JP3119393B2 - Sheet post-processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus, more specifically, for example, an image forming apparatus such as a copying machine or a printing machine.
The present invention relates to a sheet post-processing apparatus including a sorting apparatus that sequentially sorts and stores sheets such as copy sheets discharged after image formation into one or more trays (hereinafter, referred to as “bin trays”) and a stack apparatus that stacks a sheet bundle. Things.

[0002]

2. Description of the Related Art Conventionally, a sheet post-processing apparatus for sorting and storing sheets exceeding the number of bin trays has been devised. This apparatus has one or more bin trays and sorts sheets. A stacking device provided with the sorting device and a stack device provided with a stack tray for loading a sheet bundle sequentially transferred from the bin tray; For example, FIG. 33 is a top view of a conventional apparatus (not known), and shows a sorting apparatus 600 which is located downstream of the image forming apparatus 500 and in which one or more bin trays 601 are vertically stacked. A stacking device 700 is provided in front of the sorting device 600, and the sheet bundle distributed to the bin tray 601 is sequentially stacked.
00 is stored in a stack tray 701. In addition, as a means for transferring the sheet bundle, cost reduction,
From the viewpoint of simplification of the configuration, a roller pair transport is suitable. FIG. 34 is a main cross section of FIG.
The sheet bundle is held between the bin tray 601 and the stack tray 701 by nipping and rotating the sheet bundle in the same direction. As another prior art, there is a sheet post-processing apparatus described in JP-A-2-249861. The sheet post-processing apparatus described in this publication has a configuration in which a staple tray for stapling is arranged below a bin tray, and a stack tray for stacking a stapled sheet bundle is arranged below the staple tray. .

[0003]

However, when a sheet bundle is conveyed by a pair of rollers as in the above-mentioned conventional example, a bundle shift occurs due to the following factors.

As shown in FIG. 35, a pair of rollers 702, 70
3 is pressed against the sheet bundle with a holding force f required to convey the sheet bundle S. At this time, since the sheet is an elastic body, a bending w shown in the drawing occurs. The radius of curvature r of the deflection w is in the roller contact sheet is r ₀ (the radius of the roller and r _0), increases as toward the center. Therefore, the transport amount of the sheet due to the predetermined angle rotation by the roller pair is larger in the center sheet, and as a result, FIG.
As shown in (2), there is a possibility that the bundle may be placed on the stack tray 701 in a state in which the bundle protrudes from the center.

Further, the above conventional example has the following problem. (1) As shown in FIG. 42, the sheet bundle SA already stacked on the stack tray TR comes into contact with the leading end of the sheet bundle SB to be stacked next, so that the top sheet Pa of the already stacked sheet bundle SA is moved in the transport direction. Taken to. For this reason, a shift preventing member or the like for pressing the already-stacked sheet bundle SA is required, and the configuration may be complicated. (2) When the sheet bundle to be transferred from the bin tray to the stack tray TR has been stapled in the sorting device, as shown in FIG. 43, the staple HR of the already stacked sheet bundle SA is conveyed next. When the leading end of the incoming sheet bundle SB comes into contact with the sheet bundle SB, there is a possibility that the leading end of the sheet bundle SB may be bent, or an obstacle such as a positional deviation of the already stacked sheets SA may occur. (3) When a sheet bundle consisting of a small number of sheets (about 2 to 5 sheets) is stapled by the stapler ST and stored in the multi-stack tray TR, the sheet bundle is stapled as shown in FIG. Since the end portion is stacked higher by the binding staple TR than the tip end portion where the staple is not bound, a loop portion R is generated as the loading progresses. Since the stacked lower sheet bundle has a small loop amount, the rear end thereof can be brought into contact with the reference wall W to maintain the alignment state, but the upper sheet bundle has a large loop amount and finally falls down the loop portion. Then, the consistency is deteriorated. In order to always keep the paper surface stored in the stack tray horizontal in order to prevent this drop displacement, it is necessary to control the angle of the stack tray as needed, and the structure may be complicated. (4) In the sheet post-processing apparatus disclosed in JP-A-2-249861, there is a problem that the height of the apparatus is increased because all the bins, staple trays, and stack trays are arranged vertically. In addition, since the stack tray is disposed at the lowermost position, the user is required to lean out the sheet bundle and take out the sheet bundle, resulting in a problem that the operability is poor.

[0006]

SUMMARY OF THE INVENTION According to the present invention, an object of the present invention is to solve the problems of the above-mentioned conventional apparatus, and to provide a sheet post-processing which is excellent in operability in which a sheet bundle can be easily taken out. Providing a sheet post-processing apparatus capable of maintaining an alignment state of a sheet bundle on a stack tray;
Is what makes it possible.

[0007] In order to achieve the above object, the present invention provides:
A plurality of sheet trays capable of classifying and storing sheets, sheet discharging means for discharging the sheets to the sheet tray,
In a sheet post-processing apparatus comprising: a sheet stacking unit that takes out and stacks a sheet on the sheet tray, wherein the sheet stacking unit conveys a sheet on the sheet tray; A first sheet stacking tray for stacking sheets, second sheet conveying means for conveying the sheets on the first sheet stacking tray, and a second sheet stacking tray for receiving and stacking the conveyed sheets; A first sheet stacking tray provided at a position substantially orthogonal to a sheet advancing direction on the sheet tray with respect to the sheet tray;
The second sheet stacking tray is provided at a position substantially orthogonal to the sheet advancing direction on the first sheet stacking tray with respect to the first sheet stacking tray. This makes it possible to arrange the so-called stack tray at a position that is easy for the user to handle, thereby improving operability.

In addition, a sheet bundle on a stack tray is aligned by providing an alignment reference plate which is in contact with a leading end of a sheet discharged to the second sheet stacking plate by the second sheet conveying means. It is possible to do. Also, by locking the leading end of the sheets already stored on the stack tray with the reference plate, the loaded stack is brought into alignment with the next sheet bundle to be conveyed to the stack tray. Can hold.

Further, the second sheet conveying means is constituted by a pair of rollers configured to advance the lower side of the sheet bundle when conveying a plurality of sheet bundles, so that the lower part of the sheet bundle is first. Since the upper sheets are sequentially brought into contact with the reference plate and moved to the reference plate by inertial force, the positioning and alignment of all sheets can be performed more effectively.

