JPH0977348A - Sheet handling device and image forming device provided with it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet handling device which easily stack sheets folded by a sheet folding device on a bin. SOLUTION: Sheets discharged by a pair of discharging rollers 8g are stacked on a plurality of bins B11 to B16 . When the highest bin is freely moved between conventional unfolding sheet receiving position (H) and a position one step lower than the position and receives a folded sheet, the bin B11 is moved to the position one step lower than the sheet receiving position, thereby forming wide space over the bin and easily stacking folded sheets for the bin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, for example, stacks sheets that are sequentially discharged one by one from an image forming apparatus after being distributed to a plurality of stacking means, and then selectively subjected to post-processing such as binding processing. It relates to an aftertreatment device.

[0002]

2. Description of the Related Art Conventionally, a sheet post-processing apparatus is disclosed in Japanese Patent Laid-Open No.
The devices shown in Japanese Patent Laid-Open Nos. 138291, 4-156392, and 4-164692 are known.

In Japanese Laid-Open Patent Publication No. 4-138291 (first publication), as shown in FIG. 31, a sorter 302 that sorts sheets discharged from the image forming apparatus 301 into a plurality of bins 302b, and a sheet sorted into each bin. And a stapler 302d that binds the image forming apparatus 301 and the sorter 3 together.
02, a sheet stock path 305 installed between the sheet stock path 305 and the image forming apparatus 301 to the sorter 302, and a discharging means 306 for discharging the sheet from the bin 302b to the stock section 305, and a discharging means for each bin. The sheet is sorted into each bin of the sorter and stapled, and then discharged to the stock section.

Further, in Japanese Patent Laid-Open No. 4-156392 (second publication), as shown in FIG. 32, a sorting unit 307 for distributing and storing sheets discharged from an image forming apparatus.
And a conveying path 309 provided between the discharging section 308 and the sorting section 307 of the image forming apparatus and a stapling apparatus 310 for binding the sheet bundle stored in the sorting section, and the conveying path 30.
9 and a stack portion 311 that accommodates the bound sheet bundle.

In both the above-mentioned first and second publications, a stack of sheets is conveyed from the sorting section to another stack section so that the processing of more copies than the number of bins can be performed.

In recent years, image forming apparatuses have been required to have enhanced functions capable of coping with the diversification of purposes of use. For example, the same series size (A3 and A4, or B4 and B
In order to process a document in which 5) is mixed, a folding device that folds large-size paper (A3, B4) according to the size of small-size paper (A4, B5) is known. This folding device is disclosed in JP-A-61-232372 and JP-A-62-590.
Since it is described in the specification No. 02, detailed description will be omitted here.

[0007]

In order to use the above-mentioned sheet folding apparatus in combination with the above-mentioned conventional sheet post-processing apparatus, there are the following problems.

In the sheet post-processing apparatus, many bins are desired to be arranged in order to improve the storability of the sheet bundle. However, the increase in the number of bins narrows the tray interval due to the determined device size, and makes it difficult to stack a large number of folded sheets folded by the sheet folding device.

Further, as shown in FIG. 33, when the next sheet S is discharged in a state where the folded sheets S are stacked on the tray B, the folded portion of the folded sheet S expands due to the reaction force, and thus the discharged sheet. There is a risk that the leading edge of the sheet S may get into the folded portion and the sheet S may be jammed.

It is an object of the present invention to provide a sheet post-processing device which facilitates stacking of folded sheets folded by the folding device on a bin.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a stacking unit arranged in a plurality of stages for storing sheets to be discharged, and a stacking unit Sheet discharging means for discharging the sheet at the sheet receiving position, moving means for moving the stacking means to the sheet receiving position, and bending the discharged sheet in a direction perpendicular to the sheet conveying direction so that the sheet has a desired size. In the sheet post-processing apparatus, the stacking means for stacking the folded sheets is the uppermost stacking means, and the stacking means at the sheet receiving position is for stacking sheet bundles not including folded sheets. It is movable to the unfolded sheet receiving position for storing and the folded sheet receiving position for storing a sheet bundle including the folded sheets, and Sheet receiving position without folding is characterized in that in the position lowered to the folded without sheet receiving position.

The stacking means for stacking the folded sheets is the uppermost stacking means, and the folding sheet receiving position of the stacking means is such that the extension line in the sheet discharging direction by the sheet discharging means is above the stacking means. It is characterized in that it descends with respect to the unfolded sheet receiving position so as to get over the sheets stacked on the sheet.

Further, the lowering amount of the stacking unit to the folded sheet receiving position is increased in proportion to the sheet stacking amount on the stacking unit.

[Operation] Based on the above construction, the sheet discharged by the sheet discharging means is discharged onto the stacking means moved to the sheet receiving position by the moving means. When accommodating a sheet bundle that does not include folded sheets, the stacking means receives the sheets at the unfolded sheet receiving position, and when accommodating the folded sheets, the stacking means does not fold from the unfolded sheet receiving position. It descends to the sheet receiving position and receives and stores folded sheets. As a result, a thick folded sheet can be stored on the stacking unit.

Further, even if the folded sheet stacked on the stacking means swells due to its restoring force, the next sheet to be discharged will pass over the stacked sheet and be discharged so that the folded sheet is received. The position is in the lowered position. As a result, when the sheets are discharged to the stacking unit that stacks the folded sheets, the leading edge of the sheets does not catch on the stacked sheets and jam.

Further, when the folded sheets are stacked, the descending amount of the stacking unit to the sheet receiving position increases in proportion to the stacking amount of the sheets stacked on the stacking unit. As a result, the top surface of the uppermost sheet stacked on the stacking unit is always positioned below the extension line of the sheet discharging unit in the sheet discharging direction even if the sheet stacking amount increases, and thus the sheet discharging unit The stackability of sheets is improved.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an electrophotographic copying machine (image forming apparatus) 200 as a sheet output device.

The electrophotographic copying machine 200 includes a copying machine main body 20.
1 and an automatic document feeder 2 arranged at the top of the copying machine main body
02, and a sheet post-processing device 203 arranged on the side of the copying machine main body 201 where the sheet S is discharged. In addition, the sheet post-processing device 203 includes a folding device 204.
And the stapling / stacking device 205 and a control device 300 for controlling the operation of each means.

