeding unit 2, and various image forming mechanisms can be adopted. In the illustrated embodiment, an electrostatic image forming mechanism is shown as the image forming unit 3. However, the image forming unit 3 is not limited to the illustrated electrostatic image forming mechanism, and an inkjet image forming mechanism, an offset image forming mechanism, etc. can also be adopted.

[0015] The image forming unit 3 shown in FIG. 1 is provided with a photoreceptor 9 formed in a drum shape or a belt shape, and a light emitter 10 that emits an optical beam to the photoreceptor 9. A developing unit 11 and a cleaner (not shown) are arranged around the rotating photoreceptor 9. The illustrated one is a monochrome printing mechanism. An electrostatic latent image is optically formed on the photoreceptor 9 by the light emitter 10, and toner is attached to this latent image by the developing unit 11. The toner image attached to the photoreceptor 9 is image-transferred to the sheet S sent from the feeding unit 2 by a transfer charger 12. After the image-transferred sheet S is fixed by a fixing roller 13, it is sent to a conveyance path 14. Further, a circulation path is provided below the conveyance path 14 in the image forming unit 3. After the sheet S from the conveyance path 14 is back-flipped to the front and back by a switchback path, it is sent to the registration roller pair 8 again, an image is formed on the back surface of the sheet S, and it is sent to the conveyance path 14. A discharge roller 15 (so-called discharge roller) is arranged in the conveyance path 14, and an opening 16 is formed at the end thereof. The sheet S is sent out from the opening 16 to a sheet processing device B described later by the discharge roller 15.

[0016] Above the image forming unit A1 configured as described above, an image reading unit A2 is provided for optically reading the document image to be formed by the image forming unit 3. Above the image reading unit A2, a document feeding unit A3 is mounted.

[0017] The image reading unit A2 includes a first platen 17 and a second platen 21 formed of transparent glass, a reading carriage 18, a light source mounted on the reading carriage 18, a photoelectric conversion element 19, and a reduction optical system 20 configured by combining mirrors and lenses. Then, the reading carriage 18 is scanned along the first platen 17, the light from the light source is irradiated onto the image of the document placed on the first platen 17, and the reflected light from the image of the document is guided to the photoelectric conversion element 19 by the reduction optical system 20 to read the image. The photoelectric conversion element 19 converts the image data into an electrical signal and transfers it to the image forming unit 3.

[0018] The document feeding unit A3 includes a feeding tray 22, a feeding path 23, and a stacking tray 24. The document placed on the feeding tray 22 is conveyed one by one along the feeding path 23, passed over the second platen 21, and sent out to the stacking tray 24. When reading the document fed from the document feeding unit A3 and passing over the second platen 21, the reading carriage 18 is stopped in advance below the second platen 21, and image data is generated from the image passing over the second platen 21.

[0019] [Overall Configuration of Sheet Processing Apparatus] Next, the overall configuration of the sheet processing device B that performs processing such as stapling and folding on the sheet sent from the image forming apparatus A will be described with reference to FIG. 2. FIG. 2 shows the detailed configuration of the sheet processing device B. The sheet processing device B can stack the sheets received from the receiving portion 26, which is the entrance of the straight path 28 connected to the opening 16 of the image forming apparatus A, after processing, on the first tray (first stacking tray) 49, the saddle stacking unit 131, and the second tray (second stacking tray) 71, which will be described later. Among the sheet processing device B, the portion other than the first tray 49 and the second tray 71 is defined as the processing unit 200. That is, the processing unit 200 includes the device housing 27, the straight path 28, the processing unit B1, and the saddle portion B2, which will be described later.

[0020] In the illustrated device, the sheets sent to the straight path 28 as the conveyance path and the first conveyance path are transferred from the processing unit B1, which will be described later, to the first tray 49 and the second tray 71, and from the saddle portion B2, which will be described later, to the saddle stacking unit 131. Each device has a control unit, a communication unit, etc., like the blocks showing the control configuration in the entire device shown in FIG. 3, and controls the device accordingly.

[0021] The processing unit B1 is disposed below the path exit (delivery portion 35) of the straight path 28, aligns and stacks a plurality of sheets sequentially delivered from the straight path 28 via the delivery portion 35 into a sheet bundle, and can perform binding processing, which is an example of a predetermined process, on the end of this sheet bundle. The bound sheet bundle is stacked on the first tray 49 as the stacking portion.

[0022] The saddle portion B2 is disposed below the delivery portion of the saddle path 32 as the second conveyance path that branches vertically downward from the straight path 28, aligns and stacks a plurality of sheets sequentially delivered from the straight path 28 via the saddle path 32 and the delivery portion into a sheet bundle, performs saddle stitching processing, or performs folding processing without performing saddle stitching processing, and then sends it out to the saddle stacking unit 131. Hereinafter, each configuration will be described in detail.

[0023] [Device housing] As shown in Fig. 2, the sheet processing device B includes a device housing 27, a straight path 28, a processing unit B1, a saddle section B2, a first tray 49 as a loading tray, a saddle loading unit 131, a second tray 71, etc. The straight path 28, the processing unit B1, and the saddle section B2 are arranged inside the device housing 27. Also, the straight path 28 has a sheet receiving section 26 and a sheet delivery section 35. The processing unit B1 and the saddle section B2 process the sheet delivered from the delivery section 35 of the straight path 28. The first tray 49, the saddle loading unit 131, and the second tray 71 load the sheets sent from each processing section. The illustrated device housing 27 is connected to the device housing 1 of the image forming device A located on the upstream side in the sheet conveyance direction in the straight path 28. And the device housing 27 and the device housing 1 are arranged so that the height from the installation surface of the opening 16 of the image forming device A and the receiving section 26 of the sheet processing device B is substantially the same, and the opening 16 and the receiving section 26 are connected.

[0024] [Sheet receiving path] As shown in Figs. 2 and 4, the straight path 28, which is a sheet receiving path, is configured as a substantially straight path that traverses the device housing 27 in a substantially horizontal direction, and includes a receiving section 26 that is continuous with the opening (main body opening) 16 of the image forming device A, and a delivery section 35 that is located on the opposite side across the device from this receiving section 26. In this straight path 28, sheet conveyance is possible in a first direction from the receiving section 26 toward the first discharge path 31, and conveyance is also possible in a second direction from the first discharge path 31 toward the receiving section 26. Entrance rollers 29, a first conveyance roller 201, a second conveyance roller (shift roller) 202, and a third conveyance roller (shift roller) 203, which are conveyance rollers, are arranged. That is, the entrance rollers 29, the first conveyance roller 201, the second conveyance roller 202, and the third conveyance roller 203 can convey the sheet in a first direction and a second direction opposite to this first direction in the conveyance path, and are arranged in order from the receiving section 26 side with respect to the first direction.

[0025] Note that the second conveyance roller 202 and the third conveyance roller 203 are also shift rollers capable of moving the sheet in the width direction (front-rear direction) of the sheet, which intersects the sheet conveyance direction. That is, the second conveyance roller 202 and the third conveyance roller 203 are movable in the width direction by a driving unit (not shown), and it is possible to shift the sheet to the front side or the rear side while sandwiching the sheet.

[0026] The first discharge path 31 is connected to the delivery portion 35 of the straight path 28, and a pre-processing roller 36 as a conveyance unit is arranged at this connection portion. The sheet delivered from the straight path 28 to the first discharge path 31 and sent out from the first discharge path 31 is sent out to the first tray 49 or guided to the processing unit B1. Note that each of the above-described conveyance rollers may be another member capable of conveying a sheet such as a conveyance belt.

[0027] [Layout of Sheet Receiving Path] As shown in FIGS. 2 and 4, a saddle path 32 and an upper conveyance path 30, which are branch paths, are connected to the straight path 28. The saddle path 32 and the upper conveyance path 30 are arranged in order from the receiving portion 26 toward the first discharge path 31 with respect to the first direction. Further, the saddle path 32 branches downward in the vertical direction from the straight path 28, and the upper conveyance path 30 branches upward in the vertical direction from the straight path 28. At each branching portion of the straight path 28 and the saddle path 32 and the upper conveyance path 30, a saddle path switching member 33 and an upper conveyance path switching member 34 as switching members for switching the conveyance direction of the conveyed sheet are arranged.

[0028] Note that a buffer path 39, which is a branch path branching downward in the vertical direction from the straight path 28, is connected between the second transport roller 202 and the third transport roller 203. The buffer path 39 as a buffer section is a path capable of temporarily waiting for the sheet. When buffering the sheet in the buffer path 39, the sheet transported downstream of the branch section of the buffer path 39 in the straight path 28 in the first direction is transported in the direction opposite to the first direction by reversely rotating the third transport roller 203 or the like, and is guided to the buffer path 39 by a switching member (not shown).

[0029] Then, this sheet is transported to the buffer path 39 by the transport roller 208, and the rotation of the transport roller 208 is stopped at the position where the rear end of the sheet has passed through the straight path 28. In this state, the next sheet can be transported downstream of the branch section of the buffer path 39 in the straight path 28 in the first direction. Further, in the present embodiment, by reversely rotating the transport roller 208, the sheet in the buffer path 39 can be transported toward the straight path 28, and these two sheets can be merged at the branch section. Furthermore, these two sheets can be stacked and transported by the third transport roller 203 and the pre-processing roller 36 as a buffer transport section.

[0030] [Path Branching] The upper transport path switching member 34 is composed of a switching member guide that moves so as to change the transport path so as to transport the sheet received from the receiving section 26 to either the first discharge path 31 or the upper transport path 30, and is connected to a drive section (not shown) such as an electromagnetic solenoid or a mini motor.

[0031] [Upper Transport Path] In the straight path 28, an upper conveyance path 30 (printout discharge path) for conveying sheets other than the sheet discharged to the first discharge path 31 is connected, and at the path branching portion, an upper conveyance path switching member 34 for guiding the sheet to the upper conveyance path 30 is provided. Further, the upper conveyance path 30 is provided with a fourth conveyance roller 204, a fifth conveyance roller 205, a sixth conveyance roller 206 as conveyance rollers for guiding the sheet to the second tray 71, and a second discharge roller pair 207 as a discharge portion. By these, the sheet guided to the upper conveyance path 30 is sent out from the upper conveyance path opening 40 to the second tray 71 (overflow tray) as a stacking tray (stacking portion) by the second discharge roller pair 207.

[0032] The processing unit B1 is arranged on the downstream side of the straight path 28 and includes a processing tray 37 as a placement portion for placing the sheets sent from the first discharge path 31 and aligning and stacking the plurality of placed sheets, and a binding processing mechanism (stapler) 47 as a processing portion for binding the stacked sheet bundle. Then, the processing unit B1 performs a binding process on the sheet bundle placed on the processing tray 37. The binding processing mechanism 47 is arranged vertically below the straight path 28. The binding processing mechanism 47 is movable in the width direction and can perform a binding process at a desired position in the width direction with respect to the sheet bundle placed on the processing tray 37. As shown in FIGS. 2 and 4, a step is formed in the first discharge path 31 and the processing tray 37 is arranged below it. Between the first discharge path 31 and the processing tray 37, a first switchback path for reversing the conveyance direction from the opening 31a of the first discharge path 31 and guiding the sheet onto the processing tray 37 is formed.

[0033] Specifically, the first discharge path 31 is provided with an upper conveyance roller 41 and a lower conveyance roller 48 for sandwiching and conveying a sheet. The upper conveyance roller 41 and the lower conveyance roller 48 constitute a discharge roller pair 42 as a discharge unit. The upper conveyance roller 41 can come into contact with and separate from the lower conveyance roller 48, and can convey in the direction (discharge direction) toward the first tray 49 with the upper conveyance roller 41 and the lower conveyance roller 48 sandwiching the sheet, and in the direction opposite to this direction. And, it can be conveyed by the upper conveyance roller 41 and the lower conveyance roller 48 via the first switchback path toward the processing tray 37. Further, the upper conveyance roller 41 and the lower conveyance roller 48 (that is, the discharge roller pair 42) send out the sheet or the sheet bundle on the processing tray 37 from the opening 31a to the first tray 49 as a stacking tray (stacking unit). The opening 31a is a portion opened above the lower conveyance roller 48 of the apparatus housing 27. Furthermore, the discharge roller pair 42 sends out the sheet conveyed to the first discharge path 31 without passing through the processing tray 37 from the opening 31a to the first tray 49.

[0034] The processing unit B1 has a rear end regulating portion 47a as a butting portion that abuts against the end (rear end) of the sheet to position the sheet. On the processing tray 37, a scraping portion 38 for conveying the sheet conveyed to the processing tray 37 by the upper conveyance roller 41 and the lower conveyance roller 48 toward the rear end regulating portion 47a is arranged. And, the binding mechanism 47 performs a binding process on the end of a sheet bundle composed of a plurality of sheets placed on the processing tray 37 and whose end position is regulated by the rear end regulating portion 47a. Further, the binding mechanism 47 has a sheet bundle unloading mechanism for unloading this sheet bundle to the first tray 49 after performing the binding process on the end of the sheet bundle.

