JPH10120276A - Sheet post-treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To arrange many pieces of sheet in order with precision by constituting a discharge tray member by an energizing means which supports a sheet loading member side in such a manner that it can travel freely in the vertical direction and energizes a bottom plate part upward and a regulation means which regulates energization in the upward direction of the energizing means at a fixed position. SOLUTION: A sheet 41 introduced through an introduction port 42 of a sheet post-treatment device main body 40 is conveyed on a sheet loading member 45 through guide members 43, 44 and a conveying roller 46. The sheet 41 is loaded in a condition in which a tip fringe thereof is in contact with a reference fence 47 and is loaded in a condition in which a rear end part thereof rides over a discharge tray 59. This discharge tray 59 consists of a bottom plate part 100 in which the sheet loading member 45 side is supported in such a manner that it can travel freely in the vertical direction, a spring 104 which energizes the bottom plate part 100 upward, and a set clamp 106 which regulates the energization in the upward direction of the spring 104 at a fixed position. Consequently, a top face of the sheet 41 is set to a fixed position at all times.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus used in an image forming apparatus such as an electrophotographic copying machine, a printer, or a facsimile, and more particularly, to a stapling process for binding a plurality of sheets on which images are formed. The present invention relates to a sheet post-processing apparatus for discharging a sheet after post-processing.

[0002]

2. Description of the Related Art Conventionally, as this type of sheet post-processing apparatus, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 2-144370. The sheet post-processing apparatus according to Japanese Patent Application Laid-Open No. 2-144370 discloses a first post-processing apparatus for performing post-processing on a sheet.
And a second post-processing device, wherein the first post-processing device and the second post-processing device are disposed adjacent to each other, and the first post-processing device and the second post-processing device are disposed adjacent to each other. The first and second post-processing means are configured to be able to stack sheets over the post-processing means, and to perform post-processing by the first and second post-processing means. A transport means for transporting a sheet stacked over the processing means or a non-post-processed sheet transported from the upstream to the second post-processing means is provided.

[0003] The sheet post-processing apparatus according to Japanese Patent Laid-Open Publication No. 2-144370 has a first post-processing means and a second post-processing means adjacent to each other, based on the above configuration.
Since the sheet is stacked on the first and second post-processing means and post-processed by the first and second post-processing means, the apparatus can be downsized. . In addition, since there is provided a transport unit that transports the stacked sheets or the non-post-processed sheet transported from the upstream to the first and second post-processing units to the second post-processing unit, a vacuum transport unit is required. Instead, the image of the sheet and the alignment / binding condition can be checked at all times, and if a problem occurs, the countermeasure can be taken quickly. Furthermore, a tray for non-post-processed sheets is not required, and the apparatus can be downsized. Further, it is expected that operability can be improved by having a control means for controlling the position and operation of the transport means by operating / deactivating the first post-processing means and the second post-processing means. It is.

[0004]

However, the prior art described above has the following problems. That is, in the case of the sheet post-processing apparatus according to Japanese Patent Application Laid-Open No. 2-144370, as shown in FIG. Is applied to the first and second post-processing means 202 and 203. If the height of the surface 204 for receiving the discharged sheet 201 is not exactly constant when the sheets are aligned, the sheet 201 is aligned in an appropriate state. In an extreme case, the sheet 201 slips off the second post-processing means 203.

As a means for solving such a problem and for keeping the height of the surface receiving the discharged sheet constant when the sheets are aligned, a sensor is used to detect the height of the upper end surface of the sheets stacked on the discharge tray. It is conceivable to move the discharge tray up and down by a motor.

However, the height of the upper end surface of the sheets stacked on the discharge tray is detected using a sensor,
When the discharge tray is configured to be moved up and down by a motor, parts such as sensors and a motor are required, which complicates the configuration of the device and increases the cost and space. Occurs.

Therefore, the present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to make it possible to arrange a large number of sheets accurately with a simple structure and at low cost. It is another object of the present invention to provide a sheet post-processing apparatus.

[0008]

That is, a sheet post-processing apparatus according to a first aspect of the present invention includes a discharge tray member for holding a sheet discharged from an image forming apparatus in a stacked state. In the sheet post-processing apparatus, the discharge tray member is supported at least on the sheet mounting member side so as to be movable in the vertical direction, and a bottom plate portion on which a post-processed sheet is stacked, and biases the bottom plate portion upward. An urging means and a regulating means for pressing the upper surface of the sheets stacked on the bottom plate portion to regulate the urging of the urging means in an upward direction to a predetermined position are provided.

According to a second aspect of the present invention, in the sheet post-processing apparatus, the regulating means is a paddle made of an elastic member, and the discharge tray member on the side where the paddle is provided is provided with a sheet. Is configured to provide a member having a high friction coefficient at a portion where the edge of the contact is provided.

Further, the sheet post-processing apparatus according to the third aspect of the present invention conveys a plurality of sheets on which images are formed, and aligns the plurality of sheets on the basis of one end of the sheets. The sheet is stacked on the sheet stacking member, and the other end of the sheet is stacked on a discharge tray member provided adjacent to the sheet stacking member. After performing post-processing by the processing means,
In a sheet post-processing apparatus that discharges a post-processed sheet onto a discharge tray member, the discharge tray member supports the post-processed sheet so that at least a sheet mounting member side is vertically movable. A bottom plate portion to be stacked, an urging means for urging the bottom plate portion upward, and pressing the upper surface of the sheet stacked on the bottom plate portion to apply an urging force in the upward direction at a predetermined position. And a restricting means for restricting the pressure.

