JPH10139266A - Sheet processing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry a sheet bundle in an always right condition regardless of the size and strength of firmness by carrying it without curving the sheet bundle when a width directional length orthogonal to the carrying direction of the sheet bundle is shorter than a prescribed length, and carrying it while curving the sheet bundle in the width direction when it is long. SOLUTION: Rollers 30b and 30c as first carrier rollers have the same outside diameter, and rollers 30a and 30d as second carrier rollers arranged in the vicinity of a lengthwise directional end part have the same outside diameter, and the outside diameter of the rollers 30a and 30d is larger than the outside diameter of the rollers 30b and 30c. A discharge roller 31 is opposed only to the rollers 30b and 30c. An interval between the rollers 30a and 30d is wider than a prescribed width X, and a sheet bundle having a width smaller than the prescribed width X is sandwiched and carried (b) only by the rollers 30b and 30c and the discharge roller 31. On the other hand, a sheet bundle having a width larger than the prescribed width X is carried (a) by the rollers 30a and 30d while being sandwiched and carried by the rollers 30b and 30c and the discharge roller 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet processing apparatus, and more particularly, to a sheet processing apparatus, for example, which sequentially prints sheets such as copy sheets discharged from an image forming apparatus such as a copying machine, a printing machine, a laser beam printer, etc. The present invention relates to a sheet processing apparatus that takes in the apparatus, performs processing such as alignment of the sheet, binding and folding near a substantially center of the sheet, and discharges and stacks the sheet to a stacking unit.

[0002]

2. Description of the Related Art As shown in FIG. 16, a conventional sheet processing apparatus 300 includes conveying rollers 301 and 302, a sheet stopper 303, and the like.
, Sheet aligning means 304, sheet binding device 305, protrusion plate 306, folding rollers 307, 308, discharge rollers 309, 31
0 and a loading tray 311.

In a conventional sheet processing apparatus 300, a sheet discharged from an image forming apparatus (not shown) is conveyed into the sheet processing apparatus 300. The sheet is first transported by rollers
The sheet is nipped and conveyed by 301, and is passed to a conveying roller 302 through the vicinity of a sheet binding device 305. Further, the sheet is
The sheet is conveyed until the leading end reaches the sheet stopper 303 waiting at the first stacking position, and the ends are aligned by the sheet aligning means 304 to perform alignment. This similar operation is repeated for a plurality of sheets, and a plurality of sheets are stacked at the first stacking position. The stacked sheets are bound and bound by the sheet binding device 305. After that, sheet stopper 30
3 moves to a second loading position (the position shown in FIG. 16) above the first loading position. Then, the bundle of bound sheets enters the folding rollers 307 and 308 by being protruded by the protruding plate 306, is folded in two, and is discharged onto the stacking tray 311 by the discharge rollers 309 and 310. At this time, as shown in FIG. 17, the discharge roller 309 has four rollers 309a, 309b, 309c, 309d of the same size.
Therefore, a small-sized sheet bundle considered to be relatively strong and a large-sized sheet bundle considered to be relatively weak are also conveyed.

[0004]

However, in the above-mentioned conventional example, when a sheet bundle with a low stiffness is conveyed,
Immediately after the leading end of the sheet bundle passes through the discharge rollers 309 and 310, the sheet bundle faces downward and collides with the stacking tray 311 at an angle close to a right angle in such a way that the sheet bundle falls down. There was a possibility that it would not be done.

Therefore, when discharging the sheet bundle onto the stacking tray 311, the sheet bundle is bent in a width direction perpendicular to the conveying direction regardless of the size and the stiffness of the sheet bundle. It is conceivable to convey while stiffening. However, in a sheet bundle having a small width and strong stiffness, a vertical direction (a direction parallel to the conveying direction) is used.
However, there is a possibility that it will be broken in the vertical direction if an attempt is made to add a vertical stiffness.

When the sheet bundle with the vertical fold is discharged onto the stacking tray 311, the folding rollers 307 and 308 are folded.
As a result, the folded fold may be opened immediately, and the stacking tray 311 may not be correctly loaded.

SUMMARY OF THE INVENTION It is an object of the present invention to always discharge a sheet bundle to a stacking tray in a correct state regardless of the size and the strength of the sheet and to stack the sheet bundle.

[0008]

To achieve the above object, a typical configuration of the present invention comprises a first sheet stacking section capable of stacking a plurality of sheets, and a sheet stacking section on the first sheet stacking section. Sheet conveying means for conveying the sheets, aligning means for aligning the sheets stacked on the first sheet stacking section, and binding of the aligned plurality of sheets at a substantially central portion in the conveying direction of the first sheet conveying means. Sheet binding means for stopping,
Sheet bundle folding means for folding the bound sheet bundle into two at the binding stop position, a second sheet stacking unit for stacking the folded sheet bundle, and a sheet folded in the second sheet stacking unit Second sheet conveying means for conveying the bundle,
When the sheet bundle is conveyed to the second sheet stacking unit, the sheet bundle is not bent when the length in the width direction orthogonal to the conveying direction of the sheet bundle is shorter than a predetermined length. When the length of the sheet bundle in the width direction is longer than a predetermined length, the sheet bundle is conveyed while being curved in the width direction.

According to the above configuration, when the sheet bundle is conveyed to the second sheet stacking section, the sheet bundle is bent in the width direction if the length of the sheet bundle in the width direction is longer than a predetermined length.
Since the sheet bundle is conveyed with a so-called vertical stiffness, the leading end of the sheet bundle does not drop vertically in the second sheet stacking portion during the conveyance, and the stacking does not become defective. On the other hand, if the length of the sheet bundle in the width direction is shorter than the predetermined length, the sheet bundle is conveyed without bending, so-called vertical stiffness. Can be prevented. Accordingly, the sheet bundle conveyed to the second sheet stacking section is always conveyed and stacked in a correct state regardless of the size and the strength of the sheet.

