JPH0616326A - Sheet after-treatment device - Google Patents

Abstract

PURPOSE:To increase the number of sheet, which can be transferred and housed, in a stack device, which is attached to a fixed bin type sorter and which houses sheet, without enlarging a device. CONSTITUTION:A device for the sheet after-treatment is provided with plural bin trays B1-B10, which can house the sheets and which are fixed in the vertical direction, and a carrying part 213, which moves to the position corresponding to each bin tray to carry the sheet to a stack tray 220. Even in the case where the paper surface of the stack tray 220 is raised, all of the sheets can be transferred by transferring the sheet bundle to the stack tray 220 with the carrying part 213 in order from the lower of the sheet placing bin trays B1-B10. Furthermore, the sheet housing quantity can be increased by using the bin tray positioned upper than the paper surface of the stack tray 220 to house the sheet.

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, and more particularly, to one or more trays for sequentially receiving sheets such as copy sheets discharged from an image forming apparatus such as a copying machine or a printing machine after image formation. The present invention relates to a sheet post-processing apparatus that includes a sorting device that is classified and stored (hereinafter referred to as a “bin tray”) and a stacking device that stacks a sheet bundle.

[0002]

2. Description of the Related Art Conventional sorting devices for distributing and storing sheets can be roughly classified into a bin-moving sorter and a fixed-bin sorter.

In the bin-moving sorter, the entire bin tray stacking device for stacking bin trays vertically is controlled to move with respect to the sheet discharge port of the image forming apparatus, and the sheet inlet portions of the individual bin trays are sequentially positioned. This is a system for distributing sheets to individual bin trays.

The bottle fixed sorter is a sheet path in which the bin tray stacking body is immovable and is selectively switched from the sheet discharge port of the image forming apparatus to the sheet inlet portion of each bin tray of the bin tray stack by a guide plate, a deflecting plate and the like. This is a system in which a mechanism is formed and the sheets discharged from the sheet discharge port of the image forming apparatus via the sheet path mechanism are sequentially conveyed and distributed to individual bin trays.

Then, as shown in FIG. 15, the bin tray B is
A stack device A attached to the above sort device is considered for the purpose of classifying and storing sheets in excess of the numbers a to Bj. The stacking device A includes a stack tray Aa for stacking a bundle of sheets together and a conveying unit A for conveying the bundle of sheets from the bin trays Ba to Bj to the stack tray Aa.
b and. The positions of the stack tray Aa and the transporting means Ab are controlled by means for raising and lowering each of them so that the stack of sheets placed on each bin tray can be transferred. That is, the stack tray Aa is arranged from the lowest bin tray Bj to the highest bin tray B of the bin tray stack.
The solid line position (the lowest bin tray Bj
And the position between the floor surface) and the two-dot chain line position.

[0006]

However, when the sorter to which the stacking device is attached is the bottle fixed type sorter, there are the following problems.

(1) Since the lowermost bin tray Bj of the bin tray stack and the floor surface are positioned at a predetermined distance L shown in FIG. 15, the capacity of the sheet bundle stored in the stack tray Aa increases, and for example, the stack When the paper surface of the tray Aa is positioned between the bin tray Bh and the bin tray Bi as shown in FIG. 16, the bin tray Bi and the bin tray Bj are located.
The sheet bundle S placed on the sheet cannot be transferred to the stack tray.

(2) If the distance between the lowest bin tray Bj and the floor surface described in (1) above is enlarged, the entire apparatus becomes large in the bin arrangement direction, and in order to prevent the apparatus from becoming large, In order to increase the distance between the lower bin tray Bj and the floor surface, the total number of bin trays to be arranged must be reduced, or the arrangement interval of each bin tray must be narrowed. The reduction in the number of bin trays reduces the number of sortable copies, and if the arrangement interval of each bin tray is narrow, the sheet stackable capacity of each bin tray decreases.

Further, the bin-moving sorter has a problem that the bin tray stack must be moved up and down every time a sheet is discharged from the image forming apparatus, and vibration and noise are generated as the bin tray is stacked up and down. .

[0010]

Means (and Action) for Solving the Problems
It is intended to solve the problems that the above-mentioned conventional device has, and is a small sheet that can sort and store a sheet bundle exceeding the number of bin trays arranged in a fixed bin sorter. An after-treatment device is provided.