[0011]

According to the present invention, the discharge tray member is supported at least on the sheet mounting member side so as to be movable in the vertical direction, and a bottom plate portion on which a post-processed sheet is stacked, and biases the bottom plate portion upward. Since it is configured to include an urging unit and a regulating unit that presses the upper surface of the sheet stacked on the bottom plate unit to regulate the upward urging of the urging unit to a fixed position. The bottom plate portion on which the post-processed sheet is stacked is urged upward by the urging means, and the upper surface of the sheet stacked on the bottom plate portion is pressed by the regulating means at a predetermined position. Therefore, the sheet to be subjected to the next post-processing always has a fixed loading position, does not use a sensor or a motor, and has a simple configuration and a low cost to arrange a large number of sheets with high accuracy. Possible To become.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings.

FIG. 2 shows an image forming apparatus to which a sheet post-processing apparatus according to an embodiment of the present invention can be applied.

In FIG. 1, reference numeral 1 denotes an ADF (Auto Document Feeder) image of a document (not shown).
It indicates an image input unit to be read using or a series of image information is input from a host computer or the like,
The input image information is output from the image input unit 1 to the laser scanning unit 2. The laser scanning unit 2 places the photosensitive drum 3 uniformly charged in advance by the primary charger 4 in advance,
An electrostatic latent image is formed by irradiating a laser beam based on image information at one or two exposure positions according to an image forming mode. The electrostatic latent image formed on the photosensitive drum 3 is developed by a developing device 5 and / or a developing device 6 with toners of different colors as necessary. Further, the toner image developed on the photosensitive drum 3 is supplied from a paper storage unit 9 of a paper supply unit 10 and is transferred onto a recording paper S fed at a predetermined timing by a registration roll 11 onto a transfer roll S. 7 is transcribed. The recording sheet S to which the toner image has been transferred is conveyed to the fixing device 13 by the conveying belt 12, and the toner image is fixed on the recording sheet S by the fixing device 13 by heat and pressure. Recording paper S on which the toner image is fixed
Depending on the image forming mode, the sheet may be discharged through the discharge path 16 by the discharge roll 15 to the outside of the apparatus, or may be fed by the sheet reversing mechanism 14 into the input path 17 or the output path 18.
If necessary, the paper is discharged from the discharge roll 15 to the image forming portion of the photosensitive drum 3 via the double-sided / multiple-recording path 26 in a state where the transport direction and the front and back are reversed as necessary. The sheet is conveyed and double-sided or multiple recording is performed.

After the image forming process is completed, the surface of the photosensitive drum 3 is cleaned of residual toner and the like by the cleaning device 8 so as to be ready for the next image forming process.

FIG. 3 shows a sheet reversing mechanism of the image forming apparatus.

In FIG. 3, reference numeral 14 denotes a sheet reversing mechanism provided in a discharge section of the image forming apparatus. A paper reversing mechanism 14 is provided between the transport roll 13a and the discharge roll 15 of the fixing device 13 of the image forming apparatus. A discharge passage 16 is formed in a straight line obliquely upward, and below the discharge passage 16, a feed passage 17 extending obliquely downward from an upstream side of the discharge passage 16 in the conveyance direction of the recording sheet S. And a delivery passage 18 extending obliquely downward from the downstream side of the discharge passage 16 in the conveyance direction of the recording sheet S, are arranged so as to form a substantially triangular shape. A switching member 27 for switching the recording sheet S discharged from the fixing unit 13 between the discharge passage 16 and the feed passage 17 is provided at the entrance of the discharge passage 16 and the feed passage 17.
Are arranged so as to be tiltable.

The feeding path 1 of the sheet reversing device 14
A tri-roll 19, which constitutes a part of the sheet reversing device 14, is disposed between the sheet 7 and the delivery path 18. The tri-roll 19 is such that the nip between the first driven roll 19A and the driving roll 19B is located in the feed passage 17 and the nip between the driving roll 19B and the driven roll 19C is located in the delivery passage 18. The driven roll 19A, the driving roll 19B, and the driven roll 19C are arranged in a state where they are pressed against each other.

Further, the inlet passage 17 and the outlet passage 18
As shown in FIG. 3, a reversing passage 25 is connected to the lower end of the merging portion located at the lower end of the reversing passage 25 in an inclined state. 25A and a double-sided / multiple-recording path 26 are formed so as to be branched. A switching member 20 for switching the transport direction of the recording paper S is disposed at a branch between the drawing-in portion 25A and the duplex / multi-recording passage 26, and a lower end of the switching member 20 has a mylar sheet or the like. A shield plate 31 made of a synthetic resin film is provided to project downward. The switching member 20 is arranged so that the shield plate 31 comes to a position shown in the drawing in a normal state. A forward / reverse rotation roll 21 and a pinch roll 22 for transporting the recording paper S are disposed at the upper end of the draw-in section 25A so as to be able to press against each other. This pinch roll 22
The pressure contact state with the forward / reverse rotation roll 21 can be released by the solenoid 24 via the link 23.