[0010]

Next, an embodiment of a sheet processing apparatus to which the present invention is applied will be specifically described with reference to the drawings. FIG. 15 is a vertical sectional front view showing an example of an image forming apparatus provided with the sheet processing apparatus according to the present embodiment.

In the order of the following description, first, the schematic structure of an image forming apparatus (a copying machine is exemplified in the present embodiment) will be briefly described, and then the sheet processing apparatus according to the present embodiment will be described in detail. I do.

{Schematic Configuration of Image Forming Apparatus} First, the schematic configuration of the image forming apparatus will be briefly described with reference to FIG. As shown in FIG. 15, the image forming apparatus main body 900 is provided with a platen glass 906 as a document table, a light source 907, a lens system 908, a paper feeding unit 909, an image forming unit 902, and the like.

The paper feeding section 909 has cassettes 910 and 911 detachably mounted on the apparatus main body 900 for storing sheets S for recording and a deck 913 arranged on a pedestal 912. The image forming unit 902 includes a cylindrical photosensitive drum 914 and a developing device 915 around the photosensitive drum 914, a transfer charger 916, and 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 transport device 92 is provided.
0, a fixing device 904, a discharge roller pair 905, and the like.

Next, the operation of the image forming apparatus main body 900 will be described. Control device 15 provided on the device main body 900 side
When a sheet feed signal is output from 0, the sheet S is fed from the cassettes 910 and 911 or the deck 913. On the other hand, light reflected from a light source 907 on a document D placed on a platen glass 906 serving as a document placing table is reflected by a lens system.
Irradiated on the photosensitive drum 914 via 908. The photoreceptor drum 914 is charged in advance by a primary charger 919, and is irradiated with light to form an electrostatic latent image.
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 sent to the image forming unit 902 after the skew of the sheet S is corrected by registration rollers 901 and the timing is further adjusted. Image forming unit 902
Then, the toner image on the photosensitive drum 914 is transferred to the fed sheet S by the transfer charger 916. The sheet S to which the toner image has been transferred is charged by the separation charger 917 to a polarity opposite to that of the transfer charger 916, and
Separated from 4

Then, the separated sheet S is transported by a conveying device.
920 to the fixing device 904,
Thereby, the transfer image (toner image) is permanently fixed on the sheet S. The sheet S on which the image has been fixed is discharged from the apparatus main body 900 by a discharge roller pair 905.

After the image is formed on the sheet S fed from the sheet feeding unit 909, the image forming apparatus main body is
The sheet is discharged from the printer 900 and is carried into a sheet processing apparatus 2 described later.

{Structure of Sheet Processing Apparatus} Next, the sheet processing apparatus according to the present embodiment will be described in detail. FIG. 1 is a vertical sectional side view of the sheet processing apparatus according to the present embodiment.
In FIG. 1, reference numeral 900 denotes the image forming apparatus main body described above. In this embodiment, a copying machine is exemplified as an image forming apparatus. However, the present invention is not limited to this. For example, another image forming apparatus such as a printer or a printing apparatus may be used.

Reference numeral 905 denotes a discharge roller pair.
5a and a discharge roller 905b pressed by the discharge roller 905a. Reference numeral 2 denotes a sheet processing apparatus to which the present invention is applied.

Reference numeral 3 denotes an inlet flapper, which is engaged with an inlet solenoid 3d (see FIG. 3), and switches between a bookbinding mode and a stack mode by turning on and off the power of the inlet solenoid 3d. I have.

(Stack mode configuration) 4 is a paper discharge guide. A stacker discharge roller 5 and a stacker discharge roller 6 are arranged downstream of the paper discharge guide 4. Reference numeral 7 denotes a stacker tray on which sheets discharged from the stacker discharge rollers 5 are stacked.

When the stack mode is selected in the sheet processing, an image is formed by the image forming apparatus 900, and the discharged sheet is guided to the paper discharge guide 4 by the entrance flapper 3, and is stacked by the stack discharge roller 5 and the stack discharge roller. The paper 6 is discharged onto the stacker tray 7 and stacked.

(Structure of Bookbinding Mode) Reference numerals 11 and 12 are guides. Reference numeral 13 denotes a conveying roller, and a conveying roller
14 are located. The transport rollers 14 are the transport rollers
13 is pressed.

Reference numeral 15 denotes an upper portion of the switching flapper, and 16 denotes a lower portion of the switching flapper. The upper and lower switching flappers 15 and 16 are engaged with the upper and lower switching solenoids 15d and 16d (see FIG. 3), and are turned on and off by an electric signal to indicate the dashed line and the solid line shown in FIG. It is configured to take two positions.

Reference numerals 17a and 22a denote conveying rollers, respectively. Elastic members 17d and 22d for bringing the sheet into contact with the conveying rollers 17a and 22a are provided on opposing surfaces thereof.
a, 22a. These transport rollers 17a, 22a
Receives the sheet sent by the transport roller 13,
Convey further.

A first sheet transport means for transporting a sheet by the transport rollers 13, the transport rollers 14, and the transport rollers 17a and 22a is provided.

When the leading end of the sheet conveyed by the first sheet carrying means reaches the leading end stopper 23 as the first sheet stacking means, the sensor 33 detects that the leading end of the sheet has reached the leading end stopper 23, The first sheet conveying means stops.