The document table 20 of the automatic document feeder 202
6 are separated in order from the bottom,
Pass 20 on the platen glass 208 of the copying machine body 201
After being read, the sheet is fed by the optical system 210 of the copying machine main body 201, and after the reading is finished, the sheet is ejected from the platen glass 207 via the path 211 to the uppermost surface on the document placing table 205. The sheet S is fed from the deck 212, an image is formed by the image forming unit 213, and is fixed by the fixing unit 214. The sheet S is selectively subjected to the folding action of the folding device 204, and the sheet inlet of the stapling / stacking device 205. Two
It is designed to be transported to 15.

Here, the image forming process of the copying machine 200, which is the main body of the present invention, is well known and will not be described here.

As shown in FIGS. 1 and 2, the stapling / stacking device 205 has bin modules B ₁ and B ₂ which are vertically divided into _two , and each bin module has a plurality of bins (stacking means) B. _{11 to} B _1n , B _{21 to} B _2n (n =
6). Each bin module can individually move the bin intervals and bin positions by rotating independent lead cams (moving means) 16 to move each bin to the sheet receiving position or the sheet bundle discharging position.

As will be described later, the uppermost bins (B ₁₁ , B ₂₁ ) of the bin modules B ₁ , B ₂ are arranged so that they can be moved between positions at least one step lower than the sheet receiving position, as will be described later. Is configured.

At the sheet carry-in port 215, the first upward
It is driven by a solenoid SL3 (not shown) that switches between the transport path 1 and the second transport path 2 in the downward direction. The deflector 3 determines the traveling direction of the sheet S. Further, the first conveying path 1, the deflector 4 driven by a solenoid SL4 not shown, branches into discharge path 6 and the upper module B ₁ f of path 7 to the non-sort tray 5.

On the other hand, the second transport path 2 is a path to the lower module B as it is. Therefore, each roller pair 8a
8p, 8b, 8b,
8c, the upper module is conveyed by a pair of rollers 8a, 8b, 8d-8g, and the lower module is conveyed by a pair of rollers 8a, 8h-8p.

The sheet is discharged to the bin of the upper module B ₁ by a discharge roller (sheet discharging means) 8g, and the sheet is discharged to the bin of the lower module B ₂ by a discharge roller (sheet discharging means) 8p. .

The stapling / staff device 205 is also provided.
Is 1 by the sandwiched path 1 and the lower module B ₂ F paths 2 to the upper module B ₁ space, has a grip / stapling unit 9, first-out gripper 10 bundles on each bottle 2 After the bundle is transported to the right and selectively stabilized by the stapler 11, the leading end of the bundle is held by the transport gripper 12 and further transported to the right. Similarly, in the space between the path to the upper module B ₁ and the path to the lower module B ₂ , the stack unit 13 stands by below the grip / staple unit 9, and the transport gripper 12
Store the bundle conveyed in.

Further, as shown in FIG. 2, the right end of the stapler 11 and the left end of the stack unit 13 are substantially overlapped in the left-right direction (region of width l _{15 in} FIG. 2).

After the bins B _{11 to} B ₁₆ of the upper module B ₁ are filled with the sheet bundle, the grip / staple unit 9 is moved to the position shown by the broken line in FIGS. While the bundle is being taken out, the sheets are conveyed to the bins B _{21 to} B ₂₆ of the lower module, and after the bundle is taken out from the bins B _{11 to} B ₁₆ , the bin B of the lower module B _{2 is} also removed.
After the completion of transporting 4 to _{21 to} B ₂₆ , this time the bundle is taken out from the lower module at the position indicated by the solid line in FIGS. By repeating this operation, copying can be continued continuously until the stack unit becomes full.

Next, the folding device (folding means) 204 will be described with reference to FIGS. 11 to 13. Here, the folding device 204 can operate according to three modes.

The first through-pass mode is a 0 operation in which the sheet 251 does not pass a folding operation, and in this through-pass mode, the sheet 251 carried in by the pair of inlet rollers 227 and 228 is the same as the inlet deflector 2.
The sheet post-processing device 203 is guided to the sheet path 230 by the operation of 29, and is discharged by the pair of discharge rollers 231 and 232.
Sent to

The second C-folding mode is LGL sheet 2
The sheet 251 is bent in two to form an LTR (longitudinal) size, and the sheet 251 guided to the entrance deflector 229 from the entrance roller pair 227, 228 is introduced into the folding path 236 by the operation of the deflector 234.

Thus, as shown in FIG. 12A, when the leading edge of the sheet 251 contacts the stopper 243, the loop 25 formed in the central portion on the downstream side of the sheet.
0 is gripped in the nip between the folding rollers 238 and 239, and the loop 250 formed in the central portion on the downstream side of the sheet 251 is gripped in the nip between the folding rollers 238 and 239, as shown in FIG. As shown in b), a fold line 251A is formed in the central portion on the downstream side of the sheet to form a half-folded sheet. Thus, the half-folded sheet 251 then passes through the paper path 240 and is delivered by the pair of paper ejection rollers 231 and 232.

The third Z-folding mode is a mode in which the sheet 251 is folded in half at one end and the other half is folded back to the opposite side. First, the sheet 251 is fed from the pair of inlet rollers 227 and 228 by the inlet deflector 229. Pass 2
Sent to 33. Further, the sheet 251 is delayed by the deflector 234 to the path 242, and the leading end of the sheet 251 contacts the stopper 245.

Thus, similar to the above-mentioned two-fold mode,
A loop is formed in a portion of about 1/4 from the front end of the sheet 251, and the loop is formed by the folding roller pair 23.
It is held in the nip with 8,237 and the first fold 2
51B is formed into a half-folded sheet (see FIG. 13).
(A).

Then, the sheet 25 folded as described above.
1 is introduced into the folding path 236, and when the fold line 251B of the half-folded sheet 251 is abutted against the stopper 244, a loop is formed in the center of the half-folded sheet 251 in the same manner as described above. The loop is gripped in the nip between the pair of folding rollers 238 and 2389 to form the second fold line 251C (FIG. 1).
3 (b)). In this way, the Z-folded sheet folded back and forth passes through the path 240 and the pair of discharge rollers 231 and 23.
2 is sent.

As described above, the discharged sheet S is selectively C-folded or Z-folded by the folding device 204,
It is conveyed to the bin modules B ₁ and B ₂ .

Next, the bin modules B ₁ and B ₂ will be described.

