JP2001240292A - Folded sheet loading device and image fomring device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a folded sheet loading device not needing a wide loading space for folded sheets in its delivery tray. SOLUTION: This folded sheet loading device 79 is provided with the paper delivery tray 80 provided with a recessed part 82 for receiving an end part Pa of the folded sheet P delivered in a state that its folded ends are directed forward, on a downstream side edge in the folded sheet delivery direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet stacking apparatus for stacking folded sheets or a bundle of sheets, and an image forming apparatus such as a copying machine, a printer, a facsimile, and a composite machine including the apparatus. And about.

[0002]

2. Description of the Related Art Conventionally, there is an image forming apparatus in which a sheet post-processing apparatus is provided in a main body. The sheet post-processing apparatus receives a plurality of sheets on which images are formed in the image forming apparatus main body in a state of being sequentially stacked, aligns the sheets to form a sheet bundle, and binds a central portion of the sheet bundle with a stapler. In the sheet folding device, 2
The sheet bundle is folded into a bound document shaped like a weekly magazine, and is discharged to a discharge tray.

A sheet folding apparatus in such a sheet post-processing apparatus receives and conveys a conveyed sheet bundle by a pair of sheet folding rotating members, and an intermediate portion of the sheet is a part where the sheet folding rotating members are in contact with each other. When the sheet folding member comes to the opposing position, the sheet pushing member pushes the intermediate portion between the sheet folding members, and the intermediate member is pushed into contact between the sheet folding rotating members, and the sheet bundle is folded into two by the rotation of the sheet folding rotating member pair. .

However, the folded sheet bundle discharged to the discharge tray is sequentially discharged to the discharge tray with the folded side first and stacked, but the folded side swells more than the open end, so that the folded sheet bundle is folded. Side is raised and will be stacked in an unstable state.

A discharge tray 85 shown in FIG. 18 is provided as a discharge tray that addresses such a problem. The discharge tray 85 supports the open end Pb of the folded sheet bundle P with a projection 85a protruding above the discharge tray, so that the sheet bundle P can be horizontally stacked in a stable state. ing.

There is also a discharge tray 86 shown in FIG. In the discharge tray 86, the moving member 87 moves in accordance with the number of stacked sheet bundles. With the movement of the moving member 87, the stacking position of the sheet bundle is sequentially shifted like a roof tile, and the sheet is shifted. The bundles are stacked in a plane, and are stably stacked.

The sheets include plain paper, resin substitutes for plain paper, and cardboard.

[0008]

However, the discharge tray 85 in FIG. 18 increases in proportion to the number of stacked sheet bundles.
Accordingly, a large space is required above the discharge tray.

Further, the discharge tray 86 in FIG. 19 needs to be lengthened in proportion to the number of stacked sheet bundles, and accordingly requires a large stacking area.

In the above description, the case where the folded sheets are a bundle of sheets has been described. However, a similar problem occurs when one folded sheet is stacked and stacked.

[0011] The present invention provides a sheet stacking apparatus provided with a discharge tray which does not require a large space for stacking folded sheets,
It is an object to provide an image forming apparatus provided with the sheet stacking device.

[0012]

In order to achieve the above object, a folded sheet stacking apparatus according to the present invention is characterized in that a concave portion for receiving the end of a folded sheet discharged with the folded end first is provided with the folded sheet. And a discharge tray formed at the downstream end in the discharge direction.

At the downstream end of the discharge tray, there is provided a stopper member which receives the end of the folded sheet and can be displaced downstream in the discharge direction of the folded sheet.

The initial position of the stopper member is set at a position for receiving a folded sheet of the maximum size.

In order to achieve the above object, an image forming apparatus according to the present invention comprises an image forming means for forming an image on a sheet, and a sheet folding apparatus for folding a sheet on which an image is formed by the image forming means to form a folded sheet. A folding sheet stacking apparatus for receiving the folded sheet created by the sheet folding apparatus.

To achieve the above object, an image forming apparatus according to the present invention comprises an image forming means for forming an image on a sheet, and a sheet binding apparatus for binding and binding the sheets on which images are formed by the image forming means. A sheet folding device that folds a sheet bundle bound by the sheet bundle binding device to create a folded sheet bundle, and any one of the above-described folded sheet stacking devices that receives the folded sheet bundle created by the sheet folding device , Is provided.

(Operation) The discharge tray receives and stacks the folded sheets sequentially discharged one after another with the folded end first. At this time, the folded end of the folded sheet is swollen, but the discharge tray receives the swollen portion of the lowermost folded sheet by the concave portion. For this reason, the discharge tray alleviates the difference in thickness between the bulged portion of the folded sheet and the open end of the folded sheet, and supports the folded sheets stacked in a substantially horizontal state.

When the discharge tray receives the folded sheets sequentially discharged one after another with the folded end first, the folded sheets stacked earlier are stacked later by the contact resistance between the folded sheets. The folded sheet may be moved downstream in the folded sheet discharge direction. In such a case, the stopper member provided on the downstream side of the discharge tray in the folded sheet transport direction is displaced downstream in the folded sheet discharge direction while receiving the moved folded sheet. Thus, the folded sheets are stacked with their positions slightly shifted downstream in the folded sheet discharge direction without the swollen portions overlapping in the vertical direction, and are substantially horizontally supported by the discharge tray.

Since the discharge tray can be displaced even when the folded sheet is taken out, there is no hindrance to taking out the folded sheet.

In the above description of the operation, the folded sheet is
This includes any case where there is one sheet and a case where the sheet is a bundle of sheets. Therefore,
In the claims, the folded sheet includes any one of a single sheet and a case where the sheets are bundled.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

(Main Body of Copying Machine) A main body of a copying machine, which is an example of an image forming apparatus having a sheet post-processing device including a folding unit (sheet folding device) for folding a sheet according to the present invention, will be described with reference to FIG. Will be explained.

The main body 1 of the copying machine 20 includes a platen glass 906 as a document table, a light source 907, and a lens system 90.
8, a paper feeding unit 909, an image forming unit 902, and the like. An original D is placed on a platen glass 906
An automatic document feeder 940 for automatically feeding the original is provided.

The paper feeding section 909 has cassettes 910 and 911 which house recording sheets S and are detachable from the main body 1, and a deck 913 which is arranged in a peddy style 912. An image forming unit (image forming unit) 902 includes a cylindrical photosensitive drum 914 and a developing device 9 disposed around the photosensitive drum 914.
15, a transfer charger 916, a separation charger 917, a cleaner 918, a primary charger 919, and the like. On the downstream side of the image forming unit 902, a conveying device 920, a fixing device 90
4, a pair of paper discharge rollers 1a, 1b, etc. are provided.

The operation of each mechanism in the main body 1 of the copying machine 20 will be described.

When a sheet feed signal is output from the control device 921 provided in the main body 1, sheets S are fed from the cassettes 910, 911 or the deck 913. On the other hand, the light source 9 is attached to the original D placed on the platen glass 906.
Light reflected from 07 is reflected on the photosensitive drum 914 via the lens system 908. Photosensitive drum 914
Are charged in advance by a primary charger 919, and an electrostatic latent image is formed by irradiation with light.
Next, the developing device 915 develops the electrostatic latent image to form a toner image.

The sheet S fed from the sheet feeding unit 909 is
The skew is corrected by the registration rollers 901, and the skew is sent to the image forming unit 902 at the same timing. In the image forming unit 902, the toner image on the photosensitive drum 914 is transferred to the sheet S sent by the transfer charger 916. The sheet S to which the toner image has been transferred is placed on the separation charger 9.
And 17 is charged to a polarity opposite to that of the transfer electric device 916,
It is separated from the photosensitive drum 914.