In FIG. 3, reference numeral 23A indicates a fulcrum of the link 23, reference numeral 24A indicates an operating rod of the solenoid 24, and reference numeral 29 indicates a detection unit of the recording paper detection sensor 28.

In the sheet reversing mechanism 14 configured as described above, a sheet reversing operation is performed as follows.

In the single-sided copy normal discharge mode of the image forming apparatus, the drive motor for driving the drive roll 19B of the tri-roll 19 of the sheet reversing mechanism 14 is stopped, and as shown in FIG. In a state where the switching member 27 disposed in the section is lowered, the fixing device 1
The recording paper S, which has been subjected to the fixing process in Step 3, passes above the switching member 27 via the discharge path 16 and is directly discharged to the discharge roll 15.
From the device.

In the one-sided copy reversal discharge mode of the image forming apparatus, the triroll 1 of the paper reversing mechanism 14 is used.
9 is started, and the driven roll 19A of the tri-roll 19 and the driving roll 1B are driven.
9B and the driven roll 19C are rotationally driven. further,
As shown in FIG. 3, the switching member 27 disposed in the discharge passage 16 is lifted upward by a solenoid (not shown), and is switched from the discharge passage 16 to the inlet passage 17. Then, the recording paper S fixed by the fixing device 13 is processed.
The transport direction is switched by the switching member 27 and is transported to the feed passage 17, and is guided to a nip portion composed of a driven roll 19 </ b> A and a drive roll 19 </ b> B located in the feed passage 17, and the drive roll 19 </ b> B By the driving force of
It is guided to the forward / reverse roll 22 in the forward rotation state via the reverse passage 25. As a result, the recording paper S is once guided into the reversing passage 25 by the forward / reverse rotation roll 22 in the normal rotation state, but the upper end of the recording paper S is higher than the lower end of the shield plate 31 of the switching member 20. Located in.

The upper end of the recording sheet S once guided into the reversing passage 25 by the forward / reverse roll 22 is located above the lower end of the shield plate 31 of the switching member 20, so that the recording paper S reverses. It is again conveyed to the reversing passage 25 by the reversing roll 21, and is guided to a nip portion composed of a driving roll 19 </ b> B and a driven roll 19 </ b> C arranged in the delivery passage 18 via the reversing passage 25, and is conveyed. It is conveyed to the discharge roll 15 by force.

Further, in the two-sided copying mode in the image forming apparatus, a driving motor for driving the driving roll 19B of the tri-roll 19 of the sheet reversing mechanism 14 is activated, and the driven roll 19A and the driving roll 19B of the tri-roll 19 are driven. The switching member 27 disposed in the discharge passage 16 is lifted upward by a solenoid (not shown) as shown in FIG. 3, and is switched from the discharge passage 16 to the inlet passage 17. The operation up to being guided to the forward / reverse roll 21 in the forward rotation state is the same as that in the one-sided copy reversal discharge mode. When the reversal timing of the recording paper S is delayed from the one-sided copy reversal discharge mode, the upper end of the recording paper S is at the lower end of the switching member 20 disposed at the branch between the reversing path 25 and the duplex / multiplex recording path 26. The switching member 20 is switched to the double-sided / multiplex recording path 26 by its own weight.
Therefore, the recording sheet S conveyed again by the forward / reverse roll 22 in the reverse rotation state is conveyed via the switching member 20 to the double-sided / multiple recording path 26 with the surface on which the toner image is formed facing up. . As shown in FIG. 2, the recording sheet S is again passed through the double-sided / multiple-recording passage 26 formed so as to be bent and folded, with the toner image formed on the image forming unit 26 facing down. And a toner image is formed on the back surface of the recording paper S. The subsequent operation is the same as in the single-sided copy normal discharge mode. After the recording paper S having the toner images formed on both sides passes through the fixing device 13, the recording paper S is discharged outside the apparatus by the discharge roll 15 through the discharge passage 16. Is discharged.

Incidentally, if necessary, in the case of the single-sided multiple recording mode, the recording paper S on which the toner image is formed on one side is used.
However, the surface on which the toner image is formed is transferred to the photosensitive drum 3 via the reversing passage 25 and the duplex / multiplex recording passage 26 without being conveyed to the retracting portion 25A of the reversing passage 25 by switching of the switching member 20. Is conveyed again to the image forming section so that the toner image on the surface of the recording paper S is multiplex-transferred and discharged in the same manner as in the single-sided copy normal discharge mode.

FIG. 4 shows a sheet post-processing apparatus according to an embodiment of the present invention which is used in combination with the above-mentioned image forming apparatus.