According to the present invention, in order to achieve the above-mentioned object, (1) a plurality of bin trays which are fixedly installed in an upper and lower multi-stage for accommodating sheets, sheet ejecting means for ejecting sheets to the bin trays, and the bin trays. And a conveyance unit that can move up and down to a position facing each other and that conveys sheets on the bin tray,
In a sheet post-processing apparatus including a stack tray that can move up and down to a position corresponding to the transport unit and that receives and stacks transported sheets, the transport unit includes a lower bin tray on which a sheet bundle is placed. By sequentially transferring the sheet bundle to the stack tray, all the sheets can be transferred even if the sheet storage capacity of the stack tray increases.

(2) Further, in the above apparatus, a paper surface position detecting means for detecting the paper surface at the lowest position of the stack tray accommodating the sheet bundle and a means for recognizing the number of bin trays located above the paper surface. By providing the stack tray, even if the sheet surface of the stack tray rises, the bin tray located above the bin tray can continue to store the sheets.

[0013]

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

FIG. 1 is a main cross section of a sheet post-processing apparatus embodying the apparatus of the present invention. The image forming apparatus 300 includes a sorting device 100 having a plurality of bin trays B ...
A stack device 200 for accommodating a sheet bundle is installed in front of the sorting device 100.

Since the configuration of the image forming apparatus 300 and the image forming process are well known, only the reference numerals of the main components will be described here. Reference numeral 301 is a platen glass (original platen glass), 302 is an original pressure plate, 303 is an optical system moving type original scanning mechanism section including an original illumination lamp, a moving mirror, an imaging lens, a fixed mirror, and the like, 304 is a rotary photosensitive drum, 305 is a charging device, 306 is a developing device, 307 is a transfer separation charging device, 308 is a cleaning device, 309, 3
10 is a first and second transfer sheet storage cassette, 31
1 is a sheet conveying device, 312 is an image fixing device, and 313 is a sheet discharge roller pair.

The sorting device 100 is disclosed in Japanese Patent Laid-Open No. 63-262.
This is similar to that disclosed in Japanese Patent No. 373, and will be briefly described here. B _{1 to} B ₁₀ are a plurality of bin trays that are fixedly arranged in upper and lower stages. 101 is the image forming apparatus 3
00 is a first distribution device capable of vertical movement control between the sheet discharge roller pair 313 side and the sheet tray side of the bin trays B _{1 to} B ₁₀ , and 105 is the first distribution device 101.
It is a second distribution device which is adjacent to the downstream of and is also vertically movable. The first distribution device 101 has a roller / roller pair 101a and 101b that holds and conveys a sheet, a rotation driving motor (not shown) thereof, a sensor 101c that detects the presence of the sheet, and the like. The belt 104 is attached and supported by a belt 104 that is suspended and stretched between the pulley 102 and the upper driven pulley 103, and is controlled to move up and down in accordance with the forward and reverse rotation of the belt 104 by the forward and reverse control of the drive pulley 102. Similarly, the second distribution device 105 holds the sheet.
It has a pair of roller / rollers 105a and 105b for conveyance, a rotation driving motor (not shown) thereof, a sensor 105c for detecting the presence of a sheet, and the like, and a suspension roller between a lower driving pulley 106 and an upper driven pulley 107. The stretched belt 108
And is supported by the drive pulley 106, and is controlled to move up and down in accordance with the forward and reverse rotation of the belt 108 by the forward and reverse control of the drive pulley 106. Next, collect the bin trays B _{1 to} B ₁₀ ,
The bin unit 105 including the aligning means for aligning the sheets stored in the bin tray will be described. As shown in detail in FIG. 2, the bin unit 105 is provided with an alignment reference member 108 that abuts against the sheet from the upper cover 106 to the lower cover 107. And the bottle unit 10
5, a rotation center shaft 111 having an upper end portion fixed to the upper arm 109 and a lower end portion fixed to the lower arm 110 has a rotation shaft 106a provided on the upper cover 106 and a lower cover 107.
It is rotatably supported by a rotary shaft (not shown) provided in the. The lower cover 107 has a fan gear 112.
However, the lower arm 107 is rotatably arranged around a rotation shaft provided on the lower cover 107, and the lower arm 110 is fixed to the fan gear 112. Further, a pulse motor 113 is arranged below the lower cover 107, and the pulse motor 1
A pinion 113 a fixed to the output shaft of 13 meshes with the fan-shaped gear 112. Each of the bin trays B is attached to the tip of the lower arm 110 and the tip of the upper arm 109.
Alignment rods 115 are installed so as to penetrate the notch 114 provided in the tray over all the bin trays.
Is configured to swing by the rotation of the fan gear 112. Further, a light shielding plate 116 is provided on a part of the lower arm 110, and the light shielding plate 116 rotates integrally with the lower arm 110, so that the arm 11 is attached to the lower cover 107.
The home position sensor 118 fixed via 7 is turned on and off.