FIG. 3 is a perspective view of the bin module.
Hereinafter will be described bin module B _1, but the same configuration applies to B _2.

The bin module B ₁ is mainly composed of the bins B ₁₁ to B.
_1n and two reference rods 14a and 14b, an alignment wall 15, lead cams 16a to 16c for elevating and lowering the bin, and a drive unit for these. The reference rods 14a and 14b are
It is a member that determines a reference line for post-processing such as stapling for a sheet discharged onto a bin, and is normally set to be slightly retracted from the position of the end portion when the sheet is discharged. The aligning wall 15 moves the sheets discharged onto the bin one by one in the direction perpendicular to the sheet conveying direction (the direction of arrow A in the figure), and the opposite ends of the aligning wall 15 are aligned with the reference bar 14.
Align with a and 14b.

FIG. 4 is a top view of the bin module. The lead cams 16a, 16b and 16c are shown in FIGS.
As shown in FIG. 1, one bottle is arranged on the front side of the bottle and two bottles are arranged on the rear side thereof, and a spiral lead cam is provided on the outer circumference. Rollers Ba, Bb, Bc protruding from the bin are engaged with the lead cam, and the bin is raised and lowered by a predetermined pitch each time each lead cam makes one rotation in synchronization.

As shown in FIG. 4, the bin is provided with a notch Bd corresponding to the reference rod and a hole Be corresponding to the matching wall, and a notch Bf for a gripper, which will be described later, and a bin standing. Notch Bg for drive mechanism and notch B required for operation
h is formed.

FIG. 5 is a front view of the bin module.

As shown in FIG. 5, the bins are arranged in parallel with each other at an angle to the horizontal. On the other hand, all the bin roller portions Ba, Bb, and Bc are configured to have the same height when the bin is inclined. That is, the position of the bin roller Bb near the right side of the bin is near the reference plane of the bin, while the position of the bin roller Bc near the left side of the bin is considerably below the reference plane of the bin,
The bin roller Bc is connected to the bin by a V-shaped fixed arm.

As a result, even when the adjacent bins such as B ₁₅ and B ₁₆ shown in FIG. 5 approach each other, the interference of the arm portions can be avoided. Further, since the bin roller portions Ba, Bb, Bc are all at the same height, the positions of the lead cams 16a to 16c in the height direction can be set at the same height, and the overall size can be reduced. That is, as compared with the case where the rollers Ba, Bb, and Bc are provided in the vicinity of the thick portion of each bottle as shown in FIG. 5B, the size l ₁₆ minutes shown in FIG. .

Next, the bin interval will be described with reference to FIGS. 5 and 6.

FIG. 5A shows the upper module B _{1 in the} case where no folded sheets are stacked. In the figure, the second bin B ₁₂ from the top is a pair of discharge rollers (sheet discharging means) 8g. At the corresponding sheet receiving position H, the sheet discharged by the pair of discharging rollers 8g is received.

As shown in FIG. 6, the bin groups B ₁₁ to B ₁₆ are configured such that the uppermost bin B ₁₁ can move to a position I which is lowered by one step with respect to the sheet receiving position H, and is folded. In the folding mode including the sheet, the lowered position I
In, the sheets are stored only in the uppermost bin B ₁₁ .

On the other hand, the fourth bin B ₁₄ from the top is shown in FIG.
As shown in (a), at the bundle discharge position, when the sheet discharge to the bin is completed, the bin is sequentially shifted to this position,
Eject bundles from each bottle. In FIG. 5A, the bin B
₁₁ .about.B large bins interval l ₁₇ until _15, small and only l ₁₈ between the B _15, B _16, but between the bottle varies depending on the situation.
In FIG. 7, the bin B ₁₆ is at the sheet receiving position, and the bin is shifted to the uppermost position. At this time, the bin interval is from B ₁₁ to
Until B ₁₅ small in l _18, larger in l ₁₇ only between B _15, B _16.

Further, in FIG. 6, the bin B ₁₁ is in the bundle discharging position, and the bin is shifted to the lowest position. At this time, the bin interval is large at l ₁₇ only between B ₁₁ and B ₁₂ , and the other is l _18. And small. That is, the interval between the bottles in the sheet receiving position and the bottle thereon is greater about l _17, also above and below the bin and the bin in the bundle discharging position should have as large as l ₁₇ intervals. In FIG. 5, B ₁₁ and B ₁₂ , B ₁₃ and B
₁₄ , B ₁₄ and B ₁₅ . In FIG. 5, the distance between B ₁₂ and B ₁₃ is also large, but this may be functionally as small as about ₁₈ , and the size of the distance is determined by the relationship between the upper half space of the stapler 11 and the bin distance. It

On the other hand, in the case of the lower bin module B ₂ ,
As can be seen from FIGS. 1 and 2, the sheet receiving position and the bundle discharging position are upside down from those of the upper module.
Therefore, in the same way, in FIG. 2, the distance between the bin B _{24 at the} sheet receiving position and the upper bin B ₂₃ is l.
Greater to about _17, although the interval between the bin B ₂₂ in the bundle discharging position and the upper and lower bin B _21, B ₂₃ needs large as l _17, between B ₂₄ and B ₂₅ are not large enough l ₁₇ May be.

However, by increasing the distance between B ₂₄ and B ₂₅ to about _{17 as} well, although the sheet receiving position and the bundle discharging position are reversed, the upper and lower modules have the same interval structure. That is, the pitch of the lead cams that determine the bin interval may be the same, and there is an advantage that the upper and lower lead cams are commonly used. Also, the fact that the sheet receiving position and the stack discharging position are reversed in the upper and lower modules
There is another advantage that the grip / staple unit 9 and the stack unit 13 can be shared when the sheet is taken out.

Lower module B₂ Of the top bin B
_{twenty one}Also, upper module B₁ Of the top bin B₁₁ As with
Unfolded sheet when storing sheets, including sheets
Lower than the seat receiving position H for storing
It is configured to be movable to the lowered position I.

Next, driving of the bin shift will be described (FIGS. 4 to 6).

The bin shift motor M1 is a motor pulley 1
8, the belt 19 and the lead cam pulleys 20a to 20c transmit drive synchronously to the lead cams 16a to 16c, rotate the motor forward and reverse, and rotate the lead cam once, thereby raising and lowering the bin by the cam pitch. Lead cam 1
Each of the shafts 6a to 16c is rotatably supported by a bearing, and the pulley 20a attached to one side of the shafts 6a to 16c.
Drive is transmitted from ~ 20c. Bin shift motor M1
Has an encoder 21 at a position opposite to the pulley 18, and the sensor S ₁ detects one rotation.