[0035] Further, the processing unit B1 includes a pair of alignment plates 270 as shift members, a rear-end dropping member 44 as a sheet dropping portion, and a discharging member 45. The pair of alignment plates 270 move in the width direction (shift direction) of the sheet intersecting the first direction while being in contact with the edge along the conveyance direction (first direction) of the sheet placed on the processing tray 37, thereby moving the sheet conveyed by the pre-processing roller 36 in the width direction. Such a pair of alignment plates 270 are arranged to face each other in the width direction. Further, the pair of alignment plates 270 perform alignment in the width direction of the sheet by moving in the width direction and coming into contact with the widthwise edges of the sheet. Among the pair of alignment plates 270, the front-side alignment plate 270 is moved in the width direction by the alignment plate 1 moving motor M13, and the rear-side alignment plate 270 is moved in the width direction by the driving of the alignment plate 2 moving motor MT14, respectively.

[0036] The rear-end dropping member 44 is disposed above the processing tray 37 and moves in the vertical direction to abut against the upper surface on the upstream side in the conveyance direction of the sheet, and operates to drop the upstream end portion (rear end portion) of the sheet toward the processing tray 37. The discharging member 45 discharges the sheet bundle placed on the processing tray 37 to the first tray 49 by pushing the rear end of the sheet bundle.

[0037] Note that the binding processing unit B1 shown in FIG. 2 supports the sheet sent from the first discharge path 31 so as to straddle between the processing tray 37 and the first tray 49 on the downstream side thereof. That is, the sheet sent from the first discharge path 31 has its front end portion on the uppermost sheet of the first tray 49 on the downstream side and its rear end portion supported on the processing tray 37.

[0038] [Saddle path] The straight path 28 is connected to a saddle path 32 for conveying the sheet to the saddle portion B2 described above, and the path branching portion is provided with a saddle path switching member 33 for guiding the sheet to the saddle path 32. The sheet guided to the saddle portion B2 by the saddle path 32 is sent to the saddle loading unit 131 via the post-fold path guide 114, the second roller post-path guide 116, and the saddle discharge guide 124 in a substantially horizontal direction after the center folding process and the folding process. In the present embodiment, the saddle discharge guide 124 is used as an auxiliary guide for appropriately loading the sheet onto the saddle loading unit 131.

[0039] [Control Configuration] The schematic of the control configuration of the image forming system 1000 will be described with reference to FIG. 3. First, the image forming apparatus A includes a control unit 310, an operation unit 302, a conveyance control unit 303, an image processing unit 304, a drive unit 305, and a communication unit 306. The control unit 310 includes a CPU (Central Processing Unit) 311, a ROM (Read Only Memory) 312, and a RAM (Random Access Memory) 313. The CPU 311 controls each unit while reading a program corresponding to the control procedure stored in the ROM 312. Further, work data and input data are stored in the RAM 313, and the CPU 311 controls with reference to the data stored in the RAM 313 based on the above-described program and the like.

[0040] The operation unit 302 is an operation panel provided, for example, on the image forming apparatus A, which is connected to the control unit 310, and an operator operates the apparatus and makes various settings. The conveyance control unit 303 controls various conveyance rollers and switching members for switching conveyance paths that convey the sheet in the image forming apparatus A. The image processing unit 304 controls the image forming unit 3. The drive unit 305 controls various motors and power supplies. The communication unit 306 communicably connects the control unit 310 to an external device 301 such as a personal computer and the communication unit 321 of the sheet processing apparatus B.

[0041] The sheet processing apparatus B includes a stacker control unit 330, a conveyance control unit 322, an edge binding control unit 323, a discharge processing control unit 324, and a communication unit 321. The stacker control unit 330 has a CPU 331, a ROM 332, and a RAM 333, similar to the control unit 310. The conveyance control unit 322 controls various conveyance rollers that convey sheets and switching members that switch conveyance paths, except for the saddle portion B2 of the sheet processing apparatus B. The edge binding control unit 323 controls the processing unit B1. The discharge processing control unit 324 controls the discharge of sheets and various stacking trays on which the discharged sheets are stacked. The communication unit 321 communicably connects the communication unit 306 of the image forming apparatus A and the communication unit 341 of the saddle portion B2 to the stacker control unit 330. Note that the communication between the communication unit 306 and the communication unit 321 may be performed by wired communication or wireless communication.

[0042] Note that the communication unit 321 functions as a notification unit and, as will be described later, when it is detected that there are sheets on stacking trays such as the first tray 49 and the second tray 71, it notifies that there are sheets. Specifically, it transmits information indicating that there are sheets to the communication unit 306 of the image forming apparatus A and causes, for example, the display unit of the operation unit 302 to display that there are sheets.

[0043] The saddle portion B2 includes a saddle control unit 350, a conveyance control unit 342, a middle binding control unit 343, a middle folding control unit 344, and a communication unit 341. The saddle control unit 350 has a CPU 351, a ROM 352, and a RAM 353, similar to the control unit 310. The conveyance control unit 342 controls various conveyance rollers that convey sheets and switching members that switch conveyance paths in the saddle portion B2. The middle binding control unit 343 controls the middle binding processing unit 104. The middle folding control unit 344 controls the middle folding mechanism C1. The communication unit 341 communicably connects the communication unit 321 of the sheet processing apparatus B to the saddle control unit 350.

[0044] [Saddle Portion] As shown in FIG. 2, the saddle portion B2 has a center folding processing mechanism C1. The center folding processing mechanism C1 aligns and stacks the sheets sent from the straight path 28 into a sheet bundle, performs a binding process on the central portion in the conveyance direction of the sheet and the bundle, and performs a center folding process of folding the sheet bundle at the bound position. And a saddle loading unit 131 is arranged on the downstream side of the center folding processing mechanism C1 to store the sheet bundle subjected to the bookbinding process. Note that it is also possible to perform only a center folding process of aligning and stacking one or more sheets and folding the central portion in the conveyance direction without performing the center binding process.

[0045] [Sheet Loading Device] Details of the sheet loading device 400 included in the sheet processing device B of the present embodiment will be described with reference to FIGS. 5 to 13. The sheet loading device 400 stacks sheets that have been subjected to a predetermined process (in this embodiment, a binding process) by a binding processing mechanism 47 as a processing unit or sheets that have not been subjected to a predetermined process. The sheet loading device 400 includes a discharge roller pair 42 (an upper conveyance roller 41 and a lower conveyance roller 48) as a discharge unit, a first tray 49 as a loading tray, a tray elevating motor MT18 as an elevating unit, a pair of alignment plates (joggers) 401 and 402 as a pair of alignment members, a jogger 1 moving motor MT20 and a jogger 2 moving motor MT21 as alignment member moving units, and the like.

[0046] The tray elevating motor MT18 (FIG. 5) elevates the first tray 49. The pair of alignment plates 401 and 402 are located on both sides in the width direction of the sheet intersecting the discharge direction of the sheet by the upper conveyance roller 41 and the lower conveyance roller 48 with respect to the uppermost sheet stacked on the first tray 49, and perform alignment in the width direction of the uppermost sheet. The jogger 1 moving motor MT20 as a first moving unit moves the front-side alignment plate 401 in the width direction. The jogger 2 moving motor MT21 as a second moving unit moves the rear-side alignment plate 402 in the width direction. That is, in the present embodiment, the pair of alignment plates 401 and 402 can be independently moved in the width direction.

[0047] Here, the relationship between the drive motors and various sensors of a part of the configuration of the sheet processing device B around the sheet loading device 400 will be described with reference to the block diagram of FIG. 5. The various motors are controlled by the stacker control unit 330 as the control unit, and the signals of the various sensors are sent to the stacker control unit 330. The stacker control unit 330 controls the driving of the various motors based on the signals of the various sensors.

[0048] First, the inlet conveyance motor MT1 drives the inlet roller 29, the conveyance motor MT2 drives the first conveyance roller 201, the shift 1 conveyance motor MT3 drives the second conveyance roller (shift roller) 202, the shift 2 conveyance motor MT4 drives the third conveyance roller (shift roller) 203, and the pre - processing conveyance motor MT5 drives the pre - processing roller 36. These are all motors that can be rotationally driven in both forward and reverse directions. Also, the discharge roller 1 motor MT6 is a motor that can rotationally drive the upper conveyance roller 41 in both forward and reverse directions. Note that the discharge roller 1 motor MT6 also rotationally drives the paddle 275 described later. The discharge roller 2 motor MT7 is a motor that can rotationally drive the lower conveyance roller 48 in both forward and reverse directions. The buffer conveyance motor MT8 is a motor that can rotationally drive the conveyance roller 208 that conveys the sheet in the above - mentioned buffer path 39 in both forward and reverse directions.

[0049] Also, the shift 1 motor MT9 is a motor that moves the second conveyance roller 202 in the width direction, and the shift 2 motor MT10 is a motor that moves the third conveyance roller 203 in the width direction. The discharge roller swing motor MT11 is a motor that swings the upper conveyance roller 41 in the vertical direction so that it can come into contact with and separate from the lower conveyance roller 48 as described above. The rear - end drop drive motor MT12 is a motor that moves the rear - end drop member 44 in the vertical direction. The alignment plate 1 movement motor M13 and the alignment plate 2 movement motor MT14 are motors that move the pair of alignment plates 270 that perform sheet alignment in the processing tray 37 in the width direction as described above.

[0050] Further, the stapler movement motor MT15 is capable of moving the stapling mechanism 47 in the width direction. The stapler motor MT16 is a motor that drives the stapling mechanism 47 to perform stapling. The bundle delivery motor MT17 is a motor that drives the bundle delivery member 45. The tray lifting motor MT18 is a motor that raises and lowers the first tray 49. The jogger lifting motor MT19 is a motor that raises and lowers a pair of alignment plates (joggers) 401 and 402 as will be described later. In the present embodiment, the alignment plates 401 and 402 are raised and lowered by one motor, but the alignment plates 401 and 402 may be raised and lowered by separate motors. The jogger 1 movement motor MT20 and the jogger 2 movement motor MT21 move the pair of alignment plates 401 and 402 in the width direction, respectively, as described above. The paddle lifting motor MT22 is a motor that raises and lowers a paddle 275 to be described later.

[0051] Next, various sensors will be described. As shown in FIG. 4, the entrance sensor SN1 is provided at the entrance of the straight path 28 and detects a sheet delivered from a device (in the present embodiment, the image forming device A) connected to the upstream side of the sheet processing device B to the sheet processing device B. As shown in FIGS. 6 and 7, the registration detection sensor SN2 is disposed on the upstream side in the conveyance direction of the second conveyance roller 202 which is a shift roller, and detects the position of the sheet in the width direction. As shown in FIG. 4, the sheet edge detection sensor SN3 is disposed on the upstream side in the conveyance direction of the pre-processing roller 36 and detects the sheet. The stacker control unit 330 determines that the rear end of the sheet has passed through the discharge roller pair 42 after a predetermined time has elapsed since the rear end of the sheet has passed through the sheet edge detection sensor SN3.

[0052] The shift roller 1 HP detection sensor SN4 detects the home position (HP) in the width direction of the second transport roller 202. The shift roller 2 HP detection sensor SN5 detects the home position (HP) in the width direction of the third transport roller 203. The jogger lift HP detection sensor SN6 detects the home position (HP) in the lift direction of the pair of alignment plates 401 and 402. The jogger 1 HP detection sensor SN7 detects the home position (HP) in the width direction of the front alignment plate 401. The jogger 2 HP detection sensor SN8 detects the home position (HP) in the width direction of the rear alignment plate 402. As will be described later, the pair of alignment plates 401 and 402 are each movable in the width direction. The home positions in the lift direction and width direction of the pair of alignment plates 401 and 402 are the positions shown in FIGS. 6 and 7.

[0053] The paddle lift HP detection sensor SN9 detects the home position (HP) in the lift direction of the paddle 275. The home position of the paddle 275 is the position shown in FIGS. 6 and 7. The sheet upper surface detection sensor SN10 detects the upper surface of the sheet on the first tray 49. In this embodiment, the sheet upper surface detection sensor SN10 also detects the presence or absence of a sheet on the first tray 49. The sheet removal detection sensor SN11 is a sensor for detecting that a stack of sheets is loaded on the first tray 49 and the stack of sheets has been suddenly removed while the first tray 49 is in the lowered state.

[0054] Next, with reference to FIGS. 6 and 7, the configuration from the first transport roller 201 to the first tray 49 of the sheet processing apparatus B will be described. FIGS. 6 and 7 are a cross-sectional view and a top view of a state in which the pair of alignment plates 401 and 402 and the paddle 275 are in the home position. Since the configuration from the first transport roller 201 to the discharge roller pair 42 is as described above, hereinafter, the sheet loading device 400, which is the configuration around the first tray 49, will be described.

[0055] The first tray 49 stacks the sheets discharged from the opening 31a of the first discharge path 31. Among the outer surfaces of the apparatus housing 27, below the opening 31a and between the first tray 49 and the processing unit B1, there is provided a butting member 271 against which the rear end (the upstream end with respect to the discharge direction) of the discharged sheet abuts. This butting member 271 serves to align the conveyance direction of the sheets discharged and stacked on the first tray 49. The loading surface 49a, which is the upper surface of the first tray 49, gently slopes downward toward the butting member 271. That is, the loading surface 49a on which the sheets of the first tray 49 are stacked is inclined at a first angle with respect to the horizontal direction so as to rise upward as it goes downstream in the discharge direction. The sheet discharged from the opening 31a onto the loading surface 49a slides down along the inclination of the loading surface 49a after falling onto the first tray 49, and eventually the rear end of the sheet reaches the butting member 271 and stops.