The reference rod 1 is provided on the front side of the alignment rod 115.
Similarly to the aligning rod 115, 08 is arranged so as to pass through a notch 119 provided in all bin trays, and a fan gear 120 is fixedly provided at the lower end of the reference rod 108. The fan-shaped gear 120 is a rotary shaft 121 provided on the lower cover 107.
The upper arm 122 fixed to the upper end of the reference rod 108 is supported by the rotating shaft 123 provided on the upper cover 106. A pulse motor 124 is arranged on the lower cover 107, and a pinion gear 124 a fixed to the output shaft of the pulse motor 124 meshes with the sector gear 120 to rotate the sector gear 120, thereby rotating the reference rod 10.
8 swings. Further, a light shielding plate 125 is provided at the end of the fan-shaped gear 120 so that the home position sensor 126 arranged on the inner side of the lower cover 107 is turned on and off by the rotation of the fan-shaped gear 120. It is configured.

As shown in FIG. 3, which is an upper view of FIG. 2, when the copying operation of the image forming apparatus 300 is started, the standby position 1
The reference rod 108 waiting at 08a (the position of the chain line) moves in the arrow direction by the rotation of the pulse motor 124,
It stops at the alignment reference position 108b (position indicated by the solid line). After that, the sheet S on which the image is formed by the image forming apparatus 300 is formed.
Are discharged from the pair of discharge rollers 313 to the bin tray via the sheet distributing device 101 of the sorting device 100, and the bin tray B, which is arranged with the rear end stopper B ′ inclined downward, is moved to the rear end stopper B ′ by its own weight. Move towards.

Next, as shown in FIG. 4, the alignment rod 115 is moved by a predetermined amount in the arrow direction from the standby position 115a (the position indicated by the chain line) by the pulse motor 113 that rotates based on the pulse signal corresponding to the sheet size. (Solid line position), the reference bar 10 that stops the sheet at the alignment reference position 108b.
Press on 8.

The reference rod 108 continues to stop at the alignment reference position until all the sheets by the image forming apparatus 300 are stored in the bin tray B. However, the alignment rod 115 moves a predetermined amount and then ejects the next sheet. In preparation, it returns to the standby position 115a. By repeating the above-described operation, a sheet bundle composed of one or more sheets is placed on one bin tray at the side end with the reference rod 10.
8, the rear end is brought into contact with the rear end stopper B'and aligned. The aligning rod 115 penetrates all the bin trays, and the sheets S stored in other bin trays are similarly aligned.

Next, the structure of the stack device 200 will be described.

FIG. 5 is a main sectional view of the stacking device 200.
And the stacking device 2 as shown in FIG.
00 is an intermediate unit 210 that conveys a sheet bundle,
Stack tray 220 for stacking conveyed sheet bundles
It consists of and. The intermediate unit 210 is fixed to a belt 203 that is stretched around a driving lower pulley 201 and a driven upper pulley 202 that are arranged in a vertical frame of the stacking device 200. Then, the intermediate unit 210 is vertically moved and controlled by the forward and reverse rotations of the motor Ma that rotates the lower pulley 201. On the other hand, in the stack tray 220, the stack tray 200 is fixed to a belt 206 suspended between a driving lower pulley 204 and a driven upper pulley 205 arranged on a frame extending in the vertical direction, The vertical movement of the motor Mb that rotates the pulley 204 is controlled to move up and down.