The sheet bundle whose rear end is bound by the binding means or the like on the bin tray has the unbound front end facing the stapled rear end, and the second sheet bundle starts at the second end.
The sheet is conveyed by the sheet conveying means and is brought into contact with and aligned with the reference plate, so that the stackability on the stack tray is improved.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an overall view of a sheet post-processing apparatus embodying the present invention. The sorting apparatus 100 having at least one bin tray B is provided downstream of the image forming apparatus 300, and a stacker apparatus 200 for stacking and stacking a bundle of sheets is provided on the front side of the sorting apparatus 100.

FIG. 2 is a cross-sectional view showing a specific configuration of the image forming apparatus 300. As shown in FIG. 2, the image forming apparatus 300 includes a copier 310 (a sheet feeding deck 311 and a photosensitive member 31).
2, a fixing device 313, an image reading device 314, a platen glass 315, etc.), an automatic document feeder 320 disposed above the copying machine 310, and a copying machine 310.
And a folding device 330 arranged on the downstream side.

The document P ₁ placed on the document table 321 of the automatic document feeder 320 is separated one by one by the separating means 322 in order from the bottom, and the path P 323 is placed on the platen glass 315 of the copying machine 310. Fed through
After being read by the optical system of the copying machine 310 a predetermined number of times, the document is discharged to the uppermost surface of the document table 321 through the path 324. Note that a partition lever is interposed between the copied original and the uncopied original so that the original can be classified.

FIG. 3 is a main cross section of the sorting apparatus 100.
In this sorting device 200, the sorting device 200 has vertically stacked one or more bin trays B, and the bin trays B are provided with pins 2, 2 attached to both sides of the bin trays B around the lifting / lowering rotating bodies 3, 3. It engages with the engraved groove, and is raised or lowered one by one by one rotation of the elevating rotating bodies 3 and 3 (driving of the motor 9).

After the sheet copied by the image forming apparatus 300 is inserted into the guide entrance 1 of the sorting apparatus 100,
The flapper 4 switches paths between non-sorting and sorting. Flapper 4 for non-sort
Is positioned at the broken line, and the sheet passes through the non-sort path 5 and is stored in the non-sort tray 9 by the discharge roller 8.
On the other hand, at the time of sorting, the flapper 4 is at the solid line position, and sheets are stored one by one in each bin tray B by the discharge rollers 7 through the sort path 6.

Reference numeral 400 denotes a staple unit for stapling the sheet bundle stored in the bin tray B, and a stacking device 200 (to be described later) for collectively storing the sheet bundle is provided at the dashed line on the front side of the sorting device 100. Have been.

Next, a description will be given of a bin unit 10 that includes bin trays B and an alignment unit (which will be described later in detail) that aligns the sheets stored in the bin tray.

As shown in detail in FIG. 4, the bin unit 10 is provided with an alignment reference member 13 for contacting the sheet S from the bin cover 11 to the bottom of the bin frame 12.

At the base end of the bin frame 12, a support plate 14 is fixedly mounted. On the support plate 14, the upper end is fixed to the upper arm 15a and the lower end is fixed to the lower arm 15b. The rotation center shaft 16 is rotatably supported by a rotation shaft (not shown) provided on the support plate 14 and a rotation shaft 17 provided on the bin cover 11.

On the support plate 14, a sector gear 18 is disposed rotatably about a rotation shaft provided on the support plate 14. The sector gear 18 has the lower arm 15b.
Has been fixed.

Further, a pulse motor 19 is disposed below the support plate 14, and a gear 19 a fixed to an output shaft of the pulse motor 19 meshes with the sector gear 18.

At the tip of the lower arm 15b and the tip of the upper arm 15a, there is provided an alignment rod 21 which penetrates the notch 20 provided in each bin B through all the bins. The alignment rod 21 is configured to swing by rotation of the sector gear 18.

Further, a light-shielding plate 22 is provided on the lower arm 15b, and the light-shielding plate 22 rotates integrally with the lower arm 15b, so that a home position sensor 23 disposed on the back side of the bin frame 12 is provided. Are turned on and off.

The reference rod 13 is located in front of the alignment rod 21.
Are arranged so as to penetrate through notches 24 provided in all the bins similarly to the alignment rod 21, and are attached to the support plate 14 fixed to the base end of the bin frame 12.

A pulse motor 25 is disposed on the support plate 14, and a gear 26 fixed to an output shaft of the pulse motor 25 meshes with a sector gear 27, and the reference bar 13 is attached to the sector gear 27. The reference rod 13 swings around a fulcrum 28 as the pulse motor 25 rotates. The fulcrum 28 is the upper arm 13a of the reference rod 13.
Of the bin cover 11 and a concave portion provided at a predetermined position of the bin cover 11.

As shown in FIG. 5, which is a top view of FIG. 3, when the copying operation of the image forming apparatus 300 is started, the reference rod 13 stopped at the standby position a (the position indicated by the broken line) becomes the pulse motor 25. the rotary moved in the arrow X ₁ direction, and stops at the alignment reference position (the position of the hands).

Thereafter, the sheet S on which an image has been formed by the image forming apparatus 300 is discharged from the paper discharge rollers 7 and 7 to the bin tray B, and the bin tray B, which is disposed with the rear end stopper B 'inclined downward, has its own weight at the rear end. Move toward stopper B '.

[0029] Then, as shown in FIG. 6, the aligning rod 21 arrow X ₂ from the standby position b (broken line position) by a pulse motor 19 which rotates on the basis of a pulse signal corresponding to the sheet size
The sheet is moved in the direction by a predetermined amount (the position indicated by the solid line) and the sheet is pressed against the reference rod 13 stopped at the alignment reference position.

The reference rod 13 continues to stop at the alignment reference position until all the sheets are stored in the bin trays B by the image forming apparatus 300, but after the alignment rod 21 moves by a predetermined amount, the next sheet is discharged. Returns to the standby position b in preparation for. The above operation is repeated, and a sheet bundle including one or more sheets S is placed on one bin tray
Then, the rear end abuts on the rear end stopper B 'of the bin tray B and is aligned. It should be noted that the sheets S stored in the other bin trays B are similarly aligned by passing through all the bin trays B.

A staple unit 400 incorporated in the sorting apparatus 100 performs a staple binding operation on a sheet bundle stacked on a bin tray B supported by the elevating rotary unit 3.