In the figure, reference numeral 40 denotes a main body of the sheet post-processing apparatus.
0 is arranged so as to face the paper discharge unit of the image forming apparatus. On the upper side of one side of the sheet post-processing apparatus main body 40,
A sheet introduction port 42 into which a sheet 41 of recording paper S or the like discharged from a paper ejection unit of the image forming apparatus is introduced is opened, and a guide member for guiding the sheet 41 is provided inside the sheet introduction port 42. A transport roll 46 for sequentially transporting the sheet 41 transported via 43 and 44 onto a sheet mounting member 45 is disposed. As shown in FIG. 4, the sheet placing member 45 is attached to the sheet post-processing apparatus main body 40 in an inclined state. As shown in FIG. In addition, a reference fence 47 for aligning one end edge of the sheet 41 is rotatably mounted. Then, the transport roll 46
The sheet 41 conveyed is placed on a sheet placing member 45 attached in an inclined state,
The Y direction is moved by the tamper 95 as shown in FIG. 5, and the X direction is moved by its own weight and the paddle 96 as shown in FIG. 4 according to the inclination of the sheet placing member 45, so that the edge of the sheet 41 hits the reference fence 47. Stop in contact. The tamper 95 is, as shown in FIG.
The sheet placing member 45 can be moved in the Y direction by a driving unit (not shown) through the 5a and the long hole 95b. As a result, the sheet 41 sequentially conveyed by the conveyance roll 46 has one end edge thereof at the reference fence 47.
Are sequentially stacked on the sheet placing member 45 in a state where they are aligned. The tip 47a of the reference fence 47
Is folded forward to reliably prevent the sheets 41 stacked on the sheet placing member 45 from falling off.

The upper part of the sheet placing member 45 is shown in FIG.
As shown in FIG. 7, a guide member 97 is provided for guiding the weight of the sheet 41 itself and the edge of the sheet 41 fed by the paddle 96 into the opening 71a of the stapler 71. As shown in FIG. 7, the guide member 97 is a horizontal plate portion 9 that is disposed substantially horizontally and guides the sheet 41 conveyed by the guide members 43 and 44 and the conveyance roll 46.
7a, a hanging plate portion 97c which is hung downward at approximately 90 degrees through a curved portion 97b at an end of the horizontal plate portion, and a tip 4 of the reference fence 47 is attached to a lower end portion of the hanging plate portion 97c.
And an inclined plate 97d inclined toward the 7a side. The inclined plate portion 97d of the guide member 97 is transported onto the sheet placing member 45 by the transport rolls 46, and the weight of the sheet 41 itself and the sheet 41 sent to the distal end portion 47a side of the reference fence 47 by the paddle 96. As shown in FIG. 6, the extending direction of the inclined plate portion 97 d is disposed so as to be positioned within the opening 71 a of the stapler 71 so that the end edge can be reliably guided into the opening 71 a of the stapler 71. Have been. The above stapler 71
Is composed of a die portion 91 to which a die for bending the tip of the staple is attached, and a staple portion 92 for accommodating the staple and tilting so as to come into contact with the die portion. The opening 71a in which the edge of the sheet 41 to be sequentially laminated is disposed
Is provided. In this embodiment, as shown in FIG. 8, when the stapler 71 aligns the sheet 41 with the opening 71 a in a stacked state, the edge of the sheet 41 is surely located in the opening 71 a. , The die portion 91 and the staple portion 92 are slightly rotated in the counterclockwise direction so that the opening 71 a faces the edge of the sheet 41. If the opening 71a of the stapler 71 is set large, the stapler 71 does not need to be configured to tilt.

The inclined plate portion 97 of the guide member 97
As shown in FIG. 7, the notch 9 is located at a position where it interferes with the stapler 71 that has moved to an oblique position at the corner of the sheet, as shown in FIG.
7e is provided to prevent the stapler 71 from interfering with the inclined plate portion 97d of the guide member 97 even when the stapler 71 moves to an oblique position at a corner of the sheet 41.

Further, the reference fence 47 can be retracted by pivoting downward. The reference fence 47 includes a rotating shaft 48 as shown in FIG.
The rotary shaft 48 is mounted on a support plate 49 erected on the sheet placing member 45 by bearings 5.
It is rotatably supported via a zero. An L-shaped plate 52 having a shaft portion 51 for rotating the reference fence 47 is screwed to one end of the rotary shaft 48.
Further, as shown in FIG. 9, the shaft portion 51 of the L-shaped plate 52 is loosely inserted into a U-shaped groove portion 54 provided on a rotating member 53, and the rotating member 53 is provided with a drive motor. A gear portion 57 that meshes with a gear 56 that is driven to rotate by 55 is provided. And the reference fence 47 is
By rotating the drive motor 55, the rotating member 5 is rotated.
3 is rotated, and the U-shaped groove portion 54 of the rotating member 53 is rotated.
It is rotatable downward, for example, at an angle of 100 degrees via a shaft portion 51 loosely inserted into the shaft portion 51.

The sheet placing member 45 has a structure shown in FIG.
Is placed on the sheet placing member 45,
Two injection rolls 58 for discharging a set of a plurality of sheets 41 subjected to stapling processing are arranged along the width direction so as to be rotatable by a driving unit (not shown).

Further, above the injection roll 58, the sheet 41 laminated with the injection roll 58 is held in a sandwiched state, and after the stapling process is completed, the sheet 41 is placed on the sheet post-processing apparatus main body 40. A pinch roll 60 that conveys the sheet to a discharge tray member 59 provided outside the printer is provided. As shown in FIG. 4, the pinch roll 60 is rotatably attached to a distal end portion of a mounting plate 61 made of a leaf spring, and the mounting plate 61 is rotatably mounted around a rotating shaft 62. Have been. As shown in FIG. 10, an arm member 63 for rotating the mounting plate 61 is attached to one end of the rotating shaft 62.
An eccentric roller 66, which is rotationally driven by the drive motor 64 and is mounted at an eccentric position with respect to the rotation shaft 65 of the drive motor 64, comes into contact.
Further, a slit plate 68 provided with a slit 67 over a predetermined angle is attached to the rotation shaft 65 of the drive motor 64.
Is detected by two sensors 69 and 70 arranged at positions 180 degrees opposite to each other. When the mounting plate 61 rotates the drive motor 64, the eccentric roller 66, which is rotationally driven by the drive motor 64, pushes down the arm member 63 and rotates the rotary shaft 62 to which the arm member 63 is attached. As a result, the pinch roll 60 and the injection roll 58 together with the sheet 4
1 is pinched. At this time, the movement amount and movement timing of the pinch roll 60 are determined by the slit plate 6.
8 and sensors 69 and 70.

