JP5589484B2 - Post-processing apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a post-processing apparatus and an image forming apparatus.

  A post-processing apparatus may be connected to a subsequent stage of an image forming apparatus such as a printer that prints images or characters on paper. This post-processing device is equipped with a puncher that punches holes in the paper, a stapler that staples a stack of multiple sheets of paper with staples, and a paper folding machine that folds the paper, depending on the user's usage. Is done.

  Focusing on the stapler, a DC motor is mounted on the stapler, and a stapling operation is performed in which a staple is inserted into the sheet bundle and bent by a driving force generated by the rotation of the DC motor.

JP 2008-174382 A

  An object of the present invention is to improve the productivity of post-processing including a stapling operation.

The post-processing device according to claim 1 comprises:
A bundle forming unit that receives a recording medium from an image forming apparatus that forms an image on the recording medium, and forms a bundle by stacking a plurality of the recording media;
A stapler for performing a staple operation in which a staple is inserted and bent at a position along one side of the bundle;
A bundle moving unit for moving the bundle along the one side;
A stapler moving unit that moves the stapler along the one side simultaneously with the movement of the bundle;
The post-processing device includes a staple execution control unit that causes the stapler that is moving simultaneously with the bundle to execute the staple operation.

The image forming apparatus according to claim 2
An image forming unit that forms an image on a recording medium;
A bundle forming unit that receives a recording medium from the image forming unit and forms a bundle by stacking a plurality of the recording media;
A stapler for performing a staple operation in which a staple is inserted and bent at a position along one side of the bundle;
A bundle moving unit for moving the bundle along the one side;
A stapler moving unit that moves the stapler along the one side simultaneously with the movement of the bundle;
The image forming apparatus includes a staple execution control unit that causes the stapler that is moving simultaneously with the bundle to execute the staple operation.

  According to the post-processing apparatus of the first aspect, the productivity of the post-processing including the stapling operation is high as compared with the case where this configuration is not provided.

  According to the image forming apparatus of the second aspect, the productivity of the post-processing including the stapling operation is high as compared with the case where this configuration is not provided.

1 is an overall configuration diagram of a print system. It is operation | movement explanatory drawing of the mechanism around the stapler of the post-processing apparatus shown in FIG. It is a perspective view which shows the guide member in which two rails were formed. 1 is an overall configuration diagram of a printing system in which a copying machine and a post-processing apparatus are connected. It is the schematic diagram which showed the driving force transmission mechanism and sensor of a stapler. It is explanatory drawing of the operation mechanism of the pressing member with which the stapler was equipped. It is the figure which showed the positional relationship of a light-shielding plate and HP sensor. It is the figure which showed the shape of the staple. It is a top view which shows the state by which the needle plate was abutted by the needle stopper. FIG. 6 is a side view showing a state in which the staple needle is abutted against the needle stopper. It is a figure which shows operation | movement of the member in the 1st step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 2nd step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 3rd step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 4th step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 5th step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 5th step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 6th step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 7th step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 8th step of the staple operation by a stapler. It is a figure which shows operation | movement of the member in the 9th step of the staple operation by a stapler. It is the figure which showed the operation | movement sound waveform in each process which comprises a series of staple operations. It is a block diagram of the control circuit which bears the operation control of the stapler in the post-processing device. It is a control conceptual diagram. FIG. 6 is a diagram illustrating a group table that classifies a sheet bundle into groups according to the paper type and the number of sheets. It is a figure showing a duty table. 6 is a timing chart showing execution timings of a bundle creating operation, a stapling operation, and a shifting operation. FIG. 6 is a diagram illustrating positions of a stapler, a sheet bundle, and a hitting plate when a bundle creating operation and a stapling operation are executed. It is a figure which shows the initial state of a stapler in the staple operation of the 2nd time. FIG. 18 is a diagram illustrating a state corresponding to the state illustrated in FIG. 17 of the stapler in the second stapling operation. FIG. 6 is a diagram illustrating positions of a stapler, a sheet bundle, and a hitting plate when a shift operation and a sheet discharge operation are executed. 6 is a timing chart showing the start timing of a paper discharge operation. FIG. 6 is a diagram illustrating a state of a stapler at the start of a sheet discharge operation. FIG. 6 is a diagram illustrating a stapler and a sheet bundle at the end of a stapling operation. 6 is a timing chart for explaining another method for determining the start timing of a paper discharge operation. It is a figure which shows the time table for calculating | requiring "x" msec.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an overall configuration diagram of a printing system.

  The printing system 1A shown in FIG. 1 includes a printer 10, a paper transport device 20, and a post-processing device 30.

  The printer 10 is an electrophotographic printer that receives an image signal from a host device (not shown) and forms an image based on the image signal on a sheet. An outline will be described.

  The printer 10 is provided with four paper storage units 111. Each paper storage unit 111 stores paper PP having a different paper type, size, and orientation (portrait and landscape). . Information on the paper type, size, and orientation of the paper stored in each paper storage unit 111 is set in advance and stored in the main body control unit 120. When a print command is received from the host device, the paper PP is taken out by the take-out roll 112 from the paper storage unit 111 that stores the paper corresponding to the command, and the taken-out paper PP is supplied by the supply roll 113 and the transport roll 114. The leading edge of the paper is conveyed to the adjustment roll 115.

  On the other hand, the exposure device 121 exposes each photoconductor 122 arranged for each color of C, M, Y, and K, and forms an electrostatic latent image on each photoconductor 122. The electrostatic latent image formed on each photoconductor 122 is developed with each color toner by a developing device (not shown) to form a toner image, and each color toner image is stretched by a tension roll 124 by the action of the transfer roll 125. The toner images of the respective colors are transferred so as to overlap each other on the intermediate transfer belt 123 that circulates in the direction of the mark A in a suspended state.