As shown in FIG. 7, the staple unit 400 has two identical electric staplers ST.
The electric stapler ST is fixed to the first tray 401. The first tray 401 is engaged with a second tray 402 located therebelow by a guide member (not shown), a rack gear 401a engraved on a side of the first tray 401, and a motor 403 fixed to the second tray. Pinion gear 40
In engagement between 4, and is reciprocally moved in the Y ₁ direction.
The second tray 402 has a slit 402a formed by a guide rail 4 provided on a sorter body frame (not shown).
Built in 05, the rack gear 402b provided in the second tray 402 has a smoothly reciprocally moved in the arrow Y ₂ direction by the motor 407 to the pinion gear 406 is mounted which meshes with the rack gear 402b. The electric stapler ST used here may be, for example, the one described in Japanese Patent Application Laid-Open No. 1-146674, and the detailed description is omitted here, but the lower jaw ST ₁ and the upper jaw ST ₂ are provided with sheets. by interposing a wood, it is to stapling in clinching operation of the lower jaw ST ₁ and the upper jaw ST _2.

Next, the configuration of the stack device 200 will be described. As shown in FIG. 5 which is a top view and FIG. 8 which is a front view thereof, an intermediate tray 201 and a stack tray 202 are installed in the stacking device 200. Intermediate tray 20
1 is an inclined surface 201a having a rear end parallel to the bin tray B of the sorting apparatus 100 and a rear end stopper 201b.
The tip is formed by a horizontal surface 201c, and the front and rear side plates 203 of the stacking device 200,
204.

The stack tray 202 is the intermediate tray 2
01 with respect to the base 20
5 horizontally mounted. Two pins 207, 208 project from the left side of the base 205, and the pins 207, 208 are fitted into holes (not shown) cut in the vertical direction of the left side plate 206. And FIG. 8 and its L
As shown in FIG. 9, which is a −L cross section, pulleys 209 and 210 are disposed vertically on the left side plate 206, and a belt 211 is hung between the pulleys. Further, the belt 211
Is fixed to the pin 208, and the base 205
The stack tray 202 can be moved up and down by driving a motor 212 directly connected to the lower pulley 210.

In the vicinity of the leading end 201c of the intermediate tray 201, the sheet bundle on the bin tray B is transferred to the intermediate tray 201.
The gripper device 220 for transferring to the front and rear side plates 203,
It is supported by rails 221 and 222 attached across 204. Further, pulleys 223 and 224 are provided on the front and rear side plates 203 and 204, and a belt 225 is stretched around the pulleys. A part of the belt 225 is fixed to the gripper device 220 and the pulley 2
When the motor 23 rotates by a motor (not shown), the gripper device 2
20 is guided by rails 221 and 222 and reciprocates in the Z direction (see FIG. 5).

Next, the gripper device 220 will be described with reference to FIG. Three shafts 227, 228, 229 are supported on the side plates 226, 226. An upper gripper 241 and a lower gripper 242 are disposed on the shaft 229, and the lower gripper cam 230 fixed to the shaft 227 and the shaft 2
By swinging the upper gripper cam 231 fixed to 28 in the direction of the arrow, swinging in the directions of the arrow D and the arrow C is repeated (solid line and broken line diagram). Further, the spring member 233 urges the cam portion 242a of the lower gripper 242 to the lower gripper cam 230, and the spring member 232 urges the cam portion 241a of the upper gripper 241 to the upper gripper cam 231 to contact the upper gripper and the lower gripper. The contact pressure is controlled to be substantially constant.

Next, a description will be given of a roller pair for conveying the sheet bundle once stored in the intermediate tray 201 to the stack tray 202.

As shown in FIG. 8, a pair of upper and lower transport rollers 243 is provided between the intermediate tray 201 and the stack tray 202.
244 are installed. Two lower transport rollers 243 are provided on a lower transport roller shaft 245 supported by the front and rear side plates 203 and 204, while an upper transport roller 244 is mounted on an upper transport roller shaft 246 supported by swing arms 247 and 247.
Are provided at positions facing the lower transport roller 243. A roller 248 is attached to one end of the swing arm 247, and a swing cam 249 abutting on the roller 248 is fixed to a swing cam shaft 250 supported by the front and rear side plates 203 and 204. The swing cam shaft 250 is driven by a motor (not shown) and rotates in the direction of the arrow, thereby swinging the upper swing arm 247 about the shaft 247 in the direction of the arrow G (solid and broken lines). The spring member 251 is provided with a roller 248.
Is constantly urged against the swing cam 249, and the upper transport roller 244 is
And the contact pressure of the lower conveying roller 243 is made substantially constant.

The material of the upper transport roller 244 is rubber (hardness of about 40 ° to 60 °).
43 is made of urethane foam (hardness: about 10 ° to 20 °)
It is. Further, the upper conveying roller 244 has a friction coefficient enough to surely convey the sheet without slippage, and the lower conveying roller 243 is formed such that the friction coefficient between the sheet and the lower conveying roller is lower than the friction coefficient between the sheets. I have. The upper transport roller 244 and the lower transport roller 243 have the same outer diameter, and both rollers are rotated at a constant speed in the direction of the arrow by a motor and transmission means (not shown).

Next, a description will be given of a holding arm for temporarily holding the rear end of the sheet bundle (the leading end during the conveyance) when the sheet bundle is conveyed from the intermediate tray 201 to the stack tray 202.

As shown in FIG. 8, the holding arm 252 is located below the intermediate tray tip 201c.
2a is located in the middle of the nip position between the lower transport roller shaft 245 and the upper and lower transport rollers. The holding arm 252 is a shaft 2
54 (see FIG. 5), and the holding arm 252
When the solenoid 253 connected to the rear end is turned on and off, the solenoid 253 swings in the direction of arrow F (solid line and broken line diagram) with the shaft 254 as a fulcrum (see FIG. 8).

Further, the left side plate 206 of the stacking device 200
Is mounted with a reference plate 255 for aligning the leading end of the sheet bundle conveyed to the stack tray 202, and a sensor 256 for detecting the stack tray surface is provided at a predetermined position of the reference plate 255. When the solenoid 253 is in the ON state, the reference plate 255 sets the distance between the tip of the holding arm 252 and the reference plate 255 to l ₂ , sets the distance between the lower conveying roller 243 surface and the reference plate 255 to l ₁ , Assuming that the length of the bundle in the transport direction is l, the bundles are arranged in a relationship of l ₁ >l> l ₂ .

An operation flow will be described based on the configuration of the above apparatus.