A stapler 71 for binding a plurality of sheets 41 placed on a sheet placing member 45 and having its edges aligned with the reference fence 47 is mounted inside the sheet post-processing apparatus main body 40. Stapler section 72
Are arranged to be movable in parallel along the edge of the sheet 41 by the moving mechanism 73.

The moving mechanism 73 of the stapler 72 is
As shown in FIG. 11, a guide rail 74 for guiding the stapler section 72 in parallel along the edge of the sheet 41 is provided.
1 and a linear portion 74a corresponding to the length in the longitudinal direction.
And inclined portions 74b and 74c provided at both ends of the straight portion so as to be inclined at 45 degrees. The guide rail 74 includes two guide rollers 75 and 76 provided at the upper end of the stapler 72 along the moving direction.
Are adapted to travel in a fitted state. Therefore, the path along which the stapler 72 moves is defined by the shape of the guide rail 74. As shown in FIGS. 4 and 11, the guide rail 74 is screwed in a state fitted in a recess 78 provided in the guide plate 77. As shown in FIG. 11, the upper end of the stapler section 72 has two
On the other hand, one guide roller 79, 79, 80 rotatably mounted on the opposite side runs. As a result, the position of the stapler section 72 in the direction perpendicular to the moving direction is regulated by the two guide rollers 75 and 76 running in the guide rail 74, and the position in the vertical direction runs on the guide plate 77. The stapler unit 72 is configured to move while being regulated by the three guide rollers 79, 79, and 80. The plane on which the stapler unit 72 moves corresponds to the sheet 4 placed on the sheet placing member 45.
1 and the same plane.

Further, as shown in FIG. 4, the guide plate 77 on which the guide rails 74 are mounted is mounted on the sheet post-processing apparatus main body 40 by a mounting board 81 fixed and inclined as shown in FIG. In order to maintain a constant interval through the bush 82,
3 has been stopped. Further, five driven pulleys 85 that rotatably support a drive belt 84 for moving the stapler section 72 are rotatively mounted on the mounting substrate 81. As shown in FIG. 11, the drive belt 84 is wound around five driven pulleys 85 and a part 84 a of the drive belt 84 is fixedly connected to the stapler 72. Of the five driven pulleys 85, a central driven pulley 85a is movably supported in a direction orthogonal to the moving direction of the stapler 72,
The drive belt 84 is urged by a spring (not shown) so as to always apply a constant tension.

Further, among the five driven pulleys 85,
As shown in FIG. 13, the driven pulley 85b at one end has
Driving pulley 87 rotated and driven by driving motor 86
A belt 88 for transmitting the driving force is stretched around. The drive belt 84 can reciprocate by an arbitrary amount in an arbitrary direction by rotating a drive motor 86, and moves the stapler unit 72 connected to the drive belt 64. is there. The driven pulley 85 and the driving belt 84 are disposed between the guide plate 77 and the mounting board 81.

As shown in FIGS. 4 and 11, the stapler 72 driven by the drive belt 84 has a position detecting member 89 attached to the stapler 72.
Is detected by a reference position sensor 90 provided on the sheet post-processing apparatus main body 40 side, and a reference position is detected.
The moving position is controlled by controlling the amount of rotation of. The reference position sensor 90
As shown in FIG. 14, in addition to the position corresponding to the first staple position A of the sheet 41 of a predetermined size (for example, A5 size), the positions B and C corresponding to the oblique positions of both corners of the sheet 41 are Are also provided.

Further, as shown in FIG. 4, the stapler 71 is rotated around a fulcrum so as to abut against the die 91 fixed to the stapler 72. Staples that move to protrude the staple needles housed therein, penetrate the plurality of stacked sheets 41, and turn the staples back by the die of the die part 91 so as to face each other to perform a stapling process. And a part 92. This stapler 7
The one staple portion 92 is rotatable around a fulcrum through a plurality of gears 94 driven by a drive motor 93 so as to contact the die portion 91. Further, the stapler 71 moves so that the die 91 and the staple 92 face each other via the edge of the sheet 41 after the reference fence 47 is retracted. At this time, the stapler 71 is attached to the guide rail 74 and the guide plate 77 so that the die portion 91 of the stapler 71 and the surface of the sheet 41 are parallel to each other, as shown in FIG.

By the way, in the sheet post-processing apparatus according to this embodiment, the discharge tray member is supported at least on the sheet mounting member side so as to be vertically movable, and has a bottom plate portion on which the post-processed sheets are stacked. Urging means for urging the bottom plate upward, and regulating means for pressing the upper surface of the sheets stacked on the bottom plate to restrict the urging of the urging means to a predetermined position. Are provided.