The intermediate unit 210 includes an intermediate tray 211 that temporarily stores a sheet bundle, a gripper unit 212 that transfers the sheet bundle on the bin tray B to the intermediate tray 211, and a sheet on the intermediate tray 211. A transport unit 213 for transferring to the stack tray 220,
Composed of. The intermediate tray 211, and inclined parallel to the bin tray B ₁ .about.B _10, which is fixed to the frame of the intermediate unit 210 (not shown), the sheet stopper 211a is upright on the rear end. As shown in FIG. 7, the gripper unit 212 includes a belt 216 stretched between a front pulley 214 and a rear pulley 215, which are provided on both ends of a frame (not shown) extending in the front-rear direction of the intermediate unit 210 and are driven. The motor Md rotating the front pulley 214 reciprocates in the arrow direction by the forward and reverse rotations. Then, in the frame, a sensor S that detects the third position (solid line position) of the gripper unit 212, a sensor S _A that detects the first position (dotted line), and a second position (dotted line) are detected. The sensor S _B is installed. Furthermore, the gripper unit 2
12 is a lower gripper arm 217 as shown in detail in FIG.
The upper gripper arm 218 is supported by the shaft 219, and by rotating the eccentric cams 217a and 218a contacting the upper gripper arm 218 by the motor Me, the solid line position (holding position) and the two-dot chain line position (opening position) can be set. Rock. Further, the spring members 217b and 218b attached to the respective gripper arms are configured to constantly urge the gripper arms toward the eccentric cam and at the same time obtain a predetermined holding force.

The transport unit 213 will be described with reference to FIG. Two lower conveying rollers 222 are arranged in the axial direction on a lower roller shaft 222a supported by front and rear side plates (not shown) of the intermediate unit 210.
An upper conveying roller 221 is arranged on the upper roller shaft 221a on the upper side facing the second roller. Both ends of the upper roller shaft 221a are held by a swing arm 221b fitted to a shaft 221d supported by the side plate. Then, the swing arm 2
21b of the swing arm 221b.
An eccentric cam 223 that oscillates between a solid line position (holding position) and a two-dot broken line position (opening position) is installed on a shaft 223a that is rotated by a motor Mg. The outer diameters of the upper transport roller 221 and the lower transport roller 222 are equal, and they rotate at a constant speed in the arrow direction by driving the motor Mf.

Then, as shown in FIG.
The frame extending in the vertical direction of 0 has the bin tray B
_{1, B 2, B 3 ...} B 8, B 9, the sensor S ₁ to face the lowermost position of the _{B 10, S 2, S 3} ... S 8, S 9, Binsensa group S _N containing S ₁₀ is It is fixed. Then, each sensor S ₁ ...
S ₁₀ detects the sheet surface at the lowermost point 211b and the stack tray 220 of the intermediate tray 211. A sensor Se is disposed below the nip position of the roller pair 221 and 222 of the intermediate unit 210, and the stack tray 220
The paper surface of is detected. The sensor S _D is fixed to the frame of the stack device and detects the lower limit position of the stack tray 220. The sensor Sf is provided on the surface of the stack tray 220 near the intermediate unit 210 and detects the rear end of the sheet bundle to be transferred. Then, the CPU receives the signal of each sensor, controls the output of each motor, and further sorts the sorting device 10
0 and the image forming apparatus 300.

The operation of the apparatus based on the above configuration will be described with reference to the flowchart (FIG. 10) and other drawings.

(Step 1) The operator operates the image forming apparatus 30.
The original is set to 0, the number of sorts N and the like are set, and then the start key is pressed.

(Step 2, Step 3) As shown in FIG. 6, the intermediate unit 210 moves to a position corresponding to the lowermost bin tray B _10, and the stack tray 220 is lowered by the drive of the motor Mb until the lower limit sensor S _D detects it. To do.

(Step 4) The CPU recognizes the number n of usable bin trays (the number of bin trays located above the sheet surface of the stack tray 220 ) by the bin sensor group S _N detecting the sheet surface of the stack tray 220. For example, in the state of FIG. 6, the sensor for detecting the paper surface is S ₆
The number n of usable bin trays is the bin trays S _{1 to} S ₆
There are 6 stages.

(Steps 5 to 8) The CPU compares the number of sorts N at the time of initial setting with the number n of usable bin trays (Step 5), and if N ≦ n, sorts the N copies according to the set values (Step 6). , N> n, sorting of n copies is first started (Step 7).