  The paper PP having the leading end reaching the adjustment roll 115 is sent to the secondary transfer position T in accordance with the toner image on the intermediate transfer belt 123 and the time, and the secondary transfer roll 116 acts on the intermediate transfer belt 123. The toner image is transferred to the paper PP. The paper PP that has received the transfer of the toner image is further conveyed, heated and pressurized by the fixing roll 117, and the toner image on the paper is fixed to the paper PP, and a fixed image is formed on the paper PP. The fixed sheet PP is further conveyed by the conveyance roll 118, and is discharged onto the sheet discharge table 119 of the printer 10 when the sheet conveying apparatus 20 is not present.

  In this printing system 1A, since the paper transport device 20 is installed on the paper discharge table 119, the paper PP discharged from the printer 10 is inherited by the paper transport device 20, and the transport roll in the paper transport device 20 is used. 21 is further transported by the post-processing apparatus 30. The post-processing measure 30 will be described later.

  A command for each job is input to the printer 10 from the host device. Specifically, as an example, when the image signal for 10 sheets and the paper on which the image based on each image signal is formed are 1 to 10 pages, the paper of 1 to 10 pages is regarded as one sheet bundle, An instruction is issued such that ten sheets of paper bundles are created by binding with a staple needle for each paper bundle. For example, in the case of this example, the paper PP is sequentially taken out from the paper storage unit 111 that stores the paper according to the dimensions of the image, and the first page image and the second page are taken out to each paper PP taken out in order. ,..., The 10th page image, the 1st page image, the 2nd page image,..., The 10th page image are sequentially printed for a total of 10 bundles (100 sheets). . The printed paper is sequentially sent to the post-processing device 30 via the paper transport device 20.

  The post-processing device 30 includes a puncher 31 and a stapler 32, and a sheet processing control unit 35 that controls operation of the puncher 31 and communication with the printer 10. The paper taken into the post-processing device 30 is transported by the transport roll 131, and when it is instructed to form punch holes at the edges of the paper, the puncher 31 is activated, and the paper with punch holes is further formed. The paper is conveyed and discharged onto the paper tray 136. The paper tray 136 is movable up and down between a position indicated by a solid line and a position indicated by a broken line in FIG. 1, and descends in accordance with the total thickness of the sheets sequentially stacked on the paper tray 136.

  When the stapler 32 provided in the post-processing device 30 is instructed to bind the sheet bundle, the stapling operation by the stapler 32 is executed as follows.

  FIG. 2 is an operation explanatory view of a mechanism around the stapler of the post-processing device 30 shown in FIG.

  Here, a fixed plate 137 on which a sheet is placed and a movable plate 135 that can move forward and backward in the direction of arrow XX ′ are provided. In FIG. 2, the movable plate 135 has advanced in the direction of the arrow X. Further, here, a paper discharge roll 132 and a counter roll 133 are provided. The paper discharge roll 132 is movable up and down in the direction of arrow YY ′ shown in FIG. When the paper discharge roll 132 is lowered, the paper is sandwiched between the paper discharge roll 132 and the opposing roll 133, and is rotated to discharge the paper onto the paper tray 136 shown in FIG. Here, the paper discharge roll 132 is in a position raised in the arrow Y direction. Further, a paddle 134 and a hitting plate 139 are provided here. The paddle 134 rotates in the direction of arrow B and plays a role of pushing the paper toward the stapler 32 side. The sheet pushed toward the stapler 32 is abutted against the abutting wall 138. Further, one set of hitting plates 139 is arranged so as to sandwich the sheet from the left and right, and each hitting plate 139 is moved in the direction perpendicular to the paper surface of FIG. It is moved according to instructions from. The hitting plate 139 plays a role of aligning the horizontal position of the paper by hitting the paper in the horizontal direction (that is, the direction perpendicular to the paper surface of FIG. 2). The hitting plate 139 also has a role of moving the sheet bundle in the horizontal direction.

  The paper that has passed through the arrangement area of the puncher 31 shown in FIG. 1 proceeds along the paper conveyance path P1 shown in FIG. At this time, the paper discharge roll 132 is in a position raised in the arrow Y direction, and the movable plate 135 is in the state of being advanced in the arrow X direction. The paper that has traveled along the paper transport path P1 is placed across the fixed plate 137 and the movable plate 135, is abutted against the abutting wall 138 by the paddle 134, and is struck by the tapping plate 139, thereby positioning both vertically and horizontally. Is made. The above operation is repeated while the number of sheets forming one sheet bundle (10 sheets in the above example) is sent, so that a plurality of sheets forming one sheet bundle are vertically and horizontally positioned. Are stacked together. The plurality of stacked sheets are bound by a stapler 32 into one sheet bundle. A staple 33 having two protrusions 331 is attached to the stapler 32, and the two protrusions 331 of the legs 33 are provided on the guide member 34 and extend in a direction perpendicular to the paper surface of FIG. Each of the rails 342 enters a groove 341 formed in the rail 342. The stapler 32 is guided by the two rails 342 and is movable in a direction perpendicular to the paper surface of FIG. The foot 33 has a built-in motor, and the foot 33 moves the stapler 32 along the two rails 342 in accordance with an instruction from the paper processing control unit 35 shown in FIG. As a result, when the sheet bundle is bound by the stapler 32, the stapler 32 is guided by the rail 342 and moves, for example, at a designated position of the sheet bundle, such as two places near the center or one place in the corner.

  The stapling operation itself by the stapler 32 will be described later.

  In synchronism with the binding of the sheet bundle by the stapler 32, the sheet discharge roll 132 descends in the direction of the arrow Y ′ and the sheet bundle is sandwiched between the opposing roll 133, and the movable plate 135 moves in the direction of the arrow X ′. Retreat to. When the binding operation to the sheet bundle is completed, the sheet bundle is discharged onto the sheet receiving plate 136 by the rotation of the sheet discharge roll 132.

  While the above binding operation is being performed, adjustment between the printer 10 and the post-processing device 30 prevents the next sheet from being further conveyed from the printer 10 (see FIG. 1). The printing operation is interrupted. If the interruption time is long, the productivity of printing and sheet bundles will be reduced. For this reason, it is desired to increase the speed of the stapling operation, but if the speed of the stapling operation is increased, a loud operation sound is generated.