[0056] The first tray 49 moves up and down in the vertical direction via a lifting mechanism (not shown) by a tray lifting motor MT18. That is, when discharging the sheets to the first tray 49 or the second tray 71, it is necessary to move the first tray 49 or the second tray 71 up and down so as to keep the position of the loading surface 49a or the topmost sheet on the loading surface 49a constant so that the alignment of the stacked sheets does not deteriorate. For this purpose, in the present embodiment, the tray lifting motor MT18 as a lifting unit lowers the first tray 49 or the second tray 71 so that the height of the topmost sheet of the sheets discharged by the discharge roller pair 42 or the second discharge roller pair 207 and stacked on the first tray 49 or the second tray 71 falls within a predetermined range, and when the sheets stacked on the first tray 49 or the second tray 71 are removed, the first tray 49 or the second tray 71 is raised.

[0057] Above the first tray 49, a pair of alignment plates 401 and 402 for aligning the width direction of the sheet that intersects the discharge direction of the sheet, and a paddle 275 for aligning the discharge direction of the sheet are arranged. The pair of alignment plates 401 and 402 are movable in the vertical direction and also movable in the width direction. That is, the pair of alignment plates 401 and 402 can be moved up and down by a jogger lift motor MT19 as an alignment member lift part to a first position where the topmost sheet on the first tray 49 can be aligned, and a second position above the first position and not interfering with the sheet discharged from the discharge roller pair 42. Also, the pair of alignment plates 401 and 402 can be moved by a jogger 1 movement motor MT20 and a jogger 2 movement motor MT21 as an alignment member movement part to an alignment position for aligning the width direction of the topmost sheet and a position separated from the topmost sheet in the width direction from the alignment position. Note that the position separated from the topmost sheet in the width direction from the alignment position is, for example, the sheet receiving position described later.

[0058] On the loading surface 49a of the first tray 49, recesses 49b that can be entered when the pair of alignment plates 401 and 402 descend are formed. FIGS. 6 and 7 show a state where the pair of alignment plates 401 and 402 are in a second position retracted above the nip point N1 of the upper conveying roller 41 and the lower conveying roller 48, and in this state, the sheet is discharged from the opening 31a. Then, when the sheet is discharged onto the first tray 49, the pair of alignment plates 401 and 402 descend to the first position where a part enters the recess 49b, and by moving in the width direction from the sheet receiving position to the alignment position, the both ends in the width direction of the sheet are tapped from both sides in the width direction of the sheet. Thereby, the width direction alignment of the sheet is performed.

[0059] On the one hand, the paddle 275 is movable in the vertical direction and can convey the sheet on the first tray 49 in a direction opposite to the discharge direction by rotating. That is, the paddle 275 can move to a conveyance position where it contacts the sheet on the first tray 49 and conveys the sheet upstream with respect to the sheet discharge direction, and a retracted position where it is retracted above the conveyance position. FIGS. 6 and 7 show a state where the paddle 275 is retracted above the opening 31a (in the retracted position), and in this state, the sheet is discharged from the opening 31a. Then, when the sheet is discharged onto the first tray 49, the paddle 275 descends toward the conveyance position, and by rotating the paddle 275, the sheet discharged from the opening 31a is conveyed toward the abutting member 271 while being dropped onto the first tray 49.

[0060] [Alignment plate] Next, with reference to FIGS. 8 and 9, the configuration of the pair of alignment plates 401 and 402 will be described. The pair of alignment plates 401 and 402 are each supported via a pair of swing arms 403 and 404 so as to be swingable in the vertical direction with respect to the swing shaft 405. The pair of swing arms 403 and 404 and the swing shaft 405 will be described later.

[0061] FIG. 8 is a perspective view of the periphery of the pair of alignment plates 401 and 402 in a state where the pair of alignment plates 401 and 402 are in the home position (second position), and FIG. 9 is a perspective view of the periphery of the pair of alignment plates 401 and 402 in a state where the pair of alignment plates 401 and 402 have descended from the second position to the first position. The state in FIG. 9 is a state where the pair of alignment plates 401 and 402 are simply lowered from the second position to the first position, but the postures of the pair of alignment plates 401 and 402, that is, the angles of the second virtual line α2 (FIG. 19(a)) with respect to the horizontal direction described later, are the same as the postures in the alignment position.

[0062] The pair of alignment plates 401 and 402 each have an alignment surface 4001, a guide surface 4002 as a guide portion, and a sheet receiving surface 4003 as an upstream guide portion. Note that the configuration of the alignment plates 401 and 402 is only arranged such that the alignment surfaces 4001 for aligning the sheets face each other, and since the basic configuration is the same, hereinafter, the alignment plate 401 will be representatively labeled and described.

[0063] The alignment plates 401 and 402 each have a first portion 4001a on the downstream side with respect to the discharge direction of the sheet by the discharge roller pair 42, and a second portion 4001b on the upstream side of the first portion 4001a. The width of the first portion 4001a in the vertical direction is larger than the width of the second portion 4001b in the vertical direction. Also, the upper end portions of the first portion 4001a and the second portion 4001b are located in a straight line and are continuous with a guide surface 4002 to be described later.

[0064] On the other hand, the lower end of the first portion 4001a is inclined such that a part on the downstream side with respect to the discharge direction goes upward as it goes downstream, and the upstream side of this part is inclined upward as it goes upstream. And the lower end of the second portion 4001b is continuous with the lower end of the upstream side portion of the first portion 4001a, and further, at a larger inclination angle than this upstream side portion, it is inclined upward as it goes upstream in the discharge direction. Thereby, the width of the first portion 4001a of the alignment surface 4001 in the vertical direction is made larger than the width of the second portion 4001b. And the first portion 4001a of the alignment surface 4001 can be brought into contact with or opposed to the widthwise edge of the sheet on the first tray 49 in a wide range in the vertical direction. Incidentally, the recess 49b of the first tray 49 described above has a shape corresponding to the shape of the lower end portions of the alignment plates 401 and 402 so that the lower end portions can enter.

[0065] The guide surface 4002 is a surface that guides the next sheet above the alignment surface 4001 that aligns the top sheet when the next sheet is discharged from the discharge roller pair 42 in a state where it is displaced in the width direction with respect to the top sheet during alignment of the pair of alignment plates 401 and 402 at the alignment position. The guide surface 4002 is formed on the upper surfaces of the pair of alignment plates 401 and 402 in a state where the pair of alignment plates 401 and 402 are in the alignment position. The loading surface 49a of the first tray 49 is inclined at a first angle with respect to the horizontal direction so as to go upward as it goes downstream in the discharge direction, as described above. On the other hand, the guide surface 4002 is inclined at a second angle larger than the first angle with respect to the horizontal direction so as to go upward as it goes downstream in the discharge direction at the alignment position.

[0066] Also, as shown in FIG. 19(a) described later, which shows a state where the alignment plates 401 and 402 are in the alignment position, the upstream end portion of the guide surface 4002 in the discharge direction is below the nip line N2, which is a line obtained by extending the nip surface of the upper conveyance roller 41 and the lower conveyance roller 48, which are a pair of discharge rollers, downstream in the discharge direction in a state where the pair of alignment plates 401 and 402 are in the alignment position. The nip line N2 is in the same direction as the discharge direction of the sheet by the discharge roller pair 42. Therefore, the downstream end (front end) of the sheet discharged from the discharge roller pair 42 can more easily pass above the upstream end portion of the guide surface 4002. When the angle of the nip line N2 with respect to the horizontal direction is large, the upstream end portion of the guide surface 4002 may be positioned above the nip point N1. However, in order to prevent the front end of the discharged sheet from being easily caught by the upstream end portion of the guide surface 4002, it is preferable that the upstream end portion of the guide surface 4002 is positioned below the nip point N1 with respect to the vertical direction.

[0067] As described above, in the present embodiment, the angle of the guide surface 4002 with respect to the horizontal direction is made larger than the angle of the loading surface 49a with respect to the horizontal direction. For this reason, the vertical width of the first portion 4001a of the alignment surface 4001 can be ensured, and the position of the upstream end portion of the guide surface 4002 can be easily positioned below the nip line N2, more preferably below the nip point N1. As a result, the sheet can be aligned over a wide range of the alignment surface 4001, and the discharged sheet can be less likely to be caught by the upstream end portion of the guide surface 4002. If the sheet can be aligned over a wide range of the alignment surface 4001, the sheet loading amount of the first tray 49 that can be aligned by the alignment plates 401 and 402 can be increased.

[0068] The sheet receiving surface 4003 as the upstream guide portion is provided at the upstream end portion in the discharge direction of the guide surface 4002 in a state where the pair of alignment plates 401 and 402 are in the alignment position, and is inclined so as to face inward on the side where the top sheet is located in the width direction as it goes downstream in the discharge direction, and is a surface for guiding the next sheet discharged from the discharge roller pair 42 to the guide surface 4002. That is, the sheet receiving surface 4003 has a role of receiving the tip of the sheet discharged from the discharge roller pair 42 onto the guide surface 4002 so as to scoop it up in a state where the pair of alignment plates 401 and 402 are in the alignment position.

[0069] Such a sheet receiving surface 4003 is inclined so as to face downward as it goes inward in the width direction in a state where the pair of alignment plates 401 and 402 are in the alignment position. Thereby, for example, even if a sheet with low stiffness is discharged so as to hang down from the discharge roller pair 42, the tip of this sheet can be easily scooped up by the sheet receiving surface 4003. For example, if the position of the upstream end portion of the guide surface 4002 is close to the discharge roller pair 42 and the position of the upstream end portion of the guide surface 4002 is sufficiently lower than the nip point N1, and the sheet discharged from the discharge roller pair 42 easily passes over the guide surface 4002, the sheet receiving surface 4003 may be omitted.

[0070] In this embodiment, since the guide surfaces 4002 are provided on the pair of alignment plates 401 and 402 in this way, as will be described later, even if the next sheet is discharged while the pair of alignment plates 401 and 402 are aligning the sheet, the next sheet can be guided by the guide surface 4002. If there is no such guide surface 4002, when the next sheet is discharged with the alignment plates 401 and 402 in the alignment position, the next sheet may collide with one of the alignment plates, disturbing the posture of the sheet or causing the sheet to bend. In particular, as will be described later, in order to increase productivity, when the interval between the continuously discharged sheets is narrowed, the sheets will be discharged with the alignment plates 401 and 402 in the alignment position. In this embodiment, since there is the guide surface 4002 for guiding the sheet discharged from the discharge roller pair 42 with the alignment plates 401 and 402 in the alignment position as described above, it is possible to reduce the collision of the sheet with one of the alignment plates. The operation of the alignment plates 401 and 402 during sheet discharge will be described later.

[0071] [Drive Configuration of Alignment Plate and Paddle] Next, with reference to FIGS. 8 to 11, the drive configuration of the pair of alignment plates 401 and 402 and the paddle 275 will be described. FIGS. 8 and 10 are perspective views of the periphery of the pair of alignment plates 401 and 402 with the pair of alignment plates 401 and 402 in the home position, and FIGS. 9 and 11 are perspective views of the periphery of the pair of alignment plates 401 and 402 with the pair of alignment plates 401 and 402 lowered from the home position to the first position. Also, in FIGS. 8 and 9, the jogger lift HP detection sensor SN6 and the paddle lift HP detection sensor SN9 are omitted for the sake of explanation, while in FIGS. 10 and 11, the jogger lift HP detection sensor SN6 and the paddle lift HP detection sensor SN9 are also shown.

[0072] The alignment plate 401 on the front side (the upper right side in FIGS. 8 to 11) moves in the width direction by the front side movement mechanism 410, and the alignment plate 402 on the rear side (the lower left side in FIGS. 8 to 11) moves in the width direction by the rear side movement mechanism 420. Further, the pair of alignment plates 401 and 402 move in the vertical direction by the alignment plate lifting mechanism 430, and the paddle 275 moves in the vertical direction by the paddle lifting mechanism 440. Such a pair of alignment plates 401 and 402 are supported via a pair of swing arms 403 and 404 so as to be swingable in the vertical direction with respect to the swing shaft 405, and the paddle 275 is supported via the paddle arm 276 so as to be swingable in the vertical direction with respect to the swing shaft 405.

[0073] The swing shaft 405 is arranged across the width direction above the pair of discharge rollers 42. The position of the swing shaft 405 with respect to the discharge direction is a position as close as possible to the pair of discharge rollers 42. In the present embodiment, it is located further upstream than the upstream end in the discharge direction of the recess 49b of the first tray 49. The pair of swing arms 403 and 404 can swing in the vertical direction about the swing shaft 405 arranged above the pair of discharge rollers 42 by being driven by the jogger lift motor MT19 as an alignment member lifting unit. Specifically, when the drive of the jogger lift motor MT19 is transmitted to the pair of swing arms 403 and 407 via the alignment plate lifting mechanism 430, the pair of swing arms 403 and 407 swing in the vertical direction about the swing shaft 405. The pair of alignment plates 401 and 402 are arranged inside the pair of swing arms 403 and 404 on the side where the top sheet is located with respect to the width direction, and are rotatably connected to the pair of swing arms 403 and 404.