Here, first, the sheet bundle is sorted by the sorting apparatus 10.
An example in which the staple unit 400 does not perform staple binding will be described.

Sheets on which images have been formed by the set number of images by the image forming apparatus 300 are sequentially discharged to and stored in bin trays B and are aligned by the above-described alignment means (see FIG. 6). When the alignment is completed, the lowermost bin tray storing the sheet bundle is moved to the intermediate tray 20 of the stacking device.
It moves by the rotation of the lifting / lowering rotating body 3 to a position facing 1. Subsequently, as shown in FIG. 11, the alignment reference member 13 stopped at the alignment reference position returns to the standby position a, and then the alignment rod 21 moves all the sheet bundles with the rotation of the pulse motor 19. It moves to the pushing position c while abutting on the side end. Due to the movement of the alignment rod 21, the other side end of the sheet bundle is pushed toward the near side of the sorting apparatus 100 and enters the inside of the rear side plate 204 of the stacking apparatus 200. In this case, FIG. 11 and as shown in the FIG. 12 is a main cross-section, the gripper device 220 under the gripper at its home position H ₁ of the stack apparatus 200 inner portion 242 and the upper gripper 241
Is waiting in an open state, and the first
Of the sheet bundle S ₁ is interposed between the lower gripper 242 and the upper gripper 241. Thereafter, the 180 ° rotation of the upper gripper cam 231 and the lower gripper cam 230, the upper gripper 241 and the lower gripper 242 starts swinging shaft 229 as a fulcrum, reliably sandwich the side edge corners M of the sheet bundle S ₁ ( See FIG. 13).

Next, as shown in FIG.
0 while holding the sheet bundle S ₁ by the above-described means.
It is supported on the rails 221 and 222 to transport the sheet bundle S ₁ to the intermediate tray 201. At this time, the upper conveying roller 244 is supported to the swing arm 247, located in a position spaced from the lower conveyor roller 243, the sheet bundle S ₁ is intervene portion between該離.

In the transfer, the corner M at the side end of the sheet bundle S ₁ is securely held by the upper and lower grippers, and the rear end is located at the rear end stopper B ′ of the bin tray B and the intermediate tray 201 located on substantially the same plane. for guided to the trailing end stopper 201b, beam deviation of the sheet bundle S ₁ caused by the movement is little. When the sheet bundle S ₁ is is completely placed on the intermediate tray 201 moves gripper device 220 is stopped (position H _2).

Next, as shown in FIG.
31 and the lower gripper cam 230 rotate again by 180 ° to release the clamping pressure between the upper gripper 241 and the lower gripper 242. The lower surface of the sheet bundle S ₁ with the above operation, abuts against the lower conveying roller 243. Note that the holding arm 252 described above continues to retract at the position shown by the broken line in FIG.

[0049] Also, if, when the sheet bundle to be transferred is present several portions, by the rotation of the elevating member 3 at this time bin tray B ... was one step lowered, the sheet bundle S ₂ is high gripper device 220 It can be adjusted.

Subsequently, the swing arm 247 starts swinging by the above-described means, and the upper conveying roller 244 applies a predetermined pressing force f ₀ to the sheet bundle S ₁ . At this time, the hardness of the lower transport roller 243 is
As shown in FIG. 16, the sheet near the upper conveying roller 244 generates the bending w, but the sheet near the lower conveying roller 243 has the lower conveying roller 2 as shown in FIG.
The pressing force f ₀ is absorbed by the action of crushing 43 itself, and no bending occurs. The radius of curvature of the flexure w increases as the sheet moves from the upper sheet to the lower sheet. That is, as the sheet moves from the upper sheet to the lower sheet, the transport amount at a predetermined angle of rotation of the transport roller also increases. Here, the transfer of the lowermost sheet of the sheet bundle S ₁ is, as it becomes larger than that by the lower conveying roller 243 described above, the friction coefficient of the lower conveying roller 243 surface is formed lower than the friction coefficient of the sheet Therefore, the lowermost sheet is fed by sliding the lower transport roller 243. Since the drive is also transmitted to the lower transport roller 243, both transport rollers have a sufficient transport force to transport a large number (50 to 100) of sheet bundles.

The sheet bundle S ₁ conveyed by the two transport rollers has its downwardly protruding tip first abutting against the reference plate 255 and stops suddenly (FIG. 18A). Then
The upper sheet is still moving in the transport direction due to the inertial force, and finally comes into contact with the reference plate 255 and stops (FIG. 18B). In this way, all the sheets of the sheet bundle S ₁ are aligned by abutting their leading ends against the reference plate 255,
The sheets are stacked on the stack tray 202 (FIG. 17). As described above, the sheet bundle S ₁ is once accommodated in the stack tray 202 base 205 for supporting the stack tray 202 is the sensor 256 by the aforementioned lifting means is lowered until it detects the sheet surface of the sheet bundle S _1.

Next, the operation in the case where there are a plurality of sheet bundles to be transferred will be described (second and subsequent copies).

As described above, the second sheet bundle S ₂ is
It is adjusted in advance to the height of the gripper device 220, and is securely held between the upper gripper 241 and the lower gripper 242 as in the case of the sheet bundle S ₁ , and is transported in the direction of the intermediate tray 201. Here, as shown in FIG. 19 is a simplified top view of a stacking device 200, when the gripper device 220 is transferring the sheet bundle S _1, compared to that moved to the position H ₂ (two-dot chain line), the sheet during the transfer of the bundle S _2, is in a point to end a movement at a position nearer than the position H ₂ by a distance L (position H _3), subsequent operations are all both common. FIG. 20 which is a front view of FIG.
As shown in, the tip of the sheet stack S ₂ is for progresses while sliding on the sheet bundle S _1, the uppermost sheet of the sheet bundle S ₁ is subjected to a force is supported by the reference plate 255 is distal to the transport direction Because it is, it does not move. As shown in FIG. 21 is a simplified side view of a stacking device 200, the sheet bundle S ₂ is placed with the offset amount L ₁ on the sheet bundle S _1. Thereafter, by changing the stop position of the gripper device 220 for each sheet bundle on the bin tray adjacent to the sorting device 100, all the sheet bundles are spatially divided and stacked horizontally on the stack tray as shown in FIG. You.

Next, an image is formed by the image forming apparatus 300, the sorting is completed by the sorting apparatus 100, and a sheet bundle composed of a small number of sheets (2 to 5 sheets) stored on the bin tray is stapled by the stapling unit. The case of performing staple binding will be described.