  Therefore, in the present embodiment, control for improving the productivity by shortening the interruption time and control for suppressing the generation of operation sound are performed. These control methods will be described later.

  FIG. 3 is a perspective view showing a guide member on which two rails are formed.

  Grooves 341 are respectively formed in the two rails 342 of the guide member 34, and the protrusion 331 of the foot 33 shown in FIG. 2 enters the groove 341 to guide the movement of the stapler 32. These rails 342 as a whole extend in a direction perpendicular to the paper surface of FIG. 2 but have curved shapes near both ends. This is because when corners of the sheet bundle are bound, corners of the sheet are bound obliquely with respect to the sheet.

  Here, the post-processing device 30 described with reference to FIGS. 1 to 3 can be connected not only to the printer having the form shown in FIG. 1 but also to another form of printer. Here, a copier including a configuration of another form of printer will be described.

  FIG. 4 is an overall configuration diagram of a printing system in which a copying machine and a post-processing apparatus are connected.

  The print system 1B is composed of a copying machine 40 and a post-processing device 30. The post-processing device 30 is the same as the post-processing device 30 shown in FIG. 1, and here, the same reference numerals as those shown in FIG.

  The copying machine 40 shown in FIG. 4 includes an image reading unit 41, an operation panel 42, and an image forming unit 43.

  The image reading unit 41 includes a transparent document table 411 that reads a document image, and a main body unit 412 that accommodates an optical scanning system including a lamp, a mirror, and the like (not shown). A document is placed on document platen 411 so that the document image is in contact with document platen 411. The document image is read by scanning with an optical scanning system, and an image signal representing the document image is generated. The generated image signal is stored in a memory in the main body control unit 450.

  The operation panel 42 accepts user operations. Here, various operations such as various settings, image reading and image formation start instructions are performed. Various instructions on the operation panel 42 are also stored in the main body control unit 450.

  The image forming unit 43 is an electrophotographic printer that forms an image on a sheet based on the image signal stored in the main body control unit 450.

  The image forming unit 43 is provided with three paper storage units 431. Each paper storage unit 431 stores paper PP having a different paper type, size, and orientation (vertical placement, horizontal placement). ing. Information on the paper type, dimensions, and orientation of the paper stored in the paper storage unit 431 is set in advance by operating the operation panel 42 and stored in the main body control unit 450. When a print command is received from the operation panel 42, the paper PP is taken out by the take-out roll 432 from the paper storage unit 431 in which the paper corresponding to the command is stored, and the taken-out paper PP is supplied to the supply roll 433 and the transport roll 434. Is conveyed along the sheet conveyance path R1, and the leading edge of the sheet reaches the adjustment roll 435.

  On the other hand, the exposure device 435 exposes each photoconductor 436 arranged for each color of C, M, Y, and K, and forms an electrostatic latent image on each photoconductor 436. The electrostatic latent image formed on each photoconductor 436 is developed with each color toner by a developing device (not shown) to form a toner image, and each color toner image is stretched by a tension roll 438 by the action of the transfer roll 437. The toner images of the respective colors are transferred so as to overlap each other on the intermediate transfer belt 439 that circulates in the direction of the arrow A in a suspended state.

  The paper PP having the leading end reaching the adjustment roll 435 is sent to the secondary transfer position T in accordance with the toner image on the intermediate transfer belt 439, and the secondary transfer roll 440 acts on the intermediate transfer belt 439. The toner image is transferred to the paper PP. The paper PP to which the toner image has been transferred is further transported by the transport belt 441, and the toner image on the paper is fixed to the paper PP by being heated and pressed by the fixing device 442 by the roll 442a and the belt 442b. A fixed image is formed on the PP. In the case of single-sided printing, the fixed sheet PP proceeds along the sheet conveyance path R2, the sheet correction unit 435 corrects the curve of the sheet, is further conveyed, and is discharged from the copying machine 40. The paper discharged from the copying machine 40 is passed on to the post-processing device 30 connected to the subsequent stage.

  When printing on both sides of the paper is designated, the paper after the image on the first side fixed by the fixing device 442 is conveyed along the paper conveyance path R3, and further reaches the paper conveyance path R4. Thereafter, the transport direction is reversed, and this time, the paper travels along the paper transport path R5 and further proceeds along the paper transport path R1. At this time, the paper is taken out of the paper storage unit 431 and is reversed from the front and back when the paper travels on the paper transport path R1. An image is formed on the second surface of the paper that has advanced to the paper conveyance paths R5 and R1 in the same manner as described above, and is discharged from the copier 40 through the paper conveyance path R2, and is then sent to the post-processing device 30. inherited.

  In this copying machine 40, designation is performed in units of one job by operating the operation panel 42. Specifically, as an example, an instruction is input to create 10 bundles of copy images in which 10 image images sequentially read by the image reading unit 41 are 1 to 10 pages. For example, in the case of this example, the paper PP is sequentially taken out from the paper storage unit 111 that stores the paper according to the dimensions of the image, and the first page image, the second page are taken out to each paper 3 taken out in order. , ..., 10th page image, 1st page image, 2nd page image, ..., 10th page image in total in the order of 10 bundles (100 sheets). It is done sequentially. However, one-sided printing is described here as an example. The printed sheets are sequentially sent to the post-processing device 30.

  The main body control unit 450 is responsible for storing image signals, storing commands by operating the operation panel 42, controlling the entire copying machine 40, and communicating with the post-processing device 30. The main body control unit 450 is also responsible for adjustments in operation with the post-processing device 30.

  The copier 40 can also receive an image signal in place of image reading by the image reading unit 41 and a command in place of operation of the operation panel 42 from the host device. In this case, an image is formed on the sheet in accordance with a command from the host device. The main body controller 450 is also responsible for communication with the host device.

  Here, the printer 10 shown in FIG. 1 and the copier 40 shown in FIG. 4 are shown as devices to which the post-processing device 30 is connected. However, the post-processing device 30 is not limited to the printer 10 or the copier 40, and The present invention is not limited to the electrophotographic method, and may be configured to be connectable to a printer of another print method such as an ink jet printer.