The sorting operation is disclosed in Japanese Patent Laid-Open No. 63-262.
Since it is described in detail in Japanese Patent No. 373, a brief description will be given here. As shown in FIG. 5, the discharged sheet on which the image is formed by the image forming apparatus 300 is held between the roller / roller pair 101a and 101b of the first distribution device 101 which is on standby at a position corresponding to the discharge roller pair 313. Then, the first distribution device 101 is subsequently moved to the position of the second distribution device 105 waiting at the sheet insertion port of the predetermined bin tray. After that, the sheet is delivered to the second distribution device 105 by the rotation of the roller / roller pair 101a, 101b, and the roller / roller pair 105a, 105b of the second distribution device 105.
It is discharged to a predetermined bin tray via. The first
In the distribution device 105, the leading end of the sheet is the second distribution device 105.
When it is held by the roller / roller pair 105a, 105b, it is returned to the position of the paper discharge roller pair 313 of the image forming apparatus 300, and holds the next discharged sheet. Then, the second distribution device 105 stopped at the predetermined bin tray moves up or down one step, and waits for delivery of the next sheet conveyed by the first distribution device 101.

By repeating the above operation, the sheets are sequentially distributed to the bin trays. The alignment of the sheets discharged to each bin tray is as described above. Then, all the image-shaped sheets are aligned and stacked on each bin tray (Step 8).

(Step 9, 10) Above (Step 8)
At, a sort end signal is sent to the stack device 200.
The sensor S _A detects whether or not the gripper unit 212 of the intermediate unit 210 is in the first position (FIG. 7). If it is not in the first position, the sensor S _A moves until it is detected. Further, it is confirmed whether the lower gripper 217 and the upper gripper 218 are in the open state (FIG. 8), and when they are not in the open state, both grippers are swung to open. Further, the pair of transport rollers 221 and 222 of the transport unit 213
Check if is open, and if it is not open,
The upper transport roller 221 is swung to open.

(Step 11 ) In the aligned sheet bundle shown in FIG. 4, as shown in FIG. 11, after the reference rod 108 is returned to the standby position 108a, the alignment rod 115 is swung in the arrow direction by a predetermined amount (115c). ), The side end of the sheet bundle is moved to the stacking device 200.

(Step 12) The intermediate unit 210, which has been on standby at the position corresponding to the lowermost bin tray B _{10 in} (Step 3) above, is lifted by the drive of the motor Ma and is moved to the lowermost stage in the bin in which the sheets are stacked. Bin tray B _N
When the bin sensor S _N (S _{6 in} the case of the example in FIG. ₆ ) corresponding to is detected, it is stopped. Furthermore stack tray 220 is raised, the sensor S _A of the intermediate unit 210 is stopped when it is detected the paper.

(Step 13) As shown in FIG. 12, the gripper unit 212 moves by the motor Md and stops when it reaches the third position detected by the sensor S _C.
At this time, the tip corners of the sheet bundle S are inserted between the upper and lower grippers 217 and 218 which are in the open state, and the upper and lower grippers 217 and 218 move to the gripping state so that the tip corners are securely held. It Then, the gripper unit 212 is moved to the first position where the sensor S _A is located, so that the sheet bundle S is opened and the pair of upper and lower conveying rollers 22 are opened.
1 and 222 (FIG. 13). Then, the pair of grippers 217 and 218 are opened to open the sheet bundle, and then the pair of transport rollers 221 and 222 shift to the sandwiched state to sandwich the sheet bundle with a predetermined pressure. Then, the conveying roller pairs 221 and 222 are rotated in the arrow direction by the drive of the motor Mf, and the sheet bundle is transferred to the stack tray 220 (FIG. 14).

(Step 14 ) When the sensor S _f shown in FIG. 13 detects the rear end of the conveyed sheet bundle S, the sheet bundle S is stacked on the stack tray 220 (stacking completion detection).

[0038] (Step 15) When the (Step12) of the lowermost sheet is placed in the bin trays B _N was bin tray B ₁ represents, as (Step1
Go to 6), if not (Step 12)
The operations from (Step 15) to (Step 15) are repeated to sequentially convey and store the sheet bundle from the lower bin tray to the stack tray 220.