The separated sheet S is conveyed to the fixing device 904 by the conveying device 920, and the transferred image is permanently fixed on the sheet S by the fixing device 904. The sheet S on which the image has been fixed is transferred to the main body 1 by the discharge roller pairs 1a and 1b.
Is discharged to the outside.

In this manner, an image is formed on the sheet S fed from the sheet feeding unit 909, and the sheet S is discharged to the sheet post-processing device 2.

(Sheet Post-Processing Apparatus) (Sheet receiving and aligning portion of sheet post-processing apparatus) FIG.
, Sheet post-processing equipment (also known as “finisher”)
2 is provided on the side of the main body 1 of the copying machine.

The paper discharge roller 1a provided on the main body 1 of the copying machine 20 and the paper discharge roller 1b pressed by the paper discharge roller 1a constitute a paper discharge roller pair. The transport guide pair 3 receives the sheet discharged from the sheet discharge roller pair 1a, 1b of the copying machine 20, and guides the sheet into the sheet post-processing device 2. The sheet detection sensor 4 detects a sheet conveyed in the conveyance guide 3. The sheet detection of the sheet detection sensor 4 determines the alignment timing and the like, and also functions to detect whether the sheet is jammed in the conveyance guide 3 (whether the sheet is jammed). The discharge roller pair 6 rotates so as to pinch and convey the sheet in the conveyance guide 3.

The processing tray 8 receives sheets sequentially discharged by the discharge roller pair 6 and stacks them. The processing tray 8 is provided with a pair of alignment plates 9 that guide the both ends of the width of the sheet discharged by the discharge roller pair 6 and align the width of the sheet. As shown in FIG. 2, the alignment plates 9 and 9 are arranged at both ends in the width direction crossing the sheet conveyance direction. Each matching plate 9, 9
Is a pin-on 1 provided on a shaft of an alignment motor 14 composed of a stepping motor disposed below the processing tray 8.
5 is provided on the processing tray 8 so as to be appropriately moved in the sheet width direction by the rotation of the alignment motor 14 on the front side and the alignment motor 14 on the back side. ing.

In FIG. 1, a carry-in guide 7 is a guide for guiding a sheet discharged from the discharge roller pair 6 into the processing tray 8. A paddle 17 is provided below the loading guide 7.
Is provided. The paddle 17 is formed in a semicircular shape from a rubber material having a certain elasticity in order to reliably carry in the sheet, is in contact with the upper surface of the sheet, and rotates about a shaft 17a. I have. Also, paddle 17
Are fins 17 extending radially around an axis 17a.
b and the paddle surface 17c are integrally formed. The paddle 17 is easily deformed as the sheets are stored in the processing tray 8, and gives an appropriate conveying force to the sheets.

In FIG. 1, a first pulley 10 provided on a first pulley shaft 10a and a second pulley 11 provided on a second pulley shaft 11a are further provided on the processing tray 8. Have been. A transfer belt 12 is stretched between the first pulley 10 and the second pulley 11, and an extruding claw 13 is protruded from a part of the outer periphery of the transfer belt 12.

A lower conveying roller 18 is coaxially provided on the first pulley shaft 10a. Transport lower roller 18
The upper transport roller 19 moves between a position where the upper transport roller 19 comes into pressure contact with the lower transport roller 18 (a position indicated by a dotted line in FIG. 1) and a separated position away from the lower transport roller 18 (a solid line in FIG. 1). It is provided to be.

The stopper 21 is discharged to the processing tray 8 by the discharge roller pair 6 and falls by its own weight.
7, the end of the sheet which is moved by rotation is received and regulated. One end of the stopper 12 is supported on the first pulley shaft 10a, and is always projected to a position for regulating the sheet end by a spring or the like (not shown).

(Stapler Unit of Sheet Post-Processing Apparatus) The stapler unit (sheet bundle binding apparatus) 30
As shown by a two-dot chain line in FIG. 1, the unit is unitized and can be pulled out from the sheet post-processing apparatus 2. The stapler unit 30 has a needle driving head unit 31 having a needle cartridge (not shown) on the lower side of the transport passage, and an anvil unit 33 for bending a needle driven from the needle driving head unit 31 upward. I have. The needle driving head unit 31 and the anvil unit 33 are movable in a direction (the front and back sides of the paper) that intersects the sheet conveyance direction (from right to left in FIG. 1). Guide rods 33, 34
Are provided above and below so as to guide the movement (shift movement) of the anvil unit 32 and the driving head unit 31 in a direction intersecting the sheet conveying direction. The screw shafts 35 and 36 are screw shafts for shifting the anvil unit 32 and the driving head unit 31. An anvil drive shaft 37 and a head drive shaft 38
Is a drive shaft for causing the anvil unit 32 and the driving head unit 31 to perform a needle driving operation and a needle bending operation, respectively. The conveyance guide 39 guides a sheet bundle conveyed in the stapler unit 30.

(Folding Unit of Sheet Post-Processing Apparatus (Sheet Folding Apparatus)) The sheet bundle folding unit 50 is unitized as shown by a two-dot chain line in FIG. It can be withdrawn from the processing device 2. Sheet bundle transport guide 53
Is adapted to guide a sheet bundle conveyed by being sandwiched between the upper conveying roller 19 and the lower conveying roller 18 located on the entrance side of the stapler unit 30. The upper bundle transfer roller 51 is provided on the entrance side of the folding unit 50. The lower transport roller 52 is disposed to face the bundle transport roller pair 51. The upper bundle transfer roller 51 moves between a position pressed against the lower bundle transfer roller 52 (the position indicated by the solid line in FIG. 1) and a position separated therefrom (the position indicated by the alternate long and short dash line in FIG. 1). I have. The upper bundle transport roller 51 is moved until the leading end portion of the sheet bundle passes through the upper bundle transport roller 51 and the lower bundle transport roller 52 by the upper transport roller 19 and the lower transport roller 18 positioned on the entrance side of the stapler unit 30. , Is in a state of being separated from the lower transport roller 52 (the position indicated by the one-dot chain line in FIG. 1).
(The position indicated by the solid line in FIG. 1).

A bundle detection sensor 5 for detecting the end of the sheet bundle
When the leading end of the sheet bundle is detected, the bundle transport upper roller 5
1 is pressed by the upper bundle transfer roller 52 and used to set and control the folding position of the sheet bundle in the transfer direction. The thrust plate 55 has a tip thickness of 0.2
It is a stainless steel plate of about 5 mm. The folding roller pair (sheet folding rotating body pair) 57a, 57b is a cylindrical roller having a partially flat portion extending in a direction intersecting the sheet bundle conveying direction, and is urged in the direction of pressing each other to rotate, respectively. It has become.

The pushing plate 55 includes a pair of folding rollers 57a and 57.
b, the leading edge of the folding roller pair 57a, 57b moves to the vicinity of the nip thereof. Around the upper side of the pair of folding rollers 57a and 57b, backup guides 59a and 59b having a substantially arc shape for guiding conveyance of the sheet bundle together with the conveyance guide 53 are provided. This backup guide 59a, 59
b releases the peripheral surface of the folding roller pair 57a, 57b with respect to the sheet bundle when the leading edge of the pushing plate 55 moves near the nip of the pair of folding rollers 57a, 57b in conjunction with the vertical movement of the pushing plate 55. So that it moves. The sheet bundle guide 56 guides a sheet bundle conveyed by being sandwiched between the upper bundle transfer roller 51 and the lower bundle transfer roller 52, and the leading end (downstream end) of the sheet bundle passes through the sheet bundle passage 58. So that it hangs down. Among the bundle discharge roller pairs 60a and 60b, the roller denoted by reference numeral 60a is a driving roller, and the roller denoted by reference numeral 60b is a driven roller.