[0074] The pair of swing arms 403 and 404 are supported so as to be rotatable with respect to the swing shaft 405 and movable relative to each other along the axial direction. Therefore, the swing arms 403 and 404 do not swing only by the rotation of the swing shaft 405. For this reason, the sheet loading device 400 has an alignment plate lifting mechanism 430 as a drive transmission unit. The alignment plate lifting mechanism 430 transmits the drive of the jogger lift motor MT19 to swing the swing arms 403 and 404 about the swing shaft 405, and has a transmission mechanism 431, parallel shafts 432, a connecting portion 433, and an engagement hole 434 as an engagement portion.

[0075] The transmission mechanism 431 includes a gear 431a to which drive is transmitted from the drive gear of the jogging lifting motor MT19, a pulley (not shown) that rotates integrally with the gear 431a, a pulley 431b fixed to the swing shaft 405, and a belt 431c stretched between the pulley on the gear 431a side and the pulley 431b. The driving force of the jogging lifting motor MT19 is transmitted to the swing shaft 405 via the gear 431a, the pulley (not shown), the belt 431c, and the pulley 432b.

[0076] The parallel shafts 432 are provided parallel to the swing shaft 405 and are connected to the swing shaft 405 by the connecting portions 433. In the present embodiment, the parallel shafts 432 are respectively arranged on the front side and the rear side of the paddle 275, and each parallel shaft 432 is connected to the swing shaft 405 by the connecting portion 433. Therefore, the pair of parallel shafts 432 rotate about the swing shaft 405 as the swing shaft 405 rotates. The engaging holes 434 are respectively provided in the pair of swing arms 403 and 404, and when the parallel shaft 432 engages with the engaging holes 434 and rotates about the swing shaft 405, the pair of swing arms 403 and 404 are rotated together with the parallel shaft 432. As a result, the pair of alignment plates 401 and 402 respectively supported by the pair of swing arms 403 and 404 move in the vertical direction.

[0077] Such an engaging hole 434 is a through hole through which the parallel shaft 432 can be inserted and in which the parallel shaft 432 and the swing arms 403 and 404 can relatively move within a predetermined range with respect to the rotational direction about the swing shaft 405. That is, the engaging hole 434 is a through hole having a shape curved in a direction along an arc centered on the swing shaft 405, and the inserted parallel shaft 432 can relatively move within a predetermined range in the direction along this arc. The parallel shaft 432 inserted into the engaging hole 434 engages with the upstream end portion in the discharge direction of the engaging hole 434 at the home position (second position) in FIG. 8 due to the self-weight of the swing arms 403 and 404. Also, at the first position shown in FIG. 9, the parallel shaft 432 inserted into the engaging hole 434 engages with the upstream end portion in the discharge direction of the engaging hole 434 due to the self-weight of the swing arms 403 and 404.

[0078] However, for example, when descending from the second position to the first position, if the pair of alignment plates 401 and 402 contact the sheet or sheet bundle on the first tray 49 before reaching the first position, the pair of alignment plates 401 and 402 and the pair of swing arms 403 and 404 will be in a lifted state rather than the state when they are in the first position. At this time, if the parallel shaft 432 and the pair of swing arms 403 and 404 are connected so as not to be relatively movable in the rotational direction, the jogger lifting and lowering motor MT19 will be driven by the amount of movement until the pair of alignment plates 401 and 402 reach the first position, and the sheet on the first tray 49 may be damaged by the pair of alignment plates 401 and 402. On the other hand, as described above, by making the parallel shaft 432 and the engagement hole 434 relatively movable within a predetermined range in the rotational direction, even if the pair of alignment plates 401 and 402 contact the sheet, the parallel shaft 432 moves within the engagement hole 434, and the amount of movement of the pair of alignment plates 401 and 402 as described above can be absorbed. As a result, it is possible to suppress damage to the sheet on the first tray 49.

[0079] The paddle 275 is rotatably supported at the tip of the paddle arm 276. The paddle arm 276 is rotatably supported with respect to the swing shaft 405. Therefore, the paddle arm 276 does not swing only by the rotation of the swing shaft 405. For this reason, the sheet loading device 400 has a paddle lifting and lowering mechanism 440. The paddle lifting and lowering mechanism 440 transmits the drive of the paddle lifting and lowering motor MT22 to swing the paddle arm 276 around the swing shaft 405. The drive is transmitted from the drive gear 441 of the paddle lifting and lowering motor MT22 to the gear 442, the pulley 443 that rotates integrally with the gear 442, the pulley 444 that is rotatably supported by the swing shaft 405 and fixed to the paddle arm 276, and the belt 445 that is wound around the pulley 443 and the pulley 444. The driving force of the paddle lifting and lowering motor MT22 is transmitted to the paddle arm 276 via the drive gear 441, the gear 442, the pulley 443, the belt 445, and the pulley 444. When the paddle arm 276 swings around the swing shaft 405, the paddle 275 supported at the tip of the paddle arm 276 moves in the vertical direction between the above-described conveyance position and the retracted position.

[0080] This paddle 275 is rotationally driven by a discharge roller 1 motor MT6 (not shown in FIGS. 8 to 11) via a paddle drive mechanism 450. That is, in the present embodiment, the drive sources of the upper conveyance roller 41 and the paddle 275 are common. For this reason, while the upper conveyance roller 41 is rotationally driven, the paddle 275 is also rotating. Note that the rotational drive of the paddle 275 may be performed by a single motor. The paddle drive mechanism 450 transmits the drive of the discharge roller 1 motor MT6 to rotate the paddle 275, and includes a first transmission part 451 to which the drive is transmitted from the drive shaft of the discharge roller 1 motor MT6, a transmission shaft 452 to which the drive is transmitted from the first transmission part 451, a second transmission part 453 to which the drive is transmitted from the transmission shaft 452, and a third transmission part 454 that transmits the drive transmitted to the second transmission part 453 to the paddle 275.

[0081] The first transmission part 451, the second transmission part 453, and the third transmission part 454 are each composed of various power transmission members such as gears, pulleys, and belts. The first transmission part 451 is disposed on the rear side of the swing shaft 405 in the width direction, and the second transmission part 453 and the third transmission part 454 are disposed between a pair of alignment plates 401 and 402 in the width direction. The transmission shaft 452 is disposed above the swing shaft 405 and parallel to the swing shaft 405, and connects the first transmission part 451 and the second transmission part 453 so that drive can be transmitted therebetween. An output pulley 453a that outputs the drive input to the second transmission part 453 and an input pulley 454a to which the drive is input to the third transmission part 454 are integrated, and a belt 454c is wound between the input pulley 454a of the third transmission part 454 and a pulley 454b fixed to the rotation shaft of the paddle 275. The output pulley 453a and the input pulley 454a are supported so as to be relatively rotatable with respect to the swing shaft 405. With this configuration, the driving force of the discharge roller 1 motor MT6 input to the first transmission part 451 from the rear side is transmitted to the paddle 275 via the transmission shaft 452, the second transmission part 453, and the third transmission part 454, and the paddle 275 rotates.

[0082] As described above, the front alignment plate 401 moves in the width direction by the front side movement mechanism 410, and the rear alignment plate 402 moves in the width direction by the rear side movement mechanism 420. Further, the pair of alignment plates 401 and 402 are supported so as to be movable in the width direction with respect to the swing shaft 405 via the pair of swing arms 403 and 404. The configurations of the front side movement mechanism 410 and the rear side movement mechanism 420 are the same. The front side movement mechanism 410 includes a gear 412 to which the drive of the drive gear 411 of the jogger 1 movement motor MT20 is transmitted, a pulley 413 that rotates integrally with the gear 412, a pair of pulleys 414 disposed outside the movement range of the alignment plate 401 in the width direction with respect to the direction parallel to the swing shaft 405, a belt 415 wound around the pulley 413 and the pair of pulleys 414, and a tension pulley 416 that applies tension to the belt 415. Among the belt 415, the portion wound around the pair of pulleys 414 is parallel to the swing shaft 405, and a slide member 435 is fixed to a part of the portion of the belt 415 parallel to the swing shaft 405. The slide member 435 is movable in the width direction together with the swing arm 403, but is connected to the swing arm 403 so as to be relatively rotatable so that it does not rotate even when the swing arm 403 rotates about the swing shaft 405. Therefore, due to the rotational drive of the jogger 1 movement motor MT20, the portion of the belt 415 parallel to the swing shaft 405 moves parallel to the swing shaft 405, and the swing arm 403 fixed to this portion moves in the width direction along the swing shaft 405. Since the alignment plate 401 is supported by the swing arm 403, the alignment plate 401 moves in the width direction together with the swing arm 403.

[0083] Similarly, the rear movement mechanism 420 includes a gear 422 to which the drive of the drive gear 421 of the jogger 2 movement motor MT21 is transmitted, a pulley 423 that rotates integrally with the gear 422, a pair of pulleys 424 disposed outside the movement range in the width direction of the alignment plate 402 with respect to the direction parallel to the swing shaft 405, a belt 425 wound around the pulley 423 and the pair of pulleys 424, and a tension pulley 426 that applies tension to the belt 425. Among the belt 425, the portion wound around the pair of pulleys 424 is parallel to the swing shaft 405, and a slide member 435 is fixed to a part of the portion of the belt 425 parallel to the swing shaft 405. The slide member 435 is movable in the width direction together with the swing arm 404, and is connected to the swing arm 404 so as to be relatively rotatable so that it does not rotate even when the swing arm 404 rotates about the swing shaft 405. Therefore, due to the rotational drive of the jogger 2 movement motor MT21, the portion of the belt 425 parallel to the swing shaft 405 moves parallel to the swing shaft 405, and the swing arm 404 fixed to this portion moves in the width direction along the swing shaft 405. Since the alignment plate 402 is supported by the swing arm 404, the alignment plate 402 moves in the width direction together with the swing arm 404.

[0084] With such a configuration, the pair of alignment plates 401 and 402 can move independently in the width direction by the drive of the jogger 1 movement motor MT20 and the jogger 2 movement motor MT21. Note that the pair of alignment plates 401 and 402 may be moved in the width direction synchronously by one motor. Also, the parallel shafts 432 for moving the pair of alignment plates 401 and 402 in the vertical direction are arranged parallel to the swing shaft 405, and the engagement holes 434 provided in the swing arms 403 and 404 are through holes through which the parallel shafts 432 are inserted. Therefore, when the pair of alignment plates 401 and 402 move, the engagement holes 434 engage with the parallel shafts 432 while allowing the pair of alignment plates 401 and 402 to move in the width direction. Also, since the engagement holes 434 and the parallel shafts 432 are engaged regardless of the positions of the pair of alignment plates 401 and 402 in the width direction, the pair of alignment plates 401 and 402 can move in the vertical direction at any position in the width direction.

[0085] [Regarding the sensors around the integration board] Next, with reference to FIGS. 10 and 11, the jogger lift HP detection sensor SN6, jogger 1HP detection sensor SN7, jogger 2HP detection sensor SN8, and paddle lift HP detection sensor SN9 for detecting the positions of the integration boards 401 and 402 in the width direction and lift direction, and the position of the paddle 275 in the lift direction will be described. Each of these sensors is a photo interrupter including a light emitting part and a light receiving part that faces the light emitting part and receives the light emitted from the light emitting part. When a flag enters between the light emitting part and the light receiving part and blocks the light from the light emitting part, the sensor turns ON.

[0086] First, a flag 406 is fixed to the swing shaft 405 or the pulley 431b. Also, a jogger lift HP detection sensor SN6 is provided at a position where the flag 406 passes. When the jogger lift motor MT19 is rotationally driven to raise and lower the pair of integration boards 401 and 402, this driving force is transmitted to the swing shaft 405 via the integration board lift mechanism 430, and the flag 406 also rotates together with the swing shaft 405. FIG. 10 shows a state where the pair of integration boards 401 and 402 are in the home position, that is, the second position in the lift direction. In this state, the flag 406 does not enter the jogger lift HP detection sensor SN6, and the sensor is in the OFF state. The stacker control unit 330 determines in this state that the pair of integration boards 401 and 402 are in the home position in the lift direction.

[0087] Then, when the pair of integration boards 401 and 402 start to descend from the second position, the flag 406 enters the jogger lift HP detection sensor SN6, and the sensor becomes ON. Further, even when the pair of integration boards 401 and 402 descend and reach the first position shown in FIG. 11, the flag 406 remains in the state of entering the jogger lift HP detection sensor SN6. The stacker control unit 330 determines that the pair of integration boards 401 and 402 are in the first position, for example, by driving the jogger lift motor MT19 for a predetermined number of pulses or a predetermined time after the flag 406 enters the jogger lift HP detection sensor SN6.