  Next, the operation of the stapler itself will be described.

  FIG. 5 is a schematic diagram illustrating a driving force transmission mechanism and a sensor of the stapler.

  The stapler 32 has a pressing member 328. The stapler 32 is provided with a DC motor 321. When the DC motor 321 rotates, the presser member 328 rotates in the direction of arrow DD ′.

  The driving force transmission mechanism from the DC motor 321 to the presser member 328 is as follows. When the DC motor 321 rotates, the driving force is transmitted in the order of the gear 322, the relay gear 323, and the driving gear 324, and the driving shaft 325 rotates. After the description of FIGS. 6 and 7, the description will return to FIG. 5 again.

  FIG. 6 is an explanatory diagram of an operation mechanism of a pressing member provided in the stapler.

  The presser member 328 moves up and down between an upper position shown in FIG. 6A and a lower position shown in FIG. 6B by rotating around the rotation center 328a. Here, a drive cam 326 is attached to the drive shaft 325, and the presser member 328 moves up and down via a relay cam 327 that rotates about a rotation center 327a. When the drive shaft 325 rotates once, the presser member reciprocates once, and one stapling operation ends.

  Further, the light shielding plate 51 is attached to the drive shaft 325 at a position different from the drive cam 326 in the axial direction (direction perpendicular to the paper surface of FIG. 6). The light shielding plate 51 is fixed to the drive shaft 325 and rotates by the same rotation angle at the same speed in synchronization with the rotation of the drive cam 326. An HP (home position) sensor 52 is provided in the vicinity of the light shielding plate 51.

  FIG. 7 is a diagram showing the positional relationship between the light shielding plate and the HP sensor.

  The HP sensor 52 is a photoelectric sensor that projects and receives light, and is fixed at a position where the rotating light-shielding plate 51 passes so as to block light projection and reception by the HP sensor 52. The HP sensor 52 outputs an L level signal while the light shielding plate 51 is passing, and outputs an H level signal when the light shielding plate 51 is separated from the HP sensor 52. Since the light shielding plate 51 rotates together with the rotation of the drive shaft 325, the rotation position of the drive shaft 325 is detected by the HP sensor 52. Here, this sensor is used for detection of the initial position of the drive shaft 325 and detection of a specific operation point described later during the stapling operation.

  After the electric power is supplied to the DC motor 321 and the stapler 32 starts the stapling operation, the HP sensor 52 indicates that the drive shaft 325 rotates once and returns to the initial position even after a certain threshold time (for example, 500 msec) elapses. If it is not detected in step (3), it is considered that the stapling operation is defective, the rotation of the DC motor 321 is stopped, and the DC motor 321 is reversed. When the DC motor 321 is reversed, the HP sensor 52 monitors whether the drive shaft 325 returns to the initial position within a certain threshold time (for example, 200 msec). Although the processing contents differ depending on whether or not the HP sensor 52 detects that the drive shaft 325 has returned to the initial position within the threshold time due to the reverse rotation of the DC motor 321, error processing is performed in either case.

  Returning to FIG. 5, various sensors provided in the stapler 32 will be described.

  The stapler 32 is provided with a sensor 53 and a sensor 54 in addition to the HP sensor 52. The sensor 53 is a sensor that detects whether or not a staple needle (described later) is in a state in which a staple operation for binding a sheet bundle can be performed. The sensor 54 is a sensor that detects that the remaining number of staples has decreased.

  FIG. 8 is a diagram showing the shape of the staple needle.

  The staple needle 61 has a linear shape, and as shown in FIG. 8A, the linear staple needles 61 are arranged in a single plate shape and bonded so that they do not easily fall apart. 60 is formed. Here, as for the staple needle 61 in use, only the leading two staple needles 61 a and 61 b are bent in a direction in which both end portions thereof are erected at right angles from the needle plate 60.

  As shown in FIG. 8B, the left and right tip portions of the staple needle 61 are formed in a tapered shape so that the thickness becomes thinner toward the tip, facilitating insertion into the sheet bundle.

  FIG. 9 is a plan view showing a state in which the needle plate is abutted against the needle stopper. The staple stopper 62 has a first stopper 62a against which both ends of the linear staple needle 61 before being bent are abutted, and a leading staple needle 61a among the two staple needles 61a and 61b which are bent. And a second stopper 62b to be applied. A guide member 63 is placed on the needle plate 60. The leading end portion of the guide member 63 has a size that enters the inside of the two staple needles 61a and 61b that are bent.

  FIG. 10 is a side view showing a state in which the staple needle is abutted against the needle stopper.

  The guide member 63 is formed with an inclined surface 63a so as to cover the upper part of the bent staple needle 61a and expose the lower part. The guide member 63 is urged in the direction of arrow E shown in FIG.

  The stapler 32 further includes a needle push-up member 71 having a thickness substantially the same as the width of one staple needle 61 and a needle bending member 72 having a similar thickness. The needle push-up member 71 is disposed immediately below the folded leading staple needle 61a, and the needle bending member 72 is disposed directly below the third staple needle 61 from the leading end, that is, directly below the leading staple needle that has not yet been folded. Has been.

  When the DC motor 321 (see FIG. 5) provided in the stapler 32 rotates and the drive shaft 325 rotates, the needle push-up member 71 pushes up the staple needle 61a at the tip in the arrow G direction and inserts it into a sheet bundle (not shown). At the time of this push-up, the guide member 63 is pushed back by the thickness of one staple needle 61 in the direction of arrow F shown in FIG. 10B against the spring bias. Then, by the needle bending member 72 that has been raised following the staple pushed up by the needle push-up member 71, the leading staple needle that has not been bent is bent with the leading end portion of the guide member 63 as a guide. The needle push-up member 71 and the needle bending member 72 are lowered to the initial position shown in FIG. 10A when the binding operation for one bundle of sheets by the staple needle 61a pushed up by the needle push-up member 71 is completed.