Sheets on which images have been formed by the number of images set by the image forming apparatus 300 are sequentially discharged to and stored in bin trays B and aligned by alignment means (FIG. 6). At this time, the first tray 401 (see FIG. 7) on which the stapler ST is fixed is waiting at a position (FIG. 6) where the stapler ST does not hinder the sorting. When the alignment of all the sheets is completed, the bin tray on which the sheet bundle is stacked is moved to a position facing the stapler ST by the rotation of the elevating and lowering rotator 3, and a stapling ON signal is sent to the staple unit.

In response to this signal, the first tray 401
Moves to Y ₃ direction by the rotation of the arrow direction of the pinion gear 404 due to the driving of the motor 403 (FIG. 23). When the first tray 401 moves by a predetermined amount and the sheet bundle on the bin tray is inserted into the upper and lower jaws of the stapler ST, the upper and lower jaws clinch and bind the sheet bundle by staple.
The tray 401 returns to the standby position again.

Subsequently, the bin tray is raised or lowered one step by the rotation of the elevating and lowering rotating body 3, and all the sheet bundles are stapled. Thereafter, the operation from when the gripper device 220 moves while pinching the bound sheet bundle to when it is placed on the intermediate tray 201 is the same as in the case of the unbound sheet bundle. The binding sheet bundle S ₁ ′ placed on the intermediate tray 201 is transferred to the stack tray 202 by rotation of the upper and lower transport roller pairs 243 and 244, but the rear end of the sheet bundle is securely bound. The bundle shift in the transport direction as described above does not occur. At this time, the holding arm 252 is connected to the solenoid 2
53 is turned on, and the leading end moves to a position protruding from the conveying roller surface. Accordingly, as shown in FIG. 24, the stapled sheet bundle S ₁ ′ transferred to the stack tray 202 abuts the leading edge of the stapled sheet against the reference plate 255 so as to be aligned.
The stapled to rear end portions are held by the holding arm 252 (T ₁ denotes a staple). Then, as shown in FIG. 25, the solenoid 253 is turned off, and the holding arm 252 is turned off.
Moves to the retreat position with the shaft 254 as a fulcrum. By this operation, the rear end of the stapled sheet bundle S ₁ ′ held is
It falls on the stack tray 202. Then, the stack tray 202 is lowered until the sensor 256 detects the paper surface of the bound sheet bundle S ₁ ′.

Next, the transfer operation of the second copy and thereafter will be described. The second binding sheet bundle S ₂ ′ is also transferred to the stack tray 202 in the same manner as the _first binding sheet bundle S ₁ ′ (FIG. 26). At this time, the sheet bundle S ₂ 'tip of the sheet bundle S _1' to abut at a point beyond the staples T ₁ of the sheet bundle S ₂ 'of the tip and the sheet stack S _1' of staples T ₁ of the There is no adverse effect due to interference. In addition, since the leading end of the sheet bundle S ₁ ′ is supported by the reference member 255, it is possible to prevent the sheet bundle S ₂ ′ from being entrained. Further, even if the trailing end of the sheet bundle S ₂ ′ passes through the nip of the pair of conveying rollers 243 and 244, the trailing end (the binding needle T ₂ ) is temporarily separated from the sheet bundle S ₁ ′ by the holding arm 252. Therefore, adverse effects such as bending beam deviation and the rear end of the rear end is generated by interference staple T ₂ and the sheet bundle S ₁ 'is prevented. Thereafter, the solenoid 253 is turned off, and the rear end of the stapled sheet bundle S ₂ ′ falls onto the sheet bundle S ₁ ′. Thereafter, the binding sheet bundle on all the bin trays is transferred to the stack tray 202 by the above operation.

As shown in FIG. 27, when a large number of stapled sheet bundles each composed of a small number of sheets (2 to 5 sheets) are stored, the group of sheet bundles has a front end portion corresponding to the binding needles at the rear end. In order to increase the height as compared with the above, a loop portion R is formed. However, since the leading end of the sheet bundle group is continuously supported by the reference member 255, the alignment state on the stack tray 202 is maintained.

Further, the binding sheet bundle in the above embodiment is one in which two rear end portions are staple-bound. However, by operating only one of the two staplers, one binding is performed. It is naturally possible, and the transfer operation at that time is exactly the same as in the above example. As shown in FIG. 7, the staple unit 400 is supported on a rail 405 and the motor 4
The drive 07 is movable in the Y ₂ direction, the various staple position (one place binding, two places binding)
Or, it is moved according to various sheet sizes.

The sorting apparatus used in the above embodiment is a bin-movable sorter that moves the bin tray group to the sheet discharge port of the image forming apparatus. A so-called bin-fixed sorter comprising a distributing device for distributing discharged sheets to each bin tray may be used. In this case, the stack tray 202 of the stack device 200, the gripper device 220, the transport roller 2
Reference numerals 43 and 244 are configured to be movable to positions facing the respective bin trays.

Another Embodiment In the apparatus of the above embodiment, when the unbound sheet bundle is transported by the upper and lower transport rollers 243 and 244, the transport amount of the lowermost sheet is larger than the transport amount of the lower transport roller 243. Therefore, slippage between the transport roller 243 and the sheet occurs. Although the above-described apparatus has the advantages of simplification of the configuration and cost reduction, it is also conceivable that the lower roller may be worn out earlier and the sheet may be damaged. Therefore, as shown in FIG. 28, a one-way clutch 245a that makes the transport direction free may be interposed on the shaft 245 of the lower transport roller 243. The one-way clutch 245a absorbs the slip between the lower transport roller 243 and the sheet.

In the following, another example of the transfer means for increasing the transfer amount of the conveyed sheet bundle in the lower sheet will be described.

The structure of the apparatus is almost the same as that of the above-described embodiment, but as shown in FIG.
The nip position of 244 is set to the horizontal plane 201 of the intermediate tray 201.
Each is installed so that it may become lower than C. The material of the lower transport roller 243 in this apparatus is the same rubber member (hardness 40 ° to 60 °) as the upper transport roller 244 in the above embodiment.
°). And the shaft 245 of the lower transport roller 243
Is provided with a one-way clutch 245a as described above.