The bundle stacking tray 80 of the folded sheet bundle is folded by the folding operation of the pair of folding rollers 57a and 57b.
The sheet bundle discharged by the pair of bundle discharge rollers 60a and 60b is stacked. The folded sheet presser 81 presses a sheet bundle discharged into the bundle stacking tray 80 with a spring or its own weight.

FIGS. 12 to 14 show a folded sheet stacking device 79 which is a feature of the present invention. The folded sheet stacking device 79 is connected to the bottom 8 of the bundle stacking tray 80 (discharge tray).
0a, a concave portion 82 for absorbing the bulge on the folding side of the sheet bundle, and a rotating shaft 83a provided near the outlet of the bundle stacking tray 80 as a fulcrum. And a bundle stopper (stopper member) 83 which can be tilted.

The sheet bundle passage 58 is provided in the sheet post-processing apparatus 2.
Is formed as a space in which a sheet bundle can move.

The elevating tray 90 moves up and down along the frame of the sheet post-processing device 2 and moves between a position indicated by a solid line and a position indicated by a two-dot chain line in FIG. The elevating tray 90 can move up and down by engaging the elevating tray support portion 92 with a part of a belt that is rotated and moved by driving means such as an elevating tray motor 155 (see FIG. 16). The paper surface sensor 93 detects the uppermost surface of the sheet on the elevating tray 90.
The rear end guide 94 guides the rear end of the sheet on the elevating tray 91 which moves up and down in the vertical direction.
The auxiliary tray 91 is provided so as to be able to be pulled out of the elevating tray 90, and is used in a pulled-out state when storing large-sized sheets or the like.

Detailed configurations of the processing tray 8 of the sheet post-processing apparatus 2 and the folding unit 50 of the stapler unit 30 will be described with reference to FIG.

FIG. 2 is a plan view of the processing tray 8.
The first pulley 10 and the second pulley 11 stretch the transfer belt 12 and are located on substantially both sides in the center in the sheet width direction.
On the first pulley shaft 10a, two conveyance lower rollers 18 are provided on both sides substantially at the center in the sheet width direction. The transport lower roller 18 is a tire type hollow roller.

As described above, two first pulleys 10 for rotating the transfer belt 12 are arranged on the first pulley shaft 10a. In FIG. 1, the first pulley 10 is driven and rotated by a one-way clutch 75 interposed between the first pulley 10 and the first pulley shaft 10a, and is rotated clockwise in FIG. In the rotation in the direction, the drive is cut off and stopped. The first pulley shaft 10a is provided with a pulley 7 fixed to the first pulley shaft 10a.
3. It is connected to a motor shaft 70a of a stepping motor 70 as a transport drive source via a timing belt 74 and gear pulleys 72 and 71.

Accordingly, the stepping motor 70 moves the sheet on the processing tray 8 in the stapling direction shown in FIG. 1 (FIGS. 1 and 2).
When rotating in the direction of movement (in the direction of arrow B), the transport lower roller 18 fixed to the first pulley shaft 10a is driven to rotate, but a driving force is transmitted to the transfer belt 12 by the one-way clutch 75. The transfer belt 12
In a stopped state. When the stepping motor 70 rotates to move the sheet toward the elevating tray 90, both the lower conveying roller 18 and the transfer belt 12 rotate in the direction of the elevating tray 90 (the direction of the arrow A in FIGS. 1 and 2).

The transfer belt 12 will be described with reference to FIG. One-way clutch 75 is attached to first pulley shaft 10a.
An extruding claw 13 is provided on the transfer belt 12 stretched between the first pulley 10 and the second pulley 11 interposed therebetween. In order to position the pushing claw 13 at the home position (the position of HP in FIG. 3), the pushing claw 13
An extruding claw sensor 76 and an extruding claw detection arm 77 of the extruding claw 13 that engage with the processing claw 13 are provided on the lower surface of the processing tray 8. The position where the push-out claw 13 is moved by the transfer belt 12 to push the push-out claw detection arm 77 and the push-out claw sensor 76 switches from OFF to ON is defined as a home position (HP). FIG. 3 shows the positional relationship at this time. Assuming that the nip between the lower transport roller 18 and the upper transport roller 19 is P, the length from the nip P to the stopper 21 is Ll, and the length from the nip P to the pushing claw 13 along the transport belt 12 is L2. Ll <L2)
Is set to

The upper roller 19 is lowered and pressed toward the lower roller 18 by the operation of a cam or the like (not shown). Thereafter, the transport stepping motor 70 is rotated to rotate the first pulley rotating shaft 10a in a counterclockwise direction (FIGS. 1 and 2).
(In the direction of arrow A), the transport lower roller 18 rotates, and the sheet bundle is also moved toward the elevating tray 90 (in the direction of arrow A).
Move to.

The upper transport roller 19 is also rotated by a stepping motor 70 (see FIG. 2). Therefore, the sheet bundle is moved from the position of the stopper 21 which has entered the stapler unit 30 side to the lower conveying roller 18.
When the nip position P is reached, the transfer belt 12 is moved.
The pushing claw 13 hits with the rotation of, and is conveyed to the elevating tray 90 while being pushed by the pushing claw 13 in the direction of each arrow A in FIG. In this case, the length relationship described above is (L
Since l <L2, the pushing claw 13 pushes up from the lower side of the sheet bundle (the right end side in FIG. 3), and always pushes out the end of the sheet bundle in a vertical state. This prevents extra stress or the like from occurring when the sheet bundle is transferred.

When performing the binding process, the push-out claw 13 is moved counterclockwise from the position of HP in FIG. 3 and is moved from the stopper 21 by the pair of rollers 18 and 19 which convey the sheet bundle synchronously. After receiving the sheet bundle, push it out.

On the other hand, if the sheets conveyed to the processing tray 8 are not bound by the stapler unit 30, there is no need to carry in the sheet bundle to the position of the stopper 21.
To move the push-out claw 13 from the HP position in FIG. 3 to the movement standby position ((L2 + α)) in the direction of the elevating tray 90 beyond the nip point between the lower conveyance roller 18 and the upper conveyance roller 19, 3 PreHP position). This (L2 + α) can be set by counting the number of steps of the stepping motor 70. Therefore, in the case of a sheet that does not require a binding process, the sheet post-processing apparatus 2 moves the pushing claw to the position of PreHP in advance without transferring the sheet to the stopper 21 and stacks the sheet before stacking the sheet on the elevating tray 90. So you can push it out
It is possible to cope with a copying machine having a high processing speed.

Note that, as shown in FIG.
The position of the PreHP is the loading guide 7 and the pushing claw 13.
When the upper end of the sheet is overlapped, the sheets conveyed one by one can be reliably stacked at the position of the push-out claw 13 at the position of PreHP. Then, the push-out claw 13 can quickly discharge the sheet bundle to the elevating tray 90 thereafter.