[0088] Next, among the belts 415 for moving the front alignment plate 401 in the width direction, a flag 417 is fixed to a slide member 435 fixed to a portion wound around a pair of pulleys 414, and a flag 427 is fixed to a slide member 435 fixed to a portion wound around a pair of pulleys 424 among the belts 425 for moving the rear alignment plate 402 in the width direction. Further, at positions where the flags 417 and 427 pass, a jogger 1 HP detection sensor SN7 and a jogger 2 HP detection sensor SN8 are provided, respectively. When the jogger 1 moving motor MT20 is rotationally driven to move the front alignment plate 401 in the width direction, this driving force is transmitted to the swing arm 403 via the front side moving mechanism 410. At this time, since a portion of the belt 415 of the front side moving mechanism 410 wound around a pair of pulleys 414 moves in the width direction, the flag 417 fixed to this portion moves in the width direction together with the front side swing arm 403 and the alignment plate 401. Similarly, the rear flag 427 moves in the width direction together with the rear swing arm 404 and the alignment plate 402.

[0089] FIG. 10 shows a state in which the pair of alignment plates 401 and 402 are in the home position also in the width direction. In this state, the flags 417 and 427 have entered the jogger 1 HP detection sensor SN7 and the jogger 2 HP detection sensor SN8, respectively, and the sensors are in the ON state. The stacker control unit 330 determines in this state that the pair of alignment plates 401 and 402 are in the home position in the width direction. Then, when the pair of alignment plates 401 and 402 move outward in the width direction from the home position, the flags 417 and 427 come out of the jogger 1 HP detection sensor SN7 and the jogger 2 HP detection sensor SN8, respectively, and the sensors become OFF. The stacker control unit 330 controls the positions of the pair of alignment plates 401 and 402 in the width direction, for example, by counting the number of pulses of the jogger 1 moving motor MT20 and the jogger 2 moving motor MT21 when the jogger 1 HP detection sensor SN7 and the jogger 2 HP detection sensor SN8 are in the OFF state.

[0090] Next, a flag 277 is provided on a portion that is rotatably supported on the swing axis 405 of the paddle arm 276. Also, a paddle lift HP detection sensor SN9 is provided at a position where the flag 277 passes. When the paddle lift motor MT22 is rotationally driven to raise and lower the paddle 275, this driving force is transmitted to the paddle arm 276 via the paddle lift mechanism 440, and the flag 277 swings about the swing axis 405 together with the paddle arm 276. FIG. 10 shows a state where the paddle 275 is in the home position, that is, the retracted position. In this state, the flag 277 enters the paddle lift HP detection sensor SN9, and the sensor is in the ON state. The stacker control unit 330 determines in this state that the paddle 275 is in the home position.

[0091] Then, when the paddle 275 starts to descend from the retracted position, the flag 277 exits from the paddle lift HP detection sensor SN9, and the sensor becomes the OFF state. Further, with the sensor remaining in the OFF state, the paddle 275 descends and reaches the conveyance position shown in FIG. 11. The stacker control unit 330 determines that the paddle 275 is located at the conveyance position, for example, by driving the paddle lift motor MT22 for a predetermined number of pulses or a predetermined time after the flag 277 exits from the paddle lift HP detection sensor SN9.

[0092] [Interlocking mechanism] Next, the interlocking mechanism 460 that changes the angles of the pair of alignment plates 401 and 402 in conjunction with the swinging of the pair of swing arms 403 and 404 will be described with reference to FIGS. 12 and 13. The pair of alignment plates 401 and 402 are rotatably connected to the pair of swing arms 403 and 404 about a rotation axis 465, and extend upstream of the discharge direction from the rotation axis 465. In the present embodiment, the interlocking mechanism 460 rotates the pair of alignment plates 401 and 402 about the rotation axis 465 in conjunction with the swinging of the pair of swing arms 403 and 404 so that the angles of the alignment plates 401 and 402 with respect to the horizontal direction in the extending direction are substantially constant regardless of the positions in the swinging directions of the pair of swing arms 403 and 404.

[0093] FIGS. 19(a) and (b) described below show a state where a pair of alignment plates 401 and 402 are in the first position in the vertical direction and in the alignment position in the width direction. Here, as shown in FIG. 19(a), a line connecting the center P1 of the swing axis 405 and the center P2 of the rotation axis 465 is defined as the first virtual line α1, and a line connecting the center P2 of the rotation axis 465 and the upstream end of the pair of alignment plates 401 and 402 in the discharge direction, and the position P3 of the upper ends of the pair of alignment plates 401 and 402 in the alignment position is defined as the second virtual line α2. In this case, in the present embodiment, the angle θ formed by the first virtual line α1 and the second virtual line α2 is set such that the second position is smaller than the first position. Note that the first position is a position where the pair of alignment plates 401 and 402 can align the uppermost sheet in the vertical direction, and the second position is above the first position in the vertical direction and does not interfere with the sheet discharged from the discharge roller pair 42. The second position is the same as the home position shown in FIG. 6 in the vertical direction. Further, as shown in FIG. 19(a), in the present embodiment, the angle θ formed by the first virtual line α1 and the second virtual line α2 is an acute angle at the first position.

[0094] As described above, the swing arms 403 and 404 swing vertically about the swing axis 405 via the alignment plate lifting mechanism 430 by the jogger lifting motor MT19. The interlocking mechanism 460 changes the angle θ formed by the first virtual line α1 and the second virtual line α2 in conjunction with the swinging operation of the swing arms 403 and 404 about the swing axis 405. The interlocking mechanism 460 will be described in detail below. Note that the interlocking mechanism 460 is disposed inside the swing arms 403 and 404, respectively, and rotates the alignment plates 401 and 402 with respect to the tip portions of the swing arms 403 and 404 in conjunction with the swinging operations of the swing arms 403 and 404. Since the configurations of the interlocking mechanisms 460 for rotating the alignment plates 401 and 402 are the same, FIGS. 12 and 13 will representatively describe the interlocking mechanism 460 for rotating the alignment plate 402 in conjunction with the swinging operation of the swing arm 404.

[0095] The interlocking mechanism 460 includes a toothed pulley 461 as a first toothed pulley, a toothed pulley 462 as a second toothed pulley, and a toothed belt 463. The toothed pulley 461 is rotatably supported with respect to the swing shaft 405, and the phase in the rotational direction about the swing shaft 405 does not change regardless of the swinging operation of the swing arm 404. In the present embodiment, the toothed pulley 461 is fixed to the slide member 435. The toothed pulley 462 is fixed to the alignment plate 402 and is rotatable together with the alignment plate 402 about the rotation shaft 465. The toothed belt 463 is stretched between the toothed pulley 461 and the toothed pulley 462. The toothed pulleys 461 and 462 each have a plurality of teeth formed on their outer peripheral surfaces. The toothed belt 463 has a plurality of teeth formed on its inner peripheral surface that mesh with the plurality of teeth formed on the toothed pulleys 461 and 462, respectively.

[0096] Also, in the present embodiment, it has a spring 464 as a tension applying portion that applies tension to the toothed belt 463. The spring 464 connects the first portion 463a and the second portion 463b of the toothed belt 463 in a state where the portion between the first portion 463a and the second portion 463b is bent. That is, in a state where the toothed belt 463 between the first portion 463a and the second portion 463b is bent, one end portion of the spring 464 is fixed to the first portion 463a by the fixing portion 464a, and the other end portion of the spring 464 is fixed to the second portion 463b by the fixing portion 464b. Thereby, the pulling force of the spring 464 acts between the first portion 463a and the second portion 463b, and tension can be applied to the toothed belt 463.

[0097] Here, when no tension is applied to the toothed belt 463, there is a risk that the toothed belt 463 may be over-tensioned or slack due to the tolerances of the toothed pulleys 461 and 462 and the toothed belt 463. If the toothed belt 463 is over-tensioned, it will become a load for the swinging of the swing arm 404. On the other hand, if the toothed belt 463 is slack, the appropriate positioning of the rotation position around the rotation shaft 465 of the alignment plate 402 cannot be achieved. In other words, the alignment plate 402 cannot be placed in an appropriate posture. In particular, the posture of the alignment plate 402 is determined in a state where the lower portion of the toothed belt 463 stretched by the toothed pulleys 461 and 462 is in a stretched state. For this reason, when the lower portion of the toothed belt 463 bends, the upstream end of the alignment plate 402 will be in a posture where it has dropped relative to the desired posture. In order to apply tension to the toothed belt 463, for example, a tensioner that biases a part of the toothed belt 463 outward or inward may be provided. However, in this case, the device will become larger. Therefore, in the present embodiment, as described above, by bending a part of the toothed belt 463 and providing the spring 464, tension is applied to the toothed belt 463.

[0098] FIG. 12 shows a state where the alignment plate 402 is located at the home position (second position). When the jogging lifting motor MT19 is driven to lower the alignment plate 402 from this state, the swing arm 404 swings downward via the alignment plate lifting mechanism 430. At this time, the toothed pulley 461 fixed to the slide member 435 does not rotate, and the phase in the rotation direction is maintained. On the other hand, the toothed pulley 462 rotatably supported by the rotation shaft 465 provided at the tip of the swing arm 404 rotates via the toothed belt 463 spanned between the toothed pulley 461 and the toothed pulley 462 as the tip of the swing arm 404 drops and the vertical position with respect to the toothed pulley 461 changes.

[0099] As described above, since the toothed pulley 462 is fixed to the alignment plate 402, the alignment plate 402 also rotates about the rotation axis 465 together with the toothed pulley 462 due to the downward swing of the swing arm 404. That is, the position where the plurality of teeth on the inner peripheral surface of the toothed belt 463 mesh with the plurality of teeth on the outer peripheral surface of the toothed pulley 461 changes, and the toothed belt 463 rotates in the direction of arrow 463c in FIG. 12. As a result, the toothed pulley 462 rotates clockwise (in the direction of arrow 465a) when viewed in the direction of the rotation axis of the rotation axis 465 from the lower left to the upper right in FIG. 12. As a result, the alignment plate 402 descends to the first position shown in FIG. 13 while maintaining its posture, that is, the angle of the second virtual line α2 with respect to the horizontal direction substantially. When raising the alignment plate 402 from the first position to the second position, the toothed belt 463 and the toothed pulley 462 rotate in the reverse direction to the above, thereby substantially maintaining the posture of the alignment plate 402.

[0100] Note that although the number of teeth of the toothed pulleys 461 and 462 is the same, they may be different. Thereby, the ratio of the angle (the angle θ formed by the first virtual line α1 and the second virtual line α2) between the alignment plate 402 and the swing arm 404 with respect to the swing amount of the swing arm 404 can be changed. For example, when the number of teeth of the toothed pulley 462 is reduced with respect to the number of teeth of the toothed pulley 461, the variation amount of the angle θ with respect to the swing amount of the swing arm 404 increases, and when the number of teeth of the toothed pulley 462 is increased with respect to the number of teeth of the toothed pulley 461, the variation amount of the angle θ with respect to the swing amount of the swing arm 404 decreases.

[0101] In this embodiment, the alignment plate 402 is movable between the first position and the second position while the posture of the alignment plate 402 is substantially maintained by the interlocking mechanism 460 in this way. Therefore, although described in detail later, the angle θ formed by the first virtual line α1 and the second virtual line α2 is smaller at the second position shown in FIGS. 8, 10, and 12 than at the first position shown in FIGS. 9, 11, and 13. That is, in this embodiment, the pair of alignment plates 401 and 402 are movable between the first position and the second position while maintaining a posture extending upstream of the discharge direction from the rotation axis 465 with respect to the pair of swing arms 403 and 404.

[0102] For example, when a pair of alignment plates 401 and 402 are extended downstream of the discharge direction from the rotation axis 465, and the angles of the pair of alignment plates 401 and 402 with respect to the pair of swing arms 403 and 404 are the same at the first position and the second position, when the pair of alignment plates 401 and 402 are raised to the second position, the alignment plates 401 and 402 protrude above the swing arms 403 and 404. In this case, in order to ensure the space for the alignment plates 401 and 402 at the second position, a large space is required above the first tray 49. For this reason, the second tray 71 above the first tray 49 cannot be sufficiently lowered, and the loading amount of the sheets on the second tray 71 decreases.

[0103] On the other hand, in the present embodiment, the pair of alignment plates 401 and 402 are movable between the first position and the second position while generally maintaining a posture extended upstream of the discharge direction from the rotation axis 465 with respect to the pair of swing arms 403 and 404. For this reason, even when the alignment plates 401 and 402 move to the second position, the alignment plates 401 and 402 do not protrude into the space above the swing arms 403 and 404, or even if they protrude, the amount of protrusion is small. For this reason, it becomes easier to ensure the amount of descent of the second tray 71 above the first tray 49, and the loading amount of the sheets on the second tray 71 can be ensured.

[0104] In the above example, the interlocking mechanism 460 is constituted by a toothed pulley and a toothed belt, but these may be constituted by a plurality of gears. That is, the interlocking mechanism 460 may be configured to rotate the alignment plates 401 and 402 around the rotation axis 465 in conjunction with the swinging operation of the swing arms 403 and 404 so that the postures of the alignment plates 401 and 402 are maintained even when the swing arms 403 and 404 swing in the vertical direction. When the interlocking mechanism is constituted by a pulley and a belt without teeth, it is difficult to move the alignment plates 401 and 402 vertically while maintaining their postures due to the slippage of the pulley and the belt. For this reason, the interlocking mechanism 460 is preferably constituted by a toothed pulley and a belt as in the present embodiment, or by a plurality of gears that mesh with each other.