(Step 16) N in the above (Step 5)
If ≦ n, the operation is terminated as it is. Also (Ste
If N> n in p5) and the number of remaining copies N ′ exists, the process returns to (Step2), and (Step2) to (S2).
Repeat up to step 16).

(Other Embodiments) The sheet bundle prepared by the apparatus of the above-mentioned embodiment was a transfer and storage of an unstitched bundle which has not undergone binding such as gluing or staple binding. The binding means may be provided and the binding process may be performed on the sheet bundle.

Further, in (Step 13) of the above-described embodiment, the gripper unit holding the sheet bundle has only the first position, but the above-mentioned stop position for each sheet bundle conveyed is the first position described with reference to FIG. The position may be changed to the second position. With the above operation, the sheet bundle stored in the stack tray 220 is spatially divided for each bundle.

Further, an example in which the processing speed is improved when the sheet processing apparatus performs a plurality of sorts will be described.

The CPU sets the sort number N to at least 2.
Into two (N ₁ and N ₂ ), and first about the number of copies N ₁ (St
The operation after ep6) is performed, and when the operation reaches (Step9), the operation after (Step6) is simultaneously advanced for the number of copies N ₂ . In this way, while the sheet bundle initially loaded in the bin tray is being transferred to the stack tray 220, the sorting process after the remaining number of copies is performed and the processing time can be shortened. The values divided into N ₁ and N ₂ are the values most suitable for the processing speed of the device. At this time, the above-mentioned alignment on the bin tray is not performed.

Further, in (Step 3), the interval between the sensor S ₁ corresponding to the uppermost bin and each bin sensor S _N for detecting the paper surface of the stack tray 220 is a value determined at the time of designing, and sheets that can be stored in the interval. The number can be experimentally known. Therefore, by inputting the number of storable sheets corresponding to each of the intervals in advance to the CPU, the total number of sheets calculated based on the number of originals and the number of sorts set in (Step 1) is the number of storable sheets. If it exceeds, the operation may be prohibited or the operator may be warned.

In the above embodiment, the transfer of the sheet bundle placed on each bin tray to the stack tray is carried out in order from the lower sheet bundle. However, as described below, it may be appropriately selected depending on the situation whether the sheet bundle is sequentially transferred from the upper side or the sheet bundle is sequentially transferred from the lower side.

For example, as described above, the number of sheets that can be stored within the interval between the bin sensors S _N is input to the CPU in advance. Then, the total number of sheets N ₃ is calculated based on the number of originals set in (Step 1) and the number of sorts n. Here, in order to clarify the explanation, the stack device 20
0 is in the state shown in FIG. 6 and the set sorting number n is “4”, the lowermost bin tray B ₄ used in sorting and the corresponding sensor S ₄ and stack tray 22 are used.
Number of sheets N ₄ that can be housed between the sensor S ₆ for detecting the paper of 0 is recognized by the CPU, the N ₃ and N ₄
When the relation of N ₃ <n ₄ is satisfied, the bin trays B _{1 to} B ₄
The sheets sorted into B
₁ , B ₂ , B ₃ , B ₄ are taken out in this order, or B ₄ ,
It is selected whether B ₃ , B ₂ and B ₁ are taken out in this order. That is, the intermediate tray 210 starts to transfer the sheets from the side of the bin tray in which the last sheet of the sort is stored first. This selection is determined by the number of originals at the time of setting, and the sheet bundle is sequentially taken out from the bin tray in which all the sheets are stored, so that the waiting time of the apparatus is shortened and the processing time is shortened.

When the CPU determines that N ₃ > N ₄ , the selection is not performed and the sheet bundle is taken out sequentially from the lower bin tray as in the above embodiment.

In the above embodiment, the intermediate tray was used to transfer the sheets from the bin tray to the stack tray, but the present invention is not limited to the above construction. For example, the intermediate unit 210 may have a configuration in which only the transport roller unit 213 (which may be a gripper) that transports the sheets in the bin tray to the front side and the stack tray 220 is disposed downstream thereof. The operation of each member is the same as that of the above-described embodiment, and as shown in FIG. 18, which is a top view of FIG. 17, an intermediate unit that raises and lowers the sheets stored in each bin tray to a position facing each bin tray. The stack tray 220, which is transported by the transport roller unit 213 of 210, and whose paper surface is controlled to a position corresponding to the transport roller unit 213.
To be stored in.