With the above configuration, the upper and lower transport rollers 24
As shown in FIG. 29, the sheet bundle nipped by the sheets 3 and 244 is entirely wound around a part of the upper conveying roller surface. The wound sheet bundle has a larger radius of curvature as the lower sheet, and in this state, the upper and lower transport rollers 243,
When the 244 is rotated in the direction of the arrow, the lower the sheet, the larger the transport amount, and finally the reference plate 255 located upstream.
Abut. The difference in the transport amount between the lowermost sheet of the sheet bundle and the lower transport roller 243 is absorbed by the one-way clutch 245a. Thereafter, the upper sheet abuts against the reference plate 255 due to the inertial force, and the operation of alignment is the same as in the previous embodiment.

Further, in the above configuration, after the sheet bundle is nipped by the transport roller pairs 243 and 244, the sheet surface of the stack tray 202 is raised above the nip of the transport roller pairs 243 and 244 and transported (FIG. 30). The winding action on the upper conveyance roller 244 is strengthened, and the advance of the lower sheet is remarkable.

As a means for increasing the advance of the lower sheet, the peripheral speed of the lower transport roller 243 during transport may be set higher than the peripheral speed of the upper transport roller 244. In the above configuration, the outer diameter of the lower transport roller 243 is
4 (the driving means for rotating both rollers rotates at a constant speed). Further, the outer diameters of the two transport rollers 243 and 244 are designed to be equal, and the lower transport roller 243 is driven by driving means for rotating both rollers.
May be increased.

In the above-described embodiment, the sheet is transferred from the bin tray to the stack tray via the intermediate tray. However, the present invention is not limited to the above configuration.

For example, as shown in FIG.
Roller pairs 243 and 24 arranged in parallel with the side end of
4 and a stack tray 202 that rises and falls directly downstream of the pair of conveying rollers 243 and 244 may be provided. The same members as those in the above-described embodiment have the same functions, and the respective operations are substantially the same as those in the above-described embodiment.
Here, the conveying roller pairs 243 and 244 change the discharge speed for each sheet conveyed from each bin tray, and a reference plate 255 located downstream of the roller pairs 243 and 244 is driven in accordance with the discharge amount. The sheet bundle is supported by the guide 202a and converted into a solid line position and a broken line position by the unit, whereby the sheet bundle whose front end is abutted and aligned with the reference plate 255 is spatially sorted as shown in the figure.

Further, an embodiment in which the reference plate 255 of the above apparatus is fixed and the sheet bundle on the stack tray is spatially divided will be described below. In the present apparatus shown in FIG.
The reference plate 255 is fixed at a predetermined position downstream of the stack tray 202. The stack tray 202 is movable in the direction perpendicular to the sheet conveying direction of the pair of conveying rollers 243 and 244 in addition to the elevating operation. Then, by moving the stack tray 202 in the direction of the arrow for each sheet bundle to be conveyed, the sheet bundle on the stack tray 202 abuts against the reference plate 255 and is sorted and stacked spatially. In this apparatus, even if the sheet bundle already stacked on the stack tray 202 abuts on the next sheet conveyed by the pair of rollers 243 and 244, the leading end is always supported by the reference plate 255. No bundle shift such as feeding occurs.

Next, an embodiment of the second invention will be described with reference to FIGS.

In the embodiment of the present invention (FIGS. 1 to 32), after the sheet bundle is aligned on the bin tray of the sorting apparatus 100 by swinging the aligning rod 21, the aligning rod 21 is further swung. Although the sheet bundle side ends on all the bin trays are pushed out to the stacking device 200 side in a lump, the pushing out of the sheet bundle may be a successive process per one bin.

For example, as shown in FIGS. 37 and 7, the rear end of the sheet bundle stored in the bin tray B is
Lower jaw (anvil) ST ₁ and upper jaw (head) ST
_In the state clinched by ₂ , the staple unit 40
0 whole By moving while being supported by the Y ₃ direction rail 405 by a motor 407, a side edge portion of the sheet bundle can be conveyed to the stack unit 200 direction. Subsequent operations are exactly the same as in the above embodiment. Also whether the sheet bundle is stapled, the lower jaw ST ₁ and the upper jaw S
Due clinching pressure of T _2, clinching weak pressure when transferring the sheet bundle.

Next, another embodiment using a reference plate for further improving the consistency of the sheet bundle stored in the stack tray 202 will be described with reference to FIG. Note that the same reference numerals as those in the above-described embodiment denote the same members and operate in the same manner.

FIG. 38 is a simplified front view of the stacking device 200. In the reference plate, two pins 255d provided on a substrate 255a are fitted into fitting holes (not shown) of the left side plate 206. The contact member 255b is adhered to almost the entire surface of the substrate 255a on the sheet contact side. The contact member 255b is made of rubber,
It is formed of an elastic body such as a sponge. Further, a rack gear 255C is engraved below the substrate 255a, and a pinion gear 255e attached to an output shaft of a motor 255f fixed to a frame of the stack device 200.
Is engaged. The arrow I of the motor 255f
The reference plate reciprocates in the direction of arrow G by the rotation in the direction.

An operation flow based on the above configuration will be described.

The first sheet bundle S ₁ is the same as in the previous embodiment.
The (unstitched bundle) is placed on the stack tray 202 by the rotation of the conveying roller pairs 243 and 244. Here, the leading end of the sheet bundle S ₁ is abutted to the abutment member 255b is abutting member 255b as described above is an elastic body, to relieve the impact at the time of abutment, the sheet contact member 255
There is almost no rebound or separation from b, and the consistency is improved.

Next, the base 20 for supporting the stack tray
5 is lowered to the plane of the sheet bundle S ₁ with the loading of the next sheet bundle to the sensor 256 detects, when the downward remains in FIG 38 is performed, the sheet bundle S ₁ tip and the contact member There is a risk that a bundle shift may occur due to the rubbing with 255b. Therefore, as shown in FIG. 39, the reference plate 255 'is moved to the left in the figure, after the tightening become separated sheet bundle S ₁ and the contact member 255b, the descent of the base 205 is started. When the sensor 256 detects the sheet surface of the sheet bundle S _1, the base 20
5 is stopped, the reference plate 255 'is returned to the alignment position, ready for the transfer of the next sheet stack S ₂ (Figure 40). By repeating the above operation, all the sheet bundles are stored in the stack tray 202.

When there are various sizes of the sheet bundle stored in the stack tray 202, the reference plate 255 'may be transferred to an optimum position according to the sheet bundle size.