[0105] [Shift Discharge Mode] Here, a shift discharge mode will be described in which the sheet is moved (shifted) in the width direction and discharged onto the first tray 49 without performing a binding process to form a sheet bundle composed of a plurality of unbound sheets. In the shift discharge mode, for example, as shown in FIG. 30(b), a plurality of unbound sheet bundles are discharged onto the first tray 49 while being shifted from each other in the width direction. An example of such a shift discharge mode will be described with reference to FIGS. 14(a) to 22(b).

[0106] The stacker control unit 330 is capable of executing the shift discharge mode, and when the shift discharge mode is executed, the pair of alignment plates 401 and 402 operate as follows. First, a case will be described in which a job is executed to shift a first sheet bundle composed of a plurality of sheets stacked on the first tray 49 to one side in the width direction and stack a second sheet bundle on the first tray 49. In this case, after the pair of alignment plates 401 and 402 align the first sheet bundle stacked on the first tray 49 at the first position, they rise from the first position to the second position. Next, after the leading edge of the first sheet of the second sheet bundle following the first sheet bundle is discharged from the discharge roller pair 42, the pair of alignment plates 401 and 402 descend from the second position to the first position while being shifted to one side from the position where the first sheet bundle was aligned, and align the sheets included in the second sheet bundle.

[0107] The discharge operation of the first sheet S11 of the first sheet bundle will be sequentially described below. Here, a case will be described in which the first sheet bundle is shifted to the front side and stacked on the first tray 49, and then the next second sheet bundle is shifted to the rear side and stacked on the first sheet bundle. As shown in FIGS. 14(a) and 14(b), the sheet S11 conveyed through the straight path 28 passes through the first conveying roller 201, and the position of the edge (side edge) in the width direction of the sheet S11 is detected by the registration detection sensor SN2. At this time, the pair of alignment plates 401 and 402 are positioned at the sheet receiving position in the shift discharge mode from the home position shown in FIGS. 6 and 7. That is, the pair of alignment plates 401 and 402 move from the second position to the first position in the vertical direction, and in the width direction, they are positions separated by 5 mm from the width direction end (side edge) of the sheet at the position (reference position) where the sheet S11 is stacked on the first tray 49. In FIGS. 14(a) and 14(b), the alignment plates 401 and 402 are shifted to the front side with respect to the positions when discharging the sheet with the width direction center as a reference.

[0108] At this time, the pair of alignment plates 270 as shift members for aligning and shifting the sheets on the processing tray 37 also shift to the front side with respect to the position with the width direction center as a reference. That is, the pair of alignment plates 270 are positioned at the first width direction position when the pair of alignment plates 401 and 402 are positioned at the first receiving position where the sheets are received at a predetermined position of the first tray 49. Further, the pair of alignment plates 270 are positioned at the second width direction position shifted to one side (here, the front side) in the width direction from the first width direction position when the pair of alignment plates 401 and 402 are positioned at the second receiving position where the sheets are received at a position shifted to one side (here, the front side) in the width direction from a predetermined position of the first tray 49.

[0109] Here, the pair of alignment plates 270 has a guide surface as a guide portion on the shift member side for guiding a sheet that is conveyed toward the discharge roller pair 42 without being placed on the processing tray 37. The guide surfaces 270a are respectively formed on the upper surfaces of the pair of alignment plates 270 on the downstream side in the conveyance direction from the pre-processing roller 36, and guide the sheet that has passed through the pre-processing roller 36 to the discharge roller pair 42. Also, in the states of FIGS. 14(a) and (b), the paddle 275 remains in the home position.

[0110] Note that the front side is the lower side in FIG. 14(b), the rear side is the upper side in FIG. 14(b), and FIG. 14(a) is a cross-sectional view seen from the front side. The same applies to FIGS. 15(a) to 22(b). Also, discharging the sheet with reference to the center in the width direction means, for example, discharging the sheet in a state where the center in the width direction of the straight path 28 and the center in the width direction of the sheet substantially coincide, and discharging the sheet without shifting the sheet by the second conveyance roller 202 and the third conveyance roller 203.

[0111] Next, as shown in FIGS. 15(a) and (b), the stacker control unit 330 shifts the sheet S11 to the front side by the second conveyance roller 202 and the third conveyance roller 203 based on the detection result of the registration detection sensor SN2. Then, the sheet S11 shifted to the front side is delivered to the pre-processing roller 36 and further conveyed from the pre-processing roller 36 toward the discharge roller pair 42. At this time, the lower surface of the sheet S11 heading toward the discharge roller pair 42 is supported by the guide surfaces 270a formed on the upper surfaces of the pair of alignment plates 270 on the processing tray 37 shifted to the front side as described above. Then, the sheet S11 is discharged from the discharge roller pair 42 while being supported by the guide surfaces 270a. In this way, since the sheet S11 is discharged while being supported by the guide surfaces 270a, the sheet S11 is discharged from the discharge roller pair 42 in a state where it is given firmness by the guide surfaces 270a.

[0112] Next, as shown in FIGS. 16(a) and 16(b), when the rear end (the upstream end in the conveyance direction) of the sheet S11 passes through the discharge roller pair 42, the paddle 275 is lowered to the conveyance position, and the sheet S11 is conveyed upstream in the discharge direction while being dropped onto the first tray 49 by the paddle 275. That is, the paddle 275 scrapes in the sheet S11 and abuts the rear end of the sheet S11 against the abutting member 271. At this time, the second sheet S12 of the first sheet bundle has been conveyed to the pre-processing roller 36 in a state of being shifted to the front side, and the third sheet S13 has reached the first conveyance roller 201.

[0113] Next, as shown in FIGS. 17(a) and 17(b), the pair of alignment plates 401 and 402 align the sheet S11. At this time, since the sheet S11 is shifted to the front side, the front alignment plate 401 is moved 10 mm to the rear side without moving the rear alignment plate 402. In this state, the pair of alignment plates 401 and 402 are in the aligned positions. Here, since the receiving positions of the alignment plates 401 and 402 are positions separated by 5 mm from the positions of the widthwise ends of the sheet at the reference position (the position determined in control) at the time of shift discharge, the front alignment plate 401 is moved 10 mm to the rear side. Note that the positions of the widthwise ends of the sheet at the reference position differ depending on the size of the sheet.

[0114] Also, during the alignment of the sheet S11, the paddle 275 is raised to the retracted position. The timing of raising the paddle 275 is before the alignment plate 401 reaches the alignment position. In the present embodiment, the alignment plate 401 reaches the alignment position after the paddle 275 is separated from the upper surface of the sheet. The timing of starting the raising of the paddle 275 from the conveyance position and the timing of starting the movement of either or both of the alignment plates 401 and 402 from the receiving position to the alignment position are after a predetermined time has elapsed since the rear end of the sheet has passed through the sheet end detection sensor SN3.

[0115] During the alignment of the first sheet S11 by the pair of alignment plates 401 and 402, the second sheet S12 begins to be discharged from the discharge roller pair 42. At this time, the second sheet S12 may be discharged while being displaced in the width direction with respect to the sheet S11 being aligned. For example, in Fig. 17(b), the sheet S12 is discharged with a slight shift to the front side with respect to the sheet S11. Therefore, the sheet S12 discharged from the discharge roller pair 42 is guided above the alignment surface 4001 by the guide surface 4002 of the front alignment plate 401. In Fig. 17(a), the rear alignment plate 402 is shown, and it appears that the sheet S12 is placed on the rear alignment plate 402, but as shown in Fig. 17(b), the sheet S12 is not placed on the rear alignment plate 402. Also, with the second sheet S12 being discharged, the third sheet S13 is shifted to the front side by the second conveying roller 202 and the third conveying roller 203.

[0116] In the apparatus of this embodiment, the tolerance of the shift amount due to the tolerance of the shift amount by the second conveying roller 202 and the third conveying roller 203 is 5 mm. The front alignment plate 401 during alignment has moved 10 mm to the rear side from the receiving position of the sheet S1, and the alignment plate 401 at the receiving position is at a position 5 mm away from the widthwise end of the sheet at the reference position to the front side. Therefore, the position of the front alignment plate 401 at the alignment position is 5 mm shifted to the rear side from the widthwise end of the sheet at the reference position. Thus, when the sheet is shifted 5 mm to the front side, which is the maximum amount of the tolerance, from the widthwise end of the sheet at the reference position by the second conveying roller 202 and the third conveying roller 203 and the sheet is discharged from the discharge roller pair 42 in this state, this sheet may be discharged with a maximum shift of 10 mm to the front side with respect to the alignment surface 4001 of the front alignment plate 401.

[0117] Therefore, in this embodiment, the thickness of the guide surface 4002 in the width direction is set to 10 mm or more, for example, 11 mm. As a result, even if the second sheet S12 is displaced by 5 mm, which is the tolerance of the shift amount by the second conveying roller 202 and the third conveying roller 203, and is discharged from the discharge roller pair 42, the sheet S12 can be guided by the guide surface 4002.

[0118] Next, as shown in FIGS. 18(a) and 18(b), when the alignment operation of the sheet S11 is completed, the front alignment plate 401 is moved from the alignment position to the sheet receiving position. Specifically, the alignment plate 401 is moved 10 mm to the front side from the alignment position. At this time, the rear alignment plate 402 does not move. At this time, the second sheet S12 can fall onto the first sheet S11, being displaced from the guide surface 4002 of the front alignment plate 401. Then, when the rear end of the second sheet S12 passes through the discharge roller pair 42, the paddle 275 is lowered to the conveying position, and while dropping the sheet S12 with the paddle 275, it is scraped toward the abutting member 271. Further, similar to when aligning the first sheet S11, the front alignment plate 401 is moved to the alignment position to align the sheet S12.

[0119] The above operation is performed on the subsequent sheets included in the first sheet bundle, and as shown in FIGS. 19(a) and 19(b), the first sheet bundle is stacked on the first tray 49. Here, the first sheet S21 of the second sheet bundle is continuously conveyed following the first sheet bundle, but the second sheet bundle is stacked while being shifted rearward with respect to the first sheet bundle. For this reason, the positions in the width direction of the alignment plates 401 and 402 for aligning the second sheet bundle are different from the positions for aligning the first sheet bundle. Therefore, in this embodiment, before performing the discharge operation of the second sheet bundle, the pair of alignment plates 401 and 402 are raised. That is, the stacker control unit 330 raises the pair of alignment plates 401 and 402 from the first position to the second position by the jogging lift motor MT19 before discharging the next sheet from the discharge roller pair 42 with a shift to one side in the width direction (here, the rear side) with respect to the first sheet bundle composed of a plurality of sheets stacked on the first tray 49.

[0120] Since the distance between the last sheet of the first stack of sheets and the first sheet S21 of the second stack of sheets is the same as the distance between the plurality of sheets in the first stack of sheets, if the pair of alignment plates 401 and 402 are raised as described above before the discharging operation of the second stack of sheets, the discharging operation of the first sheet S21 will not be in time, and there is a risk that the sheet S21 will come into contact with the alignment plates 401 and 402. For this reason, in the present embodiment, as shown in FIGS. 19(a) and 19(b), the sheet S21 is temporarily made to wait in a buffer path 39 branched from between the second conveying roller 202 and the third conveying roller 203. And the timing of discharging the first sheet S21 of the second stack of sheets by the discharge roller pair 42 is delayed.

[0121] That is, when the stacker control unit 330 stacks the second stack of sheets including the first sheet S21 (the first sheet) and the second sheet S22 (the second sheet) on the first tray 49 by shifting the first stack of sheets loaded on the first tray 49 to one side in the width direction (here, the rear side), the sheet S21 is temporarily made to wait in the buffer path 39. Then, the third conveying roller 203 and the pre-processing roller 36 as the buffer conveying unit convey the sheet S22 together with the sheet S21 toward the discharge roller pair 42. Specifically, the sheet S21 waiting in the buffer path 39 is conveyed by the conveying roller 208 toward the straight path 28 and merged with the next sheet S22 being conveyed in the straight path 28. Then, the third conveying roller 203 and the pre-processing roller 36 convey the sheet S21 and the sheet S22 in a stacked state toward the discharge roller pair 42.

[0122] In this embodiment, the conveying roller 208 is also a shift roller capable of moving the sheet in the width direction. Therefore, with the first sheet S21 nipped between the third conveying roller 203 and the conveying roller 208, the sheet S21 can be shifted to the front side and the rear side. For this reason, while the third conveying roller 203 nips the sheets S21 and S22, with the sheet S21 nipped by the conveying roller 208 and the sheet S22 nipped by the second conveying roller 202, by moving the second conveying roller 202, the third conveying roller 203, and the conveying roller 203 in the same direction, it is possible to shift the sheets S21 and S22 in a state where they are overlapped. In FIGS. 19(a) and (b), the sheets S21 and S22 are shifted to the rear side in an overlapped state.