[0049]

The sheet post-processing apparatus according to the present invention is configured as described above, and the transport unit transfers the sheet bundle to the stack tray in order from the lower bin tray on which the sheets are placed. It is possible to transfer all sheets to the stack tray even if the sheet storage capacity of is increased.

Further, by providing a means for detecting the paper surface position at the lowermost position of the stack tray of the above apparatus and a means for recognizing the number of bin trays located above the paper surface, the stacking of sheets is advanced. Even if the paper surface position of the tray rises, the bin tray above it can continue to store sheets.

[Brief description of drawings]

FIG. 1 is a main sectional view of a device of the present invention.

FIG. 2 is a perspective view illustrating a bin unit.

FIG. 3 is a top view of FIG.

FIG. 4 is a top view of FIG.

FIG. 5 is a main sectional view of a sorting device and a stacking device.

FIG. 6 is a main sectional view of a sorting device and a stacking device.

FIG. 7 is a top view illustrating a stack device.

FIG. 8 is a front view of a grip for explaining the stack device.

FIG. 9 is a front view of a transport unit illustrating a stack device.

FIG. 10 is a flowchart of the operation.

FIG. 11 is a top view illustrating the operation.

FIG. 12 is an enlarged view for explaining the operation.

FIG. 13 is a front view illustrating the operation.

FIG. 14 is a front view illustrating the operation.

FIG. 15 is a view of a conventional device.

FIG. 16 is a front view of a conventional device.

FIG. 17 is a front view of another embodiment.

FIG. 18 is a top view of another embodiment.

[Explanation of symbols]

100 Sorting device 108 Reference rod 115 Alignment rod 200 Stacking device 210 Intermediate unit 211 Intermediate tray 212 Gripper device 213 Conveying roller 220 Stacking tray 300 Image forming device B ₁ bin tray

Claims (5)

[Claims] 1. A plurality of sheet receiving trays fixedly installed above and below which can store sheets, a sheet discharging means for discharging sheets into the receiving trays, and a movable up and down position facing each of the receiving trays. A sheet post-processing apparatus comprising: a conveying unit that conveys a sheet; a sheet stacking tray that receives and stacks the conveyed sheet; and an elevating unit that elevates and lowers the paper surface of the sheet stacking tray to a position corresponding to the conveying unit, A sheet post-processing apparatus, wherein the transport unit sequentially transports sheets from a lower tray to a sheet stacking tray. 2. A sheet surface position detecting means for detecting the sheet surface of the sheet stacking tray when the sheet stacking tray is at the lowermost position, and a recognizing means for recognizing the number of trays existing above the sheet surface. The sheet post-processing apparatus according to claim 1, characterized in that. 3. The sheet post-processing apparatus according to claim 1, wherein the sheet is stored using a tray existing above the sheet surface position detected by the sheet surface position detecting means. 4. A plurality of upper and lower fixed sheet trays capable of accommodating sheets, sheet ejection means for ejecting sheets to the trays, and a vertically movable position facing the respective trays. A conveyance unit that conveys sheets, a sheet stacking tray that receives and stacks the conveyed sheets, an elevating unit that raises and lowers the sheet surface of the sheet stacking tray to a position corresponding to the conveyance unit, and the sheet stacking tray is at the lowest position. In a sheet post-processing apparatus including a paper surface position detection means for detecting a paper surface position at a certain time, a recognition means for recognizing the number of trays existing above the paper surface, and a control unit for controlling the respective means, When the distance between the paper surface position detected by the paper surface position detecting means and the lowermost tray for storing the sheets above the paper surface position can accommodate all the sheets stored in each of the trays. It is characterized in that it is selectively determined in accordance with a sheet processing mode whether the transport unit sequentially transports sheets from the lower tray to the sheet stack tray or sequentially transports sheets from the upper tray to the sheet stack tray. Sheet post-processing device. 5. When the distance between the paper surface position detected by the paper surface position detecting means and the lowermost tray for storing sheets above the paper surface position exceeds the total sheets stored in each of the trays, 5. The sheet post-processing apparatus according to claim 4, wherein the transport unit sequentially transports the sheets from the lower tray to the sheet stack tray.