Further, each bin module B ₁ , B ₂ has
There is a home position detection sensor S ₂ ((not shown)), which detects that the respective uppermost bins B _{11 to} B ₂₁ are at the respective sheet receiving positions H. Further, each bin module B ₁ , B ₂ has a penetration sensor S3 (FIG. 2) for detecting the sheet on the bin, and detects the presence or absence of the sheet on the bin to determine the timing of switching the modules. There is.

Next, the alignment wall 1 for aligning the sheets on the bin
The drive configuration of No. 5 will be described (FIGS. 9 and 10). FIG.
Is a top view of the matching wall drive unit, and FIG. 10 is a front view.

A shaft 22 is caulked on the alignment wall 15, and the caulking shaft 22 is stopped by penetrating a U-shaped support plate 23. On the other hand, the U-shaped support plate 23
A compression spring 24 is installed in the inside of the plate while being slightly biased in the compression direction. One side of the compression spring 24 is abutted against the inner wall of the plate 23 and the other side is abutted against a stopper 25 provided on the caulking shaft. The caulking shaft 22 and the matching wall 15 are urged downward in FIG. 9 by the force of the compression spring.

The lower side of the U-shaped support plate 23 is fixed to the moving side of the accuride 27 via a slide plate 26, and the fixed side of the accuride 27 is an accuride rail plate 28 extending in the sliding direction of the alignment wall. It is fixed to. On the accurride rail plate 28, caulking shafts 29 and 30 stand on the front side and the back side, and the pulley gear 3 is attached to each of them.
1. A pulley 32 is rotatably attached. A timing belt 33 is passed between the pulleys 31 and 32,
The slide plate 26 is fixed to the belt 33. on the other hand,
The motor gear 34 of the matching wall drive motor M2 is the pulley gear 3
The driving force is transmitted by engaging with the first gear portion.

The home position of the matching wall 15 is
It is detected by the sensor S4. U-shaped support plate 23
A slide member 35 is attached to the upper part of the above and is guided by engaging with a concave portion of a fixed rail 36. In FIG. 10, the drive is applied from below the alignment wall 15 and the upper part is guided by the rail, but it may be upside down. Further, the structure of the matching wall and the way of driving may be reversed between the upper module and the lower module.

Next, the drive structure of the bin standing portion forming the alignment surface in the transport direction on the bin will be described (FIGS. 14 and 15).

This is to move the bin standing when the sheet bundle stacked on the bin is conveyed from the bin in the bin standing direction for post-processing and stacking. FIG.
4 is a top view and FIG. 15 is a front view.

The bin B includes a sheet stacking unit Bi and a aligning unit B.
The rotating shaft on the aligning portion Bj side is fitted into the rotating hole on the stacking portion Bi side to form the aligning portion B.
j is rotatable. The rotation angle of the matching portion Bj is
As shown in FIG. 15, the aligning surface, which stands at a right angle to the fixed loading surface, can be rotated at about 90 ° until the loading surface is substantially flush with the loading surface. Normally, a spring or the like is urged so that the alignment surface is perpendicular to the loading surface (solid line in FIG. 15). This spring has a strength such that the aligning portion Bj does not fall down even with the weight of the sheet bundle on the bin. A drive arm 45 is attached to the back side of the matching portion Bj. A pin 45 is attached to the tip of the drive arm.
a is set up.

The bin stand-up drive solenoid SL1 has a base 4
6 is supported on. A link 47 is rotatably supported on the base 46, and one end of an arm 48 is engaged with a pin 47a on the link. The other end of the arm 48 is attached to the solenoid SL1 and the solenoid 47 operates to move the link 47 from the solid line portion to the two-dot chain line portion. A pin contact member 47b is attached to the tip of the link 47, but in a normal state, the pin 47b and the pin 45a are separated from each other, and do not interfere with the lifting operation of the bin B. When sheets are discharged onto the bin and the sheet bundle in the bin is post-processed and stacked, the corresponding bin is
Shifting to position 5, the solenoid SLl is operated. The pin contact member 47b contacts the pin 45a, and the link 47 is further rotated to move the alignment portion Bj to the position of the chain double-dashed line in FIG. Solenoid SLl is O
When FF is performed, the link 47 returns to the original solid line position by the action of the spring 49, and correspondingly, the aligning portion Bj also returns to the position orthogonal to the loading surface.

Next, the grip / staple unit 9 will be described (FIGS. 16 and 17).

FIG. 16 is a top view of the grip / staple unit 9, and FIG. 17 is a front view.

The overall structure of the grip / stapling unit 9 is such that between the unit front side plate 50 and the unit rear side plate 51,
It has a frame body that passes the guide stays 52, 53 and the right stay 54, and four elevating rollers 55 are crimped on each of the left and right sides of the guide stays, two in total. On the inner side of the lower guide stay 53, a member 53a that guides when the sheet bundle is conveyed is attached.

The four rollers are guided in two rails fixed to the main body side and are integrally cut by the rail 56, and a pinion gear provided at both ends of a shaft 57 penetrating in the lateral direction of the frame. 58 meshes with the lifting gear M
The drive from 4 is transmitted, and the entire frame can be moved up and down.

Inside the frame of the grip / stapling unit 9, three moving bodies including a first-out clipper 10, a stapler 11 and a transport gripper 12 are arranged. The first-out gripper 10 is configured to be movable in the direction of arrow D in FIG. 16, grips the vicinity of the right end of the sheet bundle S on the bin on the front reference side, and pulls out the sheet bundle to the right. Distance from the right end of the first-out clipper 10 to the leading end of the sheet bundle S
₄ is set to be slightly longer than the distance l ₅ from the left end of the stapler 11 to the leading end of the sheet bundle S when the pulling out is completed.

The stapler 11 can be moved in the direction of arrow E in the figure, and can be moved to the front or rear evacuation position where it does not overlap with the sheet width, or any position on the leading end of the sheet bundle.

The transport gripper 12 is movable in the direction of arrow F in FIG. 16, and is also movable in the direction of arrow G in the figure including the entire front and rear side plates 59, 60. In the direction of arrow F, depending on the size of the sheet bundle, the sheet is gripped at a substantially central position of the sheet width, conveyed in the direction of arrow G, and the sheet bundle is completely pulled out from the bin and conveyed to the stacker described later.