[0123] As shown in FIGS. 20(a) and (b), before the first and second sheets S21 and S22 of the second sheet bundle are discharged from the discharge roller pair 42, the pair of alignment plates 401 and 402 are raised to the second position. As described above, in this embodiment, the pair of alignment plates 401 and 402 are rotatably connected to the pair of swing arms 403 and 404 about the rotation axis 465 and extend upstream of the discharge direction from the rotation axis 465. And in such a configuration, the angle θ formed by the first virtual line α1 and the second virtual line α2 is made smaller at the second position shown in FIG. 20(a) than at the first position shown in FIG. 19(a). That is, when the swing arms 403 and 404 are swung upward to move the alignment plates 401 and 402 to the second position, the angles of the alignment plates 401 and 402 with respect to the swing arms 403 and 404 change so that the alignment plates 401 and 402 and the swing arms 403 and 404 are folded.

[0124] Here, when the angle θ formed by the first virtual line α1 and the second virtual line α2 is the same at the first position and the second position, if the swing amounts of the swing arms 403 and 404 are not increased, the alignment plates 401 and 402 will not move far enough away from the first position, so it will take a long time for the alignment plates 401 and 402 to reach the second position. In contrast, in the present embodiment, the angle θ formed by the first virtual line α1 and the second virtual line α2 is made smaller at the second position than at the first position. Therefore, even if the amount of upward swing of the swing arms 403 and 404 is small, the alignment plates 401 and 402 can be moved to a position far enough away from the first position. Accordingly, the swing amount of the swing arms 403 and 404 until the alignment plates 401 and 402 are moved from the first position to the second position can be reduced, and the time for raising the alignment plates 401 and 402 to the second position can be shortened.

[0125] Also, in the present embodiment, as described above, the angle θ formed by the first virtual line α1 and the second virtual line α2 at the first position is an acute angle. For this reason, the change amount of the angle θ when moving from the first position to the second position can be made small. That is, the swing amount of the swing arms 403 and 404 to the second position can be reduced. As a result, the time for raising the alignment plates 401 and 402 to the second position can be made even shorter. In order to make the angle θ an acute angle, it is preferable to make the lengths of the swing arms 403 and 404 sufficiently long, that is, to increase the distance between the swing shaft 405 and the rotation shaft 465. For this purpose, it is preferable to make the position of the swing shaft 405 with respect to the discharge direction as close as possible to the discharge roller pair 42. Thereby, even if the angle θ is small, it is possible to position the alignment plates 401 and 402 at the first position.

[0126] If the alignment plates 401 and 402 can be raised from the first position to the second position in a short time, by only temporarily waiting for the first sheet S21 of the second sheet bundle, the raising operation of the alignment plates 401 and 402 to the second position can be made in time before the discharging operation of this first sheet S21. That is, if the alignment plates 401 and 402 cannot be raised from the first position to the second position in a short time, for example, there is a possibility that the conveyance of the first sheet S21 of the second sheet bundle has to be stopped and the conveyance of the sheet S21 has to be started after waiting for the alignment plates 401 and 402 to rise to the second position. In this case, the productivity in the shift discharge mode will decrease. On the contrary, in the present embodiment, since the alignment plates 401 and 402 can be raised from the first position to the second position in a short time, the productivity can be improved.

[0127] Also, in the present embodiment, as shown in FIGS. 20(a) and (b), after raising the alignment plates 401 and 402 to the second position, the alignment plates 401 and 402 are moved to the rear side. That is, since the second sheet bundle is shifted to the rear side and discharged, the alignment plates 401 and 402 are moved to the rear side accordingly. If the alignment plates 401 and 402 are moved to the rear side at the first position, the stacking property of the already stacked first sheet bundle will be disturbed, so the alignment plates 401 and 402 are moved to the rear side after being raised to the second position. Note that even if the second position has not been reached, if the alignment plates 401 and 402 are separated from the topmost sheet of the already stacked first sheet bundle, the alignment plates 401 and 402 may be moved to the rear side during the raising.

[0128] Next, as shown in FIGS. 21(a) and (b), when the rear ends of the sheets S21 and S22 pass through the discharge roller pair 42, the paddle 275 is lowered to the conveyance position, and the sheets S21 and S22 are scraped toward the abutting member 271 while being dropped by the paddle 275. At this time, the third sheet S23 of the second sheet bundle is conveyed to the pre-processing roller 36 in a state of being shifted to the rear side.

[0129] Next, as shown in FIGS. 22(a) and (b), the pair of alignment plates 401 and 402 are used to align the sheets S21 and S22. At this time, since the sheets S21 and S22 are shifted toward the rear side, without moving the front alignment plate 401, the rear alignment plate 402 is moved 10 mm toward the front side. In this state, the pair of alignment plates 401 and 402 are in the aligned positions. Also, during the alignment of the sheets S21 and S22, the paddle 275 is raised to the retracted position.

[0130] During the alignment of the first and second sheets S21 and S22 by the pair of alignment plates 401 and 402, the third sheet S23 starts to be discharged from the discharge roller pair 42. Also in this case, similar to the case described with reference to FIGS. 17(a) and (b), when the sheet S23 is discharged with a slight shift toward the rear side with respect to the sheets S21 and S22, the sheet S23 is guided above the alignment surface 4001 by the guide surface 4002 of the rear alignment plate 402. When the alignment operation of the sheets S21 and S22 is completed, the rear alignment plate 402 is moved from the aligned position to the sheet receiving position, and further, the paddle 275 is lowered to the conveying position to scrape the third sheet S23 while dropping it toward the abutting member 271. Further, similar to the alignment of the sheets S21 and S22, the rear alignment plate 402 is moved to the aligned position to align the sheet S23. Such operations are performed until the last sheet of the second sheet bundle. During the discharge of the last sheet, the alignment plates 401 and 402 are returned to the receiving position. When the rear end of the last sheet passes through the discharge roller pair 42, the rear alignment plate 402 is moved toward the front side to align the last sheet, and the job is completed. At the end of the job, the pair of alignment plates 401 and 402 are returned to the home position. The positions of the alignment plates 401 and 402 at the end of the job will be described later.

[0131] [Straight Discharge Mode] Next, a straight discharge mode will be described in which the sheets are discharged onto the first tray 49 without shifting the sheets and without performing a binding process, thereby forming a stack of sheets consisting of a plurality of unbound sheets. In the straight discharge mode, for example, as shown in FIG. 30(a), a plurality of unbound stacks of sheets are discharged onto the first tray 49 without shifting. An example of such a straight discharge mode will be described with reference to FIGS. 23(a) to 27(b). Note that the basic operations of each part are the same as those in the above-described shift discharge mode, but differ from the shift discharge mode in that the sheets are discharged without shifting. However, even in the straight discharge mode, a shifting operation may be performed to align the center position in the width direction of the sheet with the center position in the width direction of the straight path 28.

[0132] The stacker control unit 330 is capable of executing the straight discharge mode, and when the straight discharge mode is executed, the pair of alignment plates 401, 402 are operated as follows. First, as shown in FIGS. 23(a) and (b), the sheet S1 conveyed to the straight path 28 passes through the first conveying roller 201, and the position of the edge (side edge) in the width direction of the sheet S1 is detected by the registration detection sensor SN2. At this time, the pair of alignment plates 401, 402 are positioned at the sheet receiving position in the straight discharge mode from the home position shown in FIGS. 6 and 7. That is, the pair of alignment plates 401, 402 move from the second position to the first position in the vertical direction, and in the width direction, they are positions separated by 5 mm from the width direction end (side edge) of the sheet at the position (reference position) where the sheet S1 is stacked on the first tray 49. In FIGS. 23(a) and (b), the alignment plates 401, 402 are in positions where the sheets are discharged based on the center in the width direction.

[0133] Next, as shown in FIGS. 24(a) and (b), based on the detection result of the registration detection sensor SN2, the stacker control unit 330 aligns the center position in the width direction of the sheet S1 and the center position in the width direction of the straight path 28 by the second conveyance roller 202 and the third conveyance roller 203. The center position in the width direction of the straight path 28 is the same as the center position in the width direction of the discharge roller pair 42 and the center position in the width direction of the first tray 49. Then, the sheet S1 is delivered to the pre-processing roller 36 and further conveyed from the pre-processing roller 36 toward the discharge roller pair 42. At this time, the lower surface of the sheet S1 heading toward the discharge roller pair 42 is supported by the guide surface 270a formed on the upper surfaces of the pair of alignment plates 270 on the processing tray 37. Then, the sheet S1 is discharged from the discharge roller pair 42 while being supported by the guide surface 270a.

[0134] Next, as shown in FIGS. 25(a) and (b), when the rear end (upstream end in the conveyance direction) of the sheet S1 passes through the discharge roller pair 42, the paddle 275 is lowered to the conveyance position, and the sheet S1 is dropped onto the first tray 49 by the paddle 275 and conveyed upstream with respect to the discharge direction. That is, the sheet S1 is scraped in by the paddle 275, and the rear end of the sheet S1 is abutted against the abutting member 271. At this time, the second sheet S2 has been conveyed to the pre-processing roller 36 with the center position in the width direction and the center position in the width direction of the straight path 28 aligned, and the third sheet S3 has reached the first conveyance roller 201.

[0135] Next, as shown in FIGS. 26(a) and (b), the alignment of the sheet S1 is performed by a pair of alignment plates 401 and 402. At this time, similar to the case described in the shift discharge mode, the paddle 275 is separated from the upper surface of the sheet S1 before the alignment plates 401 and 402 reach the alignment position. In the present embodiment, the alignment of the sheet S1 is performed by bringing the pair of alignment plates 401 and 402 into contact with both sides in the width direction of the sheet S1. During the alignment of the first sheet S1 by the pair of alignment plates 401 and 402, the second sheet S2 starts to be discharged from the pair of discharge rollers 42. At this time, due to the tolerance of the shift amount (5 mm) due to the tolerance of the shift amount by the second conveying roller 202 and the third conveying roller 203 described above, the second sheet S2 may be discharged while being displaced in the width direction with respect to the sheet S1 being aligned.

[0136] When the second sheet S2 is discharged while being displaced in the width direction, the leading end of the sheet S2 contacts the guide surface 4002 at any of the following timings. (1) While the alignment plates 401 and 402 are moving to the alignment position and the alignment surface 4001 is in contact with the side edge of the first sheet S1 to perform widthwise alignment. In the present embodiment, the time during this period is set to 50 ms. (2) After the alignment is completed and the alignment plates 401 and 402 are moving from the alignment position toward the receiving position. In the present embodiment, the time during this period is set to 30 ms.

[0137] And in any case, the sheet S2 is guided above the alignment surface 4001 by any of the guide surfaces 4002 of the alignment plates 401 and 402. That is, when the sheet S2 is displaced to the front side, it is guided by the guide surface 4002 of the front alignment plate 401, and when the sheet S2 is displaced to the rear side, it is guided by the guide surface 4002 of the rear alignment plate 402.

[0138] That is, the guide surface 4002 allows the leading edge of the next sheet to be received when the alignment plates 401 and 402 are in the aligned position or during the movement from the aligned position to the receiving position. In other words, when the alignment plates 401 and 402 are in either of the positions (1) and (2) described above and the leading edge of the next sheet reaches the downstream side of the upstream end of the alignment surface 4001 of the alignment plates 401 and 402 in the discharge direction (the direction along the nip line N2), the next sheet is guided by the guide surface 4002.

[0139] Also, before the alignment plates 401 and 402 move from the receiving position to the aligned position when aligning the first sheet, the leading edge of the next sheet does not reach the upstream end of the alignment surface 4001 of the alignment plates 401 and 402. This is because if the leading edge of the next sheet reaches the alignment surface area β (Fig. 26(a)) before the alignment plates 401 and 402 reach the aligned position, the next sheet will be nipped by the discharge roller pair 42 and then hit against the alignment surface 4001, which may damage the sheet.

[0140] Next, as shown in Figs. 27(a) and (b), after the alignment operation of the sheet S1 is completed, the alignment plates 401 and 402 are moved from the aligned position to the sheet receiving position. Then, when the trailing edge of the second sheet S2 passes through the discharge roller pair 42, the paddle 275 is lowered to the conveying position, and the sheet S2 is scraped toward the abutting member 271 while being dropped by the paddle 275. Further, similar to the alignment of the first sheet S1, the alignment plates 401 and 402 are moved to the aligned position to align the sheet S2. At this time, the third sheet S3 is conveyed to the pre-processing roller 36.

[0141] For the sheet S3 as well, it is guided by the guiding surface 4002 of either the alignment plates 401 or 402, and similar to the sheet S2, the alignment in the width direction is performed by the alignment plates 401 and 402. Such an operation is carried out until the last sheet of the sheet bundle. During the discharge of the last sheet, the alignment plates 401 and 402 are returned to the receiving position. When the rear end of the last sheet has passed through the discharge roller pair 42, the alignment plates 401 and 402 are moved to the alignment position to align the last sheet, and the job is terminated. At the end of the job, the pair of alignment plates 401 and 402 are returned to the home position. The positions of the alignment plates 401 and 402 at the end of the job will be described later.

[0142] As described above, in this embodiment, in either the shift discharge mode or the straight discharge mode, even when discharging a plurality of consecutive sheets with a reduced interval to the first tray 49, the sheets can be aligned by the alignment plates 401 and 402. Therefore, the productivity of the apparatus can be improved.

[0143] In the straight discharge mode of this embodiment, the aspect of moving both the alignment plates 401 and 402 from the receiving position to the alignment position during sheet alignment has been shown. However, for example, during sheet alignment, the alignment plate 401 can be fixed at a position where the sheet will not hit even if it is displaced to the alignment plate 401 side and discharged, and only the alignment plate 402 is moved from the receiving position to the alignment plate 401 side to align the discharged sheet by butting it against the alignment plate 401, and then the alignment plate 402 is moved to the receiving position. In that case, since the alignment plate 402 may be hit by the next sheet during the alignment operation, the guiding surface 4002 may be provided only on the alignment plate 402.

[0144] [Position of the alignment plate at the end of the job] Next, with reference to FIGS. 28 to 29(b), the positions of the alignment plates 401 and 402 at the end of the job will be described. When the job of loading sheets on the first tray 49 including each mode as described above is completed, the alignment plates 401 and 402 are positioned at the home position. Here, when the home positions of the alignment plates 401 and 402 are positions farther outward than the alignment position in the width direction, for example, positions farther outward than the sheet receiving position, the alignment plates 401 and 402 may interfere when the operator takes out the sheet or the stack of sheets on the first tray 49.

[0145] Therefore, in the present embodiment, one of the pair of alignment plates 401 and 402 (for example, the front alignment plate 401) moves to the other side in the width direction (for example, the rear side) from one end in the width direction (for example, the front end) of the sheet S loaded on the first tray 49 after the job of loading sheets on the first tray 49 is completed and it has risen from the first position to the second position. Also, in the present embodiment, the other alignment plate of the pair of alignment plates 401 and 402 (for example, the rear alignment plate 402) also moves to one side in the width direction (for example, the front side) from the other end in the width direction (for example, the rear end) of the sheet S loaded on the first tray 49 after the job is completed and it has risen from the first position to the second position. That is, as shown in FIGS. 28 and 29(a), both of the pair of alignment plates 401 and 402 are raised from the first position to the second position at the end of the job and are positioned inside both ends in the width direction of the sheet S loaded on the first tray 49. In the present embodiment, this state is set as the home position of the pair of alignment plates 401 and 402.

[0146] Note that the positions of the alignment plates 401 and 402 in the width direction at their home positions are preferably inside the both ends in the width direction of the sheet with the minimum size processable by the apparatus. However, considering the frequency of use, the positions of the alignment plates 401 and 402 in the width direction at their home positions may be set inside the both ends in the width direction of a sheet (e.g., A4 size) larger than the sheet with the minimum size. Also, regardless of the size of the sheet loaded on the first tray 49, it is preferable that the positions of the alignment plates 401 and 402 in the width direction at their home positions be at predetermined positions. At this time, the reference loading position of the sheet is the case where the sheet is discharged with the center in the width direction as a reference.

[0147] Also, considering the case where the sheet is discharged in the shift discharge mode, the positions of the alignment plates 401 and 402 in the width direction at their home positions may be set inside the both ends in the width direction of the sheet regardless of the direction in which the sheet shifts. That is, when the sheet shifts to the front side and is loaded on the first tray 49, the position of the rear alignment plate 402 is set inside the rear end of the sheet, and when the sheet shifts to the rear side and is loaded on the first tray 49, the position of the front alignment plate 401 is set inside the front end of the sheet. In any case, the pair of alignment plates 401 and 402 are positioned inside the both ends in the width direction of the sheet.

[0148] By defining the positions of the alignment plates 401 and 402 in the width direction at their home positions in this way, when the operator takes out the sheet or the stack of sheets loaded on the first tray 49, the alignment plates 401 and 402 are less likely to get in the way, and the removability of the sheet or the stack of sheets from the first tray 49 can be improved. In particular, since the alignment plates 401 and 402 on both sides are positioned inside the both ends in the width direction of the sheet, when the number of sheets in the stack of sheets is large, it is easy to grasp and take out the sheets from the front side and the rear side with both hands.

[0149] Note that, as shown in FIG. 29(b), at least only the front alignment plate 401 may be moved to the rear side in the width direction from the front end of the sheet stacked on the first tray 49 after the job is completed and the sheet is lifted from the first position to the second position. In this case, the widthwise position of the rear alignment plate 402 may be a position separated outward from the alignment position in the width direction, for example, a position further outward than the sheet receiving position. Since the operator often takes out the sheet or the stack of sheets on the first tray 49 from the front side, even by simply positioning the front alignment plate 401 inward from the widthwise end of the sheet, the removability of the sheet or the stack of sheets from the first tray 49 can be improved.

[0150] Also, even during the standby of the job, the widthwise positions of the alignment plates 401 and 402 may be set to the positions at the end of the job as described above. That is, it is preferable to position the alignment plates 401 and 402 at the home position even during the standby of the job. During the standby of the job, the power of the apparatus is ON, but it is a standby state in which the job is not being executed. Also, during the standby of the job, a sleep state with less power consumption than the standby state may be included.

[0151] [Another Example of Alignment Plate] The pair of alignment plates 401 and 402 described above are connected via swing arms 403 and 404 and a rotation shaft 465 at the ends in the longitudinal direction of the alignment plates 401 and 402 (the direction extending upstream from the rotation shaft 465 in the discharge direction). However, the position where the alignment plate is connected to the swing arm is not limited to the end in the longitudinal direction. For example, as shown in FIG. 31, it may be connected via a swing arm 404A (403A) and a rotation shaft 465 at an intermediate portion in the longitudinal direction of the alignment plate 402A (401A). FIG. 31 shows the rear alignment plate 402A and the swing arm 404A, but the same applies to the front alignment plate 401A and the swing arm 403.

[0152] Regarding the alignment plate 402A(401A) shown in FIG. 31, it is also rotatably connected to the swing arm 404A(403A) about the rotation axis 465, and extends upstream and downstream of the discharge direction with respect to the rotation axis 465. Further, like the alignment plates 401 and 402, the alignment plate 402A(401A) includes a guide surface 4012 as a guide portion and a sheet receiving surface 4013 as an upstream guide portion, and can guide the next sheet above the alignment surface 4011 that aligns the sheet even when the next sheet is discharged during the alignment of the sheet.

[0153] <Other Embodiments> In the above-described embodiment, the configuration in which the binding process is performed as a predetermined process performed by the processing unit has been described. However, the predetermined process is not limited to the binding process, and may be a folding process, a shift process, a punching process, a crease (creasing), a lamination process, or the like. Further, in the above-described embodiment, the example in which the control around the first tray 49 of the sheet processing apparatus B is performed by the stacker control unit 330 (CPU 331) has been described. However, this control may be performed by the control unit 310 (CPU 311) of the image forming apparatus A.

[0154] Further, the disclosure of the present embodiment includes the following configurations. (Configuration 1) A discharge unit that discharges the sheet in the discharge direction, A stacking tray that stacks the sheets discharged by the discharge unit, A lifting unit that raises and lowers the stacking tray, A pair of alignment members that are located on both sides in the width direction of the sheet that intersects the discharge direction with respect to the uppermost sheet stacked on the stacking tray, and perform alignment in the width direction of the uppermost sheet, An alignment member moving unit that moves the pair of alignment members between an alignment position for aligning the uppermost sheet in the width direction and a position separated from the uppermost sheet in the width direction from the alignment position, An alignment member lifting unit that can lift and lower the pair of alignment members between a first position where the uppermost sheet can be aligned and a second position that is above the first position and does not interfere with the sheet discharged from the discharge unit, One of the pair of alignment members moves to the other side in the width direction of the sheet loaded on the loading tray after the job of loading the sheet on the loading tray is completed and the member has risen from the first position to the second position. (Configuration 2) The other of the pair of alignment members is the sheet loading device according to Configuration 1, which moves to the one side in the width direction after the job is completed and the member has risen from the first position to the second position, relative to the other end in the width direction of the sheet loaded on the loading tray. (Configuration 3) One of the pair of alignment members is the sheet loading device according to Configuration 1 or 2, which is located on the other side in the width direction relative to the one end in the width direction of the sheet loaded on the loading tray at the second position during standby of the job. (Configuration 4) The alignment member moving unit includes a first moving unit that moves the one alignment member in the width direction and a second moving unit that moves the other alignment member in the width direction, and the pair of alignment members can be independently moved in the width direction, which is the sheet loading device according to any one of Configurations 1 to 3. (Configuration 5) A processing unit that performs a predetermined process on the sheet; The sheet loading device according to any one of Configurations 1 to 4, and the sheet processing device includes the sheet loading device. The sheet loading device is a sheet processing device that loads a sheet on which the predetermined process has been performed by the processing unit or a sheet on which the predetermined process has not been performed. (Configuration 6) An image forming apparatus having an image forming unit that forms an image on a sheet; The sheet processing device according to Configuration 5, and the image forming system includes the sheet processing device. The sheet processing device is an image forming system that performs the predetermined process on the sheet on which an image has been formed by the image forming unit. (Configuration 7) In the image forming system according to Configuration 6, the one side in the width direction is the side where the operator operates the image forming apparatus.

Explanation of Signs

[0155] 3 ··· Image forming unit 36 ··· Pre - processing roller (buffer conveying unit, conveying unit) 37 ··· Processing tray (placement unit) 39 ··· Buffer path (buffer unit) 42 ··· Discharge roller pair (discharge unit) 47 ··· Binding processing mechanism (processing unit) 49 ··· First tray (loading tray) 49a ··· Loading surface 203 ··· Third conveying roller (buffer conveying unit) 270 ··· Alignment plate (shift member) 330 ··· Stacker control unit (control unit) 401, 402, 401A, 402A ··· Alignment plates (alignment members) 403, 404, 403A, 404A ··· Swing arms 405 ··· Swing axis 430 ··· Alignment plate lifting mechanism (drive transmission unit) 432 ··· Parallel axis 433 ··· Connecting part 434 ··· Engagement hole (engagement part) 460 ··· Interlocking mechanism 461 ··· Toothed pulley (first toothed pulley) 462 ··· Toothed pulley (second toothed pulley) 463 ··· Toothed belt 464 ··· Spring (tension applying part) 465 ··· Rotating axis 4001, 4011 ··· Alignment surface 4002, 4012 ··· Guide surface (guide part) 4003, 4013 ··· Sheet receiving surface (upstream guide part) 1000 ··· Image forming system A ··· Image forming device A1 ··· Image forming unit B ··· Sheet processing device B1 ··· Processing unit MT18 ··· Tray lifting motor (lifting part) MT19 ··· Jogger lifting motor (integrating member lifting section) MT20 ··· Jogger 1 movement motor (integrating member movement section, first movement section) MT21 ··· Jogger 2 movement motor (integrating member movement section, second movement section)

Claims

1. A discharge unit that discharges a sheet in the discharge direction; A stacking tray that stacks the sheets discharged by the discharge unit; A lifting unit that raises and lowers the stacking tray; A pair of alignment members that are located on both sides in the width direction of the sheet intersecting the discharge direction with respect to the uppermost sheet stacked on the stacking tray, and perform alignment in the width direction of the uppermost sheet; An alignment member moving unit that moves the pair of alignment members to an alignment position for aligning the uppermost sheet in the width direction and a position away from the uppermost sheet in the width direction from the alignment position; An alignment member lifting unit that can lift and lower the pair of alignment members between a first position where the uppermost sheet can be aligned and a second position that is above the first position and does not interfere with the sheet discharged from the discharge unit; A sheet stacking device, wherein one of the pair of alignment members moves to the other side in the width direction from one end in the width direction of the sheet stacked on the stacking tray after the job of stacking the sheet on the stacking tray is completed and the alignment member has risen from the first position to the second position.

2. The sheet stacking device according to claim 1, wherein the other alignment member of the pair of alignment members moves to the one side in the width direction from the other end in the width direction of the sheet stacked on the stacking tray after the job is completed and the alignment member has risen from the first position to the second position.

3. The sheet stacking device according to claim 1, wherein one of the pair of alignment members is located on the other side in the width direction from one end in the width direction of the sheet stacked on the stacking tray at the second position during standby of the job.

4. The alignment member moving unit includes a first moving unit that moves one of the alignment members in the width direction and a second moving unit that moves the other alignment member in the width direction, and the pair of alignment members can be independently moved in the width direction. The sheet stacking device according to claim 1.

5. A processing unit that performs a predetermined process on the sheet, and the sheet loading device according to any one of claims 1 to 4, wherein the sheet loading device is a sheet processing device that loads a sheet on which the predetermined process has been performed by the processing unit or a sheet on which the predetermined process has not been performed.

6. An image forming apparatus having an image forming unit that forms an image on a sheet, and the sheet processing device according to claim 5, wherein the sheet processing device is an image forming system that performs the predetermined process on the sheet on which the image has been formed by the image forming unit.

7. The image forming system according to claim 6, wherein the one in the width direction is the side where the operator operates the image forming apparatus.

Images