That is, as shown in FIGS. 1, 15 and 16, the discharge tray member 59 is attached obliquely upward to the outside of the sheet post-processing apparatus main body 40 on the sheet discharge side. The other end of the sheet 41 to be post-processed, which is stacked on the mounting member 45, is stacked so as to straddle the sheet mounting member 45. The discharge tray member 59 includes a bottom plate portion 100 on which the post-processed sheet 41 is stacked and the bottom plate portion 100.
Side plate portions 101 arranged on both ends of the bottom plate portion 10 and the bottom plate portion 10
And a contact portion 102 that is disposed at an inclined position at the base end portion of the sheet 41 and in which the front end portion of the post-processed sheet 41 contacts. The bottom plate 100 has a fulcrum 103 at its tip.
Is mounted on both side plate portions 102 so as to be rotatable around the center, and the base end side thereof is movable in the vertical direction. The bottom plate 100 is urged upward by a spring 104, and the lower end of the spring 104 is supported by a mounting plate 105 bridged between both side plates 101. Further, the surface of the abutting portion 102 is in contact with the base end of the post-processed sheet 41 stacked on the bottom plate portion 100, and has a frictional force with the base end of the sheet 41. Acts on the spring 1
A member having a high coefficient of friction, such as rubber, is attached so as to restrict the upward movement of the sheet 41 by the urging force of 04.

As shown in FIG. 1, the upper surface of the post-processed sheet 41 stacked on the discharge tray member 59 is pressed against the end of the sheet post-processing apparatus main body 40 on the sheet discharge side. A set clamp 106 as a restricting means for restricting the upward biasing of the spring 104 to a fixed position is disposed coaxially with the injector roll 58. As shown in FIG. 17, the set clamp 106 includes a paddle 107 made of an elastic member such as rubber or plastic, and a support piece made of a rigid member such as hard plastic laminated below the base end of the paddle 107. 108.

In the above-described configuration, the sheet post-processing apparatus according to this embodiment can easily arrange a large number of sheets at a low cost with a simple configuration as follows.

That is, in the image forming apparatus in which the above-mentioned sheet post-processing apparatus is combined, as shown in FIG.
When a document is read using a document feeder or a series of image information is input from a host computer or the like, a toner image is formed on the photosensitive drum 3 based on the image information output from the image input unit 1. The toner image formed on the photosensitive drum 3 is fed from the paper storage unit 9 of the paper feed unit 10 and is conveyed by the registration roll 11 at a predetermined timing.
It is transferred by a transfer roll 7 on the upper side. The fixing device 13 fixes the toner image on the recording paper S to which the toner image has been transferred by heat and pressure. Then, the sheet 41 made of the recording paper S or the like onto which the toner image has been transferred is ejected from the image forming apparatus by the paper reversing mechanism 14 shown in FIG. The sheet is sent to a sheet post-processing apparatus disposed so as to be continuous with the sheet discharge section of the forming apparatus.

In the above-described sheet post-processing apparatus, as shown in FIG. 4, the sheet 41 discharged from the image forming apparatus is introduced through an inlet 42 of the sheet post-processing apparatus main body 40. The sheet 41 introduced into the main body of the sheet post-processing device 40 is conveyed onto the sheet placing member 45 via the guide members 43 and 44 and the conveying roll 46, and is inclined by its own weight and the paddle 96. The sheet is slid on the sheet placing member 45 arranged in this state, and is placed on the sheet placing member 45 in a state where the edge thereof is in contact with the reference fence 47. At that time, the last sheet 41 on which an image has been formed by the image forming apparatus is conveyed via the guide members 43 and 44 and the conveying rolls 46, and this sheet 41 is
As shown in FIG. 18A, when the sheet is detected by a sheet discharge sensor (not shown) arranged on the front side of the transport roll 46, the transport roll 46 is decelerated as shown in FIG. 18C. Thereafter, the sheets 41 continuously introduced into the sheet post-processing apparatus main body 40 are sequentially stacked and mounted on the sheet mounting member 45 with the edges thereof abutting on the reference fence 47. You. At this time, the drive motor (not shown) for driving the tamper 96 is reciprocated twice for a short time as shown in FIG.
6 is reciprocated to align the edges of the sheet 41.

At this time, the sheets 41 placed in a state of being sequentially stacked on the sheet placing member 45 are placed in a state where the leading edge thereof is in contact with the reference fence 47 as shown in FIG. While being loaded on the mounting member 45,
The rear end is stacked while being straddled on a discharge tray 59 provided outside the sheet post-processing apparatus main body 40.
If the post-processed sheet 41 is already stacked on the discharge tray 59, the sheet 41 to be newly post-processed is subjected to the post-processing performed on the discharge tray 59. The sheets are stacked while being straddled on the sheet 41 that has been set. When the post-processed sheet 41 is not stacked on the discharge tray 59, the sheet 41 to be newly post-processed straddles the bottom plate 100 of the discharge tray 59. It is loaded in a state.

Next, as shown in FIG. 18 (e), by driving the drive motor 64 shown in FIGS. 4 and 10, the mounting plate 61 on which the pinch roll 60 is mounted is rotated.
Is rotated, and the pinch roll 60 is pressed into contact with the injection roll 58 via the plurality of stacked sheets 41 so that a predetermined number of sheets 41 placed in a stacked state on the sheet placing member 45. Is pinched by the pinch roll 60 and the injection roll 58.

