JP5897497B2 - Paper post-processing device - Google Patents

Description

  The embodiment described in this specification relates to a technique for performing post-processing of paper discharged from an image forming apparatus such as a copying machine, a printer, or a multifunction peripheral.

  A sheet post-processing device disposed on the sheet discharge side of the image forming apparatus is disposed below the intermediate tray (buffering mechanism) for temporarily stacking a plurality of sheets discharged from the image forming apparatus, It has a processing tray to which a plurality of sheets stacked on an intermediate tray are supplied in a drop manner, and a paper discharge tray from which the sheets stacked on the processing tray are discharged (Patent Document 1).

  The intermediate tray has a pair of intermediate tray members that move along a lateral direction orthogonal to the transport direction (vertical direction), and moves a plurality of sheets temporarily stacked on the processing tray by moving away from each other. Drop it. At that time, the rear end of the paper in the vertical direction is knocked down on the processing tray by the rotation of the drop assisting member that holds the rear end of the paper in the vertical direction. In addition, when stacking a plurality of sheets sequentially on the intermediate tray, the rear end in the vertical direction of the already stacked sheets is gripped by the rear end pressing unit, and is the leading end in the conveyance direction of the next supplied sheet The longitudinal tip is prevented from being pushed out by frictional contact with the loaded paper, and the leading edges of the paper are aligned.

  It is desirable that the sheet post-processing apparatus discharges the sheet at the same processing speed following the processing speed (number of printed sheets per unit time) of the image forming apparatus. For this reason, as the processing speed increases, it is necessary to increase the processing speed of the sheet post-processing apparatus. At that time, it is also necessary to align the end surfaces of the discharged sheets.

JP 2007-191244 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a paper post-processing apparatus that can increase the processing speed and can discharge paper with the front ends of the paper aligned.

The sheet post-processing apparatus according to the present embodiment includes a buffer unit that waits for a sheet fed from the image forming apparatus, and a processing tray that is disposed below the buffer unit and to which the sheet is supplied from the buffer unit. A processing tray unit that enables conveyance of sheets supplied and stacked from the buffer unit to the processing tray in a discharge direction; a post-processing unit that performs post-processing on the sheets stacked on the processing tray; and the processing tray A paper discharge tray portion having a paper discharge tray for discharging a bundle of post-processed paper stacked on the paper, a first chuck portion for holding a rear end of the paper waiting in the buffer portion, and a paper tray placed on the processing tray a second chuck part and a second chuck driving unit for driving the second chuck body portion for holding the trailing edge of the sheet and the second chuck body portion, the rear end of the sheet to be placed on the discharge tray Having a third chuck for lifting.

The buffer unit feeds the next sheet onto the sheet held by the first chuck unit, and the processing tray unit is configured to transfer the buffer unit onto the sheet held by the second chuck unit. And the paper discharge tray unit discharges the paper from the processing tray unit onto the paper on the paper discharge tray held by the third chuck unit, and drives the second chuck. The unit is configured to move between a pressing position for holding the sheet by pressing and contacting the upper surface of the uppermost sheet stacked on the processing tray and a retreating position for retracting upward from the pressing position. 2 that drive the chuck body portion.

1 is a schematic front view illustrating an embodiment of a sheet post-processing apparatus. The perspective view of the buffer part shown in FIG. The perspective view of the processing tray shown in FIG. FIG. 2 is a schematic diagram of a first chuck portion shown in FIG. 1. Schematic of the paddle part shown in FIG.

  Hereinafter, a sheet post-processing apparatus according to an embodiment will be described with reference to the drawings.

  1 is a schematic view showing an embodiment of a paper post-processing apparatus, FIG. 2 is a perspective view showing a paper buffer section in FIG. 1, and FIG. 3 is a perspective view showing a processing tray in FIG.

  The sheet post-processing apparatus 1 according to the present embodiment includes a sheet buffer unit 3, a processing tray unit 5, a stapler unit 7 as a post-processing unit that performs post-combination processing, and a paper discharge tray unit 9. Adjacent to the side. A processing tray 51 of the processing tray unit 5 is disposed below the paper buffer unit 3, and a paper discharge tray unit 9 and a stapler unit 7 are disposed before and after the processing tray 51 in the paper transport direction. Note that post-processing includes, for example, sorting processing, punching processing, folding processing, and saddle stitching processing on printed paper.

  The paper P discharged from an image forming apparatus (not shown) is continuously conveyed to the paper feed roller 11 and sent to the paper buffer unit 3 by the paper feed roller 11. Here, in the paper P fed by the paper supply roller 11, the conveyance leading end side is defined as the sheet leading end, and the conveyance trailing end side is defined as the sheet trailing end. Further, the direction orthogonal to the transport direction is defined as the width direction, and the transport direction is defined as the vertical direction.

  The buffer unit 3 holds one or a plurality of sheets P on a pair of standby trays 31 arranged to face each other in the width direction, and abuts the paddle 32 on the rear end to align the vertical direction. The pair of standby trays 31 are inclined upward on the front end side of the paper, and the paper P discharged to the standby tray 31 by the paper feed roller 11 is lowered until the rear end thereof contacts the paddle 32. When transporting the second sheet P to the buffer unit 3, the first chuck unit 33 grips the rear end portion of the sheet P previously placed on the standby tray 31. Further, when the pair of standby trays 31 carry both ends of the paper P in the width direction and move in the direction in which the opposing interval is widened, the paper P carried is dropped and supplied to the lower processing tray 51.

  As shown in FIGS. 2 and 4A and 4B, as shown in FIG. 2, the first chuck portion 33 is disposed between a pair of paddles 32 arranged to face each other in the width direction. In the first chuck portion 33, a base portion 33a is rotatably attached to a support shaft 34 extending in the width direction, and a flat chuck plate 33b extends outward from the base portion 33a. The first chuck portion 33 is driven by the first chuck driving portion 35 so as to reciprocate around the support shaft 34 at a predetermined angle. The first chuck driving unit 35 reciprocally rotates the base 33a via the link 35b by an electromagnetic solenoid 35a that is a driving source, so that the chuck plate 33b is separated from the gripping position and the gripping position of the paper P shown in FIG. Further, it is rotationally moved between the open positions shown in FIG.

  As shown in FIG. 5A, the paddle 32 is formed by a flat plate-like first paddle portion 32b that forms a pedestal portion on which the rear end portion of the paper P is placed on the outer periphery of the base portion 32a, and a flat rubber member. The second paddle portion 32c, the third paddle portion 32d formed of a flat plate rubber member, and the fourth paddle portion 32e formed of a flat plate mylar member are arranged at a predetermined interval in the circumferential direction. The second paddle portion 32c is disposed behind the first paddle portion 32b when viewed in the rotational direction, the third paddle portion 32d is disposed behind the second paddle portion 32c, and the fourth paddle portion 32e is disposed behind the third paddle portion 32d. The The base portion 32a is rotatably arranged on the support shaft 34, for example, and is intermittently driven by a paddle drive portion (not shown).

  In the present embodiment, a position where the first paddle portion 32b waits for the rear end portion of the paper P to be placed is set as a standby position. When a predetermined number of sheets P are sent to the sheet buffer unit 3, the facing distance between the pair of standby trays 31 is increased and the sheet P is dropped, but the paddle driving unit moves the paddle unit 32 in one direction from the standby position. Rotate to stop the first paddle part 32b again at the standby position.