  FIG. 11 to FIG. 20 are diagrams illustrating the operation of the member in each step of the staple operation by the stapler. As described above, the stapler 32 is provided with the DC motor 321 (see FIG. 5), and the drive shaft 325 is rotated by the rotation of the DC motor 321. The rotation of the drive shaft 325 causes each of the operations related to the stapling operation. The members operate in coordination.

  FIG. 11 shows an initial state immediately after the needle plate 60 is loaded on the stapler. A plurality of needle plates 60 are accommodated in a stacked manner. Here, in addition to the needle stopper 62, the needle push-up member 71, the needle bending member 72, which are composed of the first stopper 62a and the second stopper 62b described with reference to FIGS. 73 is shown. The leaf spring 73 plays a role of feeding the lowermost needle plate 60a of the stacked needle plates 60 to the needle stopper 62 side. Also shown here are a needle bending member 74, a presser member 75, and an upper member 76, which are components constituting the presser member 328 shown in FIG. The needle folding member 74 plays a role of bending both ends of the staple needle penetrating the paper bundle and pressing them against the paper bundle, and the presser member 75 plays a role of pressing the needle folding member 74 from above. ing. The upper member 76 plays a role of pressing the sheet bundle from above.

  FIG. 12 shows the next step in the state shown in FIG.

  Here, the lowermost needle plate 60a is pushed and moved in the direction of arrow H by the leaf spring 73, both ends of the tip of the needle plate 60a are abutted against the first stopper 62a, and the upper member 76 is further bent. The member 74 and the presser member 75 are moved downward in the direction of arrow I while remaining on the top. The upper member 76 is formed with a groove 761 into which the needle bending member 74 is inserted. The lower part of the upper member 76 causes the needle bending member 74 to move relative to the upper member 76 so that the groove 761 is formed. It appears.

  Next, as shown in FIG. 13, the needle push-up member 71 rises in the direction of arrow J. At this stage, there is no staple needle 61a (see FIG. 9) abutted against the second stopper 62b. Therefore, the needle push-up member 71 is idle. As the needle push-up member 71 is raised, the needle bending member 72 is also raised, and both ends of the leading staple needle 61 abutted against the first stopper 62a are bent at right angles to the needle plate 60a. At this time, the leaf spring 73 continues to urge the needle plate 60a in the arrow H direction.

  Next, as shown in FIG. 14, the presser member 75 is lowered in the direction of the arrow K, and the needle folding member 74 is pushed into the groove 761. At this stage, there is no staple needle, and the punching is performed. The leaf spring 73 once moves backward.

  Next, as shown in FIG. 15, the upper member 76 rises in the arrow L direction together with the needle bending member 74 and the pressing member 75, and the needle pushing up member 71 and the needle bending member 72 are lowered in the arrow M direction. The staple plate 61a is pushed by the leaf spring 73 and the first staple needle 61a that is bent rubs through the first stopper 62a, and the second staple needle 61b that is not yet bent from the first is the first staple needle 61b. The state is abutted against the stopper 62a.

  Next, when the steps of FIGS. 13 to 15 are repeated again, the leading two staple needles 61a and 61b are bent this time, and the leading staple needle 61a becomes the second stopper 62b as shown in FIG. It will be in a state of being hit.

  The sensor 53 shown in FIG. 5 is a sensor that detects that the leading staple needle 61a of the needle plate 60a bent as described above is in contact with the second stopper 62b. When this state is detected by the sensor 53, the actual stapling operation for binding the sheet bundle can be executed.

  Here, the idle driving operation shown in FIGS. 13 to 15 is repeated up to 13 times. This is because the feeding of the needle plate 60a by the leaf spring 73 may fail. If the sensor 53 does not detect the presence of the leading staple 61a even after repeating the steps of FIGS. 13 to 13 13 times, error processing is executed.

  FIG. 16 shows a state at the start of actual stapling operation.

  Here, the leading two staple needles 61a and 61b of the needle plate 60a are bent, and the leading staple needle 61a is abutted against the second stopper 62b. FIG. 16 also shows a sheet bundle PS scheduled to be stapled.

  Next, as shown in FIG. 17, the leaf spring 73 pushes the needle plate 60a in the arrow N direction to push the needle plate 60a against the needle stopper 62, and the upper member 76 descends in the arrow O direction to raise the sheet bundle PS. It can be pressed from. At this time, a groove 761 is formed.

  Next, as shown in FIG. 18, the needle push-up member 71 rises in the direction of the arrow P, and the sheet bundle PS is penetrated by the leading staple needle 61a. The needle bending member 72 is also raised, and the both side portions of the two adjacent straight leading staple needles 61 are bent upward.

  Next, as shown in FIG. 19, the presser member 75 is lowered in the direction of the arrow Q, the needle bending member 74 is pushed into the groove 761, and both ends of the staple needle 61a are bent inward. The groove 761 is formed slightly obliquely so that both ends of the staple needle 61a bent inward do not collide with each other.

  Next, as shown in FIG. 20, the upper member 76 rises in the direction of arrow R, and accordingly, the needle folding member 74 and the presser member 75 also rise together with the upper member 76. In addition, the needle push-up member 71 and the needle bending member 72 are lowered in the arrow S direction. The needle plate 60a is pushed by the leaf spring 73, and the next leading staple is abutted against the second stopper 62b.

  The sheet bundle PS bound by the staple needle is discharged to the outside of the post-processing device 30 as described with reference to FIG.

  The above steps of FIGS. 16 to 20 are repeated, and the sheet bundle PS bound by the staple needle 61 is sequentially formed.

  Another sensor 54 shown in FIG. 5 is a sensor that detects that the number of remaining staples 61 has decreased as a result of consuming the staples 61 as described above. When the remaining staple needles 61 are low, a warning is given to the user.

  FIG. 21 is a diagram showing an operation sound waveform in each process constituting a series of stapling operations. FIG. 21 also shows the light shielding plate 51 and the HP sensor 52. In this figure, the rotation direction of the light shielding plate 51 is counterclockwise.