The movement of the transport gripper 12 in the direction of arrow F is
In addition to moving according to size as described above, it is also used for sorting on the stacker. That is, when the bundle is conveyed to the stacker, the conveyance amount in the arrow G direction depends on the sheet bundle size, but by changing the conveyance amount in the F direction, sheet bundles of the same size can be sorted or different jobs can be sorted. You can do it.

The depth dimension l ₆ of the transport gripper 12 is set so that the leading edge of the sheet bundle S can be held even when the stapler 11 is operating with respect to the sheet bundle S. Hereinafter, the moving bodies 10, 11, 12 in the grip / staple unit 9 will be described in detail.

First, the grip portion for holding the bundle will be described. This is a common structure for the first-out gripper 10 and the transport gripper 12 (FIG. 18).

The side plates 62, 62 include three shafts 63, 6
4,65 are supported. The upper gripper 6 is attached to the shaft 65.
6 and a lower gripper 67 are provided, and by rotating the lower gripper cam 68 fixed to the shaft 63 and the upper gripper cam 69 fixed to the shaft 64 in the arrow directions, the arrow H and the arrow I are respectively moved. Swing is repeated (solid line and broken line).

Further, the spring member 70 urges the cam portion 67a of the lower gripper 67 to the lower gripper cam 68, and the spring member 71 urges the cam portion 66a of the upper gripper 66 to the upper gripper cam 69 so as to move the upper gripper to the upper gripper. The contact pressure of the lower gripper is controlled to be substantially constant. The cams of the upper / lower grippers are driven by motors M5 (holding the first-out gripper) and M6 (holding the transport gripper) (not shown).

The first-out gripper 10 and the transport gripper 12 have the same basic structure as described above,
The conditions such as the clamping pressure, the width of the gripper, the maximum opening amount, etc. may be optimally set according to the respective usage conditions. For example, in the case of the present embodiment, the first-out gripper holds down the upper width of the space small, but since it clamps only on the reference side, the clamping pressure is set high to prevent misalignment, and the opening amount also enters between the bins. The conveyance gripper can clamp the sheet bundle center while holding down the sheet bundle, so that the pressure can be set low. In addition, it can be generally set according to the curl amount of the sheet, the basis weight, the presence or absence of folding, the number of sheets, and the like.

Next, the drive structure of the first-out gripper 10 will be described (FIGS. 19 and 20). FIG. 19 is a top view of the first-out gripper 10, and FIG. 20 is a front view.

A roller 72 having a groove is crimped on the front side surface of the advance gripper 10, and the roller 72 is engaged with an elongated hole 50a provided in a unit front side plate 50 of the grip / staple unit. The slot 50a is formed substantially horizontally on the side close to the stapler, that is, on the right side of FIG. 20, but the slot 50a on the left side of FIG. 20 is a slot having an angle according to the inclination of the bottle. Has become. The tip ends of the shafts of the two rollers are connected by a connecting sheet metal 73, and a pin member 74 is attached to the sheet metal.

On the other hand, on the front side of the unit front side plate 50,
A first-out motor M7 is attached, and a swing arm 76 is fixed to the tip of the drive shaft. A long hole 76a is formed at the other end of the swing arm, and the tip of the pin member 74 is engaged with the long hole. By the drive of the advance motor M7, the swing arm 76 reciprocates between the solid line position and the chain double-dashed line position in FIGS. As a result, the first-out gripper 10 grabs the sheet bundle along the elongated hole of the unit front side plate 50 at the inclined position, conveys the sheet bundle to the horizontal position, separates the sheet bundle at the horizontal position, and performs a movement to change to the inclined position again. .

Next, the drive structure of the transport gripper 12 will be described (FIGS. 21 and 22). FIG. 21 shows the transport gripper 12
22 is a front sectional view.

First, driving of the transport gripper 12 in the sheet bundle transport direction, which is the left-right direction in FIGS. 21 and 22, will be described.

The transport gripper 12 has a 2
It is supported by the shafts 77 and 78 of the book. One of the axes 77,
It is composed of a ball screw, and the other 78 is composed of a normal shaft. Both ends of the shaft 77 are rotatably supported between the front and rear side plates (the front side plate is omitted; the rear side plate 60), and the shaft 78 is supported.
Both ends of are completely fixed. A guide roller 79 is caulked on each side plate, and the roller 79 can move in the left-right direction along an elongated hole 51 a formed in the unit side plate 51.

The transport gripper left-right movement motor M8 is attached to the unit side plate 51, and the motor pulley 80,
The drive is transmitted to the through shaft 83 via the belt 81 and the pulley 82. On the through shaft 83, a drive pulley 84 is
Driven pulleys 8 that are attached one by one in the back and face each other
A belt 86 is stretched between the belt 5 and the belt 5. By fixing a part of the belt on the rear side plate 60 by the regulation member 87, the drive of the motor M8 is transmitted to the transport gripper 12 and the lateral movement is enabled.

Next, driving in the vertical direction of FIG. 21, that is, in the direction orthogonal to the sheet bundle conveyance will be described.

On the rear side plate 60, a transport gripper forward / backward moving motor M9 is attached via a base 88. The motor M9 via the motor pulley 89, the belt 90, and the pulley 91.
Is transmitted to the ball screw shaft 77. A similar screw is also threaded on the portion of the transport gripper 12 that engages with the ball screw shaft 77, so that the transport gripper can be moved forward and backward by rotating the ball screw shaft.

The position of the transport gripper 12 is determined by detecting the home position and the rotation amount of the motor. In the lateral direction of the transport gripper 12, the home position sensor S7 detects the protrusion 87a above the regulating member 87, and the sensor S8 that reads the encoder 92 of the motor M8.
Detects the amount of movement and stops at a predetermined position. on the other hand,
Even in the reverse direction, the home position sensor S9 detects a part of the transport gripper, the sensor S10 that reads the encoder 93 of the motor M9 detects the amount of movement, and stops at a predetermined position.

On the other hand, when the transport gripper 12 moves back and forth, the home position detection sensor S9 detects a part of the transport gripper 12, and the sensor S10 that reads the encoder 93 of the motor M9 detects the amount of movement. Stop.

Based on the above configuration, the operation of each component will be described below. First, the basic operation of the device will be described.