  The paddle 32 waits at an inclined position where the first paddle portion 32 b is substantially parallel to the standby tray 31 in a standby state where the paper P is held on the standby tray 31. When the first sheet P is placed with its rear end aligned with the pair of first paddle portions 32b with the rear end aligned, the first chuck portion 33 rotates the chuck plate 33b from the open position to the gripping position. Let The gripping position of the chuck plate 33b is a position where the paper P placed on the first paddle portion 32b in the standby state is slightly sandwiched between the pair of first paddle portions 32b. In this way, by grasping the rear end of the first sheet P, when the second sheet P is discharged by the paper feed roller 11, the leading end of the second sheet P is the first sheet. The first sheet P is prevented from being pushed forward by frictional contact with the other sheet P.

  The first paddle portion 32b is formed of a hard resin such as polyoxymethylene (POM) resin. As the paddle portion 32 starts to rotate, the rear end portion of the paper P is no longer supported by the first paddle portion 32b, and the rear end portion of the paper P falls while floating in the air, but the second paddle portion 32c that rotates rotates the paper. The rear end of P is scraped down and the paper P is placed on the processing tray 51. The second paddle part 32 c is set to a length that allows the paper P to be scraped off onto the processing tray 51.

  Subsequently, the rotating third paddle portion 32d comes into contact with the paper P placed on the processing tray 51, and slides until the rear end of the paper P comes into contact with the stopper portion 52 disposed rearward by frictional force. The trailing edge of the paper is aligned. For this reason, the 3rd paddle part 32d is formed longer than the 2nd paddle part 32c. Further, the paddle part 32 rotates, and the rotation stops in a state where the first paddle part 32b reaches the standby position. In this state, the fourth paddle part 32e is in pressure contact with the uppermost sheet P of the sheets P stacked on the processing tray 51, and the sheet P on the processing tray 51 is inadvertently pushed forward. This prevents the sheet from being misaligned.

  Since the fourth paddle portion 32e is formed of a Mylar sheet, the elastic force is weak, and when the paper P is dropped and supplied from the paper buffer portion 3 to the paper P stacked on the processing tray 51, Since the paper transport force directed forward is hardly applied to the fall-supplied paper P, the paper P on the processing tray 51 does not move depending on the fall-supplied paper P, and the consistency is maintained.

  However, when a large paper conveyance force directed forward is generated on the paper P supplied from the paper buffer unit 3, the paper P on the processing tray 51 is aligned with the holding force of the fourth paddle unit 32e. There is a risk that it cannot be held in position.

  Therefore, in the present embodiment, the paper P stacked on the processing tray 51 is forcibly held at the alignment position by the second chuck unit 60.

  The processing tray 51 aligns and holds the stacked paper P while the paper P is stapled by the stapler unit 7 which is a processing mechanism for performing post-processing, for example. As shown in FIG. 3, the sheets stacked on the processing tray 51 are aligned in the horizontal direction by a pair of opposed horizontal alignment plates 55 and 55 that can move in the direction of arrow V according to the width of the sheet P. .

  The second chuck part 60 is disposed below the paddle part 32 in order to avoid interference with the stapler part 7. The second chuck portion 60 includes, for example, a second chuck body portion 63 in which a pressing plate 62 is attached to the tip of the arm portion 61 and a second chuck driving portion (not shown) that drives the arm portion 61. The second chuck body 63 reciprocates between a pressing position where the pressing plate 62 is in pressure contact with the upper surface of the uppermost sheet P stacked on the processing tray 51 and a retreating position where the pressing plate 62 retreats upward from the pressing position. It can be moved.

  When the paper P is supplied from the buffer unit 3 to the processing tray 51, the second chuck unit 60 presses and holds the paper on the processing tray 51, the rotation of the paddle unit 32 is started, and the first paddle unit 32b While it stops at the standby position again, it retracts to the retract position, and when the first paddle portion 32b stops at the standby position, it moves to the pressing position.

  For example, the second chuck portion 60 has an arm portion 61 attached to a link mechanism or cam mechanism (not shown) that is reciprocally driven by a driving source such as an electromagnetic solenoid, and moves the pressing plate 62 up and down between a retracted position and a pressing position. It is configured.