  Here, a series of stapling operations are divided into a starting step T1, a binding step T2, and a return step T3. In the present embodiment, the time length t1 of the starting process T1 is fixed at t1 = 50 msec. Further, the timing for releasing the sheet press after the binding step T2 can be known from the change in the output of the HP sensor 52. Further, the end timing (that is, the initial state) of the return process T3 can be known from the output change of the HP sensor 52.

  The starting process T1 is a time of 50 msec from the time when the power supply to the DC motor 321 (see FIG. 5) is started in the initial state shown in FIG. The binding process T2 is a process that continues to the state of FIG. 19 following the start process T1. The return step T3 is a step for performing the operation described with reference to FIG.

  Here, the time length of the starting step T1 is t1, the time length of the binding step T2 is t2, the time length of the returning step T3 is t3, and a series of one stapling operation from the start of the starting step T1 to the end of the returning step T3. Is expressed as t123. The total time length t1 + t2 of the starting process T1 and the binding process T2 is represented by t12.

  Below, the control algorithm for reducing the operation sound in the binding process T2 and the return process T3 will be described.

  FIG. 22 is a block diagram of a control circuit responsible for operation control of the stapler in the post-processing apparatus.

  Here, it is assumed that the post-processing device 30 is connected to the printer 10 shown in FIG.

  Here, a CPU 351, a RAM 352, a motor driving unit 353, and an oscillator 354 are shown. These are some of the components in the sheet processing control unit 35 shown in FIG.

  Also shown here are the DC motor 321, the stapling mechanism 39 including the various mechanical elements described above, and the HP sensor 52 as components of the stapler 32.

  Various kinds of data to be described later stored in a non-volatile memory (not shown) are transferred to the RAM 352 when the power of the post-processing device 30 is turned on, and an operation control program operating on the CPU 351 is also loaded into the RAM 352. The CPU 351 receives information such as the type of paper (paper type) used for the current print, the number of sheets per bundle, the number of sheets bundle, and the like from the printer 10. The CPU 351 also receives the output signal of the HP sensor 52, and the CPU 351 recognizes that the stapler 32 is in the initial state and that the paper presser is at the release timing.

  In the motor drive unit 353, the pulse width modulation power with the duty instructed by the CPU 351 is generated. The oscillator 354 generates a clock signal for generating pulse width modulation power (PWM power) in the motor driving unit 353.

  Here, PWM is a technique for modulating power into a periodic pulse-like waveform. The pulse height in the modulated waveform is equal to the rated voltage of the DC motor 321. The ratio of the pulse width to the pulse period in the modulated waveform is the ratio of the effective output to the rated output. This ratio is referred to as PWM power duty (output ratio). By adjusting this duty, the effective output of PWM power is adjusted between 0 and the rated power.

  The PWM power generated by the motor drive unit 353 is supplied to the DC motor 321, and the DC motor 321 rotates with the supplied PWM power. Here, the DC motor 321 rotates at a rotational speed approximately in accordance with the duty of the PWM power supplied to the DC motor 321, but depending on the individual difference of the stapler 32, the paper type and number of sheets to be bound, and the like. It varies greatly, and the duty and the rotational speed are not necessarily in a one-to-one relationship.

  FIG. 23 is a conceptual diagram of control.

  The control to be performed here is to adjust the duty for each process. The starting step T1 is a step of starting the rotation of the DC motor 321 and requires a large amount of power, and is fixed at a duty of 100% here. The time length t1 of the starting process T1 is fixed at t1 = 50 msec as described above.

  In the next binding step T2, the duty is adjusted to a duty according to the paper type, the number of sheets, and the like of the binding target paper, and operation noise is suppressed. When the duty is lowered, the rotational speed of the DC motor 321 is reduced. However, not only the rotational speed is reduced but also the driving force is reduced. Therefore, the duty of the binding step T2 is determined to be a minimum duty that ensures a driving force that does not cause a binding failure.

  Also in the next return step T3, the duty is adjusted to a duty according to the paper type, the number of sheets, and the like of the binding target paper. Even in this return step T3, if the driving force is excessively reduced, the return operation may be defective. Therefore, the duty of the return process T3 is determined to be a minimum duty that ensures a driving force that does not cause a failure of the return operation.

  When the duty is changed as shown by a solid line in FIG. 23, the actual rotational speed of the DC motor 321 follows the change of the duty with a time delay or the like as shown by a broken line here.

  FIG. 24 is a diagram showing a group table for classifying a sheet bundle into groups according to the paper type and the number of sheets.

  In the group table shown here, the number of sheets to be stapled (the number of staples) is divided into five sections by dividing 10 sheets. Further, as the types of paper, six types of paper, “thin paper”, “plain paper 1”, “plain paper 2”, “thick paper”, “coated paper”, and “thick paper 2” are assumed in order from the thinnest. Yes. This group table indicates which group of what type of paper is to be bundled when it is bundled.

  As shown in FIG. 22, information on the paper type used for the current print, the number of sheets per bundle and the number of bundles is input from the printer 10 to the post-processing device 30. A group of sheet bundles is determined by referring to the group table using information on the paper type and the number of sheets per bundle.

  In the group table shown here, the sheet bundle to be bound is divided into three groups of A group, B group, and C group according to the paper type and the number of sheets. The load required for the stapling operation on the sheet bundle is a low load in the A group, a medium load in the B group, and a high load in the C group. For example, for plain paper 1 having a thin paper thickness, a bundle of 2 to 10 sheets belongs to the A group, and a bundle of 11 to 30 sheets belongs to the B group. If the number is 31 or more, it belongs to the C group. On the other hand, even two coated papers having a thick paper thickness belong to the C group.

  The information shown in FIG. 24 is stored in a nonvolatile memory (not shown), and is loaded into the RAM 352 shown in FIG. 22 prior to the operation.

  FIG. 25 is a diagram illustrating a duty table.

  In the duty table shown here, the duty in each of the start process T1, the binding process T2, and the return process T3 is associated with each of the three groups of the A group, the B group, and the C group. D1, d2, and d3 shown in FIG. 25 represent the duty of the starting process T1, the binding process T2, and the return process T3, respectively.

  Regarding the starting process T1, the duty is fixed to 100% for all three groups of the A group, the B group, and the C group.

  The duty of each of the binding process T2 and the return process T3 is a duty corresponding to the group to which the sheet bundle belongs. Looking at the binding process T2, a duty of 65% is associated with the A group, a duty of 75% is associated with the B group, and a duty of 85% is associated with the C group. Looking at the return step T3, the A group is associated with a duty of 50%, the B group is associated with a duty of 40%, and the C group is associated with a duty of 25%. . As described above, in the duty table, a larger duty is associated with a group having a larger load required for the stapling operation. As a result, a balance between avoidance of staple failure due to insufficient driving force and reduction in staple operation sound is maintained.

  The information shown in FIG. 25 is also stored in a nonvolatile memory (not shown), and is loaded into the RAM 352 shown in FIG. 22 prior to the operation.

  Hereinafter, the operation timing of each operation executed before and after the stapling operation will be described. Before the stapling operation, a bundle creating operation for creating a sheet bundle to be stapled is executed. As described above with reference to FIGS. 1 and 2, the bundle creating operation is an operation performed by the paddle 134 and the hitting plate 139. Further, after the stapling operation, a paper discharge operation is performed in which the paper discharge roll 132 and the opposing roll 133 discharge the bound paper bundle onto the paper receiving tray 136. Further, a shift operation for alternately shifting the sheet bundle so that the staple portions do not overlap between the sheet bundles on the sheet receiving tray 136 is also executed prior to the sheet discharge operation. This shift operation is performed by the hitting plate 139. The timing of any operation is controlled by an instruction from the sheet processing control unit 35 of the post-processing device 30 to each drive unit. This instruction is specifically realized by transmission of an instruction signal or the like. However, since the instruction technique itself is a well-known technique, further explanation is omitted, and the operation timing realized by the instruction will be described below. .

  FIG. 26 is a timing chart showing execution timings of the bundle creating operation, stapling operation, and shift operation. FIG. 27 is a diagram illustrating the positions of the stapler, the sheet bundle, and the hitting plate when the bundle creating operation and the stapling operation are executed.

  In the timing chart of FIG. 26, the timing of the position change of each of the pair of hitting plates 139, the execution timing of the stapling operation, and the timing of the position change of the stapler 32 are indicated by four lines. Is a common time axis. Further, in this timing chart, an example in which two places are bound for one sheet bundle PS is shown.

  The two lines on the upper side of the timing chart indicate the positional change of each of the pair of hitting plates 139, and the vertical direction in FIG. 26 corresponds to the vertical direction in FIG. As shown in the timing chart of FIG. 26, the pair of hitting plates 139 moves so as to sandwich the sheet bundle PS. Such sandwiching is performed each time a new sheet is added to the sheet bundle PS. When the number of sheets reaches the number of sheets per bundle input from the printer 10, the stapler 32 moves to the first binding position as indicated by the bottom line of the timing chart. The first binding position is indicated by a dotted line in FIG.

  Then, with the pair of hitting plates 139 sandwiching the paper, the first stapling operation is executed as indicated by the second line from the bottom in FIG.

  When the first stapling operation is completed, the stapler 32 moves to the second binding position as indicated by the lowermost line of the timing chart of FIG. 26 and the arrow U of FIG. When the stapler 32 reaches the second binding position, the second stapling operation is started as indicated by the second line from the bottom of FIG.

  FIG. 28 is a diagram showing an initial state of the stapler in the second stapling operation, and this initial state corresponds to the initial state shown in FIG.

  In the initial state of the stapler, the sheet bundle PS to be bound by the staple needle is set with respect to the stapler 32, and the pressing member 328 is positioned in the upper part of the drawing.

  FIG. 29 is a diagram illustrating a state corresponding to the state illustrated in FIG. 17 of the stapler in the second stapling operation.

  When the motor of the stapler 32 is started from the state shown in FIG. 28, the pressing member 328 is lowered downward in the figure by the driving force of the motor, and the sheet bundle PS is pressed by the pressing member 328. After reaching the state shown in FIG. 29, as shown in the timing chart of FIG. 26, the stapler 32 and the pair of hitting plates 139 move together. As a result, a shift operation is executed.

  FIG. 30 is a diagram illustrating positions of the stapler, the sheet bundle, and the hitting plate when the shift operation and the sheet discharge operation are executed.

  As indicated by an arrow V in FIG. 30, the stapler 32 and the pair of hitting plates 139 move upward in the drawing, and the sheet bundle PS also moves upward in the drawing as the one hitting plate 139 moves. . The operation of moving the sheet bundle PS in this way is a shift operation. During this movement, as shown in FIG. 29, the presser member 328 holds the sheet bundle PS, and during this movement (ie, during the shift operation), the stapler is in the state shown in FIG. 18 and FIG. Then, the stapling operation is advanced. That is, the shift operation and the stapling operation are proceeding simultaneously, and as a result, the total time for executing the operation is shortened.

  Thereafter, as indicated by an arrow W in FIG. 30, a paper discharge operation is started. The start timing of this paper discharge operation will be described with reference to a timing chart that is more detailed than the timing chart of FIG.

  FIG. 31 is a timing chart showing the start timing of the paper discharge operation.

  In the timing chart of FIG. 31, the execution timing of the stapling operation, the output of the HP sensor 52, and the execution timing of the paper discharge operation are indicated by three lines, and the horizontal axis is a common time axis. Yes.

  As indicated by the middle line of this timing chart, the output of the HP sensor 52 temporarily changes from off to on upon execution of the stapling operation. Since the light shielding plate 51 has the shape shown in FIG. 21, the output change from off to on occurs at the timing when the pressing member 328 releases the pressing of the sheet bundle PS after the binding step T2. Then, the sheet processing control unit 35 captures this output change, and starts the sheet discharge operation as indicated by the lower line of the timing chart. The timing at which the sheet bundle PS is released is substantially dependent on the duty determined by the duty table shown in FIG. 25, but varies depending on individual differences of the stapler 32, the paper type and number of sheets to be bound, and the like. However, since the output change of the HP sensor 52 always occurs in synchronization with the stapling operation, the start timing of the sheet discharge operation is set to the release timing of the sheet bundle PS by the control based on the output change of the HP sensor 52. Always sync.