(Detailed Description of Stapler Unit) In FIGS. 4 and 5, the stapler unit 30 includes left and right unit frames 40 and 41 and the frames 40 and 4.
It has guide rods 33 and 34, screw shafts 35 and 36, drive shafts 37 and 38 provided between them, an anvil unit 32 above, and a driving head unit 31 below. Head unit 3 driven into screw shaft 36
1 is engaged, and the rotation of the screw shaft 36 causes the head unit 31 to move in the left-right direction in FIG. The anvil unit 32 has a similar mounting configuration. The screw shaft 36 is connected to a stapler slide motor 42 via a gear outside the unit frame 41. The drive of the stapler slide motor 42 is also transmitted to the anvil unit 32 by the timing belt 43. For this reason, the head unit 31 and the anvil unit 32 move in a direction intersecting the sheet conveying direction (the left-right direction in FIG. 4) without shifting the vertical position.

Accordingly, the stapler slide motor 42 is driven in accordance with the width of the sheet, so that the head unit 31,
When the anvil unit 32 is controlled to move to a predetermined position, the slurr needle can be freely driven into an arbitrary position.

Driving force such as movement of a head for driving a needle (not shown) in the head unit 31, movement of the needle, and bending movement of the needle in the anvil unit 32 are coupled from the sheet post-processing apparatus 2 side. The signal is received by the device 44 and is also transmitted to the anvil unit 32 by the timing belt 45 on the unit frame 40 side. Moving arm 23 (see FIG. 5) and stopper 2
1 is a connecting pin 23c, a connecting lever 22, a connecting pin 21
are connected by a. The stopper 21 is supported on the pulley shaft 10a.

Referring to FIG. 4 and FIG.
A description will be given of a configuration in which the stopper 21 that sets the needle driving position at the end of the sheet bundle by moving the sheet 1 in the sheet width direction moves in and out of the staple path. Below the driving head unit 31 in FIG. 4, a stopper engaging projection 24 capable of engaging the stopper 21 with the moving arm 23 is provided. By the movement of the head unit 31 and the engagement of the stopper engagement projection 24 with the movement arm projection 23b, the movement arm 23 rotates counterclockwise about the rotation shaft 23a as shown in FIG. Move to the position indicated by the two-dot chain line. Therefore, the stopper 21 does not hinder the movement of the head unit 31 and the anvil unit 32 in the sheet width direction.

(Detailed Description of Folding Unit) The folding unit 50 will be described with reference to FIGS.

FIG. 6 shows a folding unit (sheet folding apparatus).
50 is a view of a folding unit frame 49 of FIG. Since the folding unit 50 is provided so as to be able to be pulled out to the sheet post-processing apparatus 2, the frame on the far side in FIG. 6 is also formed in a similar shape. The folding unit frame 49 of the folding unit 50 includes a folding roller driving shaft 61 as a rotation shaft of the folding roller 57a, and a driving shaft 6 of the bundle discharging roller 60a.
9a is provided. The drive shaft 62 of one of the folding rollers 57b is attached to a folding roller holder 63 that rotates about the drive shaft 69b of the bundle discharge roller 60b as a fulcrum.
A tension spring 67 having a tension of about 5 kg is stretched between the folding roller holder 63 and the folding unit frame 49. In the folding unit frame 49, a hole that allows the folding roller drive shaft 62 to move by the folding roller holder 63, that is, a frame guide 64 is formed.

Accordingly, when the sheet bundle is folded and conveyed by the pair of folding rollers 57a and 57b, a constant pressure can be applied to the sheet bundle by the tension spring 67, and a reliable folding operation can be performed. it can.

The folding unit frame 49 has a veneer 5
Rollers 66, 6 standing on support holder 110 supporting
A veneer frame guide 65 is formed as an elongated hole for guiding the movement of the frame 6. This veneer frame guide 65
As a result, the pushing plate 55 can move toward the folding roller pair 57a, 57b.

The folding unit frame 49 further includes
A drive shaft 111 that rotatably supports a cam plate 114 that moves the thrust plate 55 is provided.

Further, the folding unit frame 49 is also provided with an upper roller shaft 101 of a bundle conveying upper roller 51 for conveying the sheet bundle into the folding unit 50 and a lower roller shaft 103 of the bundle conveying lower roller 52. The folding unit frame 49 is provided with a mechanism for positioning the upper bundle transport roller 51 at a position separated from the lower bundle transport roller 52 until the sheet bundle is carried into the folding unit 50.

The upper roller shaft 1 of the pair of bundle transport rollers 51 and 52
01 is supported by the bearing holder 102. A cam follower 112 is provided upright at one end of the bearing holder 102. The cam follower 112 is engaged with an upper roller moving cam 68 rotatably attached to the folding unit frame 49. Further, a tension spring 104 having a tension of about 300 g is stretched between the other end of the bearing holder 102 and the lower roller shaft 103. The tension spring 104 always urges the upper bundle transfer roller 51 toward the lower bundle transfer roller 52. The rotation of the upper roller moving cam 68 causes the bearing holder 102 to move the tension spring 1
The bundle conveying upper roller 51 is moved up and down against or pulled by the sheet conveying roller 04, and moved to a position separated from the bundle conveying lower roller 52 and to a position where the roller is pressed against the roller.

FIG. 7 shows a mechanism for performing the folding operation, which is provided inside the folding unit frame 49 shown in FIG.

A cam plate 114 is fixedly mounted on the cam drive shaft 111.
Is driven to rotate. This cam plate 114 has a cam follower 116 erected substantially at the center of an operating arm 115 rotatable about a shaft 113 as a fulcrum.
14b. A push plate 55 is attached to the distal end side of the operation arm 115 via a support holder 110.

Accordingly, when the cam plate 114 is rotationally driven, the operating arm 115 also performs the elevating operation, and the pushing plate 55 attached to the operating arm 115 also performs the elevating operation. The thickness of the pushing plate 55 that presses the sheet bundle is about 0.
It is formed of a 25 mm stainless steel material. Next, the support holder 110 that supports the thrust plate 55 includes the folding roller pair 5.
Backup guide 5 to guide around 7a and 57b
9a, 59b.

The backup guides 59a and 59b are disposed so as to cover the outer peripheral surfaces of the pair of cylindrical folding rollers 57a and 57b extending in the direction intersecting the sheet conveyance direction, and center on the axes 61 and 62 of the folding roller pairs 57a and 57b. Thus, the folding rollers 57a and 57b are rotatable with respect to the outer peripheral surfaces thereof.

Lever pieces 119 and 120 are provided at the outer peripheral ends of the backup guides 59a and 59b, respectively. The backup guides 59 a and 59 b are pulled by the pulling 121. Lever piece 119,
120 is a bifurcated operating piece 1 of the support holder 110
17 and 118 are abutted and supported. Accordingly, when the backup guides 59a and 59b are in the state shown in FIG. 7A, they are located at positions that cover the outer peripheral surfaces of the pair of folding rollers 57a and 57b on the transport path side, and the sheet bundle is folded by the pair of folding rollers 57a and 57b.
The guide can be guided in a state in which it is sufficiently in contact with the rubber surface of the sheet 57b, and also functions as a guide for backing up (supporting) the sheet bundle. The backup guides 59a and 59b usually function as a lower transport guide of the sheet bundle together with the bundle transport guide.

FIG. 7 shows the operation of folding the sheet bundle.
As shown in (b), the operating piece 117,1 of the support holder 110
In response to the lowering of 18, the lever pieces 119 and 120 are pushed up. The result is the backup guide 59a, 59b
Is rotated around the shafts 61 and 62 against the pulling 121 so that the outer peripheral surfaces of the pair of folding rollers 57a and 57b reliably contact the sheet bundle.

The drive transmission system of the folding unit 50 will be described. The drive transmission system includes a rotation and separation / contact system of the upper bundle transfer roller 51 and the lower bundle transfer roller 52 shown in FIGS.
0 and a drive transmission system for moving the pushing plate 55. These transmission systems are all provided on the frame on the back side of the folding unit frame 49 shown in FIG.

The drive system for the upper roller 51 and the lower roller 52 shown in FIGS. 8 and 9 is driven by a forward / reverse transport motor 162 provided on the sheet post-processing apparatus 2 side.
The signal is input to the gear pulley 129 on the folding unit 50 side via the gates 7 and 128. Since the one-way clutch 123 is interposed between the gear pulley 129 and the shaft 113 for driving the upper roller moving cam 68, the gear pulley 129
Only in one direction (rotation in the direction opposite to the arrow in FIG. 8), the upper roller moving cam 68 rotates, and the upper roller 51 moves vertically. Drive from the gear pulley 129 is transmitted to the bundle transport upper roller shaft 101 and the lower roller shaft 103 by pulleys 130 and 131 via a timing belt 135. The pulleys 130, 131 and the shafts 101, 1
03, one-way clutches 124 and 125 are interposed, and pulleys 130 and 131 (in the direction of the arrow in FIG. 8).
, The shafts 101 and 103 are driven to rotate.

Further, a timing belt 135 is stretched so as to rotationally drive the bundle discharge roller pair 60a, 60b via the idle pulleys 132, 133.

When the gear pulley 129 shown in FIG. 8 rotates in the direction of the arrow, the upper bundle transport roller 51 and the lower bundle transport roller 52 rotate in the direction of transporting the sheet bundle into the folding unit 50. When the gear pulley 129 rotates in the direction opposite to the illustrated arrow, the upper roller moving cam 68 rotates as described above,
The upper bundle transfer roller 51 is separated from or pressed against the lower bundle transfer roller 52. Although these operations are not shown,
The flag projection provided on the shaft 113 is detected and controlled by a sensor or the like.

FIG. 10 is a view showing a drive transmission system of the pair of folding rollers 57a and 57b, which is attached to a frame on the back side of the drive system shown in FIGS.

Staples from the sheet post-processing device 2 side
The drive of the folding motor 170 (see FIG. 16) is received by the coupling device 137. Although not shown, the stapling / folding motor 170 drives the coupling device 44 of the stapler unit in FIG. 4 in the forward rotation, and rotates the coupling device 137 in the reverse rotation.

The driving force from the coupling device 137 is
The gear 138 provided on the coaxial 61 is transmitted to the gear 139 rotating the folding roller 57a (see FIG. 7) and also transmitted to the gear 142. The gear 142 is transmitted by a gear 141 to a shaft 111 that drives a cam plate 114 that operates an operation arm 115 that moves the thrust plate 55. Although not shown, the position of the cam plate 114 can be determined by detecting a flag protrusion fixed to the shaft 111 with a sensor.

Next, referring to FIG.
The folding operation of the sheet will be described.

In order to perform stapling (saddle stitching) at the approximate center of the sheet bundle in the processing tray 8 in the conveying direction, the sheet is conveyed in a state where the upper roller 51 and the lower roller 52 are separated. . Thereafter, the leading end of the sheet bundle is detected, and the binding process is performed when the center of the sheet bundle in the transport direction is determined. Thereafter, the upper roller moving cam 68 (see FIG. 6)
To rotate the bundle transport lower roller 52 to the bundle transport upper roller 51.
And the upper bundle transport roller 51 and the lower bundle transport roller 52 until the center in the sheet transport direction is directly below the pushing plate 55.
Is driven to convey the sheet bundle. At this time, since the backup guides 59a and 59b are located at positions covering the peripheral surface of the folding roller and back up (support) the lower surface of the sheet, the sheet bundle is smoothly conveyed. When the approximate center of the sheet bundle in the conveyance direction reaches directly below the pushing plate 55, the bundle detection sensor 54 detects that fact and stops driving the upper bundle conveyance roller 51 and the lower bundle conveyance roller 52 once. In this state, the sheet bundle is suspended by the upper bundle transfer roller 51 and the lower bundle transfer roller 52 as shown in FIG.

As a result, the sheet bundle is aligned by its own weight. Since the sheet bundle is suspended, a sheet path may be simply provided in a portion downstream of the thrust plate 55 without providing a mechanism such as a sheet stopper. Also, since the portion downstream from the thrust plate 55 is inclined downward, the folding unit 5
0 and the entire sheet post-processing apparatus 2 can be made compact.

When the sheet bundle reaches the state shown in FIG. 11A, the folding roller drive shaft 61 is driven to rotate.
When the folding roller drive shaft 61 rotates, the folding roller pair 57
a and 57b rotate, and the cam plate 114 (see FIG. 7) also rotates to push the thrust plate 55 into the pair of folding rollers 57a and 57b.
Move to nip b. Folding roller pair 57a, 57
b rotates while folding the sheet bundle and discharges it to the bundle stacking tray 80.

The pushing plate 55 has a length (L) of the sheet bundle.
Of the folding roller pair 57 (intermediate portion, L / 2)
a and 57b, the upper roller shaft 101 of the upper bundle transfer roller 51 and the lower roller shaft 1 of the lower bundle transfer roller 52
03 is stopped, but the one-way clutches 124 and 125 (see FIG. 8) are interposed between the upper bundle transfer roller 51 and the lower bundle transfer roller 52 and the shafts 101 and 103. While being folded by the veneer 55,
The upper bundle transfer roller 51 and the lower bundle transfer roller 52 are pulled by the sheet bundle and rotate following the sheet bundle, so that there is no problem in bending the sheet bundle. Therefore, the sheet bundle is smoothly folded by the pair of folding rollers 57a and 57b. Thereafter, the sheet bundle is discharged from the folding unit 50 to the bundle stacking tray 80 from within the folding unit 50 by rotating the bundle transport upper roller 51 and the bundle transport lower roller 52 to rotate the bundle discharge roller pair 60a, 60b.

(Control Block Circuit) FIG. 16 is a schematic block diagram relating to control of the sheet post-processing apparatus 2. The control block 149 includes a central processing unit (CPU) and a ROM, a C, which stores control means executed by the CPU in advance.
It is composed of a RAM or the like for storing the operation data of the PU and the control data received from the main body 1 of the copying machine 20.

The control block 149 includes various 1 /
0 is provided. An arrow pointing toward the control block 149 is defined as an input side, and an arrow pointing away from the control block 149 is defined as an output side.

The circuit relating to the sheet alignment includes a front alignment HP sensor 151 for setting the home position (HP) of the alignment plate 9 for aligning both ends of the sheet with the processing tray 8, and a rear alignment HP sensor 152. . Matching plate 9, 9
2 (see FIG. 2), it waits at the positions of the front alignment HP sensor 151 and the back alignment HP sensor 152 until the first sheet is carried into the processing tray 8. Alignment motor 1 on the front side
Reference numeral 4 denotes a pulse motor for moving the near-side matching plate 9, and a far-side matching motor 14 is a pulse motor for moving the far-side matching plate 9. The alignment plate 9 is moved by the respective alignment motors 14 so that width alignment according to the width of the sheet bundle can be performed. Further, the alignment plate 9 can be freely shifted (job) in a direction intersecting the transport direction for each sheet bundle for each sheet bundle.