Reference numeral 18 denotes a stapler unit to be described later, which is a sheet binding means for binding a sheet bundle by staples. Two
Reference numerals 0 and 21 are guides arranged downstream of the stapler unit 18.

Reference numerals 24a and 24b denote width-adjusting members, which are alignment means for pressing and aligning the sheet from both sides. 23 is the above-mentioned tip stopper, which is the guides 20, 21.
The first sheet stacking unit receives the leading edge of a sheet that has entered the space. The tip stopper 23 is configured to be movable between the guides 20 and 21 in the direction of the arrow in the figure. Tip stopper
The purpose of 23 is twofold. One is positioning when the sheet is stapled by the stapler unit 18, and the other is positioning for folding described later. On the leading end stopper 23, a leading end stopper sensor 33 for detecting the leading end of the sheet is provided.

Reference numeral 25 denotes a projecting unit, which is retracted below the guides 12 and 21 before folding. 26 and 27 are folding rollers as sheet bundle folding means, which are pressed against each other. 28 is a discharge guide, which is a folding roller
This is for guiding the sheet bundle conveyed while being folded by 26 and 27 between the nip between the discharge roller 30 and the discharge roller 31 as the second sheet conveying means.

Reference numeral 29 denotes a discharge sensor, which includes folding rollers 26 and 27.
This detects the leading end and the trailing end of the sheet bundle conveyed while being folded. Reference numeral 32 denotes a stacking tray serving as a second sheet stacking unit, which stacks and holds the sheet bundle discharged by the discharge roller 30 and the discharge roller 31 on a substantially horizontal stacking surface.

Here, the second sheet conveying means will be described in detail with reference to FIG. The discharge roller 30 is composed of four rollers 30a, 30b, 30c, 30d arranged on the same axis. Of these four rollers, rollers 30b and 30c as first transport rollers disposed near the center of the shaft in the longitudinal direction (width direction orthogonal to the transport direction) have the same outer diameter, and are located near the longitudinal end. The rollers 30a and 30d as the second transport rollers provided have the same outer diameter.
The outer diameter of 30a, 30d is larger than the outer diameter of rollers 30b, 30c. Also, the discharge rollers are only applied to the rollers 30b and 30c.
31 are facing each other. The interval between the rollers 30a and 30d is wider than a predetermined width X, and a sheet bundle having a width smaller than the predetermined width X is nipped and conveyed only by the rollers 30b and 30c and the discharge roller 31 (see FIG. 2 (b)). on the other hand,
The sheet bundle having a width larger than the predetermined width X is
b, 30c and the discharge rollers 31 while the rollers 30
a and 30d (see FIG. 2A). At this time, the rollers 30a and 30d near both ends are connected to the rollers 30b and 30 near the center.
Since the outer diameter is larger than c, the sheet bundle is conveyed with a so-called vertical stiffness in a state where both ends are raised and curved.

As described above, according to the above configuration, when the sheet bundle is conveyed to the stacking tray 32, if the length in the width direction of the sheet bundle is longer than the predetermined length X, the Since the sheet bundle is conveyed with a so-called vertical stiffness while being curved, the leading end of the sheet bundle is
There is no danger of hanging in the vertical direction with respect to 32 and causing defective loading. On the other hand, if the length of the sheet bundle in the width direction is shorter than the predetermined length X, the sheet bundle is conveyed without bending, that is, without a so-called vertical stiffness. Breaking can be prevented. Therefore,
The sheet bundle conveyed to the stacking tray 32 is always conveyed and stacked in a correct state regardless of the size and the strength of the sheet.

A roller as the second transport roller
The coefficient of friction of the members forming 30a, 30d is
The coefficient of friction is smaller than that of the members forming the rollers 30b and 30c as the conveying rollers. When the sheet bundle is conveyed while being nipped between the rollers 30b and 30c and the discharge rollers 31, the sheet bundle slips. Roller marks caused by the above are not attached.

Next, a driving mechanism of the entrance flapper 3, the switching flappers 15, 16 and the transport rollers 13, 17a, 22a will be described with reference to FIG.

(Inlet flapper drive mechanism) Inlet flapper 3
Is configured to be swingable about a central axis 3a. A link 3b is fixed to one end of the central shaft 3a. A spring 3c is engaged with the link 3b, and urges the entrance flapper 3 in one direction. 3d is an inlet solenoid,
It is engaged with one end of the link 3b. Inlet solenoid 3d
When the power supply is turned on, the iron core is sucked and the entrance flapper 3 jumps up (in the position indicated by the one-dot chain line in FIG. 3) to switch to the bookbinding mode. When the power is turned off, the stack mode is set, that is, the entrance flapper 3 is at the lower portion (the position indicated by the solid line in FIG. 3) by the urging force of the spring 3c, and guides the sheet bundle toward the guide 4.

(Conveyance Roller Driving Mechanism) Conveyance Rollers 13, 17
Conveying roller pulleys 13b, 17c, and 22c are fixed on the respective center shafts 13a, 17b, and 22b of a and 22a.
Further, elastic members 17d and 22d for pressing a sheet against the transport rollers 17a and 22a are disposed at positions facing the transport rollers 17a and 22a, respectively (see FIG. 1).

A transport motor 51 has a transport motor pulley 52 fixed to its output shaft. A timing belt 53 is wound around the outer circumferences of the transport motor pulley 52 and the transport roller pulleys 13b and 17c, and a timing belt 54 is wound between the transport roller pulleys 17c and 22c. Accordingly, the rotation of the transport motor 51 is transmitted from the transport motor pulley 52 to the timing belt 53 to rotate the transport roller pulleys 13b and 17c, and further rotate the transport roller pulley 22c via the timing belt 54. Thus, the transport rollers 13, 17a, 22a rotate. At this time, since the transport roller pulleys 17c and 22c rotate synchronously, the transport rollers 17a and 22a also rotate synchronously.