  FIG. 32 is a diagram illustrating a state of the stapler at the start of the sheet discharge operation.

  The sheet bundle PS is pulled out from the stapler 32 as indicated by an arrow W in the drawing by the sheet discharging operation. At this time, in the stapler 32, the return operation of the stapling operation is being executed, and the pressing member 328 has just started to release the pressing of the sheet bundle PS.

  FIG. 33 is a diagram illustrating the stapler and the sheet bundle at the end of the stapling operation.

  At the end of the stapling operation, the presser member 328 is fully raised and returns to the initial state. At this time, the sheet bundle PS has already been sent in the direction of the arrow W. Thus, even when the paper discharge operation and the stapling operation return process are proceeding simultaneously, the total operation execution time is shortened.

  In the above description, the method for determining the start timing of the sheet discharge operation when the stapler having the HP sensor 52 that generates an output change at the timing when the pressing of the sheet bundle PS is released has been described. However, when a stapler that does not have an HP sensor that causes such an output change is used, another determination method is required. Hereinafter, such another determination method will be described.

  FIG. 34 is a timing chart for explaining another method for determining the start timing of the paper discharge operation.

  In the timing chart of FIG. 34, as in the timing chart of FIG. 31, the execution timing of the stapling operation, the output of the HP sensor, and the execution timing of the paper discharge operation are indicated by three lines. Is a common time axis.

  The output of the HP sensor shown in the middle part of the timing chart of FIG. 34 causes an output change representing the initial state of the stapler, but does not cause an output change at the release timing of the sheet bundle PS. Therefore, in another method for determining the start timing, the time when “x” msec has elapsed after the start of the stapling operation is used as the start timing of the sheet discharge operation. This “x” msec is the estimated time from the start of the stapling operation to the release of paper press. However, as described above, the timing at which the sheet bundle PS is released is substantially dependent on the duty determined by the duty table shown in FIG. 25, and therefore the value of “x” will be described below. The value depends on the group to which the sheet bundle belongs.

  FIG. 35 is a diagram showing a time table for obtaining “x” msec.

  In this time table, the group from which the duty is determined is associated with the estimated time from the start of the stapling operation to the release of sheet press. A long time of 350 msec is associated with the A group that is the origin of the low duty, 310 msec is associated with the B group, and a short time of 280 msec is associated with the C group. Each time correlated in this way is a time calculated in advance by an experiment or the like. By referring to such a time table based on the group determined by the group table shown in FIG. 24, “x” msec for obtaining the start timing of the sheet discharge operation is determined. Even when the paper discharge operation is started at the start timing determined in the above-described “x” msec, the staple operation return process and the paper discharge operation sufficiently overlap each other, and the total operation execution time is as follows. It will be shortened.

  In the above-described embodiment, the duty is controlled in order to reduce the operation noise. However, in the present invention, the duty control is not essential, and the stapler motor may be always driven with a rated DC voltage. Good.

DESCRIPTION OF SYMBOLS 1A, 1B Print system 10 Printer 20 Paper conveyance apparatus 30 Post-processing apparatus 31 Puncher 32 Stapler 33 Foot part 34 Guide member 35 Paper processing control part 39 Staple mechanism 40 Copying machine 41 Image reading part 42 Operation panel 43 Image formation part 51 Light-shielding plate 52 HP (Home Position) Sensor 53, 53a, 54 Sensor 60, 60a Needle Plate 61, 61a, 61b Staple Needle 62, 62a, 62b Needle Stopper 63 Guide Member 71 Needle Push-Up Member 72 Needle Bending Member 73 Plate Spring 74 Needle Bending Member 75 Pressing member 76 Upper member 111 Paper storage portion 112,432 Take-out roll 113,433 Supply roll 114,118,121,131,434 Transport roll 115,435 Adjustment roll 116,440 Secondary transfer roll 117 Fixing Roll 119 Paper discharge table 120,450 Main body control unit 134 Padra 135 Movable plate 136 Paper receiving plate 137 Fixed plate 138 Abutting wall 139 Horizontal support plate 321 DC motor 322 Gear 323 Relay gear 324 Drive gear 325 Drive shaft 326 Drive cam 327 Relay Cam 327a, 328a Center of rotation 328 Presser member 331 Protrusion 341, 761 Groove 342 Rail 351 CPU
352 RAM
353 Motor drive unit 354 Oscillator PP Paper PS Paper bundle R1, R2, R3, R4, R5 Paper transport path

Claims (2)

A bundle forming unit that forms a bundle by stacking a plurality of recording media sequentially conveyed in the conveying direction;
A stapler that performs a staple operation of inserting and bending a staple in a portion along one side of the bundle that extends in the width direction intersecting the transport direction; and
A bundle moving unit that moves the bundle in the width direction along the one side;
A stapler moving unit that moves the stapler along the one side in the width direction simultaneously with the movement of the bundle and in the same direction as the movement direction of the bundle;
A post-processing apparatus, comprising: a staple execution control unit that causes the stapler that is moving simultaneously with the bundle and in the same direction as the bundle to move, to execute the staple operation. An image forming unit that forms an image on a recording medium;
A bundle forming unit that forms a bundle by stacking a plurality of the recording media on which an image is formed in the image forming unit and further sequentially transported in the transport direction;
A stapler that performs a staple operation of inserting and bending a staple in a portion along one side of the bundle that extends in the width direction intersecting the transport direction; and
A bundle moving unit that moves the bundle in the width direction along the one side;
A stapler moving unit that moves the stapler along the one side in the width direction simultaneously with the movement of the bundle and in the same direction as the movement direction of the bundle;
An image forming apparatus comprising: a staple execution control unit that causes the stapler that is moving simultaneously with the bundle and in the same direction as the movement of the bundle to execute the staple operation.

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