Next, a circuit related to the lifting tray 90 is as follows.
A paper surface sensor 93 for detecting the uppermost surface of the sheet on the elevating tray 90, an elevating clock sensor 150 for detecting the amount of rotation of the elevating tray motor 155 by an encoder, and an upper limit switch 153 for restricting an elevating movement range of the elevating tray 90.
And a lower limit switch 154. This circuit is
The lift tray motor 155 is controlled by the input signals of the sensors 93 and 150 and the switches 153 and 154 to drive the lift tray 90.

A circuit related to detecting whether or not a sheet or a sheet bundle is loaded in the elevating tray 90 and the folded sheet discharge stacker 80 includes an elevating tray for detecting the presence or absence of the elevating tray 90. Paper sensor 156
And a detection sensor in the folded sheet discharge stacker 80. A folded sheet stacker paper sensor 157 is provided. These sensors 156 and 157 are also used as sensors that warn the operator when sheets are left before the sheet post-processing apparatus is activated or when the sheet bundle is not removed after a predetermined time has elapsed.

A circuit related to door opening / closing device detection for detecting whether the door of the sheet post-processing device 2 is opened and whether the main body 2 of the sheet post-processing device is properly mounted on the main body 1 of the image forming apparatus 20 is as follows. Front door sensor 158 and copier body 1
And a joint switch 159 for detecting whether or not the sheet post-processing 2 is correctly mounted.

The circuits related to the sheet conveying operation and the sheet bundle conveying operation in a state where the sheets are stacked are: on the conveying guide 3 that the sheet has been conveyed from the main body 1 of the copying machine 20 to the sheet post-processing apparatus 2. Sheet detection sensor 4 to detect
A processing tray sheet detection sensor 160 for detecting the presence or absence of a sheet on the processing tray 8, a position where the staple is driven into the center of the sheet conveyed from the processing tray 8 in the conveyance direction, and a position where the staple is driven. In order to determine the position at which the sheet is to be folded at the same position, the central binding position and central binding position sensors 95 and 95 for detecting the leading end of the sheet bundle in the transport direction, and the sheet bundle on the processing tray 8 are transferred to the elevating tray 90 side. An extruding claw sensor 76 for detecting the home position of the extruding claw 13 provided on the transfer belt 12, and a home position at a position where the upper bundle transfer roller 51 at the entrance of the folding unit 50 is separated from the lower bundle transfer roller 52. And an upper roller HP sensor 161 for detecting the position, based on a signal from each sensor. And controls the feed motor 162 and the stepping motor 70. Transport motor 16
The rotational force of No. 2 is transmitted to the transport roller pair 5, the discharge roller pair 6, the upper bundle transport roller 51, the lower bundle transport roller 52, and the pair of bundle discharge rollers 60a and 60b. The upper roller moving cam 68 that moves the bundle conveying roller pair 51 is rotated by the reverse rotation of the conveying motor 162. Stepping motor 70
Of the transfer lower roller 1 disposed on the processing tray 8
8, the upper transport roller 19 and the first pulley 10 for circulating the transfer belt 12.

A circuit related to the control of the paddle 17 includes a paddle HP sensor 163 for detecting the rotational position of the paddle 17.
And a transport HP sensor 164 for detecting a position where the transport upper roller 19 is separated from the transport lower roller 18, and controls the paddle motor 165 based on signals from the sensors 163 and 164. .

The circuits related to the control of the stapling / folding operation include a staple HP sensor 166 for detecting that the driving head unit 31 and the anvil unit 32 in the stapler unit 30 can be driven by a stapler, respectively, and a driving head unit 31. A needle sensor 167 for detecting whether or not a staple is set therein, and for detecting whether or not the driving head unit 31 and the anvil unit 32 are at the initial position (the position in FIG. 4) at the time of shifting in the sheet conveying direction. Staple slide HP sensor 1
68, a staple / folding clock sensor 171 for detecting the rotation direction of a staple / folding motor 170 for switching the driving of the stapler unit 30 and the driving of the folding unit 50 by forward / reverse rotation, and a state in which the stapler unit 30 and the folding unit 50 can be operated. A safety switch 172 for detecting the presence of the staple slide motor 42 and the staple / folding motor 170 is controlled by these sensors and switches.

The stapler slide motor 42 transmits a rotational force to a guide screw shaft 36 that moves the driving head unit 31 and the anvil unit 32 in a direction intersecting the sheet conveying direction. The stapling / folding motor 170 drives the coupling device 44 (see FIG. 4) of the stapler unit 30 by one-way rotation of the forward / reverse drive, and the coupling device 137 (see FIG. 10) of the folding unit 50 by the other rotation. It has become.

Next, the operation of the sheet post-processing apparatus 2 in each processing mode will be described.

The basic processing modes include: (1) non-staple mode: a mode in which sheets are stacked on the elevating tray 90 without binding, and (2) side staple mode: an end (side) in the sheet conveyance direction. And (3) saddle step mode: binding a half position of the sheet length in the sheet conveying direction at a plurality of positions, folding the sheet at the binding position, and binding. And a mode in which the sheets are stacked on the bundle discharge stacker 80.

[(1) Non-staple mode] When this mode is selected, first, the control block 149 drives the stepping motor 70 which circulates the transfer belt 12 to the home position (the HP position in FIG. 3). Is moved to a pre-home position (PreHP position in FIG. 3) which is a sheet stacking reference position on the processing tray 8, and is stopped. At the same time, the transport motor 162 is driven, and the transport roller pair 5 and the discharge roller pair 6 are driven.
To rotate the paper ejection rollers 1a, l of the main body 1 of the copying machine 20.
Wait for the sheet to be discharged from b. When the sheet is discharged, the conveying roller pair 5 and the discharging roller pair 6 convey the sheet to the processing tray 8. The sheet detection sensor 4 detects a sheet and moves the alignment motors 14 and 1 that move the alignment plate 9.
4. Start timing of the paddle motor 165 for rotating the paddle 17 is measured.

The control block 149 controls the alignment motors 14 and 1 while the sheets are discharged onto the processing tray 8 and stacked.
4 and the paddle motor 165 are driven. By this driving, the alignment plates 9 and 9 move in the width direction intersecting with the sheet conveying direction, aligning both ends of the sheet, and the paddle 17
At the reHP position, the sheet is rotated so that the sheet edge portion abuts on the pushing claw 13 and is aligned. This operation is repeated each time a sheet is discharged to the processing tray 8. When a predetermined number of sheets are aligned with the pushing claws 13, the control block 149 controls the conveyance motor 162 and the paddle motor 165.
And the stepping motor 70 for driving the transfer belt 12 is restarted. As a result, the sheet bundle is moved to the elevating tray 90 side (FIG. 1, arrow A direction).
Go to The moved sheet bundle is stacked on the lifting tray 90. With the discharge of the sheet bundle, the control block 149 causes the elevating tray motor 155 to move the elevating tray 90
Is temporarily lowered by a fixed amount in the descending direction, and then driven and stopped in the ascending direction until the paper surface sensor 93 detects the uppermost sheet, and then waits until the next sheet bundle is placed. .

[(2) Side staple mode] When this mode is selected, the control block 149 drives the transport motor 162 to rotate the transport roller pair 5 and the discharge roller pair 6, thereby causing the main body of the copying machine 20 to rotate. The sheets are discharged to the processing tray 8 from 1 and stacked. Also, the control block 149
Indicates that the alignment motors 14, 1
4 and the paddle motor 165 are driven. As a result, the sheet is aligned at both ends in the width direction by the alignment plates 9 and 9, and the sheet end is transferred to the stopper 21 and stopped. This is repeated for a specific number of sheets.

In a state where the sheet bundle is regulated by the stopper 21, the upper conveying roller 19 is moved to the lower conveying roller 18 side, and the upper conveying roller 19 and the lower conveying roller 18 sandwich the sheet bundle. Thereafter, the control block 149 drives and rotates the staple / folding motor 170 in the stapling operation direction to perform the binding process, and
The binding process is performed by the anvil unit 32. In the case where the binding process is performed at a plurality of positions at the sheet end, the binding process is performed after the staple slide motor 42 is driven and moved.

When the binding process is completed, the sheet bundle after the binding process is moved by the stepping motor 70 to the lower conveying roller 18, the upper conveying roller 19, and the transfer belt 12 toward the lifting tray 90 (in the direction of arrow A in FIG. 1). Move.
As a result, the sheet bundle is delivered from the lower conveying roller 18 and the upper conveying roller 19 in the order of the pushing claw 13 and is stacked on the elevating tray 90. Subsequent operations of the elevating tray 90 are the same as those in the non-staple mode described above, and will not be described.

[(3) Saddle Step Mode] In this mode, a binding process and a folding process are performed at a position substantially at the center of the sheet length in the sheet conveying direction. The operation of stacking the sheets discharged from the image forming apparatus 1 on the processing tray 8 is the same as in the side staple mode described above, and the description of the operation will be omitted.

After the sheets are aligned and stacked on the processing tray 8, the upper transport roller 19 is lowered to the lower transport roller 18 side.
The sheet bundle is sandwiched between the upper conveying roller 19 and the lower conveying roller 18. Next, in order to retract the stopper 21 from the sheet bundle conveying path and transfer the sheet bundle in the direction of arrow B in FIG.
The control block 149 controls the staple slide motor 42
Drive. By this drive, as shown in FIGS. 4 and 5, the stopper engaging projection 24 of the driving head unit 31 is moved.
The stopper 21 retreats from the moving area of the driving head unit 31 and the anvil unit 32 by engaging with the moving arm 23. Driving head unit 31,
The anvil unit 32 is stopped at a driving setting position in a direction supporting the sheet moving direction. Subsequently, the control block 149 rotates the stepping motor 70 in a direction opposite to the non-staple mode or the side staple mode. By this driving, the sheet bundle is moved up and down the tray 90.
Is transferred in the opposite direction (the direction of arrow B in FIG. 1). By this transfer, the bundle detection sensor 5 in the folding unit 50 is
When 4 detects the leading end of the sheet bundle in the conveying direction, the upper conveying roller 19 and the lower conveying roller 18 coincide with the binding position at a substantially central portion in the sheet conveying direction based on the sheet length information sent in advance in the conveying direction. Then, the sheet bundle is conveyed to the point where it is stopped.

When the stepping motor 70 rotates in the reverse direction, the first pulley 1
0 between the first pulley shaft 10a and the one-way clutch 7
5, the rotational force of the stepping motor 70 is not transmitted, and the transfer belt 12 and the pushing claws 13 remain stopped.

Next, the control block 149 performs the binding process by rotating the staple / folding motor 170 for driving the head drive shaft 38 and the anvil drive shaft 37 in the direction in which they are operated. When binding a plurality of positions, the stapler slide motor 42 is driven to rotate the screw shaft 3
After the sheet is moved to a predetermined position in the direction intersecting with the sheet conveying direction by the rotation of 5, 36, the binding process is performed.

When a sheet bundle is conveyed to the binding processing position, the position of the sheet bundle on the leading end side in the conveying direction is:
It is already at a position where it has passed the lower bundle transport roller 52 in the folding unit 50 and the upper bundle transport roller 51 that is separated therefrom.

After the binding process is completed, to perform the folding process,
First, the transport motor 162 shown in FIG. 8 is reversed to rotate the upper roller moving cam 68 shown in FIGS. Due to this rotation, the bearing holder 102 moves to lower the bundle transport upper roller 51 toward the bundle transport lower roller 52, so that the sheet bundle is sandwiched by the tension spring 104.

Next, the upper transfer roller 19 in the processing tray 8
Is lifted from the sheet bundle to release the nipping of the sheet bundle.
This time, the upper and lower bundle transport rollers 51 and 52 are driven by the transport motor 162 to transport the sheet bundle further downstream. At the time of this conveyance, the conveyance motor 162 is stopped while decelerating from the signal of the bundle detection sensor 54 and the sheet length information so that the substantially central portion in the conveyance direction of the sheet bundle, that is, the binding position is the folding position. The sheet bundle is sandwiched between the upper bundle transport roller 51 and the lower bundle transport roller 52 and is suspended in the transport path.

When the staple / folding motor 170 is driven in the direction opposite to the binding process, as shown in FIG. 7B, the folding roller pairs 57a and 57b rotate in the direction to sandwich the sheet bundle and the pushing plate 55. Descends. At the same time, the backup guides 59a, 59b also move to open the folding roller peripheral surface on the sheet bundle side. Veneer 5
After the sheet bundle 5 has been moved to sandwich the sheet bundle between the rotating folding roller pairs 57a and 57b, the sheet bundle is moved to the folding roller pair 57a.
a, 57b. Subsequently, the pushing plate 55 moves in a direction away from the sheet bundle, and the sheet bundle is further folded by the pair of folding rollers 57a and 57b.
At this stage, the upper bundle transfer roller 51 and the lower bundle transfer roller 5
2. The pair of bundle discharge rollers 60a and 60b
And rotates in a direction in which the sheet bundle can be discharged to the bundle stacking tray 80. On the other hand, the folding roller pair 57a, 57b
6 rises and stops when it is detected by the butting plate Hp sensor 169. The sheet conveyed between the bundle discharge roller pair 60a, 60b is discharged to the bundle stacking tray 80 and stacked. The folded sheet bundle is held down by the folded sheet presser 81 so as not to be opened, so that the loading of the next folded sheet bundle is not hindered.

When the time during which a bundle of sheets can be discharged by the bundle discharge rollers 60a and 60b has elapsed, the upper bundle transfer roller 51 separates from the lower bundle transfer roller 52, moves upward, and moves to the next position. In preparation for loading a sheet bundle.

(Characteristic Features of the Present Invention) As described above, the folded sheet stacking device 79 of the present invention is formed on the bottom 80a of the bundle stacking tray (discharge tray) 80 in FIGS. With the concave portion 82 absorbing the bulge on the folding side of the sheet bundle and the rotating shaft 83a provided near the exit of the bundle stacking tray 80 as a fulcrum, it can be tilted in the direction of arrow H by being urged almost vertically by a spring 84. A bundle stopper (stopper member) 83 and the like are provided.

The sheet bundle P discharged by the pair of bundle discharge rollers 60a and 60b is, as shown in FIG.
Is folded into the concave portion 82 to reduce the difference in thickness between the bulged portion Pa and the open end Pb. As a result, the folded sheet stacking device 79 can stack the sheet bundle in a stable state, and can improve stackability.

When the sheet bundles are sequentially stacked in the bundle stacking tray 80, as shown in FIG. 14, the sheet bundle moves in the sheet bundle discharge direction (left direction in the figure) due to the contact resistance between the sheet bundles, and the bundle stopper 83 is pushed by the sheet bundle and the spring 84
Open outwards against As a result, the bulging portion Pa of the sheet bundle shifts outward, so that the difference in thickness between the bulging portion Pa and the open end Pb is reduced. In addition, the folded sheet stacking device 79 can reduce the stacking height of the entire sheet bundle and stack the sheet bundle in a stable state. Moreover,
The bulging portion Pa of the stacked sheet bundle abuts against the bundle stopper 83, and the amount of movement is restricted, and the inclined bundle stopper 8 is tilted.
3, unlike the conventional discharge tray 86 shown in FIG. 19, the amount of movement of the sheet bundle is small, and the stacking space of the sheet bundle can be narrowed accordingly. In addition, since the sheet bundle moves, the newly discharged sheet does not cause the open end Pb of the already stacked sheet bundle to be turned over, and the sheet bundle may be wrinkled or bent. Nothing.

Although the bundle stopper 83 is inclined, as shown in FIG. 15, a bundle stopper (stopper member) 89 that linearly moves on a guide rail 89a against a tension spring 88. There may be. In this case, the same advantage as that obtained when the tilting bundle stopper 83 is used is obtained.

Further, since the bundle stoppers 83 and 89 are tilted or moved, they do not become an obstacle when taking out the sheet bundle.

Further, the initial position of the bundle stoppers 83 and 89 is set to a position for receiving a folded sheet of the maximum size. With this setting, any size of folded sheet does not protrude from the bundle stacking tray 80 and is stacked in a folded state.

Although the saddle stitch mode of the present embodiment has been described in which the binding process and the folding process are performed in a series, it is needless to say that the saddle stitch mode can also be adopted when only the folding process is performed without performing the binding process. It goes without saying that the folded sheet stacking apparatus can stack a sheet bundle that has not been bound and is only folded.

[0117]

According to the sheet stacking device of the present invention, since the concave portion is formed in the discharge tray, the difference in thickness between the expanded portion of the folded sheet and the open end of the folded sheet is reduced, and only one side is raised. Further, the stacked stacked sheets can be stacked on the discharge tray in a substantially horizontal and stable state.

When the discharge tray is provided with a stopper member that can be displaced to the downstream side in the folded sheet transport direction, the folded sheet loaded first is moved downstream by the folded sheet loaded later. When the stopper member receives the moved folded sheet, the stopper member is displaced to the downstream side in the folded sheet discharging direction, and the folded sheets are not overlapped with each other in the up-down direction in the folded sheet discharging direction. Since the sheets are stacked with their positions slightly shifted to the sides, the folded sheets can be stacked on the discharge tray in a substantially horizontal and stable state. Further, since the folded sheets can be supported with a slight shift in the folded sheet discharging direction, the space for stacking the folded sheets can be reduced.

When the position of the stopper member is set to a position for receiving the maximum size of the folded sheet, any size of the folded sheet is protruded from the discharge tray and stacked in a turned up state. There is no such thing.

Since the image forming apparatus of the present invention is provided with the above-described sheet stacking apparatus having excellent stacking properties, the number of sheets on which an image can be formed on a sheet can be increased at one time. Efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a sheet post-processing apparatus provided with a folded sheet stacking apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a processing tray portion of the sheet post-processing apparatus as viewed from above.

FIG. 3 is an enlarged view of a transfer belt portion of the sheet post-processing apparatus.

FIG. 4 is a diagram of the stapler unit of the sheet post-processing apparatus as viewed from a sheet conveying direction.

FIG. 5 is an explanatory view of an operation of a stopper of the sheet post-processing apparatus.

FIG. 6 is a front view of a frame of a folding unit of the sheet post-processing apparatus.

FIG. 7 is a diagram illustrating the operation of a folding unit of the sheet post-processing apparatus. (A) is a state diagram before sheet bending.
(B) It is a state figure during sheet bending.

FIG. 8 is a diagram illustrating a folding unit driving mechanism of the sheet post-processing apparatus.

FIG. 9 is a diagram illustrating a driving mechanism of a folding unit of the sheet post-processing apparatus.

FIG. 10 is a diagram of a driving mechanism of a folding unit of the sheet post-processing apparatus.

FIG. 11 is an explanatory view of a sheet bundle folding operation by a pushing plate of a folding unit of the sheet post-processing apparatus. (A) is a state diagram before sheet bending. (B) It is a state figure during sheet bending.

FIG. 12 is a front sectional view of the folded sheet stacking apparatus according to the embodiment of the present invention.

13 is a diagram illustrating a stacked state of the sheet bundle when the number of folded sheet bundles is small in the folded sheet stacking device of FIG. 12;

14 is a diagram illustrating a stacked state of the sheet bundle when the number of folded sheet bundles is large in the folded sheet stacking device of FIG. 12;

FIG. 15 is a front sectional view of a sheet stacking apparatus according to another embodiment of the present invention.

FIG. 16 is a schematic control block diagram of a sheet post-processing apparatus.

FIG. 17 is a schematic front sectional view of a copying machine provided with a folded sheet stacking device in a main body.

FIG. 18 is a schematic front view of a conventional folded sheet stacking device.

FIG. 19 is a schematic front view of a conventional folded sheet stacking device. (A) is a state diagram when the number of stacked folded sheets is small. (B) is a state diagram when the number of stacked folded sheets is large.

[Explanation of symbols]

P Sheet, sheet bundle Pa Folded sheet or bulging portion on the folding side of sheet bundle Pb Open end of folded sheet or sheet bundle 1 Main body of copying machine (image forming apparatus) 2 Sheet post-processing apparatus 20 Copy machine (image 21 Forming device 21 Stopper 30 Stapler unit (Sheet binding device) 31 Driving head unit 32 Anvil unit 50 Folding unit (Sheet folding device) 60 Bundle discharge roller 60a Roller, bundle discharge roller pair 60b Followed roller, bundle discharge roller pair 79 folding Sheet stacking device 80 Bundle stacking tray (discharge tray) 80a Bottom part 81 Folded sheet holder 82 Depression 83 Bundle stopper (stopper member) 83a Bundle stopper fulcrum 84 Spring 88 Tension spring 89 Bundle stopper (stopper member) 89a Guide rail 149 Control block 902 Image Forming part ( Image forming means)

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kenichi Matsuno 430-1 Kobayashi, Masuho-cho, Minamikoma-gun, Yamanashi Prefecture F-term (reference) 3F054 AA05 AC02 AC03 AC05 BA03 BG02 BG07 BG11 DA01 3F108 GA02 GA03 GA04 GB01 GB03 HA02 HA39

Claims (5)

[Claims] 1. A discharge tray having a concave portion for receiving the end portion of a folded sheet discharged first with the folded end portion formed at a downstream end in the discharge direction of the folded sheet is provided. Folded sheet loading device. 2. A stopper member is provided at the downstream end of the discharge tray, the stopper member being capable of receiving the end of the folded sheet and being displaced downstream in the discharge direction of the folded sheet. The folded sheet stacking device according to claim 1. 3. The folded sheet stacking device according to claim 2, wherein an initial position of the stopper member is set to a position for receiving a folded sheet of a maximum size. 4. An image forming means for forming an image on a sheet, a sheet folding apparatus for folding a sheet on which an image is formed by the image forming means to create a folded sheet, and a folded sheet created by the sheet folding apparatus An image forming apparatus comprising: the folded sheet stacking device according to claim 1, wherein the folded sheet stacking device receives the folded sheet. 5. An image forming unit that forms an image on a sheet, a sheet bundle binding device that binds the sheets on which the image is formed by the image forming unit in a bundle, and a sheet bundle that is bound by the sheet bundle binding device. And a folding sheet stacking device according to claim 1 or 2, which receives the folded sheet bundle created by the sheet folding device. Image forming apparatus.