After that, as shown in FIGS. 5 and 9, the drive motor 55 is rotated to rotate the reference fence 47 downward, and the reference fence 47 is retracted from the movement path of the stapler 71. Let it. In this state,
As shown in FIG. 4, FIG. 11 and FIG.
The stapler 72 is moved to a predetermined position by driving a drive motor 86 that moves the stylus 2 to move the drive belt 84. Then, the stapler 71 moved to a predetermined position along the edge of the sheet 41 causes the stapler 71 shown in FIG.
As shown in (f), the motor for driving the stapler 71 is activated to perform the stapling process on the edge of the sheet 41.

In this embodiment, as shown in FIG. 1, the discharge tray member 59 is supported on the sheet mounting member 45 side so as to be movable in the vertical direction. A bottom plate portion 100 to be loaded, a spring 104 for urging the bottom plate portion 100 upward, and an upper surface of the sheet 41 loaded on the bottom plate portion 100 are pressed to uniformly bias the spring 104 upward. And a set clamp 106 for regulating the position of the set clamp 106.

Therefore, as shown in FIG. 19, the set of a plurality of sheets 41 stapled by the stapler 71 is rotated at a predetermined timing as shown in FIG. The sheet is discharged onto the discharge tray member 59 in a state where the sheet is nipped between the sheet and the pinch roll 60.
Then, the set clamp 106 makes one rotation on the injection roll 58 several tens of milliseconds before the post-processed sheet 41 is discharged onto the discharge tray member 59 to prevent the discharging operation of the sheet 41 set. Without
As shown in FIG. 19, the upper surface of the set of sheets 41 discharged onto the discharge tray
9 is pushed down to a certain height and stopped at a predetermined position. At this time, the set of the post-processed sheets 41 discharged onto the discharge tray member 59 is set by a spring 104 for urging the bottom plate 100 of the discharge tray member 59 upward as shown in FIGS. Although it is pushed upward by the resilience Fs, the upper end surface of the seat 41 set is
The position is regulated to a certain height by the pressing force Fset of the set clamp 106, and the base end of the sheet 41 set is in contact with the contact portion 102 of the discharge tray member 59, which has a high coefficient of friction. Therefore, the sheet 4
Friction force acting on one set of base end faces (= μFp × sin
θ), the pressing force Fset of the set clamp 106 is
Does not act, the set clamp 106
To hold the position depressed. Thereafter, the set clamp 106 is rotated in the reverse direction as required, and retracted to a position where the post-processing of the next sheet 41 is not hindered. The spring force Fs of the spring 104 and the like are set so as to satisfy the relationship shown in FIG. 21 in order to perform the above operation smoothly.

As described above, in the sheet post-processing apparatus according to the embodiment, as shown in FIG.
Reference numeral 9 denotes a bottom plate portion 100 on which the sheet mounting member 45 side is movably supported in the up and down direction and on which the post-processed sheet 41 is stacked, a spring 104 for urging the bottom plate portion 100 upward, and the bottom plate Sheet 4 loaded on unit 100
And a set clamp 106 for pressing the upper surface of the spring 1 to restrict the upward biasing of the spring 104 to a predetermined position, so that the bottom plate on which the post-processed sheet 41 is stacked is provided. As shown in FIG. 19, the portion 100 is urged upward by a spring 104, and the upper surface of the sheet 41 stacked on the bottom plate portion 100 is pressed by a set clamp 106 to be restricted to a certain position. Therefore, the upper surface of the sheet 41 to be subjected to the next post-processing is always at a fixed position, and a large number of sheets can be arranged with a simple configuration and at low cost without using a sensor or a motor. Becomes

Embodiment 2 FIG. 22 shows Embodiment 2 of the present invention. The same portions as those in Embodiment 1 are denoted by the same reference numerals and described. The bottom plate portion of the discharge tray member is not rotatably mounted with one end as a fulcrum, but is mounted so as to be vertically movable in parallel.

That is, as shown in FIG. 22, the bottom plate portion 100 of the discharge tray member 59 includes a support portion 110 disposed below and in parallel with the bottom plate portion 100, and the bottom plate portion 110 is provided with a link. 111 via support portion 110
Is mounted so as to be able to move in parallel along the vertical direction. Further, the bottom plate portion 100 is urged upward by the urging force of a spring 112 having both ends fixed between the connecting portions of the two links 111.

In this embodiment, since the bottom plate 100 is attached so as to be able to move in parallel along the vertical direction,
The position of the upper surface of the sheet 41 stacked on the bottom plate portion 100 can be maintained at a constant position with higher accuracy, and the alignment of the sheet 41 can be performed with higher accuracy.

Other configurations and operations are the same as those of the first embodiment.
Therefore, the description is omitted.

Third Embodiment FIG. 23 shows a third embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals and described. As a restricting means for restricting the upward movement of the bottom plate, a ratchet mechanism for restricting the upward movement of the bottom plate other than the paddle member is used.

That is, in the third embodiment, FIG.
As shown in FIG. 7, the post-processing apparatus main body 40 serves as a restricting means for restricting the upward movement of the bottom plate 110 of the discharge tray 59.
A ratchet mechanism 120 provided between the outside of the bottom plate 100 and the bottom plate 100 is used, and when the upper surface of a sheet stacked on the bottom plate 100 is pressed by a paddle member, the bottom plate 100 is pushed down. The ratchet mechanism 120 operates to restrict the bottom plate 100 from moving upward.

In the case of such a configuration, the bottom plate 10
Since the ratchet mechanism 120 that presses the upper surface of the sheet 41 stacked on the upper side and regulates the urging means 104 in the upward direction to a predetermined position is used, the position of the upper surface of the sheet 41 is surely ensured. And the alignment of the sheet 41 can be accurately performed by a simple mechanism. It should be noted that the ratchet mechanism 120 completes a series of post-processing, and the sheet 41 stacked on the discharge tray 59.
After the is removed, the action of the ratchet is released by releasing means (not shown), and the bottom plate 100 is pushed upward to a predetermined stop position by the urging force of the spring 104.

Other configurations and operations are the same as those of the first embodiment.
Therefore, the description is omitted.

[0060]

According to the present invention, a sheet post-processing apparatus having the above-described structure and operation can be provided which has a simple structure and can arrange a large number of sheets accurately with low cost.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a first embodiment of a sheet post-processing apparatus according to the present invention.

FIG. 2 is a configuration diagram showing an embodiment of an image forming apparatus to which a post-processing apparatus according to the present invention can be applied.

FIG. 3 is a configuration diagram illustrating a sheet reversing mechanism of the image forming apparatus.

FIG. 4 is a configuration diagram showing an embodiment of a post-processing device according to the present invention.

FIG. 5 is a configuration diagram showing a sheet placing member and a reference fence.

FIG. 6 is a configuration diagram showing a main part of an embodiment of an image forming apparatus to which the post-processing apparatus according to the present invention can be applied.

FIGS. 7A, 7B, and 7C are a plan view, a front view, and a side view showing a guide member.

FIG. 8 is a configuration diagram showing a main part of an embodiment of an image forming apparatus to which the post-processing apparatus according to the present invention can be applied.

FIG. 9 is a configuration diagram illustrating a driving unit of a reference fence.

FIG. 10 is a configuration diagram showing a driving unit of a pinch roll.

FIG. 11 is a plan view showing a stapler moving mechanism.

12 (a) and 12 (b) are cross-sectional views each showing a main part of FIG. 11;

FIG. 13 is a side view showing a driving unit of the driving belt.

FIG. 14 is an explanatory diagram showing a moving path of the stapler.

FIGS. 15A, 15B, and 15C are a plan view, a front view, and a side view, respectively, illustrating a discharge tray member of the sheet post-processing apparatus according to the first embodiment.

FIGS. 16A, 16B, and 16C are a plan view, a front view, and a side view, respectively, showing a discharge tray member of the sheet post-processing apparatus according to the first embodiment.

FIG. 17 is a configuration diagram showing a set clamp.

FIG. 18 is a timing chart showing an operation of the embodiment of the post-processing apparatus according to the present invention.

FIG. 19 is a configuration diagram illustrating an operation of the sheet post-processing apparatus according to the first embodiment.

FIG. 20 is an explanatory diagram illustrating the operation of the sheet post-processing apparatus according to the first embodiment.

FIG. 21 is an explanatory diagram illustrating the operation of the sheet post-processing apparatus according to the first embodiment.

FIG. 22 is a configuration diagram illustrating a sheet post-processing apparatus according to the second embodiment.

FIG. 23 is a configuration diagram showing a sheet post-processing apparatus according to the third embodiment.

FIG. 24 is a configuration diagram showing a conventional sheet post-processing apparatus.

[Description of References] 41 sheets, 45 sheet placing members, 59 discharge tray members, 100 bottom plate portion, 104 springs (biasing means), 106 set clamps (restriction means).

Claims (3)

[Claims] 1. A sheet post-processing apparatus provided with a discharge tray member for holding a sheet discharged from an image forming apparatus in a stacked state, wherein the discharge tray member is movable at least on a sheet mounting member side in a vertical direction. A bottom plate portion on which the supported and post-processed sheets are stacked, an urging means for urging the bottom plate portion upward, and the urging means for pressing an upper surface of the sheets stacked on the bottom plate portion And a restricting means for restricting the upward bias to a predetermined position. 2. The method according to claim 1, wherein the restricting means is a paddle made of an elastic member, and a member having a high friction coefficient is provided at a portion where the edge of the sheet comes into contact with the discharge tray member on the side where the paddle is provided. The sheet post-processing apparatus according to claim 1, wherein: 3. A plurality of sheets on which an image is formed are conveyed, stacked on a sheet placing member with one end of the sheets aligned as a reference, and the other end of the sheets are stacked on a sheet. The stacked sheets are stacked on a discharge tray member provided adjacent to the mounting member, and the aligned sheets are subjected to post-processing by post-processing means. In the sheet post-processing device for discharging onto a discharge tray member, the discharge tray member is supported at least on a sheet mounting member side so as to be movable in a vertical direction, and a bottom plate portion for stacking a post-processed sheet; Biasing means for biasing the portion upward, and regulating means for pressing the upper surface of the sheet stacked on the bottom plate portion to regulate the upward biasing of the sheet to a fixed position. The feature is that That the sheet post-processing apparatus.