Further, another embodiment capable of binding a sheet bundle composed of a large number of sheets will be described below. In the above embodiment, the interval between the bin trays arranged in the vertical direction is appropriately determined according to the size of the apparatus, and the number of sheets accommodated in the interval is limited. The number of sheets that can be accommodated in one bin tray in the above-described embodiment is, for example, 50 sheets, and the electric stapler that performs binding also performs staple binding of up to 50 sheets.

Therefore, even if the operator attempts to sort the image forming sheets for 51 or more originals, the sorting device stops the operation after the 50 sheets have been sorted, and
The operator must rely on the operator to remove the sheets stored in the bin tray.

Even if the interval between bins is widened and the number of sheets stored per bin tray is increased to 51 or more, sorting is possible, but the above-mentioned electric stapler cannot perform staple binding. A stapler, for example, capable of stapling 51 or more sheet bundles, for example, a 100-sheet binding stapler is considerably larger than the 50-sheet binding stapler, and is very difficult to arrange inside the sorting apparatus.

In the following description, the above-mentioned problem is solved by disposing the 100-sheet binding stapler at a position facing the intermediate tray in the sheet post-processing apparatus of the above embodiment.

FIG. 41 shows the above configuration in detail, and shows a cut-out portion 201 provided at the front corner of the intermediate tray 201.
A 100-sheet stapler 450 is arranged at d. 1
The lower jaw 452 of the 00-sheet binding stapler 450 is fixed substantially flush with the intermediate tray 201, and the upper jaw 451 facing the lower jaw swings in the direction of the arrow to lower the lower jaw 452 and the upper jaw 45.
1 to perform staple binding of a sheet interposed between the sheets.

Next, a description will be given of the operation of using this apparatus to sort, for example, two copies of 70 originals and bind them with staples. First, the operator places a document on the document table 321 of the automatic document feeder 320 shown in FIG. 2, and sets the number of documents (70 sheets), the number of sorts (2 copies), and the presence or absence of staple binding (yes). After setting, etc., press the operation start key. The placed documents are sent to the predetermined position on the platen glass in order from the bottom,
Exposed. The 50th copy sheet from the bottom of the original is sorted into the second (bin tray B ₂ ) and the fourth (bin tray B ₄ ) from the top of bin trays B... . Also, from the bottom of the manuscript 51
The 70th to 70th copy sheets are sorted into the first sheet (bin tray B ₁ ) and the third sheet (bin tray B ₃ ) from the top of bin tray B. After the above sorting, the staple unit 400 installed in the sorting apparatus 100
Is prohibited, and there is no staple binding here.

The sheet bundle S _A placed on the _fourth bin tray B ₄ is transferred to the intermediate tray 201 by the same means as described above.
Is transported and stored at a predetermined position. At this time, the sheet bundle S
_The corners of the front and rear ends of _A are the stapler 45 with 100 sheets.
0 is inserted between the lower jaw 452 and the upper jaw 451. Subsequently, the sheet bundle S placed on the _third bin tray B3
_B was transferred by the same manner as described above means the intermediate tray 201 directions are accommodated in the sheet bundle S _A at the same position. That is, the sheet bundle S _A and the sheet bundle B _B will snap four corners, 10
Interposed between both jaws of the zero-sheet stapler 450 (FIG. 4)
1). Next, the operation start signal is sent to the 100 sheets stapler 450, upper jaw 452 is swung in the direction of the arrow, bound together the sheet stack S _A and the sheet bundle S _B. At this time, the page order of the bound sheet bundle S _AB is determined by the automatic document feeder 3.
The original is the same as the original placed on the document 20.

The sheet bundle S _AB is then conveyed to and stored in the stack tray 201 by the conveying roller pairs 243 and 244 as in the above-described embodiment.

[0088] Similarly, the second sheet bundle S _d placed on the bin tray B ₂ sheet bundle placed on the S _C and 1 sheet of bin trays B ₁ of the sheet of the sheet bundle S _c below Bundle S
_The sheets are stored in the intermediate tray 201 with _{d facing} upward, bound by a 100-sheet binding stapler 450, and transferred onto the sheet bundle S _AB .

The above set values are for the purpose of simplifying the description, and are not limited thereto.

When the set value before the start of the operation is “absence” of the staple binding, it is sufficient that the two sheet bundles are only combined on the intermediate tray.

In the above-described apparatus, a sheet bundle temporarily divided into booklets by a bin tray is combined by an intermediate tray into a booklet, and stored in a stack tray.

Further, the binding means used in the above-described apparatus is a stapler for stapling a sheet bundle, but may be a bookbinding means for gluing and binding one side end of the sheet bundle.

The above-mentioned 100-sheet stapler 450
Can be reciprocated in the direction of the arrow shown in FIG. 41, so that an arbitrary number of bindings can be performed at an arbitrary position. For example, as shown in FIG. 41, if a cutout portion 201e is provided in the example of the rear end of the intermediate tray 201, the 100-sheet binding stapler 450 moves to a position corresponding to the cutout portion 201 and performs two stapling operations. I can do things.

[0094]

According to the present invention, there are provided a plurality of sheet trays capable of sorting and storing sheets, sheet discharging means for discharging the sheets to the sheet tray, and a sheet stacking section for taking out and stacking the sheets on the sheet tray. A sheet post-processing apparatus comprising: a first sheet conveying unit configured to convey a sheet on the sheet tray, wherein the sheet stacking unit conveys a sheet on the sheet tray;
A first sheet stacking tray for stacking the conveyed sheets, a second sheet conveying unit for conveying the sheets on the first sheet stacking pan, and a second sheet stacking tray for receiving and stacking the conveyed sheets; The first sheet stacking tray is provided at a position substantially orthogonal to the sheet advancing direction on the sheet tray with respect to the sheet tray, and the second sheet stacking tray is provided with respect to the first sheet stacking tray. It is configured to be provided at a position substantially orthogonal to the sheet advancing direction on the first sheet stacking tray. This makes it possible to arrange the so-called stack tray in a position that is easy for the user to handle,
Operability can be improved.

Further, by providing an alignment reference plate which is in contact with the leading end of the sheet discharged to the second sheet stacking tray by the second sheet conveying means, the sheet bundle on the so-called stack tray is aligned. It is possible to do. Also, by locking the leading end of the sheets already stored on the stack tray with the reference plate, the loaded stack is brought into alignment with the next sheet bundle to be conveyed to the stack tray. Can hold. Further, the second sheet conveying means is constituted by a pair of rollers configured such that the lower side of the sheet bundle is advanced when conveying a plurality of sheet bundles, so that the lower part of the sheet bundle firstly contacts the reference plate. Since the upper sheets are brought into contact with each other and sequentially moved to the reference plate by the inertial force, the positioning and alignment of all the sheets can be performed more effectively.

Further, the sheet bundle whose rear end is bound by the binding means or the like on the bin tray is conveyed by the second sheet conveying means starting from the unbound front end which is opposed to the bound rear end, and is conveyed to the reference plate. Since the contact and alignment are performed, the stackability on the stack tray can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire image forming apparatus including a sheet post-processing apparatus according to the present invention.

FIG. 2 is a front sectional view of the same.

FIG. 3 is an enlarged front sectional view of the sorter unit.

FIG. 4 is a perspective view showing a main part of the sorter unit.

FIG. 5 is a plan view of the sheet post-processing apparatus.

FIG. 6 is an explanatory diagram of the operation.

FIG. 7 is an enlarged perspective view of the same stapler.

FIG. 8 is a front sectional view of the sheet post-processing apparatus.

FIG. 9 is a sectional view taken along line LL of FIG. 8;

FIG. 10 is a front view of the sheet bundle nip device.

11 is an operation explanatory diagram of FIG. 5;

FIG. 12 is an operation explanatory diagram of FIG. 8;

FIG. 13 is an explanatory diagram of the same operation.

FIG. 14 is an operation explanatory diagram of FIG. 5;

FIG. 15 is an operation explanatory view of FIG. 8;

FIG. 16 is a schematic diagram showing a state in which a sheet bundle is transferred.

FIG. 17 is an operation explanatory view of FIG. 8;

FIG. 18 is a schematic diagram illustrating the sheet bundle alignment operation.

FIG. 19 is an enlarged plan view of a principal part for explaining the operation of FIG. 5;

FIG. 20 is an explanatory view of the operation of the main part of FIG. 8;

FIG. 21 is a left side view showing the loaded state.

FIG. 22 is a left side view showing the loaded state.

FIG. 23 is an operation explanatory view of FIG. 5;

FIG. 24 is an explanatory view of the operation of the main part of FIG. 8;

FIG. 25 is an operation explanatory view of the same.

FIG. 26 is an operation explanatory view of the same.

FIG. 27 is an explanatory diagram of the same operation.

FIG. 28 is a schematic diagram illustrating a state of transporting a sheet bundle according to the second example.

FIG. 29 is a schematic view showing a state of transporting a sheet bundle of the third example.

FIG. 30 is a schematic diagram illustrating a state of transporting a sheet bundle according to a fourth example.

FIG. 31 is a perspective view showing another example of the sheet post-processing apparatus.

FIG. 32 is a perspective view showing still another example.

FIG. 33 is a plan view showing a conventional example.

FIG. 34 is a side view showing the operation of the conventional example.

FIG. 35 is a schematic view showing a state of transporting a sheet bundle according to a conventional example.

FIG. 36 is a side view showing an alignment state of a sheet bundle according to a conventional example.

FIG. 37 is a plan view of a sheet post-processing apparatus according to the present invention (second).

FIG. 38 is a front sectional view showing the matching device.

FIG. 39 is an operation explanatory view of FIG. 38;

40 is an operation explanatory view of FIG. 38. FIG.

FIG. 41 is a perspective view showing a second embodiment.

FIG. 42 is a front view showing the operation of the conventional example.

FIG. 43 is an explanatory diagram of the same operation.

FIG. 44 is a view showing another conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Sorting device 200 Stacking device 300 Image forming device 400 Staple unit B Bin tray 131 Reference rod 211 Alignment rod 201 Intermediate tray 202 Stack tray 220 Gripper device 244, 245 Transport roller pair 256 Reference plate

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B65H 39/00-39/16 B65H 31/00-31/40 B65H 29/00-29/70

Claims (8)

(57) [Claims] 1. A plurality of sheet trays capable of sorting and storing sheets, a sheet discharging unit for discharging the sheets to the sheet tray, and a sheet stacking unit for taking out and stacking the sheets on the sheet tray. In the sheet post-processing apparatus, the sheet stacking unit includes: a first sheet conveying unit configured to convey a sheet on the sheet tray; a first sheet stacking plate configured to stack the conveyed sheet; And a second sheet loading tray for receiving and loading the transported sheet. The first sheet loading tray is placed on the sheet tray with respect to the sheet tray. The second sheet stacking plate is provided at a position substantially orthogonal to the sheet advancing direction, and the second sheet stacking plate is substantially orthogonal to the first sheet stacking plate with respect to the sheet advancing direction on the first sheet stacking plate. Sheet post-processing apparatus, characterized in that provided in the position. 2. The sheet tray according to claim 2, wherein the sheet tray is inclined.
A first sheet stopper is provided below the inclined sheet receiving tray, and the first sheet loading tray is disposed to have an inclination substantially parallel to the sheet receiving tray, and a first sheet stopper is disposed below the inclined first sheet loading tray. The sheet post-processing apparatus according to claim 1, wherein a two-sheet stopper is provided, and the second sheet stacking tray is disposed substantially horizontally. 3. An alignment reference plate according to claim 1, wherein an alignment reference plate is provided for contacting a leading end of a sheet discharged to said second sheet stacking tray by said second sheet conveying means. Sheet post-processing equipment. 4. A sheet after sheet according to claim 3, wherein said second sheet conveying means comprises a pair of rollers configured to advance a lower side of the sheet bundle when conveying a plurality of sheet bundles. Processing equipment. 5. The sheet after sheet according to claim 1, wherein the amount of sheet conveyed by the first sheet conveying means is made different for each sheet bundle conveyed. Processing equipment. 6. After the at least two sheets are stacked at the same position on the first sheet stacking tray, the second sheet is stacked.
The sheet post-processing apparatus according to any one of claims 1 to 4, wherein the sheet is conveyed and stacked on a sheet stacking tray. 7. The sheet post-processing according to claim 1, further comprising a binding unit configured to perform a binding process on a sheet stacked on the first sheet stacking tray. apparatus. 8. After at least two sheets of sheets are stacked on the first sheet stacking tray at the same position, a binding process is performed by the binding means, and then the sheet is conveyed and stacked on the second sheet stacking tray. 8. The sheet post-processing apparatus according to claim 7, wherein the sheet post-processing is performed.