First, an original is set on the original placing table 105 of the automatic original feeder 202 provided in the copying machine main body 201 (FIG. 1), and a predetermined mode condition is input by an operation unit (not shown) to start. The key is pressed. Each unit of the sheet post-processing device 203 is controlled to be in a standby state in response to the start key pressing signal. Hereinafter, description will be given separately for each mode condition.

(A) Non-sort mode In FIG. 2, the deflector 3 is positioned in the direction of the solid line and the deflector 4 is positioned in the direction of the broken line, and the roller pair 8a existing from the first transport path 1 to the transport path 6 is present. 8b, 8c
The motor M14 is controlled so as to rotate (see FIG. 2).
3). Of course, the roller pair in the upper part of the folding device 204 is also
The sheet is receivable by a folding motor M17 (not shown), and the sheet can be received.

However, the standby operation may be performed after the copying operation described below and before the sheet is discharged from the copying machine main body 201. When the sheet post-processing apparatus is in the standby state, the original 206 shown in FIG.
7, the copying machine main body 201 enters the copying operation.

The first sheet that has undergone image formation processing in the copying machine main body 201 and is discharged passes through the upper path of the folding device 204 and enters the stapling / stacking device 205 from the carry-in port 215. The sheet is deflected vertically upward by the deflector 3, is conveyed vertically upward on the right side of the deflector 4, and is ejected onto the non-sort tray 5 by the ejection roller pair 8c.

(B) In the case of no-fold sort mode Although special control may be performed depending on the sheet condition and the mode setting condition, first, the operation in the general sort mode in which origami is not present will be described. As a standby operation,
The deflector 3 is located in the direction of the solid line and the deflector 4 is also located in the direction of the solid line, and rotates the roller and the roller pairs 8a, 8b, 8d to 8g of the upper path of the folding device 204, respectively.
The upper and lower bin modules B ₁ and B ₂ are the uppermost bins B ₁₁ and B.
_The shift operation is performed so that ₂₁ comes to the sheet receiving position H facing the discharge roller pair 8g, 8p. The alignment wall 15 of the bin module stands by at the home position corresponding to the width of the sheet.

The grip / staple unit 9 is located at a position corresponding to the sheet bundle removal of the upper module B ₁ (see FIG. 2).
Move to the position (broken line) and wait. The moving body in the grip / staple unit 9 will be described with reference to FIG. The first-out gripper 10 stands by at the position shown in FIG. 16 so as not to obstruct the sheet on the bin when the bin in the module located on the left side of the grip / staple unit 9 is moved up and down.

Since the stapler 11 is not operated,
At 6, it moves to the front retracted position 11a indicated by the broken line. As shown by the broken line in FIG. 16, the transport gripper 12 grips the approximate center of the transported sheet bundle in the arrow F direction, and in the arrow G direction, the sheet advanced by the advance gripper 10 is advanced. The tip of the bundle stands by at a grippable position 12a.

The first gripper 10 and the transport gripper 12 stand by at the respective positions with the upper and lower grippers open.

Next, the stack unit 13 moves to the position shown by the broken line in FIG. 2 so that the stack of sheets conveyed by the grip / staple unit 9 can be received. The stack tray 116 inside the stack unit 13, the reference wall 117, and the pressing member 118 are
The upper surface of the stack tray 116 moves to a position where the stack of sheets can be received, and to other positions corresponding to the stack tray 116. The tip of the pressing member 118 is in a state of protruding toward the stack tray 116 side.

As described above, the sheet post-processing apparatus is in the standby state, the original is fed, the image is formed, and the sheet is fed, as in the non-sort mode. In FIG. 2, the first sheet passes through the upper path of the folding device, enters from the carry-in port 215, is conveyed by the deflector 3 above the vertical 1, and is further conveyed by the deflector 4 to the left side.
Then, it is discharged onto the bottle Bll.

[0099] detects that the sheet of the first sheet to the bin Bll in discharge sensor Sl8 is discharged, the bottle is shifted to one bin upwards, the bin B ₁₂ rises in sea Bok stowed position.
When the sheets having the same image are discharged to all the bins of the upper module by repeating the above operation, the original is replaced, and 2
An image is formed on the first original. As for the bin of the upper module, the lowermost bin (B _{16 in} FIG. 2) is at the sheet accommodation position, and the second sheet is accommodated in order from the lowermost bin. The above operation is repeated for all originals, and the operation for accommodating the sheets in the bin is completed. In this end state, if the number of originals is odd, the lowermost bin B ₁₆ is at the sheet storage position, and if the number of originals is even, the uppermost bin B ₁₁ is at the sheet storage position.

Next, the operation of taking out the sheet bundle from the bin is started. In the present embodiment, in the upper module, the sheet bundle take-out position, that is, the gripper / stapling unit 9 is on standby is the sheet accommodation. The position is two bins below the position. Therefore, the control of the stack take-out order changes depending on whether the number of originals is odd or even. (B)-(i) When the number of originals is an even number If the number of originals is an even number, the bin position after completion of sorting will be the same as at the start, and thus the state shown in FIG. In this case, do not take out from the bin B _{13 at} the bundle take-out position,
First, lower it by 2 bins to bring it to the state shown in FIG.
_The bundle is taken out in order from ₁₁ to B ₆ (FIG. 26).

Next, the container is raised by 2 bins to the state shown in FIG. 27, and the preparation for receiving the next sheet bundle is completed. In a continuous job, the number of originals is even at the next opportunity for the upper module B ₁ to accept a sheet. Therefore, if sorting is started in the state of FIG. 27, sorting is finished in the state of FIG. 27. In this case, since there is no bin corresponding to the bundle take-out position, the bundle is taken out from the lowermost bin B ₁₆ to B _{11 in} order by lowering it by 2 bins to bring it to the state of FIG. At this time, the state shown in FIG. 25 is entered, so that the state is raised by 2 bins and returned to the state shown in FIG. Therefore, when the upper module B ₁ repeatedly receives the sheet bundle a plurality of times, the above-described state change is repeated. (B)-(ii) When the number of originals is odd If the number of originals is odd, the bin position after sorting is completely opposite to that at the start. That is, if the sorting is started from the state of FIG. 24, the state is the state of FIG. 27 at the end. At this time, there is no bin corresponding to bundle extraction, so
The bin is lowered by 2 bins to the state shown in FIG. 26, and the bundle is taken out from the bottom bin B ₁₆ to B _{11 in} order. At this time, since the state shown in FIG. 25 is reached, the preparation for receiving the next sheet bundle is completed in the state shown in FIG. In the case of the same job, the number of originals is an odd number even at the next sheet receiving opportunity, so if sorting is started in FIG. 24, it ends in FIG. Therefore, also in this case, the state change described above is repeated.