  Even if the number of sheets stacked on the processing tray 51 increases and the sheet stacking height increases, the second chuck unit 60 stops the downward movement of the pressing plate 62 when the pressing plate 62 presses the sheet. The sheet can be held with a constant pressing force. For example, the pressing plate 62 is urged against the arm portion 61 by a spring member (not shown), and the pressing plate 62 is brought into contact with the sheet by the spring member. It moves against the spring force. When the movement of the pressing plate 62 is detected, the drive source of the second chuck unit 60 is stopped. The pressing plate 62 has an outer circumferential surface formed in an arc shape so as to avoid interference with the rear end of the paper P that has been scraped off by the second paddle portion 32c.

  On the other hand, for example, when two sheets P are held on the pair of standby trays 31, the sheet buffer unit 3 drops and supplies these two sheets P at a time. However, as the processing speed of the image forming apparatus increases, the processing speed of the post-processing apparatus 1 is also increased, and it is desired to perform the post-processing of the sheet at the processing speed of the image forming apparatus. In this case, for example, the first sheet is made to wait for two sheets of paper P to stand by in the standby tray 31 of the sheet buffer unit 3 and then the pair of standby trays 31 to operate to simultaneously drop the two sheets of paper P. With the P waiting in the standby tray 31, the pair of trays 31 are opened before the second sheet P is discharged by the paper feed roller 11 with the rear end held by the first chuck portion 33. The paper P is dropped. In this case, as shown in FIG. 5B, the leading edge of the first sheet P abuts on the sheet P on the processing tray 51.

  Then, the second sheet P is discharged directly from the sheet feed roller 11 onto the first sheet P, and the paddle section 32 is driven to rotate. In this case, the time until the two sheets of paper P fall on the processing tray 51 and are placed is shortened, and the processing speed of the post-processing apparatus 1 can be improved. At that time, since the sheet P or the sheet bundle on the processing tray 51 is held by the second chuck unit 60, the frictional force accompanied by the conveying force in the sheet conveying direction of the sheet P dropped from the sheet buffer unit 3. Does not move to the front end side of the paper, and the consistency is maintained.

  In this case, since the standby tray 31 functions to hold the rear end portion of the first sheet P by the first chuck portion 33, the first sheet P discharged from the sheet feed roller 11 is padded with the paddle 32. If the rear end portion of the sheet P can be gripped by the first chuck portion 33 and guided to the first paddle portion 32b, the pair of standby trays 31 becomes unnecessary.

  The paper P stacked on the processing tray 51 is aligned in the vertical direction with the rear end abutted against the stopper unit 52, and when a predetermined number of sheets P are stacked on the processing tray 51, the stapler unit 7 It moves along the width direction, and the stapling process is performed at a predetermined position. When the stapling process is completed, the stopper unit 52 moves forward, and the sheet bundle is moved onto the processing tray 51.

  As shown in FIG. 3, a transport belt 53 that transports paper to the paper discharge tray unit 9 is disposed at the center in the width direction of the processing tray 51. A sheet feeding claw 54 is attached to the conveyance belt 53 to hook the sheet bundle on the processing tray 51 and convey it to the sheet discharge tray unit 9. Note that the stacked sheets that are not subjected to the stapling process are similarly conveyed to the sheet discharge tray unit 9 by the sheet feeding claw 54.

  A plurality of paper discharge trays 91 are inclinedly disposed on the tray support portion 92 in the paper discharge tray portion 9, and each paper discharge tray 91 can be moved vertically with respect to the tray support portion 92 by a paper discharge tray drive portion (not shown). Is arranged. A paper discharge roller 93 is disposed at the transport end of the processing tray 51, and the paper P transported from the processing tray 51 is discharged to the selected paper discharge tray 91 by the paper discharge roller 93.