(Switching flapper driving mechanism) Switching flapper 1
Flapper links 15b and 16b are fixed on the respective rotation center shafts 15a and 16a of 5 and 16, respectively. This flapper link 15
b and 16b are connected to switching solenoids 15d and 16d, respectively.
Is engaged. Further, springs 15c and 16c are engaged with the other ends of the flapper links 15b and 16b, respectively, and hold the switching flappers 15 and 16 at the illustrated positions. When the power of the switching flappers 15 and 16 is turned on, the switching solenoid
15d and 16d suck the iron core and switch flappers 15 and 16 are shown in FIG.
Is held at the position indicated by the one-dot chain line.

The switching flappers 15 and 16 are switched according to the sheet size processed by the sheet processing apparatus.
The order in which the stacked / aligned sheet bundles are stacked in the present apparatus is always constant, that is, the sheets stacked later always always overlap the upper left of the sheet bundle.

(Width Shifting Mechanism) Next, the width shifting mechanism as the aligning means will be described with reference to FIG. 4, 24a and 24b are both ends in the width direction orthogonal to the transport direction (FIG. 1).
(Before and after), has a wall surface that is horizontal to the sheet bundle conveyance direction and perpendicular to both sides of the sheet bundle, and forms a rack gear near the center. A pinion gear 24c is engaged with each other's rack gear.
Reference numeral 24d denotes a width shifting motor, and a pinion gear 24c is fixed on the output shaft. The width shifting motor 24d is constituted by a stepping motor. Reference numeral 24e denotes a width-adjusting home sensor, which is constituted by a photo interrupter. The width-adjusting home sensor 24e includes the width-adjusting members 24a, 24
When b is retracted outward by a predetermined amount from the maximum sheet width that can be aligned, it is arranged at a position where a flag formed on a part of the width shifting member 24a is detected.

The drive members 24a and 24b are driven by the driving force of the drive motor 24d transmitted via the pinion gear 24c and the rack gear, and align the sheet carried into the stopper 23.

(Stopper Driving Mechanism) Next, a driving mechanism of the stopper 23 will be described with reference to FIGS. In the figure, reference numeral 23 denotes a stopper which receives the leading end of the sheet which has entered between the guides 20 and 21. A roller 23a is rotatably attached to the stopper 23, and slides in a groove formed in the frame 8. Rack gears 23 e are formed at both ends of the stopper 23. This rack gear
23e are respectively engaged with the pinion gear 23b. A shaft 23c is provided at the center of the pinion gear 23b, and transmits drive to the pinion gear 23b. A stopper gear 23d is fixed to one end of the shaft 23c.

Reference numeral 61 denotes a stopper motor, which is constituted by a stepping motor. A gear 62 is fixed on the output shaft of the stopper motor 61, and the gear 62 is a stopper gear.
It is engaged with 23d. Further, a flag is formed on a part of the stopper 23, and when the stopper 23 reaches the home position, the stopper 23 detects the flag.

A stopper sensor 33 detects the presence or absence of a sheet bundle at the tip of the stopper.

(Stapler Driving Mechanism) Next, a mechanism of a stapler unit as a sheet binding means for binding a sheet with a staple will be described with reference to FIGS. 1, 4, and 13. FIG.

The stapler unit (hereinafter, also referred to as “stapler”) 18 includes a support plate 99 fixed to the frame 8.
Are arranged at symmetrical positions with respect to the center of the sheet bundle aligned by the width shifting members 24a and 24b.

In FIG. 12, the stapler 18 has a rotating shaft 18.
A needle driving portion (hereinafter, referred to as a forming portion) serving as an upper needle driving device supported so as to be swingable about a.
It comprises a drive unit 101 and an anvil part (bend part) 19.

Below the stapler 18, a guide member 10 is provided.
2, 111 and the anvil portion 19 form a paper path for guiding the sheet bundle. The paper path portion is configured such that a guide surface 102a of a guide member 102 for guiding the sheet bundle and a binding surface 103 of an anvil portion 19 for staple binding the guided sheet bundle have an angle γ with each other. I have. The guide member 111 on the upper surface forming the paper path having the angle γ has a cutout hole 111a of a size that does not interfere when the forming portion 101 of the stapler 18 swings.

A staple cartridge 104 is detachably mounted on the forming portion 101, and about 5,000 binding needles 105 connected in a plate shape are loaded in the staple cartridge 104. The plate-shaped binding needle 105 loaded in the staple cartridge 104 is urged downward by a spring 106 provided on the uppermost side of the staple cartridge 104, and is conveyed by a feed roller 107 arranged on the lowermost side. Is provided.

The needle fed by the feed roller 107
Reference numeral 105 denotes the forming unit 101 centered on the rotating shaft 18a in FIG.
By swinging in the direction of arrow a. That is, when the stapler motor 108 is started, the eccentric cam gear 110 rotates through the gear train 109, and the forming portion 101 is moved in the direction of the arrow a in FIG. 13 by the action of the eccentric cam integrally mounted with the eccentric cam gear 110. The sheet bundle is staple-bound by swinging to the (anvil portion 19 side) to perform a needle driving operation (clinching operation) and bending the driven needle 105 at the anvil portion 19 on the lower surface of the sheet bundle.

A flag (not shown) is provided coaxially with the eccentric cam gear 110. By detecting this flag with a stapler sensor (not shown), it is determined whether the stapler 18 is clinching or has finished clinching. Or before clinch start) can be detected.

(Driving Mechanism of Folding Means) Next, the driving mechanism of the sheet bundle folding means for folding the bound sheet bundle into two at the binding stop position will be described in detail with reference to FIGS.

A folding motor 64 has a pulley 65 fixed on its output shaft. Reference numeral 67 denotes an idler gear pulley, which is formed coaxially with two pulley portions and one gear portion. A timing belt 66 is wound between one pulley portion of the idler gear pulley 67 and the pulley 65. 68 and 69 are folding gears fixed to the folding rollers 26 and 27 and engaged with each other. One end of the folding gear 68 is engaged with a gear portion of the idler gear pulley 67.

Reference numeral 25 denotes a protruding unit, which includes a protruding plate 25a, holders 25d and 25b, shafts 25c and 25e, and the like. The protruding plate 25a is provided with holders 25d and 25b.
The shafts 25c and 25e are fixed to the holder 25b. A roller (not shown) is rotatably mounted on the outer periphery of the shafts 25c and 25e, and the roller slides in a groove 8a formed in the frame 8.

Reference numeral 73 denotes a gear, which partially constitutes the shaft 72, and is engaged with the idler gear 75. The idler gear 75 is fixed to a shaft 76, and an electromagnetic clutch (protruding clutch) 74a is disposed on the shaft 76. The transmission of the rotation from the pulley 74 on the electromagnetic clutch 74a to the shaft 76 is as follows.
Power ON / OFF (ON / OF of electromagnetic clutch 74a)
F). A timing belt 70 is wound around the pulley 74. One of the timing belts 70 is wound around the other pulley portion of the idler gear pulley 67.

A flag 81 is fixed on the shaft 73a, and the flag 81 is partially notched. A protruding home sensor 82 is provided at a position where the notch of the flag 81 is detected.

The rotation of the folding motor 64 is transmitted from the pulley 65 to the idler gear pulley 67 via the timing belt 66. The rotation of the idler gear pulley 67 is transmitted from the folding gear 68 to the folding gear 69, and the folding rollers 26 and 27 are driven. On the other hand, the rotation of the idler gear pulley 67 is transmitted to the pulley 74 on the electromagnetic clutch 74a via the timing belt 70. By turning on / off the electromagnetic clutch 74a, the rotation of the pulley 74 is transmitted to the shaft 76, and the idler gear 75
Rotates. Due to this rotational transfer, the gear 73 rotates and the shaft 72 makes a circular motion. One end of a link 71 is fitted to the shaft 72, and the other end of the link 71 is connected to the shaft of the protrusion unit 25.
25c. Therefore, the circular motion of the shaft 72 is transmitted to the shaft 25c of the projecting unit 25 via the link 71,
The shaft 25c makes a linear motion along the groove 8a of the frame 8 fitted with the shaft 25c via a roller (not shown).
That is, the projecting unit 25 slides in the direction of the arrow in FIG.

(Discharge Roller Driving Mechanism) The drive mechanism of the discharge roller 30 will be described with reference to FIG. As shown in FIG. 3, a pulley 30 is attached to a shaft 30e which is the central axis of the discharge roller 30.
f is fixed. Reference numeral 91 denotes a discharge motor, and a pulley 92 is fixed on the output shaft. A timing belt 93 is wound between the pulley 92 and the pulley 30f. Therefore, the rotation of the discharge motor 91 is transmitted from the pulley 92 via the timing belt 93 to the pulley 30f,
The discharge roller 30 is driven via e. The discharge motor 91 is formed of a stepping motor, and the peripheral speed of the discharge roller 30 is set faster than the peripheral speed of the folding rollers 26 and 27. Since the transporting force of the folding rollers 26 and 27 is set higher than the transporting force of the discharge roller pair 30 and 31, the sliding force between the discharge roller pair 30 and 31 while the sheet is being nipped and transported by the folding rollers 26 and 27. Then, when the sheet passes through the folding rollers 26 and 27, it is conveyed by the conveying force of the discharge roller pair 30, 31.

In the vicinity of the longitudinal center of the shaft 30e,
A discharge paddle (not shown) is provided, and a discharge roller 30 is provided.
The discharge paddle also rotates at the same time as rotates so that the sheet is reliably discharged.

(Driving Mechanism of Stacker Discharge Unit) A driving mechanism of the stacker discharge roller 5 will be described with reference to FIG. As shown in FIG. 3, a pulley 98 is fixed on a shaft 5a which is the central axis of the stacker discharge roller 5. Reference numeral 95 denotes a stacker discharge motor, and a pulley 96 is fixed on the output shaft. A timing belt 97 is wound between the pulley 96 and the pulley 98. Therefore, the rotation of the stacker discharge motor 95 is controlled by the timing belt 97
To the pulley 98, and drives the stacker discharge roller 5 via the shaft 5a. The stacker discharge motor 95 is constituted by a stepping motor, and the peripheral speed of the stacker discharge roller 5 is set higher than the peripheral speed of the discharge roller 905a.
The conveying force of the pair of discharge rollers 905a and 905b is set higher than the conveying force of the pair of stacker discharge rollers 5 and 6. Therefore, while the pair of discharge rollers 905a and 905b nip and convey the stacker discharge rollers 905a and 905b. Slip between the discharge rollers 905
After passing through a and 905b, the sheet is conveyed by the conveying force of the pair of stacker discharge rollers 5 and 6.

(Configuration of Control System) The configuration of the control system in the sheet processing apparatus will be briefly described with reference to FIG. In FIG. 7, reference numeral 170 denotes an MPU,
4,83, A, B, 24e, based on a signal from 63,33,82,29,34, via respective drivers D ₁ to D _12, the solenoids 3c, 15d, 16d, each motor 95,51 , 108A, 108B,
24d, 61, 64, 91, etc. are controlled.

(Control Sequence) Next, FIGS. 1 and 8
A control sequence of the sheet processing apparatus will be described with reference to FIGS.

FIGS. 8 to 10 show a main routine. The main routine 900 receives various information from the image forming apparatus main body 900 to which the sheet processing apparatus 2 is connected (mode information indicating whether the bookbinding mode is the stack mode, the sheet length L and the sheet width). After receiving the side information of W, the number information N, and the number information M of copies, and receiving the start signal, the operation of the sheet processing apparatus 2 is started (S20).
1). After checking the mode information (S202), if the mode is not the bookbinding mode, the process jumps to the stack mode routine (S205). In the case of the bookbinding mode, it is checked whether the vertical length L is between the upper limit Lmax and the lower limit Lmin that can be processed by the sheet processing apparatus 2 (S203), and if it is outside this range, the stack mode processing is performed (S205). .

Next, in the same manner, it is checked whether the width W is between the upper limit Wmax and the lower limit Wmin which can be processed by the sheet processing apparatus 2 (S204). If the width W is out of this range, the stack mode processing is performed. (S205). If it is within the above range, the entrance solenoid 3c is turned on to open the path to the bookbinding mode (S207). The conveyance motor 51 is turned on to rotate the rollers (S208).

Next, the control routine of the switching solenoids 15d and 16d for controlling the switching solenoids 15 and 16 is skipped (S209). When the distance P between the width shifting members 24a and 24b is P = W
The number of steps that is + α (where α is the gap between the sheet bundle and the abutting portion of the width shifting member) is sent to the width shifting motor 24d and rotated (S210). The number of steps by which the stopper 23 moves downstream from the staple position 19a of the stapler 18 to the position where l = L / 2 is sent to the stopper motor 61 and rotated. That is, at this time, the center of the sheet is at the same position as the staple position 19a (S211). The number counter CNT1 is set to 0 (S212), and the signal of the entrance sensor 83 is confirmed (S213). If ON, the entrance sensor 83
Is turned off (S214), after a predetermined time t when the leading end of the sheet bundle abuts on the stopper 23, P = W−
β (β is the amount by which the width adjustment members 24a and 24b push the sheet)
The number of steps by which the width adjusting members 24a and 24b move to a certain position is sent, and the width adjusting motor 24d is rotated (S21).
Five).

Subsequently, the width shifting members 24a and 24b are P = W + α
The number of steps corresponding to the movement to a certain position is sent to the width adjustment motor 24d (S216). Increment the number counter CNT1 by 1 (S21
7). It is confirmed whether the number counter CNT1 has reached the desired number N (S218).
Returning to S213, the same processing is performed on the sheet sent from the image forming apparatus main body 900. If the desired number N has been reached, the width adjusting members 24a and 24b are rotated in the direction of moving outward (S219), and the operation is continued until the width adjusting home sensor 24e is turned on (S220). When the width adjustment home sensor 24e is turned on, the width adjustment motor 24d is turned off (S220a).

Next, the sheet bundle is stapled.

First, one of the two staplers 18A and 18B starts stapling by one stapler 18A. The stapler motor 108A is turned on (S221), and when the stapler sensor A detects (S222), the stapler motor 108A is turned off (S223). Below, stapler 18
The same operation is performed for B (S224 to S226), and the stapling operation is completed.

Next, the stopper motor 61 is rotated by a step such that 1 = (L / 2) + C so that the stopper 23 is located downstream of the staple position 19a. Here, C is the distance between the staple position 19a and the folding position. At this time, the center (stapled position) of the sheet bundle is on a line connecting the nip positions of the folding rollers 26 and 27 and the center of the protruding plate 25a (S227). Then, the transport motor 51, the inlet solenoid 3c, and the switching solenoids 15 and 16 are turned off to prepare for the folding operation (S228 to S230).

After confirming that the stopper sensor 33 is ON (S231), the discharge motor 91 is turned ON (S232), and the folding motor 64 is turned ON (S233). Push out clutch 74a to O
When N (S234), the protruding plate 25a starts to protrude,
The sheet bundle is guided to the folding rollers 26 and 27.

The operation is continued until the protrusion home sensor 82 is turned on (S235), and when it is turned on, the protrusion clutch 74a is turned off (S236). A timer is started from the point where the discharge sensor 29 is turned off (S237). After the timer confirms that a sufficient time has passed for the trailing end of the sheet bundle to pass through the discharge roller pair 30, 31, the discharge motor 91 is turned off. (S239). When the discharge sensor 29 is turned off, the speed of the discharge motor 91 is also reduced immediately so that the rear end of the sheet bundle passes through the discharge roller pair 30, 31 at a low speed. The copy counter CNT2 is advanced by 1 (S240). If the copy counter CNT2 has not reached the desired number M, the process returns to S206. If the desired number of copies M has been reached, the operation is terminated (S242).

Next, a control routine of the switching solenoid will be described with reference to FIGS.

Half of the sheet size, ie, L / 2, is the guide.
The length k ₁ and the constant B to the switching flapper 15 along 11 and 12
If it is larger than (k ₁ + B) (S252), the switching solenoids 15d and 16d are kept OFF, and this routine ends. Here, the constant B indicates the position of the rear end of the stacked sheet bundle with the stopper 23 at the proper position. This constant B
Is the amount necessary for the next sheet bundle, which has entered the stacked sheet bundle, to be stacked at the highest position without sneaking into the stacked sheet bundle.

If L / 2 is larger than (k ₁ + B), the value is further compared with L / 2 (k ₂ + B) (S254). Here k ₂ along between k ₁ in the same manner as the guide 11, 12 is a distance to the switching flapper 16. The constant B has the same length as described above. If L / 2 is larger than k ₂ + B (S25
4), the upper switching solenoid 15d is turned on (S255), and the sheet bundle is guided by the lower switching flapper 16. L / 2 is (k ₂ +
If it is smaller than B), both the upper switching solenoid 15d and the lower switching solenoid 16d are turned on (S257), and the stacking is performed along the guide 11. Thus, the control routine of the switching solenoid is completed.

Next, the stack mode routine will be described.
This is described using 11.

The number counter CNT is set to 0 (S2
72).

The stack discharge motor 85 is turned on (S27).
3) The stack discharge roller 5 is rotated. It is confirmed whether the stack sensor 84 is ON (S275), and if it is ON, it is further confirmed that the stack sensor 84 is OFF (S275). O
When it becomes FF, 1 is added to the number counter CNT (S27).
6) It is checked whether the number counter CNT matches the number N (S277). If the number counter CNT is smaller than N,
Return to before S274. When the number of sheets on the sheet counter CNT reaches N, the stack discharge motor 85 is turned off after a lapse of time sufficient for the trailing end of the sheet bundle to pass through the stack sensor 84 (S278). Thus, the stack mode routine ends (S279).

In the embodiment described above, a copying machine is exemplified as an image forming apparatus. However, the present invention is not limited to this, and other image forming apparatuses such as a printer and a printing machine may be used.

Further, the route and configuration up to the post-processing discharge roller are not limited to those in the above-described embodiment. For example, a stitcher may be used instead of the stapler as the sheet bundle binding means. Furthermore, the number of staplers used is not limited to two, and one or three or more staplers may be used, for example.

Further, a configuration in which a number of transport rollers and folding rollers are used to perform reliable transport and folding may be employed.

In the above-described embodiment, the discharge roller 30
Has exemplified a configuration in which four rollers are divided and arranged coaxially, but the present invention is not limited to this. For example, two rollers near the center of the same size may be integrated into three rollers. However, it may be divided and used more. Further, in the above-described embodiment, the roller near the width direction end has a larger outer diameter than the roller near the center, but the roller near the width direction end has a smaller outside diameter than the roller near the center. The same effect can be obtained. Further, in the above-described embodiment, the configuration in which two types of rollers (the rollers 30b and 30c and the rollers 30a and 30d) having different outer diameters are illustrated as the second sheet conveying means is not limited thereto. For example, a configuration having third and fourth rollers having different outer diameters as necessary may be employed.

In the above-described embodiment, the configuration in which the outer diameter of the discharge roller is changed to stiffen the sheet bundle is exemplified. However, the present invention is not limited to this. For example, as shown in FIG. A discharge roller 30 and a rib 30 having the same outer diameter.
g may be used to make the sheet bundle stiff. The outer diameter of the discharge roller 30 is the same, and the discharge roller 31 is in contact with the opposite position. Then, on the same axis as the discharge roller 30, near the widthwise end, the discharge roller pair 30,
A protruding rib 30g is provided at a position higher (see FIG. 14A) or a lower position (see FIG. 14B) than the nip position 31. With this configuration, the sheet bundle having a width larger than the predetermined width is nipped and conveyed by the pair of discharge rollers 30 and 31 while the vicinity of the end is lifted by the rib 30g to convey the sheet bundle with a vertical stiffness. Thus, the same effect as in the above-described embodiment can be obtained. Further, according to this configuration, the discharge roller can be formed by one kind of roller, so that a cheaper roller can be formed.

[0084]

As described above, according to the present invention,
When the sheet bundle is conveyed to the second sheet stacking portion, if the length in the width direction of the sheet bundle is longer than a predetermined length, the sheet bundle is conveyed with a so-called vertical stiffness while bending in the width direction. In addition, it is possible to prevent the leading end of the sheet bundle from hanging vertically in the second sheet stacking section during the conveyance and causing a stacking failure. On the other hand, if the length of the sheet bundle in the width direction is shorter than the predetermined length, the sheet bundle is conveyed without bending, so-called vertical stiffness. Can be prevented. Therefore, the sheet bundle conveyed to the second sheet stacking unit is
Regardless of size or stiffness, they are always transported and loaded in the correct state.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a sheet processing apparatus according to the present invention.

FIG. 2 is a front view of a discharge roller pair of the sheet processing apparatus as viewed from a discharge port.

FIG. 3 is an explanatory diagram illustrating a configuration of a transport mechanism of the sheet processing apparatus.

FIG. 4 is a front view illustrating a configuration of a width shifting mechanism and a stopper of the sheet processing apparatus.

FIG. 5 is a vertical sectional side view of a protruding portion and a folding roller portion of the sheet processing apparatus.

FIG. 6 is a plan view of a protruding portion and a folding roller portion of the sheet processing apparatus.

FIG. 7 is a block diagram of a control system in the sheet processing apparatus.

FIG. 8 is a flowchart showing a main routine by the control system.

FIG. 9 is a flowchart showing a main routine by the control system.

FIG. 10 is a flowchart illustrating a control routine of a switching solenoid.

FIG. 11 is a flowchart illustrating a control routine in a stack mode.

FIG. 12 is a main dimension view of the sheet processing apparatus.

FIG. 13 is a sectional view of a stapler unit of the sheet processing apparatus.

FIG. 14 is a front view of a discharge roller pair according to another embodiment as viewed from a discharge port.

FIG. 15 is a vertical cross-sectional front view illustrating an example of an image forming apparatus including the sheet processing apparatus.

FIG. 16 is a vertical sectional side view of a conventional sheet processing apparatus.

FIG. 17 is a front view as viewed from a discharge port of a conventional sheet processing apparatus.

[Explanation of symbols]

 D ... Document S ... Sheet 2 ... Sheet processing device 3 ... Inlet flapper 3a ... Center shaft 3b ... Link 3c ... Spring 3d ... Inlet solenoid 4 ... Discharge guide 5 ... Stacker discharge roller 5a ... Shaft 6 ... Stacker discharge roller 7 ... Stacker Tray 8 Frame 8a Grooves 11, 12, 20, 21 Guides 13, 17a, 22a Transport rollers 13a, 17b, 22b Center shafts 13b, 17c, 22c Transport roller pulley 14 Transport rollers 15 Switching flapper upper 16 ... under switching flapper 15a, 16a ... rotation center shaft 15b, 16b ... flapper link 15c, 16c ... spring 15d ... over switching solenoid 16d ... under switching solenoid 17d, 22d ... elastic member 18 ... stapler unit 18a ... rotating shaft 19 ... anvil part (Bent portion) 19a staple point 23 stopper 23a roller 23b pinion gear 23c shaft 23d stopper gear 23e rack gear 24a 24b: Width-adjusting member 24c: Pinion gear 24d: Width-adjusting motor 24e: Width-adjusting home sensor 25: Projecting unit 25a: Projecting plate 25d, 25b: Holder 25c, 25e: Shaft 26, 27 ... Folding roller 28 ... Discharge guide 29 ... Discharge sensor 30 ... Discharge rollers 30a, 30b, 30c, 30d ... Roller 30e ... Shaft 30f ... Pulley 30g ... Rib 31 ... Discharge roller 32 ... Loading tray 33 ... Sensor 51 ... Transport motor 52 ... Transport motor pulley 53, 54 ... Timing belt 61 ... Stopper motor 62 ... Gear 63 ... Stopper home sensor 64 ... Folding motor 65 ... Pulley 66 ... Timing belt 67 ... Idler gear pulley 68,69 ... Folding gear 70 ... Timing belt 71 ... Link 72,73a, 76 ... Shaft 73 ... Gear 74 ... pulley 74a ... electromagnetic clutch 75 ... idler gear 81 ... flag 82 ... home sensor 83 ... entrance sensor 84 ... stack sensor 91 ... discharge motor 92 ... pulley 93 ... Timing belt 95 Stacker discharge motor 96, 98 Pulley 97 Timing belt 99 Support plate 100 Drive unit 101 Driving part (forming part) 102, 111 Guide member 102a Guide surface 103 Binding surface 104 Needle cartridge 105 ... binding needle 106 ... spring 107 ... feed roller 108 ... stapler motor 109 ... gear train 110 ... eccentric cam gear 111a ... notch hole 150 ... control device 900 ... image forming apparatus main body 901 ... registration roller 902 ... image forming unit 904 ... fixing device 905: discharge roller pair 905a: discharge roller 905b: discharge roller 906: platen glass 907: light source 908: lens system 909: paper feed unit 910, 911: cassette 912: pedestal 913: deck 914: photosensitive drum 915: developing unit 916 … Transfer charger 917… Separation charger 918… Cleaner 919… Primary charger 920… Transfer device

Claims (5)

[Claims] A first sheet stacking unit capable of stacking a plurality of sheets; a first sheet conveying unit configured to convey the sheet to the first sheet stacking unit; and a sheet stacked on the first sheet stacking unit. A sheet binding means for binding a plurality of aligned sheets at a substantially central portion in the transport direction of the first sheet transporting means; and Sheet bundle folding means for folding, a second sheet stacking unit for stacking the folded sheet bundle, and a second sheet conveying unit for conveying the folded sheet bundle to the second sheet stacking unit. When conveying a sheet bundle to the second sheet stacking unit, if the length in the width direction orthogonal to the conveying direction of the sheet bundle is shorter than a predetermined length, the sheet bundle is not bent. Transport, Serial sheet processing apparatus length in the width direction of the sheet bundle, characterized in that the conveying while bending the sheet bundle in the width direction is longer than a predetermined length. 2. The second sheet conveying means includes a first conveying roller and a second conveying roller having different outer diameters from each other, and a sheet bundle having a length in the width direction shorter than a predetermined length is a first conveying roller. The sheet bundle whose length in the width direction is longer than a predetermined length is nipped and conveyed by the first conveyance roller, and the vicinity of the width direction end of the sheet bundle is higher than the nipping position of the first conveyance roller. The sheet processing apparatus according to claim 1, wherein the sheet is conveyed by a second conveyance roller so as to be lowered. 3. The second sheet conveying means includes: a first conveying roller provided near the center in the width direction; and a second conveying roller having an outer diameter larger than the first conveying roller and provided near both ends in the width direction. A sheet bundle whose length in the width direction is shorter than the distance between the second conveyance rollers is nipped and conveyed by the first conveyance roller, and the length in the width direction is shorter than the distance between the second conveyance rollers. The long sheet bundle is conveyed by a second conveying roller while being pinched and conveyed by a first conveying roller such that the vicinity of both ends in the width direction of the sheet bundle is higher than a pinching position of the first conveying roller. 2. The sheet processing apparatus according to 1. 4. The apparatus according to claim 2, wherein a coefficient of friction of a member forming the second conveying roller is smaller than a coefficient of friction of a member forming the first conveying roller. A sheet processing apparatus according to claim 1. 5. An image forming apparatus comprising the sheet processing apparatus according to claim 1. Description: