JP7147398B2 - Sheet processing device and image forming device - Google Patents

Description

The present invention relates to a sheet processing apparatus that binds a bundle of sheets.

2. Description of the Related Art An image forming apparatus such as a printer includes a sheet processing apparatus that conveys a plurality of sheets after image formation one by one, stacks and accommodates them on a tray, aligns the sheet bundle, and binds the aligned sheet bundle. I have something installed.

There are two methods for binding sheet bundles: the staple binding method, in which a staple made of metal or the like is used to bind the sheet bundle, and the staple binding method, in which a pair of crimping teeth or other binding members are used to bind the sheet bundle with strong force. There is a stapleless binding system that allows Further, as a method of binding the corner of a sheet, there are parallel binding in which the binding part is parallel along the side edge of the sheet and oblique binding in which the binding part is slanted.

In Japanese Patent Application Laid-Open No. 2002-100000, two binding units, one that binds the corners of a sheet bundle by a staple-attached diagonal binding method and the other that binds the corners of a sheet bundle by a staple-free diagonal binding method, are arranged side by side, and the aligned sheet bundle is a binding unit that should be used. A configuration is disclosed in which oblique binding with or without a staple can be selectively performed by moving the binding member to the position of (FIG. 12).

JP 2015-20815 A

In Patent Document 1, two binding units are fixedly arranged exclusively for diagonal binding. However, for example, if one of the binding units is moved to enable parallel binding of different parts of a sheet bundle, both diagonal binding and parallel binding are possible. can also be selected, further enhancing user convenience.

However, when one of the binding units is configured to be movable, there arises a problem that the size of the device tends to increase.

FIG. 16A illustrates a configuration example including two binding units 910 and 920 for binding a sheet bundle Sb in which a plurality of sheets S are conveyed one by one onto a tray (not shown) and stacked and accommodated. is a schematic plan view of the.

The binding unit 910 shown in the figure is movable in the sheet width direction along the side edges 900 of the sheets, and is positioned anywhere from the corner 901 on the front side of the sheet bundle Sb to the corner 902 on the back side of the apparatus. A binding member 911 is used to perform parallel binding with a staple at that portion. The binding unit 920 is arranged in an inclined posture with respect to the sheet conveying direction, and applies stapleless oblique binding to the corner portion 902 of the sheet bundle Sb with the crimping teeth 921 .

In this configuration example, there is no problem in using the binding unit 920 to perform stapleless oblique binding on the corner portion 902 of the sheet bundle Sb. However, when the binding unit 910 is used to perform parallel binding with a staple at the corner 902 of the sheet bundle Sb, the binding unit 920 is moved away from the corner 902 of the sheet bundle Sb so that both binding units do not interfere with each other. It becomes necessary to evacuate to

As a method of retracting the binding unit 920, for example, similarly to the method of moving the binding unit 910, the binding unit 920 in the inclined posture is moved from the binding position shown in FIG. 16A to the retracted position shown in FIG. If a method of moving in parallel in the direction is adopted, the end portion 922 on the device rear side of the housing of the binding unit 920 after being moved to the retracted position protrudes considerably toward the device rear side with respect to the sheet bundle Sb. As the movement width of the binding unit 920 from the binding position to the retracted position increases, the space for allowing the movement (the difference between the distance Lα shown in FIG. 16A and the distance Lβ shown in FIG. 16B) increases. (equivalent) must be large, and the size of the apparatus will be increased accordingly.

The problem of this device size increase is that, for example, even if the binding unit 910 is of the stapleless binding system and the binding unit 920 is of the staple binding system, in order to prevent interference between the two binding units, the binding unit The same can occur with configurations that retract 920 from the binding position.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet processing apparatus and an image forming apparatus capable of preventing interference between two binding units and suppressing an increase in the size of the apparatus. and

In order to achieve the above object, a sheet processing apparatus according to the present invention is a sheet processing apparatus that stacks sheets conveyed onto a tray one by one and binds the stacked sheet bundle. a first binding unit that obliquely binds one corner of a sheet bundle in an inclined posture inclined at a predetermined angle with respect to a direction; In a case where a second binding unit capable of selectively binding a different portion including a corner and a job of binding the corner portion of the sheet bundle by moving the second binding unit, the second binding unit can bind the corner portion of the sheet bundle. before reaching a predetermined position for binding the first binding unit in a tilted posture to a retracted position outside the area occupied by the second binding unit that has reached the predetermined position. and a moving means , wherein the first binding unit performs stapleless binding in which corners of a sheet bundle are sandwiched between a pair of crimping teeth and bound by pressure without using a staple, and the sheet processing is performed. The apparatus includes a cleaner for cleaning at least one of the pair of crimping teeth of the first binding unit, the cleaner cleaning the movement trajectory of the pair of crimping teeth while the first binding unit swings. A cleaning member that contacts at least one of the pair of crimping teeth during swinging of the first binding unit at an intermediate position to scrape off paper dust adhering to the crimping teeth. Characterized by

Further, a moving means may be provided for moving the first binding unit in the tilted posture in parallel along the sheet width direction while maintaining the tilted posture.

Further, the moving means moves the first binding unit in the inclined posture to a first binding position for obliquely binding a corner portion of a first size sheet bundle, and a sheet width direction length larger than the first size. and a second binding position for obliquely binding the corner of a second size sheet bundle with a shorter width, and the second binding position is positioned in the sheet width direction relative to the first binding position. The swinging means swings the first binding unit in an inclined posture at the first binding position between the first and second binding positions to a retracted position. You can move it.

Also, the second binding unit may perform staple binding, in which a sheet bundle is bound using a staple.

Further, the first binding unit is arranged such that the main body and the head section including a pair of binding members for sandwiching and binding the sheet bundle are aligned in a direction orthogonal to the predetermined axis, and the first binding unit is arranged in a plane. It may be elongated in the direction in which the main body and the head portion are aligned when viewed.

Here, the predetermined shaft may be provided on the main body.

Here, the predetermined axis may be parallel to the direction orthogonal to the sheet surface of the corner of the sheet bundle.

Further, the retracted posture of the first binding unit at the retracted position may be a posture in which the longitudinal direction is parallel to the sheet conveying direction.

An image forming apparatus according to the present invention is an image forming apparatus that binds sheets on which images have been formed by the image forming section by a sheet processing section, and is characterized by including the above-described sheet processing apparatus as the sheet processing section. .

With the above configuration, the first binding unit in the inclined posture is swung to the retracted position before the second binding unit reaches the predetermined position. The space required for moving the first binding unit from the tilted posture to the retracted position can be reduced compared to the configuration in which the unit is moved in parallel in the direction away from the second binding unit while in the tilted posture, and the size of the device can be increased accordingly. can be suppressed.

1 is a schematic front view showing the overall configuration of an image forming apparatus; FIG. 4A to 4C are diagrams showing how a sheet is conveyed through a sheet processing unit; FIG. 2 is a schematic plan view of a sheet processing section; FIG. FIG. 4 is a perspective view of a binding unit that performs staple binding when viewed from the direction of arrow J in FIG. 3 ; FIG. 2 is a schematic perspective view of a binding unit that performs stapleless binding and a moving mechanism thereof, as viewed from the back side of the apparatus; 6 is an exploded perspective view of the binding unit, moving mechanism, and body frame shown in FIG. 5; FIG. (a) to (c) are plan views schematically showing how the binding unit transitions from the retracted position to the A4 binding position in an inclined posture to the B5 binding position. FIG. 3 is an exploded perspective view showing a specific configuration of a drive section; (a) is a side view of the binding unit when viewed from the direction of arrow D shown in FIG. 6, and (b) is an enlarged view showing a state in which a pair of crimping teeth sandwiches a sheet bundle. . 3 is a block diagram showing the configuration of a sheet processing control unit; FIG. 4 is a flowchart showing the contents of initial settings executed when power is turned on; 10 is a flow chart showing the contents of sheet corner binding processing. FIG. 10 is a plan view showing a state in which a binding unit that performs stapleless binding is retracted to a retracted position and a binding unit that performs staple binding is positioned at a corner binding position; FIG. 10 is a schematic perspective view of a cleaner that cleans crimping teeth of the binding unit located at the retracted position, viewed from the front side of the apparatus; (a) is a plan view schematically showing a configuration example in which the cleaning member is fixedly arranged, and (b) is the crimping teeth of the binding unit and the cleaning member at the time when the cleaning member is swung by an angle θa from the retracted position ( It is a side view when it sees from the arrow U direction shown to a). (a) is a schematic plan view for explaining a configuration example including two binding units for binding a sheet bundle, and (b) is a tilted posture of one of the binding units existing on the back side of the device shown in (a). FIG. 10 is a plan view showing an example of a case where the binding unit is moved in parallel to a retracted position on the back side of the apparatus in a direction away from the other binding unit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a sheet processing apparatus and an image forming apparatus including the sheet processing apparatus according to the present invention will be described below with reference to the drawings.

(1) Configuration of Image Forming Apparatus FIG. 1 is a schematic front view showing the overall configuration of an image forming apparatus 1, in which the horizontal direction is indicated by the X-axis direction, and the vertical direction is indicated by the Y-axis direction. Note that the depth direction orthogonal to both the X-axis and the Y-axis may be hereinafter referred to as the Z-axis direction.

As shown in the figure, the image forming apparatus 1 includes a scanner section 2, a printer section 3 located below the scanner section 2 and arranged across an internal space (hollow section) 7 having an opening on the front side of the apparatus, It is equipped with a sheet processing section 4 housed in an internal space 7, an operation section 5 arranged on the front side of the scanner section 2, and a main body control section 6, and executes various jobs and various functions. It is an internal discharge type multifunction device.

Various jobs include a scan job that scans the original image, a copy job that prints the image on a sheet based on the image data obtained by scanning the original image, and an external terminal (unknown) connected via the network. ), and prints an image related to the received job on a sheet. The various functions include a post-processing function for performing alignment, staple binding, and stapleless binding for a bundle of sheets after printing.

A scanner section (image reading section) 2 conveys a set document and reads an image of the document to obtain image data.

The printer unit 3 forms (prints) an image on a sheet based on image data obtained by the scanner unit 2 or data of a print job from an external terminal by electrophotography.

The printer unit 3 includes image forming units 11Y, 11M, 11C, and 11K having photosensitive drums 10Y, 10M, 10C, and 10K, an intermediate transfer belt 12, a paper feed cassette 13, an exposure unit 20, and the like.

The exposure unit 20 emits laser light for exposing and scanning the photosensitive drums 10Y to 10K based on image data of an image to be formed. The photosensitive drums 10Y to 10K are uniformly charged by the charging unit before the laser beam is emitted, and the surfaces of the charged photosensitive drums 10Y to 10K are exposed to the laser beam from the exposure unit 20 and are static. An electrostatic latent image is formed.

The electrostatic latent images formed on the photoreceptor drums 10Y to 10K of the imaging units 11Y to 11K are developed with toner in the developing units containing developer of corresponding colors. As a result, a Y (yellow) toner image is formed on the photosensitive drum 10Y, an M (magenta) toner image is formed on the photosensitive drum 10M, and a C (cyan) toner image is formed on the photosensitive drum 10C. , and a K (black) toner image is formed on the photosensitive drum 10K.

The Y to K toner images formed on the photosensitive drums 10Y to 10K are primarily transferred so as to be superimposed on the same position on the circulating intermediate transfer belt 12, respectively. As a result, a color toner image composed of Y to K toner images is formed on the intermediate transfer belt 12 .

The paper feed cassette 13 stores sheets S for recording, and the sheets S stored in the paper feed cassette 13 are delivered to the conveying path 19 one by one by a delivery roller 14 .

The sheet S delivered from the paper feed cassette 13 to the transport path 19 is transported upward to the secondary transfer roller 16 via the timing roller pair 15 .

The secondary transfer roller 16 is in contact with the intermediate transfer belt 12 at the secondary transfer position to form a transfer nip with the intermediate transfer belt 12. When the sheet S passes through the transfer nip, the secondary transfer roller 16 is in contact with the intermediate transfer belt 12. The color toner images on 12 are secondarily transferred to the sheet S collectively. Thereby, a color toner image is formed on the sheet S. As shown in FIG. The sheet S on which the color toner image has been formed is further conveyed to the upper fixing section 17 .

The fixing unit 17 heats and presses the color toner image on the sheet S after the secondary transfer to fix it to the sheet S. FIG. The sheet S that has passed through the fixing section 17 is sent to the sheet processing section 4 by a pair of discharge rollers 18 . Note that the printer unit 3 is not limited to the electrophotographic system, and may be, for example, an inkjet system.

The sheet processing unit 4 aligns a sheet bundle composed of a plurality of sheets discharged one by one from the discharge roller pair 18 of the printer unit 3, and binds the aligned sheet bundle, here, the first binding unit 101. , and stapleless binding by the second binding unit 102 are selectively performed. The bundle of sheets after the binding process is accommodated on the discharge tray 4a. A specific configuration of the sheet processing unit 4 will be described later.

The operation unit 5 is arranged at a position where the user can easily operate the image forming apparatus 1 when standing in front of the image forming apparatus 1. Input operations by the user, for example, input of the number of copies, an instruction to start a job such as copying, and an instruction to stop the job. Instructions, binding processing in the sheet processing unit 4, here, selection input of staple binding or stapleless binding, execution instruction of the selected binding processing, etc. are received, and the received contents are transmitted to the main body control unit 6.

The body control section 6 controls the scanner section 2 and the printer section 3 based on the input information from the user received by the operation section 5 to smoothly execute the job according to the user's instruction. Further, when execution of the binding process is instructed, the sheet processing unit 4 is made to execute the binding process.

(2) Configuration of Sheet Processing Unit 4 The sheet processing unit 4 includes a sheet conveying unit 41 , a sheet aligning unit 42 , a binding unit 43 including two binding units 101 and 102 , and a sheet processing control unit 44 .

The sheet conveying section 41 includes conveying roller pairs 411 , 412 and 413 , a discharge roller pair 414 and a flexible paddle 415 .

The transport roller pairs 411 , 412 , and 413 transport the sheets S output one by one from the discharge roller pair 18 of the printer section 3 on the transport path 40 in the sheet processing section 4 and send them to the discharge roller pair 414 . .

When the binding process is not performed, the sheet S sent to the discharge roller pair 414 is discharged to the outside of the apparatus as it is by the discharge roller pair 414 and is accommodated in the paper discharge tray 4a.

When performing the binding process on a sheet bundle composed of N (plural) sheets S, the sheets S sent one by one to the discharge roller pair 414 are arranged as shown in FIGS. be transported. That is, as shown in FIG. 2A, immediately before the transport direction trailing edge Se of the first sheet S passes through the discharge roller pair 414, the rotation direction of the discharge roller pair 414 rotates forward (in the direction indicated by the solid line). rotation) to reverse rotation (rotation in the direction indicated by the dashed line). By this reverse rotation, the sheet S is switched back, and the sheet S is conveyed toward the tray 420 of the sheet aligning section 42 with the trailing edge Se changed to the leading edge. Hereinafter, the front end Se of the sheet S will be referred to as the front end Se.

The tray 420 is slanted such that the other end on the far side is located below the one end on the side closer to the discharge roller pair 414 . In synchronism with the conveying of the sheet S onto the inclined tray 420, the paddle 415 rotates once in the direction shown in FIG. 2(b).

During this one rotation, the tip of the paddle 415 is in contact with the upper surface of the sheet S conveyed onto the tray 420 in a bent state, and a force along the rotation direction of the sheet S, that is, the sheet S is pushed to the lower end of the tray 420 . A force is applied in a direction directed toward the arranged stopper 424 .

Due to the conveying force applied from the paddle 415 and the inclination of the tray 420 , the sheet S on the tray 420 descends along the inclined surface of the tray 420 and stops when the leading edge Se hits the stopper 424 . The stopper 424 functions as an aligning unit that longitudinally aligns the sheet S in the conveying direction. After the sheet S is stopped, lateral alignment in the sheet width direction perpendicular to the sheet conveying direction (corresponding to the direction perpendicular to the plane of the drawing) is performed by a pair of alignment plates (not shown). Thus, the accommodation of the first sheet S on the tray 420 is completed.

For each sheet S after the second sheet S, the same series of operations as the switchback, vertical alignment, and horizontal alignment performed by the discharge roller pair 414 for the first sheet S are repeated, and each sheet S is placed on the tray 420. It will be loaded and accommodated. A sensor (not shown) is arranged near the discharge roller pair 414 to detect the sheets S conveyed onto the tray 420 by switchback. is counted.

When the Nth (last) sheet S is stacked and accommodated on the tray 420 , the binding unit designated by the user out of the binding units 101 and 102 of the binding section 43 binds the sheet bundle Sb on the tray 412 . binding process is executed. When the user instructs parallel binding with staples, the binding unit 101 is selected, and when the user instructs diagonal binding without staples, the binding unit 102 is selected.

When the binding process for the sheet bundle Sb is completed, the plate-like conveying member 425 contacts the leading end Se of the sheet bundle Sb as shown in FIG. move toward By the movement of the conveying member 425 , the sheet bundle Sb on the tray 420 is conveyed toward the discharge roller pair 414 . In synchronism with the transport of the sheet bundle Sb by the transport member 425, the discharge roller pair 414 is driven to rotate forward. , and stored on the discharge tray 4a.

FIG. 3 is a schematic plan view of the sheet processing section 4, showing the positional relationship among the tray 420, a pair of alignment plates 421 and 422 for lateral alignment, a stopper 424, a conveying member 425, and the binding units 101 and 102. showing. In this figure, the direction in which the sheet S is conveyed on the tray 420 is the sheet conveying direction, the width direction perpendicular to the sheet conveying direction is the sheet width direction, and the direction parallel to the sheet conveying direction and at the center of the sheet width direction on the tray 420 is A line passing through the positions is represented as a center line CL. The A4 size sheet bundle placed on the tray 420 is indicated by a solid line as Sb (A4), and the B5 size sheet bundle is indicated by a dashed line as Sb (B5).

Each time one sheet S is conveyed onto the tray 420, the pair of aligning plates 421 and 422 move from the home position indicated by the solid line to the aligning position corresponding to the size of the sheet S in the direction toward the center line CL. After moving, the operation of returning to the home position is repeated. For example, when the conveyed sheet S is A4 size (sheet width direction length is 297 mm), the alignment position (broken line position) is a position away from the center line CL by a distance La (=149 mm). When the conveyed sheet S is, for example, B5 size (sheet width direction length is 257 mm), the alignment position (the position of the dashed line) is a distance Lb (=129 mm) away from the center line CL.

The binding unit 101 performs parallel binding with a staple, and moves along the sheet width direction on rails 191 and 192 provided in the apparatus housing 45 by the driving force of a movement driving motor 190 .

FIG. 4 is a perspective view of the binding unit 101 when viewed from the direction of arrow J in FIG. 3, and also shows the sheet bundle Sb to be bound.

As shown in the figure, the binding unit 101 includes a housing 110 , a head section 111 and a staple cartridge 112 . Two guide pins 118 and 119 protruding downward are provided on the bottom portion 116 of the housing 110. The guide pins 118 and 119 travel along rails 191 and 192 shown in FIG. The unit 101 can move in the sheet width direction.

The head portion 111 is composed of a staple driving portion 121 and a staple receiving portion 122 which are arranged parallel to each other in the sheet width direction so as to face each other with a binding gap 123 interposed therebetween. With the side edge portion Sd of the sheet bundle Sb inserted into the binding gap 123, the staple driving portion 121 moves downward to feed the staples parallel to the sheet width direction from the staple driving portion 121. The staple receiving portion 122 is driven through the sheet bundle Sb. As a result, the aligned sheet bundle Sb is stapled (parallel binding with staples). The staple driving portion 121 and the staple receiving portion 122 serve as binding members. The needle driving section 121 is driven by the driving force of the needle driving section drive motor 117 . The staple cartridge 112 supplies staples to the staple driving section 121 .

The binding unit 101 is normally located on the front side of the device, and stands by at a home position (the position indicated by the solid line in FIG. 3) for performing parallel binding with staples on the corner St on the front side of the A4 size sheet bundle Sb. ing. When the binding unit 101 performs parallel binding with staples on a portion other than the corner St of the sheet bundle Sb, the binding unit 101 is moved along the sheet width direction so that the corner St of the sheet bundle Sb on the device front side is to the corner Su on the back side of the apparatus, a specified portion of the side edge Sd can be stapled. The home position detection sensor 193 (FIG. 3) detects that the binding unit 101 is at the home position.

Returning to FIG. 3, the binding unit 102 performs stapleless oblique binding at a predetermined binding position at one corner of the aligned sheet bundle Sb, here at the corner Su on the back side of the apparatus. It has an elongated shape. The binding unit 102 has a main body 120 and a head portion 130 having a pair of crimping teeth 131 and 132 (FIG. 9) as binding members arranged in the longitudinal direction.

The binding unit 102 is swingable about a swing shaft 129 provided in the main body 120 on the side opposite to the head portion 130 in the longitudinal direction between a retracted posture indicated by a dashed line and an inclined posture indicated by a solid line, and It is possible to move in parallel in the seat width direction between the position indicated by the solid line and the position indicated by the one-dot chain line while maintaining the tilted posture.

Here, the tilted posture is a posture in which the longitudinal direction of the binding unit 102 is tilted by a predetermined angle, here 45°, with respect to the sheet conveying direction. The position in the sheet width direction of the binding unit 102 in the inclined posture indicated by the solid line is the position for stapleless diagonal binding of the A4 size sheet bundle Sb (A4) on the tray 420 . The position in the sheet width direction of the binding unit 102 in the inclined posture indicated by the dashed line is the position for stapleless oblique binding with respect to the corner Su of the B5 size sheet bundle Sb (B5) on the tray 420. .

In this inclined posture, the direction of the tooth row of the crimping teeth 131 of the head portion 130 is inclined at 45° with respect to the sheet conveying direction. The crimping teeth 131 and 132 are separated vertically. The position of the binding unit 102 in the sheet width direction indicated by the solid line is called the A4 binding position, and the position of the binding unit 102 in the sheet width direction indicated by the dashed line is called the B5 binding position. The B5 binding position is closer to the sheet width direction center (CL) of the tray 420 in the sheet width direction than the A4 binding position.

The retracted posture indicated by the broken line is a posture in which the longitudinal direction of the binding unit 102 is parallel to the sheet conveying direction, and the head portion 130 of the binding unit 102 is retracted from the sheet bundle Sb on the tray 420 toward the back side of the apparatus. To switch the binding unit 102 from one of the retracted posture and the tilted posture at the A4 binding position to the other, swing the binding unit 102 about the swing shaft 129 in the direction of arrow A and in the direction of arrow B, which is the opposite direction. is done in

The swing shaft 129 is a predetermined shaft parallel to the direction perpendicular to the sheet surface of the corner Su of the sheet bundle Sb. The crimping teeth 131 and 132 swing along the sheet surface in a direction away from the corner Su of the sheet bundle Sb toward the back side of the apparatus, thereby making a transition to the retracted posture.

Such a posture change of the binding unit 102 is performed to prevent interference (collision) with the other binding unit 101 .

In order to prevent this interference, when the binding unit 101 executes a job of parallel binding the corner Su of the sheet bundle Sb, the binding unit 101 moving from the device front side toward the device back side is arranged to bind the corner portion Su on the device back side. (predetermined position for binding the corner Su), the binding unit 102 is shifted from the inclined posture to the retracted posture. This is because if the binding unit 101 is moved from the device front side to the device back side while the binding unit 102 is in the tilted posture, it will collide with the binding unit 102 during the movement.

Of course, the retracted posture is the posture (position) of the binding unit 102 that does not interfere with the binding unit 101 after reaching a predetermined position, and is determined in advance according to the sizes and shapes of the binding units 101 and 102 . Hereinafter, the position when the binding unit 102 is in the retracted posture may be referred to as the retracted position.

The reason why the mechanism for swinging the binding unit 102 is employed is to suppress the enlargement of the device. That is, as described in the section "Problems to be Solved by the Invention" above, the binding unit 102 in the tilted posture shown by the solid line is set so that the head portion 130 is positioned closer to the back side of the device than the corner Su of the sheet bundle Sb. 3, the corner 128 of the binding unit 102 on the back side of the binding unit 102 protrudes considerably toward the back side of the device with respect to the position shown in FIG. In this case, the rear cover 45a of the device housing 45 needs to be shifted to the rear side of the device from the position shown in FIG. 3, which increases the size of the device in the seat width direction. .

On the other hand, if a mechanism for swinging the binding unit 102 instead of parallel movement is adopted as in the present embodiment, even if the position of the corner 128 of the binding unit 102 in the sheet width direction is the retracted position as shown in FIG. It is possible to keep the A4 binding position from changing so much, and it is possible to suppress an increase in the size of the apparatus in the sheet width direction compared to a configuration in which parallel movement is performed.

For example, the distance from the side edge Sz on the back side of the A4 size sheet S placed on the tray 420 to the portion of the binding unit 102 in the retracted posture in the sheet width direction that is closest to the back side of the device is Lγ. Then, the distance Lγ becomes smaller than the distance Lβ shown in FIG. 16B showing an example of parallel movement. By the difference (=Lβ-Lγ), it can be seen that the swinging mechanism of the present embodiment can reduce the size of the device in the seat width direction more than the configuration of parallel movement. The binding unit 102 and the movement mechanism used to change the attitude and position of the binding unit 102 will be specifically described below.

(3) Moving Mechanism of Binding Unit 102 FIG. 5 is a schematic perspective view of the binding unit 102 and its moving mechanism 103 as seen from the rear side of the device, including the body frame 90 fixed to the device housing 45. is shown. The moving mechanism 103 includes a driving portion 151 and a support plate 152, and the body frame 90 includes a plate-like base 91 and a plate-like guide member 92 having a greater thickness than this.

FIG. 6 is an exploded perspective view of the binding unit 102, the moving mechanism 103, and the body frame 90 shown in FIG. , the binding unit 102 is positioned from top to bottom in this order.

A plate-shaped base 91 is provided with three elongated holes (through holes) 93, 94, and 95 elongated in the Z-axis direction and arranged in this order in the X-axis direction. The guide member 92 also has an elongated hole (through hole) 89 extending linearly in the Z-axis direction. Longitudinal end portions 89a and 89b of the long hole 89 are arcuate in plan view. Each of the elongated holes 94 and 89 is parallel to the Z-axis (seat width direction) and has substantially the same size. are fixed to the lower surface of the base 91 with screws or the like. A dashed line 96 shown in FIG. 10 indicates an imaginary outline of a region of the lower surface of the base 91 to which the guide member 92 is fixed.

The drive unit 151 is rotatable on a top plate 170 , a rod 171 extending downward from the bottom surface of the top plate 170 , a fixed shaft 172 , and a bearing 181 whose upper end is fitted in a through hole 180 of the top plate 170 . and a rotating shaft 173 supported by the .

A lower end 174 of the rod 171 is fitted into a hole 71 provided in the support plate 152 through the elongated hole 93 of the base 91 and fixed to the support plate 152 with an adhesive or the like. The fixed shaft 172 has a circular cross section, and its lower end 176 passes through the elongated hole 94 of the base 91 and the elongated hole 89 of the guide member 92 and is fitted into the hole 73 provided in the support plate 152. It is fixed to the support plate 152 with . A lower end 179 of the rotary shaft 173 passes through an elongated hole 95 of the base 91 and is rotatably supported by a bearing 75 fitted in a hole 72 of the support plate 152 .

The binding unit 102 is fixed to the support plate 152 by, for example, screwing the top plate 105 to the lower surface of the support plate 152 .

In this manner, the binding unit 102 and the drive section 151 are integrally supported via the support plate 152 while maintaining a constant distance from the body frame 90 .

A cylindrical collar 175 that engages with the elongated hole 89 of the guide member 92 is rotatably fitted on the fixed shaft 172 at a position slightly above the lower end 176 of the fixed shaft 172 . Here, the outer diameter of the collar 175 is substantially equal to the width of the elongated hole 89 of the guide member 92 , and the collar 175 is fitted in the elongated hole 89 of the guide member 92 and freely moves along the elongated hole 89 . can be moved to

A spur gear 209 is fitted at a position slightly above the lower end 179 of the rotating shaft 173 so as not to rotate with respect to the rotating shaft 173 . The rotary shaft 173 is rotated by a rotational driving force of a drive motor 201 (FIG. 8), which will be described later, and the rotation of the rotary shaft 173 causes the spur gear 209 to rotate integrally with the rotary shaft 173 in the same direction.

The spur gear 209 is meshed with a rack 80 provided on the outer edge of the guide member 92 . The rack 80 has a linear portion 81 along the elongated hole 89 and an arc portion 82 continuous therewith. The arc portion 82 of the rack 80 and the arc-shaped end portion 89a of the long hole 89 which is closer to the arc portion 82 are in a concentric relationship centering on the axis of the fixed shaft 172. .

With the collar 175 of the fixed shaft 172 positioned at the end portion 89a of the elongated hole 89 of the guide member 92, the spur gear 209 meshing with the rack 80 rotates in the direction of arrow E to rotate from the arc portion 82 of the rack 80 to the linear portion. 81 , the drive unit 151 rotates in the direction of arrow A about the fixed shaft 172 with respect to the body frame 90 integrally with the support plate 152 and the binding unit 102 , and then moves along the long hole 89 with the arrow C. It moves linearly in the direction (equivalent to the sheet width direction).

The rotary motion before this linear motion corresponds to the motion of swinging the binding unit 102 from the retracted posture (broken line) shown in FIG. 2 corresponds to the operation of moving in parallel from the A4 binding position (solid line) to the B5 binding position (chain line). In this sense, the moving mechanism 103 of the binding unit 102 functions as a moving means for parallelly moving the binding unit 102 in the tilted posture along the sheet width direction while maintaining the tilted posture.

FIGS. 7A to 7C are plan views schematically showing how the binding unit 102 transitions from the retracted position to the A4 binding position in an inclined posture to the B5 binding position, to facilitate understanding of the description. Therefore, only the guide member 92, the support plate 152, the head portion 130 of the binding unit 102, and the spur gear 209 are shown.

FIG. 7A shows a case where the binding unit 102 is at the retracted position, the binding unit 102 is parallel to the sheet conveying direction, and the head section 130 is closer to the back of the apparatus than the sheet bundle Sb. side, and the sheet bundle Sb cannot be staple-less bound. Here, the side surfaces 106 and 107 of the main body 120 of the binding unit 102 are substantially flat surfaces, and the side surfaces 106 and 107 are parallel to the sheet conveying direction at the retracted position.

Further, when the binding unit 102 is retracted to the retracted position, the spur gear 209 of the drive section 151 is engaged with the arc section 82 of the rack 80 of the guide member 92, and the collar fitted on the fixed shaft 172 is engaged. 175 is located at the end 89a of the elongated hole 89 of the guide member 92. As shown in FIG.

As described above, the arc portion 82 of the rack 80 and the arc-shaped end portion 89a of the elongated hole 89 form a concentric circle centered on the axis of the fixed shaft 172. As shown in FIG. Then, the supporting plate 152 and the binding unit 102 are fitted to the stationary guide member 92 fixed to the base 91 as described above, and the rotating shaft 173 to which the spur gear 209 is fitted and the collar 175 are fitted. It is configured to move integrally with the fixed shaft 172 .

Therefore, when the spur gear 209 starts rotating in the direction of arrow E and moves toward the linear portion 81 along the arc portion 82 of the rack 80, the rotation shaft 173 in which the spur gear 209 is fitted is rotated. As a result, a force that rotates in the direction of arrow A about the axis of the fixed shaft 172 acts on the driving portion 151 . Due to the action of this force, the binding unit 102 integrated with the drive section 151 via the support plate 152 starts swinging in the arrow F direction about the axis (predetermined axis) of the fixed shaft 172 . The axis of this fixed shaft 172 corresponds to the swing shaft 129 (FIG. 3) of the binding unit 102 .

When the binding unit 102 swings, a rotatable roller member 155 erected on the support plate 152 is guided along the curved surface portion 88 of the guide member 92 on the opposite side of the rack 80 in plan view. As a result, the rocking motion can be performed smoothly.

When the binding unit 102 at the retracted position is swung from the retracted position by an angle of 45° in the direction of arrow F about the axis of the fixed shaft 172, the head portion 130 of the binding unit 102 is shown in FIG. 7B. is tilted at 45° with respect to the sheet conveying direction. At this time, the spur gear 209 has moved to the boundary between the arc portion 82 and the linear portion 81 of the rack 80 . The position of the binding unit 102 shown in FIG. 7B is the A4 binding position, and the corner Su of the A4 size sheet bundle Sb (A4) on the tray 420 can be stapleless obliquely bound.

Further, when the rotation of the spur gear 209 continues and the spur gear 209 begins to move along the linear portion 81 of the rack 80, the distance between the rotating shaft 173 and the fixed shaft 172 is constant, and the guide member 92 is moved to the base 91. 173 to which the spur gear 209 is fitted. direction).

Due to the action of this force, the binding unit 102 integrated with the drive unit 151 via the support plate 152 moves along the direction of the arrow C with respect to the guide member 92 while being inclined at 45 degrees with respect to the sheet conveying direction. Start moving in a straight line, that is, moving parallel. After starting parallel movement, the binding unit 102 moves parallel by δ (=20) mm from the position corresponding to the B5 size sheet bundle Sb (B5) as shown in FIG. At the binding position, the corner Su of the B5 size sheet bundle Sb (B5) on the tray 420 can be staple-less obliquely bound. Note that the spur gear 209 can be reversed to return the binding unit 102 from the B5 binding position through the A4 binding position to the retracted posture.

Thus, the spur gear 209 and the guide member 92 function as means for switching the retracted posture and the inclined posture of the binding unit 102 and the A4 binding position and the B5 binding position, respectively. Next, a rotation drive mechanism for the spur gear 209 in the drive section 151 will be described.

(4) Configuration of Drive Unit 151 FIG. 8 is an exploded perspective view showing a specific configuration of the drive unit 151, in which the top plate 170 is removed and the rod 171 is omitted.

As shown in the figure, the drive unit 151 includes a drive motor 201, a gear 201a mounted on the rotary shaft of the drive motor 201, a gear 202 rotatably fitted on the rotary shaft 202a and meshing with the gear 201a, and a rotary shaft. A gear 203 fitted to one end of 204 and meshing with gear 202, a cylindrical worm 205 fitted to the other end of rotary shaft 204, and a fixed shaft 172 rotatably fitted, A worm wheel 206 meshing with a worm 205, a gear 208 fitted on a rotating shaft 173 and meshing with the worm wheel 206, and a spur gear 209 fitted on the rotating shaft 173 at a position slightly below the gear 208. have.

The gear 203 and the worm 205 are fixed to the rotating shaft 204 and rotate integrally with the rotating shaft 204 in the same direction. The gear 208 and the spur gear 209 are fixed to the rotating shaft 173 and rotate together with the rotating shaft 173 in the same direction.

When the driving motor 201 rotates forward, here the gear 201a fitted to the rotating shaft rotates in the direction of arrow P, the rotational driving force of the driving motor 201 is transferred to the gears 202, 203, rotating shaft 204, worm 205, worm wheel 206, The power is transmitted to the spur gear 209 via the gear 208 and the rotating shaft 173, and the spur gear 209 rotates in the arrow E direction. Each gear from gear 201 a to gear 208 and rotary shafts 204 and 173 constitute a drive transmission mechanism 200 that transmits the rotational driving force of drive motor 201 to spur gear 209 .

When the drive motor 201 rotates in the reverse direction, that is, when the gear 201a rotates in the direction opposite to the direction of the arrow P, rotational driving force in the direction opposite to that during forward rotation is transmitted from the drive motor 201 to the spur gear 209 via the drive transmission mechanism 200. , the spur gear 209 rotates in a direction opposite to the arrow E direction.

In the present embodiment, as will be described later, by grasping how much the drive motor 201 has rotated based on when the binding unit 102 is at the retracted position, the binding unit 102 moves from the retracted position to the A4 binding position or the B5 binding position. It is configured to determine that a transition to the binding position has occurred. The drive unit 151 is provided with a detection unit 210 that detects the rotation angle (total amount of rotation) of the drive motor 201 .

The detection unit 210 includes a rotating shaft 211 , a gear 212 fitted on the rotating shaft 211 and meshing with the worm wheel 206 , a circular plate to be detected 213 fitted on the rotating shaft 211 , and a rotation amount detection sensor 214 . include.

The rotating shaft 211 has an upper end rotatably supported by the top plate 170 ( FIG. 6 ) and a lower end rotatably supported by a support member (not shown) provided in the drive section 151 . The gear 212 and the plate 213 to be detected are fixed to the rotary shaft 211. When the gear 212 rotates due to the rotation of the worm wheel 206, the plate 213 to be detected rotates integrally with the gear 212 in the same direction.

The rotation amount detection sensor 214 is a transmissive optical sensor having a light emitting portion 221 and a light receiving portion 222. When the light emitted from the light emitting portion 221 is received by the light receiving portion 222, an electric signal corresponding to the amount of received light is generated. , here outputs a signal of H or L level.

The plate 213 to be detected is arranged at a position such that its outer peripheral portion 215 enters the detection space 223 between the light emitting portion 221 and the light receiving portion 222. Notches 231 and 232 are provided at two positions. While the plate 213 to be detected rotates once in the direction of the arrow Ea, one of the plate portions 215a, 215b, 215c other than the cutouts 231, 232 of the outer peripheral portion 215 is positioned between the light emitting portion 221 and the light receiving portion 222. When interposed in the detection space 223 , the light emitted from the light emitting section 221 is blocked by the plate portion, so that it is not received by the light receiving section 222 . In this case, the rotation amount detection sensor 214 outputs an L level signal. On the other hand, when one of the cutout portions 231 and 232 of the outer peripheral portion 215 is interposed in the detection space 223, the light emitted from the light emitting portion 221 is emitted into the space between the plate portions 215a and 215b or the plate portions 215b and 215c. passes through the space between and is received by the light receiving section 222 . In this case, the rotation amount detection sensor 214 outputs an H level signal.

Here, when the binding unit 102 is stationary at the retracted position due to the stoppage of the drive motor 201, the plate 213 to be detected is also stationary. It is detected and an L level signal is output from the rotation amount detection sensor 214 .

When the driving motor 201 starts rotating and the detected plate 213 starts rotating in the direction of the arrow Ea, the edge 215d of the plate portion 215a of the detected plate 213 passes through the detection space 223 of the rotation amount detection sensor 214. FIG. Due to the passage of this edge 215d, the output signal of the rotation amount detection sensor 214 is switched from the L level to the H level. After this, the drive motor 201 continues to rotate, and after the edge 215e of the plate portion 215b of the plate 213 to be detected passes through the detection space 223 of the rotation amount detection sensor 214, the edge 215f passes next. As the edges 215e and 215f pass in order, the output signal of the rotation amount detection sensor 214 changes from H level to L level and then to H level again.

That is, after the drive motor 201 starts rotating, the output signal of the rotation amount detection sensor 214 is monitored. Switching to the H level is detection of the notch portion 232 . The detection of this level switching is substantially the detection of the total amount of rotation from the start of rotation of the drive motor 201 .

The first cutout portion 231 is detected when the binding unit 102 swings from the retracted position to the A4 binding position, and the second cutout portion 231 is detected when the binding unit 102 moves parallel to the B5 binding position through the A4 binding position. If the formation positions of the notches 231 and 232 on the plate 213 to be detected are determined in advance, the output signal of the rotation amount detection sensor 214 is monitored so that the binding unit 102 moves from the retracted position to the A4 binding position. Movement and movement from the retracted position to the B5 binding position via the A4 binding position can be detected.

Note that the movement of the binding unit 102 starts from the retracted position, which is a reference, and does not start from the retracted position. When moving to the B5 binding position (or the A4 binding position), the binding unit 102 is once returned to the retracted position. After that, the binding unit 102 at the retracted position is moved to the A4 binding position (or the B5 binding position). By detecting the amount of movement from the reference retracted position, it is possible to improve the positioning accuracy of the A4 binding position and the B5 binding position.

Detection that the binding unit 102 is positioned at the retracted position is performed by a retracted position detection sensor 154 (Fig. 6) is detected.

(5) Drive Mechanism of Binding Unit 102 FIG. 9A is a side view of the binding unit 102 as viewed in the direction of arrow D shown in FIG. As shown in FIG. 9A , the binding unit 102 includes a head section 130 and a drive section 135 that drives the head section 130 . The head portion 130 includes a pair of crimping teeth 131 and 132 , an upper tooth supporting member 133 fixedly supporting the upper crimping tooth 131 , and a lower tooth supporting member 134 fixingly supporting the lower crimping tooth 132 .

The drive unit 135 includes arms 141 and 142, a swing shaft 143, a cam 144, a compression coil spring 145, and a crimp tooth drive motor 146, and is supported by a housing 139 of the main body 120.

One longitudinal end of the arm 141 is connected to the upper tooth supporting member 133 , and the other longitudinal end of the arm 141 is provided with a pin 147 that abuts on the peripheral surface of the cam 144 .

The swing shaft 143 is provided at a position closer to the center in the longitudinal direction of the arm 141. The arm 141 is attached to the housing 139 via the swing shaft 143, and the arrow H shown in FIG. It is supported so that it can swing in any direction.

The cam 144 is a plate-like cam having a substantially semicircular shape when viewed from the side. By being transmitted, it rotates around the rotating shaft 148 . The rotation of the cam 144 , which has a different cam diameter depending on the rotation angle, applies force to the pin 147 of the arm 141 contacting the peripheral surface of the cam 144 to swing the arm 141 . It should be noted that a compression spring (non-contact spring) that applies an urging force to the arm 141 to urge the pin 147 of the arm 141 toward the peripheral surface of the cam 144 so that the pin 147 of the arm 141 is always in contact with the peripheral surface of the cam 144 . shown) are arranged.

The arm 142 has a portion near the center in the longitudinal direction connected to the lower tooth support member 134 , one end in the longitudinal direction is oscillatably supported by the oscillating shaft 143 , and the other end is connected to the housing 139 via the compression coil spring 145 . supported by The drawing shows a case where the compression coil spring 145 is in a natural length state. The reason for providing the compression coil spring 145 will be described later.

In such a configuration, when the cam 144 is stopped at the home position (where the rotation angle is assumed to be 0°) shown in the figure, the upper crimping teeth 131 move vertically with respect to the lower crimping teeth 132. The farthest position, that is, the distance between the pair of crimping teeth 131 and 132 is maximized. The state in which the separation distance between the crimping teeth 131 and 132 is maximized is the state in which the sheet bundle Sb can be received, and the sheet bundle Sb is conveyed onto the tray 420 to the space 138 between the crimping teeth 131 and 132 with the maximum clearance. The corner Su of the incoming sheet bundle Sb is inserted.

While the cam 144 starts rotating from the home position and rotates up to 180°, force continues to act on the pin 147 of the arm 141 from the cam 144 in the direction away from the rotating shaft 148 of the cam 144 . As a result, the arm 141 swings about the swing shaft 143 in the arrow I direction.

Due to this swinging of the arm 141 , the upper crimp tooth 131 descends toward the lower crimp tooth 132 via the upper tooth support member 133 connected to one end of the arm 141 . As a result, as shown in FIG. 9B, the upper crimping teeth 131 sandwich the sheet bundle Sb and press the lower crimping teeth 132, thereby performing stapleless binding.

The stapleless binding is performed by deforming the sheets S so that the fibers of the sheets S constituting the sheet bundle Sb are entangled with each other by the crimping teeth 131 on the upper side and the crimping teeth 132 on the lower side. requires a fairly strong crimping force.

This strong crimping force is achieved by increasing the swinging force from the cam 144 to the arm 141. Due to the strong crimping force, even if the sheet bundle Sb is sandwiched therebetween, the tip of the crimping tooth 131 on the upper side and the lower side of the crimping tooth 131 are not in contact with each other. If this continues every time the stapleless binding is performed, the wear of the crimping teeth 131 and 132 is likely to progress.

Therefore, in this embodiment, when the upper crimping teeth 131 press the lower crimping teeth 132, a compression coil spring 145 is provided that is slightly compressed and deformed by the pressing force received by the lower crimping teeth 132. The compression deformation of the coil spring 145 allows the lower crimping teeth 132 to move in the direction (downward) away from the upper crimping teeth 131 .

As a result, the crimping teeth 131 and 132 can be prevented from directly contacting and being worn, as compared with a configuration in which the crimping teeth 132 on the lower side do not move downward at all (does not allow escape of the crimping teeth 132). progress of wear can be suppressed.

After the stapleless binding, the cam 144 is reversely rotated to return to the home position (rotational angle of 0°), so that the separation distance between the pair of crimping teeth 131 and 132 is maximized, that is, the sheet bundle Sb can be received. can go back.

(6) Configuration of Sheet Processing Control Unit 44 FIG. 10 is a block diagram showing the configuration of the sheet processing control unit 44. As shown in FIG.

As shown in the figure, the sheet processing control section 44 includes an instruction section 440 , a first control section 441 and a second control section 442 . The instruction unit 440 performs the initial setting when the image forming apparatus 1 is powered on, and the binding processing according to the binding processing request received from the main body control unit 6 for each job. The controller 442 is instructed.

Here, the binding processing request includes the size (here, A4, B5) and the number of sheets to be bound, the binding method (here, with staple or without staple), the binding position (here, sheet corner St, In the case of other than Su and the corner, the distance from the reference corner St, etc.) are included.

The first control unit 441 controls the binding unit 101 that performs parallel binding with staples. Specifically, when receiving an initial setting execution instruction from the instruction unit 440, the movement drive motor 190 is controlled to return the binding unit 101 to the home position (FIG. 3). Whether or not the binding unit 101 is at the home position is determined by the detection result indicating whether or not the binding unit 101 is at the home position by the home position detection sensor 193 .

After that, when the first control unit 441 receives an execution instruction of the staple binding process for each job from the instruction unit 440, the first control unit 441 controls the movement drive motor 190 to perform the instructed binding operation of the binding unit 101 located at the home position. Move only the distance required to move to the position. Then, when the binding unit 10 moves to the binding position, the staple driving unit driving motor 117 is controlled to perform parallel binding with the staple on the sheet bundle Sb. As for the binding process for the corner Su on the back side of the apparatus in the sheet bundle Sb, the moving distance from the home position to the predetermined position for binding the corner Su is determined in advance for each sheet size, and only that distance is determined. This is done by moving the binding unit 101 . In this manner, the binding unit 101 can selectively perform parallel binding with staples at different locations including the corner Su of the sheet bundle Sb.

Further, when the first control unit 441 receives an execution instruction of staple-attached parallel binding to the corner Su of the sheet bundle Sb for each job, the first control unit 441 adjusts the corner Su of the sheet bundle Sb of the binding unit 101 located at the home position. information (corner binding information) indicating the start of staple binding to the corner Su is sent to the second control unit 442 to perform staple binding to the corner Su. It notifies the second control section 442 to start moving the unit 101 . After that, when the retraction completion information indicating that the retraction to the retraction position of the binding unit 102 is completed is received from the second control unit 442, the movement of the binding unit 101 is started.

The second control unit 442 controls the binding unit 102 that performs stapleless oblique binding. Specifically, when an initial setting execution instruction is received from the instruction unit 440, the driving motor 201 is controlled to move the binding unit 102 to the A4 binding position. The movement to the A4 binding position is performed by first returning the binding unit 102 to the reference retracted position and then swinging it to the A4 binding position. The determination that the binding unit 102 has returned to the retracted position is made based on the detection result of the retracted position detection sensor 154, and the determination of the transition from the retracted position to the A4 binding position of the binding unit 102 is based on the detection of the rotation amount detection sensor 214. This is done according to the result (detection of the first L-level to H-level switch described above).

Thereafter, when the second control unit 442 receives an instruction to perform stapleless oblique binding of the A4 size sheet bundle Sb from the instruction unit 440, the second control unit 442 executes the binding process with the binding unit 102 at the A4 binding position as it is. When an instruction to execute stapleless oblique binding is received for a sheet bundle Sb of B5 size instead of A4 size, the binding unit 102 is once returned to the retracted position, moved to the B5 binding position via the A4 binding position, and then B5. The stapleless oblique binding is applied to the sheet bundle Sb of the size. The transition from the retracted position of the binding unit 102 to the B5 binding position is determined based on the detection result of the rotation amount detection sensor 214 (detection of switching from the L level to the H level for the second time).

When performing staple-less oblique binding, the crimping tooth drive motor 146 is controlled to pinch the sheet portion of the corner Su of the sheet bundle Sb with a strong force between the crimping teeth 131 and 132 of the binding unit 102, thereby binding the sheet portion. crimp.

Further, when the second control unit 442 receives the corner binding information from the first control unit 441, the second control unit 442 moves the binding unit 102 currently existing at the A4 binding position from the front side to the back side of the apparatus for execution of parallel binding with staples. In order to prevent interference with the moving binding unit 101, the binding unit 102 is retracted from the A4 binding position to the retracted position. This retraction is performed before the binding unit 101 reaches a predetermined position (corner binding position) for binding the corner Su of the sheet bundle Sb. When judging from the detection result of the retraction position detection sensor 154 that the binding unit 102 has retracted to the retraction position, the second control section 442 sends retraction completion information to the first control section 440 to that effect.

(7) Initial Settings by Sheet Processing Control Unit 44 and Details of Sheet Corner Binding Process for Binding Corner Su of Sheet Bundle FIG. 11 is a flowchart showing the details of the initial settings executed when the power is turned on. As shown in the figure, the first controller 441 first moves the binding unit 101 to the home position (step S1). After the binding unit 101 moves to the home position, the second control unit 441 moves the binding unit 102 to the A4 binding position (step S2), and ends the initial setting. With this initial setting, the binding unit 101 is positioned at the home position and the binding unit 102 is positioned at the A4 binding position when the first job is executed after the power is turned on. The reason why the initial setting position of the binding unit 102 is the A4 binding position is that, of the A4 and B5 sizes, the A4 size is generally used more frequently than the B5 size. Under certain circumstances, the binding position may be changed to B5.

FIG. 12 is a flow chart showing the details of the sheet corner binding process. This sheet corner binding process is executed when the binding process for the corner Su of the sheet bundle Sb on the back side of the apparatus is instructed for each job.

As shown in the figure, first, it is determined whether the binding is stapleless binding or staple binding (step S11). When it is determined that the stapleless binding is performed ("Yes" in step S11), it is determined whether or not the size of the sheets S to be bound is A4 size (step S12). If it is determined to be A4 size ("Yes" in step S12), the binding unit 102 existing at the A4 binding position is used to execute stapleless diagonal binding processing for the corner Su of the A4 size sheet bundle Sb (step S14), Go to step S15.

On the other hand, if it is determined that the size of the sheets S to be bound is not A4 size but B5 size ("No" in step S12), the binding unit 102 located at the A4 binding position is moved to the B5 binding position (step S13), Using the binding unit 102, the corner Su of the B5 size sheet bundle Sb is staple-less obliquely bound (step S14), and the process proceeds to step S15.

In step S15, the binding unit 102 that has completed the stapleless oblique binding is returned to the A4 binding position, and the process ends. Note that if the binding unit 102 is actually at the A4 binding position, the processing ends. Since the binding unit 102 is returned to the A4 binding position in step S15, the binding unit 102 remains at the A4 binding position when the next job is started.

When it is determined that it is parallel binding with staples instead of stapleless binding ("No" in step S11), the first control unit 441 transmits corner binding information to the second control unit 442 (step S16). . Upon receiving the corner binding information, the second control unit 442 retracts the binding unit 102 at the A4 binding position to the retracted position (step S17), and when the retraction is completed, transmits retraction completion information to the first controller 441. (step S18).

The first control unit 441 that has received the retraction completion information moves the stationary binding unit 101 from the home position to the planned binding position, here the corner binding position, that is, the corner Su of the sheet bundle Sb for parallel binding with the staple. (step S19).

FIG. 13 is a plan view showing how the binding unit 102 is retracted to the retracted position and the binding unit 101 is positioned at the corner binding position. As shown in the figure, the retracted position of the binding unit 102 is located outside the area occupied by the stitching unit 101 positioned at the corner binding position (outer frame 101a indicated by the solid line). Interference with the binding unit 101 that has moved to the part binding position is prevented. In this sense, the second control unit 442 and the moving mechanism 103 of the binding unit 102 move the binding unit 102 in the tilted posture before the binding unit 101 reaches the corner binding position. functions as a swing means for swinging to a retracted position outside the area 101a occupied by .

Returning to FIG. 12, in step S20, the binding unit 101 is used to perform parallel binding with a staple on the corner Su of the sheet bundle Sb. When the parallel binding with staples is completed, the binding unit 101 is returned to the original home position (step S21), and the process proceeds to step S15. As a result, the binding unit 102 at the retracted position is also returned to the original A4 binding position. After that, the process ends.

As described above, in the present embodiment, the binding unit 102 is configured to be swingable about the swing shaft 129 from the A4 binding position to the retracted position. Compared to a configuration in which the device is moved in parallel to the rear side of the device and retracted immediately, it is possible to reduce the size of the device in the sheet width direction.

Further, when the binding unit 102 is retracted to the retracted position, the head section 130 of the binding unit 102 is positioned closer to the back side of the apparatus than the tray 420, so that the back cover 45a (FIG. 3) of the apparatus housing 45 can be removed. , the service person can immediately access the head section 130 from the rear side of the apparatus. This facilitates maintenance of the crimping teeth 131 and 132 of the head portion 130 .

The present invention is not limited to the image forming apparatus, and may be a sheet processing unit (apparatus) attached to the image forming apparatus. Alternatively, it may be a method of moving the binding unit executed by the image forming apparatus or the sheet processing apparatus. Furthermore, the method may be a program executed by a computer. Further, the program according to the present invention can be, for example, a magnetic disk such as a magnetic tape or a flexible disk, an optical recording medium such as a DVD-ROM, a DVD-RAM, a CD-ROM, a CD-R, an MO, or a PD, or a flash memory type recording medium. etc., can be recorded on various computer-readable recording media, and may be produced, transferred, etc. in the form of such recording media, or in the form of programs, various wired and wireless networks including the Internet, It may be transmitted and supplied via broadcasting, electric communication lines, satellite communication, or the like.

(8) Modifications Although the present invention has been described above based on the embodiments, the present invention is of course not limited to the above-described embodiments, and the following modifications are conceivable.

(8-1) In the above embodiment, no particular reference was made to the configuration for cleaning the crimping teeth 131 and 132 of the binding unit 102, but it is also possible to adopt a configuration in which this is provided. If paper dust generated from the paper during crimping continues to accumulate on the tooth flanks and tooth bottoms of the crimping teeth 131 and 132 as crimping members, the meshing of the crimping teeth 131 and 132 may become poor and the crimping force at the binding portion may decrease. It is from.

FIG. 14 is a schematic perspective view of the cleaner 300 cleaning the crimping teeth 131 and 132 of the binding unit 102 positioned at the retracted position, viewed from the front side of the apparatus.

As shown in the figure, the cleaner 300 includes a cleaning member 301 and a cleaning drive section 302 .

The cleaning member 301 is composed of a thin plate 311 and a large number of resin or metal brush bristles 312 planted on both sides thereof.

The cleaning drive unit 302 is a direct-acting stepping motor, and includes a main body 321 containing a rotor (not shown) that is a female screw, and a shaft 322 that is a ball screw that is a male screw that is screwed to the rotor. The motion is converted to linear motion along the length of shaft 322 . Shaft 322 never rotates. The main body 321 is fixedly arranged so as not to move with respect to the device housing 45 .

A cleaning member 301 is connected to the tip of the shaft 322 . The cleaning driver 302 is controlled by a second controller 442 (FIG. 10).

Specifically, the second control unit 442 causes the cleaning member 301 to wait at a standby position that does not interfere with the swinging of the binding unit 102 when it is not the predetermined timing for cleaning the crimping teeth 131 and 132 .

When the predetermined timing for cleaning the crimping teeth 131 and 132 is reached, the second control section 442 moves the shaft 322 of the cleaning drive section 302 in the direction of the arrow Q to move the cleaning member 301 from the standby position to the crimping teeth 131 . , 132 to a cleaning position in the space 138 between them. Since the distance required for the cleaning member 301 to move from the standby position to the cleaning position is predetermined, the cleaning drive unit 302 is instructed to move the shaft 322 in the arrow Q direction by that distance.

By moving the cleaning member 301 to the cleaning position, the paper dust adhering to the pressing teeth 131 and 132 is scraped off by the bristles 312 of the cleaning member 301 . The scraped paper dust falls under its own weight and is collected in a disposal container 303 arranged below the binding unit 102 . After cleaning the crimp teeth, the shaft 322 is moved in a direction opposite to the arrow Q direction to return the cleaning member 301 from the cleaning position to the standby position.

The second control unit 442 shifts the binding unit 102 from the A4 binding position to the retracted position every time a predetermined timing for cleaning the crimp teeth comes, and then moves the cleaning member 301 from the standby position to the cleaning position. After that, the operation of returning to the standby position is repeated once or multiple times. As a result, it is possible to prevent paper dust from continuously accumulating on the crimping teeth 131 and 132 . After cleaning, the second control unit 442 returns the binding unit 102 from the retracted position to the original A4 binding position.

The predetermined timing is determined in advance by experiment or the like. For example, every time the cumulative execution count of stapleless diagonal binding by the binding unit 102 reaches a predetermined number of times (a multiple of 100, etc.), or for a type of paper that tends to generate paper dust (such as a log paper), stapleless diagonal binding is executed. degree, etc. Since the brush bristles 312 of the cleaning member 301 are brought into contact with the crimping teeth 131 and 132 only when the crimping teeth need to be cleaned, the number of times of contact of the brush bristles 312 with the crimping teeth 131 and 132 can be limited, and the contact frequency is increased. It is possible to suppress the wear of the brush bristles 312 from being excessively increased.

The condition for executing the cleaning of the crimp teeth is not limited to when a predetermined timing is reached, for example, when an execution instruction is received from the user, specifically, when the user issues a cleaning execution instruction from the operation unit 5. can also be

In the above description, the configuration example in which the cleaning member 301 has the brush bristles 312 planted on both sides of the thin plate 311 has been described, but the configuration is not limited to this. For example, if a large amount of paper dust adheres to one of the crimping teeth 131 and 132, the brush bristles 312 are applied only to the surface of the thin plate 311 corresponding to that crimping tooth. It is also possible to adopt a configuration in which they are provided. Further, the cleaning member 301 is not limited to the thin plate 311, and may be a rod-shaped member having brush bristles provided at its tip.

Furthermore, although an example of using a direct-acting motor as a drive mechanism for advancing and retreating the cleaning member 301 with respect to the crimping teeth 131 and 132 has been described, the present invention is not limited to this. etc. can also be used.

(8-2) In the modified example (8-1), the cleaning member 301 is movable forward and backward relative to the crimping teeth 131 and 132, but the present invention is not limited to this. For example, while the binding unit 102 swings between the retracted position and the A4 binding position, the moving crimping teeth 131 and 132 are brought into contact with and cleaned at a position midway along the moving locus of the crimping teeth 131 and 132 . A configuration in which the cleaning member is fixedly arranged on the apparatus housing 45 can also be adopted.

FIG. 15A is a plan view schematically showing a structural example in which the cleaning member 331 is fixedly arranged. In the figure, only the members necessary for explaining the cleaning mechanism of the crimping teeth 131 and 132 are shown. A part of 102 is virtually indicated by a one-dot chain line, and a movement locus 335 of the crimping teeth 131 and 132 is indicated by a two-dot chain line.

As shown in the figure, the cleaning member 331 is swung by an angle θa in the swinging direction (direction of arrow A) with respect to the binding unit 102 at the retracted position on the moving locus 335 of the crimping teeth 131 and 132 . are placed. The angle θa here is 22°, which is about half the swing angle θb (=45°) from the retracted position to the A4 binding position.

FIG. 15(b) shows the crimping teeth 131 and 132 and the cleaning member 331 of the binding unit 102 when the binding unit 102 has swung from the retracted position by an angle θa, viewed in the direction of arrow U shown in FIG. 15(a). It is a side view of time.

As shown in FIG. 15(b), a large number of brush bristles 312 are planted on the upper and lower surfaces of the tip of a plate-like cleaning member 331. As shown in FIG. The tip of the cleaning member 331 to which the brush bristles 312 are implanted enters the space 138 between the separated crimping teeth 131 and 132, and the tip of the brush bristles 312 is in contact with the crimping teeth 131 and 132. It has become. When the crimping teeth 131 and 132 come into contact with the brush bristles 312 of the cleaning member 331 while the binding unit 102 is swinging, the brush bristles 312 scrape off paper dust adhering to the crimping teeth 131 and 132 . As described above, if the crimping teeth of the pair of crimping teeth 131 and 132 to which paper dust is likely to adhere are known, the brush bristles 312 are applied only to the crimping teeth to which paper dust is likely to adhere. It is also possible to adopt a configuration in which paper dust is scraped off by contact.

In the above description, an example of cleaning the crimp teeth when the binding unit 102 swings from the retracted position to the A4 binding position has been described. Also, cleaning of the crimp teeth by the cleaning member 331 is performed during the swing.

If the cleaning member 331 is arranged fixedly, it is not necessary to drive the cleaning member 331 forward and backward with respect to the crimping teeth 131 and 132, so that the device configuration can be simplified.

(8-3) In the above embodiment, the binding unit 101 performs parallel binding with staples and the binding unit 102 performs oblique binding without staples, but the present invention is not limited to this. The binding unit 101 is moved in parallel along the sheet width direction to bind the sheet bundle Sb, and the binding unit 102 is swingable from one of the retracted position and the inclined binding position to the other, and the sheet is moved in the inclined position. Any configuration that obliquely binds the corner Su of the bundle Sb may be used. For example, the binding unit 101 may perform stapleless parallel binding, and the binding unit 102 may perform diagonal binding with a staple. Alternatively, for example, both of the binding units 101 and 102 may perform stapleless binding or staple binding.

(8-4) In the above embodiment, the configuration example in which the binding unit 102 swings between the retracted position and the inclined position about the swing shaft 129 of the main body 120 has been described, but the present invention is not limited to this. The binding unit 102 should not interfere with the binding unit 101 that has reached the corner binding position. A configuration in which a shaft is provided can also be adopted.

(8-5) In the above embodiment, the movement of the binding unit 101 from the home position to the corner binding position is started after the swinging of the binding unit 101 from the inclined position to the retracted position is completed ( Steps S16 to S19 in FIG. 12), but not limited to this. Before the binding unit 101 reaches the corner binding position, the binding unit 102 should be out of the area 101a (FIG. 13) occupied by the binding unit 101 after reaching the corner binding position.

When the time required for swinging the binding unit 102 from the inclined position to the retracted position is T1 seconds, and the time required for the binding unit 101 to reach the corner binding position from the home position is T2 (>T1) seconds, for example, It is also possible to control the binding unit 102 to start swinging from the inclined position to the retracted position when (T2-T1) seconds have elapsed since the binding unit 101 at the home position started to move.

(8-6) In the above embodiment, an example in which the image forming apparatus 1 is a multi-function machine has been described, but the present invention is not limited to this. As an image forming apparatus configured to discharge the sheet S to the sheet processing section 4 after forming an image on the conveyed sheet S, the image forming apparatus can be applied to, for example, a printer, a copying machine, a facsimile apparatus, and the like. Also, the sheet processing unit 4 can be regarded as a sheet processing apparatus that is optionally attached to the image forming apparatus. Furthermore, the sheets S to be bound are not limited to the sheets S after image formation. For example, after the user manually inserts the sheet bundle onto the tray 420 in the sheet conveying direction, it is also possible to use the operation unit 5 to manually instruct execution of the binding process.

In the above description, a configuration example in which the corner Su on the device back side of the sheet bundle Sb on the tray 420 is obliquely bound by the binding unit 102 has been described. By doing so, the corner St on the front side of the device can be obliquely bound. Furthermore, it goes without saying that the shape, size, material, etc. of each member such as the tray 420 and the binding units 101, 102 are not limited to those described above. is predetermined.

Also, the contents of the above embodiment and the above modifications may be combined as much as possible.

INDUSTRIAL APPLICABILITY The present invention can be widely applied to sheet processing apparatuses that bind a bundle of sheets.

1 image forming apparatus 3 printer section 4 sheet processing section 6 body control section 42 sheet alignment section 44 sheet processing control section 80 rack 89 long hole 91 base 92 guide member 101, 102 binding unit 129 swing shaft 120 main body 128 corner of binding unit Section 130 Head Section 131, 132 Crimping Teeth 151 Driving Section 152 Supporting Plate 209 Flat Gear 300 Cleaner 301, 331 Cleaning Member 302 Cleaning Driving Section 335 Trajectory of Movement of Crimping Teeth 420 Tray 441 First Control Section 442 Second Control Section S Sheet Sb Sheet bundle Su Corner of the sheet bundle on the back side of the device

Claims (9)

A sheet processing apparatus that stacks sheets conveyed onto a tray one by one and binds the stacked sheet bundle,
a first binding unit that obliquely binds one corner of a sheet bundle in an inclined posture inclined at a predetermined angle with respect to the sheet conveying direction;
a second binding unit capable of moving in the sheet width direction orthogonal to the conveying direction and selectively binding different portions including the corner portion of the sheet bundle;
When executing a job to bind the corner portion of the sheet bundle by moving the second binding unit, before the second binding unit reaches a predetermined position for binding the corner portion, the first binding unit is tilted, swinging means for swinging around a predetermined axis to a retracted position outside the area occupied by the second binding unit that has reached the predetermined position;
with
The first binding unit performs stapleless binding in which the corners of the sheet bundle are sandwiched between a pair of crimping teeth and bound by pressure without using a staple.
Further, the sheet processing apparatus includes a cleaner for cleaning at least one of the pair of crimping teeth of the first binding unit,
The cleaner
contacting at least one of the pair of crimping teeth during rocking of the first binding unit at a position in the middle of the movement trajectory of the pair of crimping teeth while the first binding unit is rocking; A sheet processing apparatus comprising a cleaning member for scraping off paper dust adhering to the crimp teeth. 2. The sheet processing apparatus according to claim 1, further comprising moving means for moving the first binding unit in the inclined posture in parallel along the sheet width direction while the first binding unit is in the inclined posture. The moving means
The first binding unit in the inclined posture is arranged at a first binding position for obliquely binding the corners of a sheet bundle of a first size and a second size having a shorter sheet width direction length than the first size. moving between a second binding position for obliquely binding the corner of the sheet bundle;
the second binding position is closer to the center of the tray in the sheet width direction than the first binding position in the sheet width direction;
The rocking means is
3. The sheet processing apparatus according to claim 2, wherein the first binding unit in the inclined posture at the first binding position among the first and second binding positions is swung to a retracted position. 4. The sheet processing apparatus according to claim 1 , wherein the second binding unit uses a staple to bind the sheet bundle. The first binding unit is arranged such that a main body and a head portion including a pair of binding members for sandwiching and binding a sheet bundle are aligned in a direction orthogonal to the predetermined axis, and the first binding unit is viewed from above. The sheet processing apparatus according to any one of claims 1 to 4 , wherein the sheet processing apparatus is elongated in a direction in which the main body and the head portion are aligned. 6. A sheet processing apparatus according to claim 5 , wherein said predetermined shaft is provided on said main body. 7. The sheet processing apparatus according to claim 6 , wherein the predetermined axis is parallel to a direction perpendicular to the sheet surface of the corner of the sheet bundle. 8. The sheet processing apparatus according to any one of claims 5 to 7 , wherein the retracted posture of the first binding unit at the retracted position is a posture in which the longitudinal direction thereof is parallel to the sheet conveying direction. An image forming apparatus for binding sheets on which images are formed by an image forming unit by a sheet processing unit,
An image forming apparatus comprising the sheet processing apparatus according to any one of claims 1 to 8 as the sheet processing section.

Images