  A slight gap is formed between the rear end of the paper discharge tray 91 and the paper abutting and aligning plate 94 slidable in the vertical direction provided on the tray support portion 92, and the paper stacked on the paper discharge tray 91. Alternatively, the rear end of the sheet bundle comes into contact with the sheet abutting alignment plate 94, and vertical alignment is performed.

  Since the discharge tray 91 is inclined such that the front end side is obliquely upward, the discharged paper P or the sheet bundle slides down along the inclined surface, and the rear end thereof is the lower end of the discharge tray 91. Backward alignment is performed by abutting against a sheet abutting plate 94 provided on the tray support 92.

  When the paper P is continuously discharged to the paper discharge tray 91 or when the paper bundle is discharged, the paper P is already discharged onto the paper discharge tray 91 and placed on the surface of the paper stack or paper bundle. The sheet P or sheet bundle moving in the sheet discharge direction is brought into contact with the roller 93, and the sheet or sheet bundle on the sheet discharge tray 91 is pushed forward, so that the vertical alignment is shifted. In particular, since the sheet bundle is heavier than the case where two or three sheets of paper P are stacked and discharged, the sheets on the discharge tray 91 are more easily pushed out.

  In the present embodiment, the paper P placed on the paper discharge tray 91 is held by the third chuck unit 70, and the paper P or paper bundle placed on the paper discharge tray 91 is conveyed by the conveying force of the paper to be discharged. Prevents extrusion.

  The first chuck unit 33, the second chuck unit 60, and the third chuck unit 70 are disposed on the inner side of the minimum sheet size length L in the sheet transport direction.

  The third chuck part 70 has a paper abutting part 71 disposed below the paper discharge position in the vertical direction by the paper discharge roller 93. The sheet abutting portion 71 projects forward from the sheet abutting plate 94.

  The sheet abutting portion 71 forms a sheet abutting surface 73 parallel to the sheet discharge tray 91 so as to face the sheet discharge tray 91. Further, the sheet abutting alignment plate 94 is disposed within a range where the rear end of the sheet or sheet bundle loaded between the sheet abutting surface 73 of the sheet abutting portion 71 and the sheet discharge tray 91 comes into contact, for example, The paper discharge roller 93 positioned above the abutting portion 71 can also serve as a gate for closing the paper discharge port 95 through which the paper is discharged. In this embodiment, when the sheet is discharged from the discharge port 95, the sheet abutting alignment plate 94 moves downward to open the discharge port 95, and when the discharge of the sheet is completed, it moves upward to be discharged. The paper mouth 95 is closed. A notch (not shown) is formed in the paper abutting alignment plate 94 at a portion corresponding to the paper abutting portion 71 so as not to interfere with the upward movement of the paper abutting alignment plate 94.

  In a state where the paper P is placed, the paper discharge tray 91 rises until the upper surface of the paper P comes into contact with the paper abutting surface 73 of the paper abutting portion 71. The paper P is sandwiched between and held. When the paper P or the paper bundle is discharged from the paper discharge roller 93, the paper discharge tray 91 moves downward, and the gap where the discharged paper P or the paper bundle enters the paper abutting surface 73 To hold the paper to be raised and stacked again.

  In the present embodiment, the outer peripheral surface 72 of the sheet abutting portion 71 is formed as an inclined surface, and even if the trailing edge of the sheet P or the sheet bundle ejected from the sheet ejection roller 93 falls, the sheet is ejected without any problem. Placed on the tray 91.

  Note that a member constituting the sheet abutting surface 73 may be biased by the spring member with respect to the sheet abutting portion 71, and the sheet may be held by applying the spring force of the spring member. In this case, the raising operation of the paper discharge tray 91 may be stopped by detecting the movement of the member constituting the paper abutting surface.

  As described above, the sheet post-processing apparatus 1 according to the present embodiment holds the sheet P to be waited in the buffer unit 3 by the first chuck unit 33, prevents extrusion by the next sheet to be supplied, and performs vertical alignment. Maintaining and dropping to the processing tray 51 of the processing tray unit 5. At that time, since the sheet or sheet bundle placed on the processing tray 51 is maintained in the aligned state at the rear end thereof and held by the second chuck unit 60, it is moved forward by contact with the sheet supplied from the buffer unit 3. It will not be pushed out.

  Further, when the sheets or sheet bundle stacked on the processing tray 51 are discharged to the sheet discharge tray unit 9, the sheet or sheet bundle placed on the sheet discharge tray 91 is held by the third chuck unit 70. It is prevented from being pushed forward by contact with a sheet or a bundle of sheets discharged and conveyed by the discharge roller 93.

  Accordingly, the sheets or sheet bundles discharged and stacked on the discharge tray 91 are not disturbed in the vertical direction in the buffer unit 3, the processing tray unit 5, and the discharge tray unit 9, respectively. In addition, the sheets that have been discharged to the discharge tray 91 are stacked while maintaining the alignment in the vertical and horizontal directions. Although the sheet post-processing apparatus of this embodiment has been described separately from the image forming apparatus, it may be provided integrally with the image forming apparatus.

  The present embodiment can be implemented in various other forms without departing from the spirit or main features thereof. Therefore, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is indicated by the scope of claims, and is not restricted by the text of the specification. Further, all modifications, various improvements, alternatives and modifications belonging to the equivalent scope of the claims are all within the scope of the present invention.

P Paper 1 Paper post-processing device 3 Paper buffer part 5 Processing tray part 51 Processing tray 52 Stopper part 7 Stapler part 9 Paper discharge tray part 91 Paper discharge tray 32 Paddle 33 First chuck part 60 Second chuck part 70 Third chuck part

Claims (4)

A buffer unit for waiting for paper fed from the image forming apparatus;
A processing tray unit that is disposed below the buffer unit, has a processing tray to which paper is supplied from the buffer unit, and allows the paper that has been supplied from the buffer unit to the processing tray and stacked thereon to be conveyed in the discharge direction. When,
A post-processing unit that performs post-processing on the paper stacked on the processing tray;
A paper discharge tray portion having a paper discharge tray from which a bundle of post-processed sheets stacked on the processing tray is discharged;
A first chuck portion for holding a rear end of the paper waiting in the buffer portion;
A second chuck part comprising a second chuck body part for holding the rear end of the paper placed on the processing tray, and a second chuck drive part for driving the second chuck body part;
A third chuck portion for holding a rear end of the paper placed on the paper discharge tray;
Have
The buffer unit feeds the next sheet on the sheet held by the first chuck unit, and the processing tray unit is formed on the sheet held by the second chuck unit from the buffer unit. The paper is supplied, and the paper discharge tray unit discharges the paper from the processing tray unit onto the paper on the paper discharge tray held by the third chuck unit, and the second chuck driving unit The second chuck is configured to move between a pressing position for holding the sheet by pressing and contacting the upper surface of the uppermost sheet stacked on the processing tray and a retreating position for retracting upward from the pressing position. Drive the body ,
The buffer unit discharges the next sheet onto the first sheet in a state where the first sheet is held by the first chuck unit, and the second chuck unit receives the first sheet from the buffer unit. A paper post-processing device that holds paper on the processing tray when the next paper is supplied to the processing tray . The sheet post-processing apparatus according to claim 1 , wherein the buffer unit drops and supplies a plurality of sheets stacked on a standby tray to the processing tray. 2. The buffer section feeds the next sheet onto the sheet in a state where the leading end side of the sheet held by the first chuck section is in contact with the sheet on the processing tray. Or the sheet post-processing apparatus according to 2; The third chuck portion is configured to allow the sheet discharge tray to move up and down, and a sheet abutting section for holding the sheet by abutting the upper surface of the rear end of the sheet placed on the sheet discharge tray when the sheet discharge tray is raised. sheet post-processing apparatus according to any one of claims 1 to 3, characterized in that it has.

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