In the case of the lower module, in the present embodiment, the relationship between the sheet receiving position of the bin and the bundle take-out position is opposite, and the bundle take-out position is located two bins higher. Although not described in detail here, the bin control in the lower module is controlled by repeating the state change in substantially the same manner as in the case of the upper module described above.

The subsequent operation of the sort mode will be described below.

The sheets stacked on the bin are aligned with the reference rods 14a and 14b on the front side shown in FIG. 4 by operating the alignment wall 15 in the direction orthogonal to the sheet conveyance. When sorting and alignment are completed, the sheet bundle S on the bin
In FIG. 17, the first-out clipper 10 is moved from the solid line position to the virtual line position while being opened, and then the sheet bundle S is moved.
Sandwich. The bin standing portion Bj shown in FIG. 15 is opened by the solenoid SLl and the sheet bundle can be conveyed.

As for the sheet bundle, the reference rod 14 shown in FIG.
1 a and 14 b, and the alignment rod 15 on the back side,
Both sides are regulated by the guide member 53a of No. 6, and the lower side is guided by the bin surface and the tilted bottle standing surface, the guide stay 53, and the upper direction by the guide stay 52, and is conveyed rightward in the drawing. . Then, it stops at the position shown by the solid line in FIG. 17, where the advance gripper 10 and the transport gripper 1
The bundle between the two is delivered.

First, the transport gripper 12, which has been waiting in the open position at the broken line in FIG. 16, holds the substantially central portion of the sheet bundle. Next, the first-out gripper 10 releases the clamp and prepares for the next conveyance. The transport gripper 12 is driven in the right direction of the arrow G in FIG. 16 to transport the sheet bundle in the right direction, and stops at an appropriate position according to the size. In this state, as shown in FIG. 28, the rear end of the sheet bundle S is dropped on the upper surface of the stack tray 116, the left side is regulated by the stacker reference wall 117, and the upper surface of the bundle is pressed by a solenoid. It is pressed by the member 118. From this state, the transport gripper 12 is opened, and the leading end of the sheet bundle is also dropped onto the stack tray 116.

The pressing member 118 has a function of preventing a deviation in the falling bundle.

Next, when the second bundle of sheets is being conveyed, the conveyance gripper 12 grasps the approximate center of the sheet bundle,
The operation up to the point where the bundle is transferred between the grippers is the same as that of the first bundle, so only the subsequent operation will be described.

After delivering the bundle, the transport gripper 12 moves by a predetermined amount in the direction of arrow F in FIG. At this time, the reference rod, the alignment wall, and the guide member 53a may escape so that the trailing edge of the sheet bundle is not regulated. Further, after the trailing edge of the sheet bundle is completely removed from these width regulating members, The transport gripper 12 may be moved in the arrow F direction. By this movement, when stacking the sheet bundle on the stack tray 116, it is possible to identify the sheet bundle from the first sheet bundle.

While the sheet is conveyed rightward by the conveying gripper 12, as shown in FIG.
Before reaching the predetermined position, the central portion of the sheets first drops onto the upper surface of the sheet bundle on the stack tray, and if the conveyance is continued, the conveyed sheet bundle S2 is aligned with the already stacked sheet bundle S1. May upset. At this time, FIG.
In pressing member 118 as by pressing the upper surface of the already-stacked sheet bundle S1, thereby preventing the deviation of the sheet bundle S ₁ of the already-stacked.

With respect to the sheet bundle stacked on the stack tray 116, the uppermost surface thereof is always detected by the sensor,
The stack tray 1116 is gradually lowered and controlled so that the distance between the upper grip / stapling unit 9 and the uppermost stacking surface is always constant.

Regarding the sheet bundle on the stack tray 116, the sheet bundle can be arbitrarily taken out when the stack unit 13 is not in operation. When the operator presses a take-out button (not shown), the stack unit 13 moves to the take-out position, and only the stack take-out cover can be opened and closed.

Further, after taking out the sheet bundle, the processing can be continued by closing the cover. (C) Case of Fold Sort Mode As described above, in the case of the fold sort mode, FIG.
After folding the large size paper into a desired small size by the folding device 204, it passes through the same conveyance path as a normal sheet and is discharged to the bin by the discharge rollers 8g and 8p.

However, the storage of the folding mode in which the origami is included is limited to the uppermost bins B ₁₁ and B ₂₁ of each bin module.

The uppermost bins B ₁₁ and B ₂₁ are lowered to the normal sheet receiving position H for accommodating the unfolded sheets and to this position by one step from the pair and lowered by one step to accommodate the sheets including the folded sheets. It is movable to position I and. When the folded sheets are stored, the sheet receiving positions of the uppermost bins B ₁₁ and B ₂₁ are set to the position I lowered by one step (see FIGS. 5 and 6).

By lowering the uppermost bin by one step, the space above the uppermost bin is expanded, and there is room for storing thick sheets such as origami paper, and a plurality of sheets can be stacked.

Further, the descending amount of the descending position I is set so that the extension line of the ejecting roller 8 in the ejecting direction exceeds the folding portion of the origami paper on the uppermost bins B ₁₁ and B ₂₁ .

Therefore, as shown in FIG. 30, the folding device 2
Even if the folded portion folded at 04 swells to some extent due to the restoring force of the sheet, the leading edge of the sheet to be discharged next is stacked over the folded portion, and therefore does not cause a paper jam.

When the stacking of sheets is completed, the above (B)
Similarly to the above, the bundle transfer to the stacker by the gripper 10 is performed.

The above operation is the uppermost bin B of each module.
_This process is repeated for each of ₁₁ and B ₂₁ , and the desired number of copies is processed.

In the above embodiment, the uppermost bins B ₁₁ and B ₂₁ are preliminarily waited at the lowered position I for stacking in accordance with the folding mode setting, but the standby position is the normal sheet receiving position. It may be set to H and gradually moved to the lowered position I as the origami sheets are stacked. In this case, the highest bin B
_11, depending on the sheet stacking amount of B _21, the uppermost bin B _11, B ₂₁
The descending amount of increases.

That is, first, the standby position of the uppermost bin is set to H, the number of discharged sheets is counted, and the control device 30
In the case of 0, the encoder 21 causes the bin shift motor M1 to normally rotate by the number of pulses corresponding to the number, and the uppermost bin is gradually lowered.

According to this method, since the distance between the paper surface of the bin and the discharge roller 8 is kept substantially constant, it is possible to improve the aligning stacking property when discharging the sheets. Further, the effect of enlarging the space above the uppermost bin and improving the storage capacity of the origami paper is the same as in the case described above.

[0124]

As described above, according to the present invention,
The stacking means for storing discharged sheets can be moved between an unfolded sheet receiving position for receiving a normal sheet and a folded sheet receiving position, and when the folded sheet is received by the stacking means, the stacking means is moved to the unfolded sheet receiving position. Since it was lowered to the position where it was lowered by one step,
The space above the stacking means is enlarged, and a room is created for storing thick sheets such as origami paper, and a plurality of sheets can be stacked.

The stacking means for accommodating the folded sheets is the uppermost stacking means, and the stacking means at the folded sheet receiving position is arranged so that the extension line in the conveying direction of the discharging means can pass over the stacked sheets. Since the folded sheet is lowered to the stepped position, even if the folded sheet swells on the stacking unit due to the restoring force of the folded sheet, the leading end of the sheet to be discharged next is caught on the uppermost folded sheet, It does not cause a paper jam.

Further, since the descending amount of the stacking unit when stacking folded sheets is increased in proportion to the sheet stacking amount, the sheet surface of the uppermost sheet on the stacking unit and the sheet by the discharging unit are Since the discharge position and the discharge position are kept substantially constant, it is possible to improve the alignment stacking property at the time of discharging the sheets. In addition, the space above the uppermost stacking means can be expanded, and the origami storability can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a sheet post-processing device according to a first embodiment of the present invention and an image forming apparatus main body to which the sheet post-processing device is connected.

FIG. 2 is a vertical sectional front view of the sheet post-processing apparatus.

FIG. 3 is a perspective view of the bin module.

FIG. 4 is a plan view of the bin module.

5 (a) is a front view of a bin module, FIG.
(B) The figure is a front view of a bin module (comparative view).

FIG. 6 is a front view of the same bin module.

FIG. 7 is an operation diagram of the same bottle.

FIG. 8 is an operation diagram of the same bottle.

FIG. 9 is a plan view of the matching wall driving unit.

FIG. 10 is a side view of the matching wall driving unit.

FIG. 11 is a front view of the folding device.

FIG. 12 is a folding operation diagram of the folding device.

FIG. 13 is a folding operation diagram of the folding device.

FIG. 14 is a plan view of the bin standing drive unit.

FIG. 15 is a side view of the bin standing drive unit.

FIG. 16 is a plan view of the grip / staple unit.

FIG. 17 is a side view of the grip / staple unit.

FIG. 18 is a front view of the gripper portion.

FIG. 19 is a plan view of the first-out gripper driving unit.

FIG. 20 is a side view of the first-out gripper driving unit.

FIG. 21 is a plan view of the transport gripper driving unit.

FIG. 22 is a side view of the transport gripper driving unit.

FIG. 23 is a schematic drive diagram of the transport system.

FIG. 24 is an operation diagram of the same bottle.

FIG. 25 is an operation diagram of the same bottle.

FIG. 26 is an operation diagram of the same bottle.

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

FIG. 28 is an operation diagram similarly showing the effect of the stack pressing member.

FIG. 29 is an operation diagram similarly showing the effect of the stack pressing member.

FIG. 30 is an operation diagram of stacking folded sheets.

FIG. 31 is a side view showing an example of a conventional sheet post-processing apparatus.

FIG. 32 is a side view showing another example of the conventional sheet post-processing device.

FIG. 33 is an operation diagram of origami stacking in the conventional apparatus.

[Explanation of symbols]

S Sheet B ₁ (B ₁₁ ~B _1n) first bin module B ₂ (B ₂₁ ~B _2n) second bin module _{B 11 ~B 16, B 21 ~B} 26 bins (stacking means) B _11, B ₂₁ Uppermost stacking means H Sheet receiving position for normal (unfolded) sheets I Position lowered one step from sheet receiving position (position for storing folded sheets) 8g, 8p Ejection roller pair (sheet ejection device) 9 Grip / staple Unit 10 advance clipper 11 stapler (post-processing means) 12 transport gripper 13 stack unit 16a, 16b, 16c lead cam (moving means) 201 copying machine main body (image forming apparatus main body) 203 sheet post-processing device 204 folding device 205 staple / stack device 271 Discharge roller of copy machine main body 300 Control device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriyuki Miyake 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Hiromichi Tsujino 3-30-2 Shimomaruko, Ota-ku, Tokyo Kya Non-Incorporated (72) Inventor Koichi Murakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yoshinori Isobe 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (4)

[Claims] 1. A stacking means for arranging discharged sheets in a plurality of stages for storing the sheets, a sheet discharging means for discharging the sheets to the stacking means at a sheet receiving position, and a stacking means for receiving the sheets. A sheet post-processing apparatus comprising: a moving unit for moving the sheet to a position; and a folding unit that bends the discharged sheet in a direction perpendicular to the sheet conveying direction to make the sheet have a desired size. The stacking means is movable between an unfolded sheet receiving position for storing a sheet bundle that does not include folded sheets and a folded sheet receiving position for storing a sheet bundle that includes folded sheets, and the unfolded sheet receiving position. Is located at a position lower than the unfolded sheet receiving position. 2. The stacking means for stacking the folded sheets,
The uppermost stacking means, and the folded sheet receiving position of the stacking means is such that the extension line in the sheet discharging direction by the sheet discharging means passes over the sheets stacked on the stacking means. The sheet post-processing apparatus according to claim 1, wherein the sheet post-processing apparatus descends with respect to the position. 3. The sheet post-processing apparatus according to claim 1, wherein the descending amount of the stacking unit to the folded sheet receiving position increases in proportion to the sheet stacking amount on the stacking unit. 4. An image forming apparatus main body having an image forming unit for forming an image on a sheet, to which the sheet post-processing apparatus according to claim 1 is connected, and which is connected to the sheet post-processing apparatus. An image forming apparatus comprising: