JP4143524B2 - Paper stacking mechanism and post-processing apparatus equipped with the mechanism - Google Patents

Description

  The present invention relates to a paper stack mechanism that discharges paper after aligning processing for aligning paper bundles while receiving and temporarily storing paper in a stack section that has been sequentially conveyed, and a post-processing apparatus including the mechanism. .

  Conventionally, a post-processing apparatus as shown in FIG. The post-processing apparatus 100 includes a box-shaped casing 101 that receives paper P discharged from another device such as an image forming apparatus, and an oblique arrangement in the casing 101, for example, stapling processing. A post-processing unit 102 that performs post-processing on the paper bundle P1, and a plurality of stages that are provided outside the housing 101 so as to face the post-processing unit 102 and receive the paper P or the paper bundle P1 discharged from the post-processing unit 102. The job tray 103 is configured.

  A take-off roller pair 104 is provided on the side wall of the case 101 to take the paper P discharged from another device into the case 101, and the case 101 is provided with a take-off roller pair 104. The conveyance path 105 for guiding the paper P introduced in this way to the post-processing unit 102 to an intermediate position, and a pair of paper discharge rollers 106 arranged at a position facing the post-processing unit 102 at the downstream end of the conveyance path 105. Is provided. Therefore, the paper P introduced into the housing 101 via the take-up roller pair 104 passes through the transport path 105 and is discharged to the post-processing unit 102 via the paper discharge roller pair 106.

  The post-processing unit 102 includes a unit main body 102a that is disposed obliquely so that the upper end faces the job tray 103, and a paper support plate 102b that supports a paper bundle P1 that protrudes from the lower upper surface of the unit main body 102a. And a stapling device 102c provided above the sheet support plate 102b and at a position where the sheet bundle P1 can be sandwiched between the unit main body 102a. Then, the sheet bundle P1 supported by the sheet support plate 102b on the unit main body 102a via the pair of discharge rollers 106 is stapled by the stapling device 102c, and is then driven in advance by driving the discharge mechanism (not shown). Paper is discharged toward the job tray 103 set at a predetermined height position (that is, a paper discharge destination tray is set).

  In the post-processing apparatus 100 configured as described above, a brush roller in which a large number of hairs are implanted in the radial direction around the horizontal axis, particularly between the discharge roller pair 106 and the unit main body 102a. 107 is disposed, and the brush roller 107 is discharged onto the unit main body 102a through the discharge roller pair 106 by the clockwise rotation around the horizontal axis in FIG. 7, and is supported by the paper support plate 102b. The rear edge (upper side in FIG. 7) of the sheet P is pressed toward the unit main body 102a.

By adopting the brush roller 107, the paper P discharged to the unit main body 102a of the post-processing unit 102 via the paper discharge roller pair 106 is pushed by the brush roller 107 toward the unit main body 102a. Since the sheet P is bent, the so-called page misalignment in which the sheet P newly inserted is inserted between the sheet bundles P1 on the unit main body 102a on which the sheet P has already been formed and the order of the pages is changed does not occur.
JP 2000-159421 A

  However, since the brush roller 107 in the state described in Patent Document 1 is rotated when the paper P is received, it is always in contact with the upper edge of the paper bundle P1 in which the bristles of the brush roller 107 are stored. As a result, a harsh sound such as “crisp” is generated, and it is impossible to obtain a calm work environment due to this noise.

  Further, since the brush roller 107 is more expensive than a normal roller, there is a problem that the parts cost increases.

  Further, the brush roller 107 is prone to wear on the hair and has a short service life compared to a normal roller. Therefore, the brush roller 107 is frequently replaced with a new one, thereby increasing the running cost.

  In addition, since only the upper edge portion of the sheet bundle P1 supported by the sheet support plate 102b on the unit main body 102a of the post-processing unit 102 is mixed by the brush roller 107, alignment for aligning the end edges of the sheet bundle P1 is performed. There is also a problem that it cannot be performed with high accuracy.

  The present invention has been made in view of such a situation, and does not generate annoying noise, contributes to reduction of parts cost and running cost, and can realize high-precision alignment processing of a sheet bundle. It is an object of the present invention to provide a stack mechanism and an aftertreatment device including the mechanism.

According to the first aspect of the present invention, there is provided a stack unit including a standing-type sheet receiving plate that temporarily stores a sheet to be conveyed, and the sheet is discharged to the stack unit each time the sheet is discharged to the stack unit. A sheet urging member that urges the sheet toward the receiving plate, a sheet elevating member that is provided in the stack unit and moves up and down between the upper position and the lower position along the sheet receiving plate; A posture maintaining member that maintains the posture of the stored paper along the side of the paper receiving plate in a state where the stored paper is raised to the upper position by the paper elevating member and the urging by the paper urging member is released; , following the paper in a state where the storage sheet is maintained posture and the posture maintaining member is raised to the upper position by the paper lift member is discharged paper stack part, the paper urging member after the sheet discharge While energizing the paper, The paper lifting member storing paper in the attitude retainer is a sheet stacking mechanism, characterized in that it is configured to descend in order to direct the lower position not maintained posture.

  By adopting such a configuration, when the storage sheet rises to the upper position due to the rising of the sheet elevating member, the rear end (upper edge) of the storage sheet is guided to the posture maintaining member and guided toward the sheet receiving plate. In this state, since the next sheet is discharged to the stack section, the next sheet is discharged to the stack section without interfering with the upper edge portion of the storage sheet, so that the next sheet is placed between the storage sheets. The page misalignment caused by fitting in is reliably prevented.

  Then, after the next sheet is discharged to the stacking section, the sheet urging member urges the rear end of the stored sheet, and the sheet elevating member descends to direct the stored sheet to the lower position. The paper stored in the section is overlapped on the already-stored storage paper without any gap, thereby avoiding a state in which only new paper is separated from the storage paper.

  Further, each time a new sheet is discharged to the stack unit, the stored sheet is moved up and down between the upper position and the lower position by driving the sheet elevating member. Alignment processing in which the end portions of the storage sheets are aligned by an impact (inertial force) when the elevating member suddenly stops is reliably performed.

  In this way, the paper elevating member moves up and down in synchronism with the timing of receiving the paper, thereby eliminating the page misalignment of the stored paper and suppressing the generation of annoying noise because the brush roller is not used. In addition, since the expensive brush roller is not used, it is possible to contribute to the reduction of the component cost at the time of manufacture and the running cost at the time of use, and the highly accurate alignment processing of the storage paper can be realized.

  According to a second aspect of the present invention, in the paper stacking mechanism according to the first aspect, the paper urging member presses a rear end portion in the paper discharge direction. .

  By adopting such a configuration, the paper can be effectively urged toward the paper receiving plate at a pinpoint.

According to a third aspect of the present invention, there is provided a stack unit including a standing-type sheet receiving plate that temporarily stores the conveyed sheet, and the sheet is discharged to the stack unit each time the sheet is discharged to the stack unit. A sheet urging member that urges the sheet toward the receiving plate, a sheet elevating member that is provided in the stack unit and moves up and down between the upper position and the lower position along the sheet receiving plate; A posture maintaining member that maintains the posture of the stored paper along the side of the paper receiving plate in a state where the stored paper is raised to the upper position by the paper elevating member and the urging by the paper urging member is released; the position maintaining member is I Oh the guide plate covered state with respect to the sheet bundle coming raised the sheet receiving plate side guide roller of the guide rollers for guiding the sheet to the stack unit, reservoir The paper is raised to the upper position In this state, the next sheet is discharged to the stack portion, and after the sheet discharge, the sheet urging member urges the sheet, and the sheet elevating member descends to direct the stored sheet toward the lower position. It consists a sheet stacking mechanism, characterized in Rukoto.

  By adopting such a configuration, the upper edge of the stored paper that is directed upward by the drive of the paper elevating member is guided by the guide plate covered with the guide roller on the paper receiving plate side, and is surely directed in the direction of the paper receiving plate. You can make it.

According to a fourth aspect of the present invention, there is provided a stack unit including a standing-type sheet receiving plate that temporarily stores the conveyed sheet, and the sheet is discharged to the stack unit each time the sheet is discharged to the stack unit. A sheet urging member that urges the sheet toward the receiving plate, a sheet elevating member that is provided in the stack unit and moves up and down between the upper position and the lower position along the sheet receiving plate; A posture maintaining member for maintaining the posture of the stored paper along the paper receiving plate in a state where the stored paper is raised to an upper position by the paper elevating member and the urging by the paper urging member is released; and a control section for controlling the drive of the biasing member and the sheet lifting member, is provided, wherein the control unit is directed to the upper position the sheet lifting member from the lower position, the paper urging member urges the sheet, and , Posture maintaining member is stored paper A first state in which the posture is maintained to prepare for receiving the paper, and the paper urging member is urged by the paper urging member in a state where the paper elevating member is located at the upper position and the action of the posture maintaining member is continued. Is released and the paper is started to be received, and the paper urging member is biased by the paper urging member in a state where the paper elevating member is moved from the upper position to the lower position and the action of the posture maintaining member is released. A third state in which the paper storage operation is performed after being released;
A fourth state in which the paper urging member urges the paper in a state where the paper elevating member is located at the lower position and the release of the action of the posture maintaining member is continued is performed. This is a paper stack mechanism.

  By adopting such a configuration, based on the control of the control unit, the sheet elevating member and the sheet urging member perform a predetermined operation in cooperation with each other while obtaining a predetermined action of the posture maintaining member, and perform the first operation on the sheet. The first to fourth states appear one after another, and in particular, from the second state in which the paper elevating unit is in the upper position and the paper is received, the third state in which the paper elevating member is lowered toward the lower position. When the sheet is displaced to the state, the upper and lower ends of the bundle of stored sheets formed by discharging the sheets to the stack portion are aligned by the impact (inertial force) at that time.

  In such control, a width direction aligning unit that aligns a bundle of sheets in the width direction by swinging in the width direction each time the sheet is discharged to the stack unit is provided, and driving of the width direction aligning unit is performed. If the control is performed, the sheet bundle formed in the stack portion is aligned in both the vertical direction and the width direction. In this case, as the width direction aligning means, a non-oscillating width direction restricting member that restricts only movement in the width direction of the sheet according to the sheet size is provided, and the position of the width direction restricting member is set according to the sheet size. Thus, the side edges in the width direction of the bundle of sheets may be aligned.

  According to a fifth aspect of the present invention, there is provided a post-processing apparatus in which the paper stacking mechanism according to any one of the first to fourth aspects is adopted, and a predetermined amount of paper is stored in the stacked portion and aligned. The post-processing apparatus is configured to perform processing.

  By adopting such a configuration, the post-processing apparatus enjoys the functions and effects provided by the paper stack mechanism according to any one of claims 1 to 4.

  According to the first aspect of the present invention, the sheet raising / lowering member is moved up and down in synchronization with the sheet receiving timing, so that the page misalignment of the stored sheet is eliminated and the brush roller is not used. It is possible to suppress the occurrence and contribute to the reduction of the cost of parts at the time of manufacture and the running cost at the time of use because the expensive brush roller is not used. Can be realized.

  According to the second aspect of the present invention, the paper can be effectively urged toward the paper receiving plate at a pinpoint.

  According to the third aspect of the present invention, the upper edge portion of the storage sheet that is directed upward by the driving of the sheet elevating member is guided to the guide plate that is covered with the guide roller on the sheet receiving plate side. You can be sure to face the direction of the board.

  According to the fourth aspect of the present invention, the paper is discharged to the stack portion by a series of linked operations of the paper elevating member and the paper urging member based on the control of the control device based on the predetermined action of the posture maintaining member. By doing so, the end portions in the vertical direction of the storage sheets formed can be aligned.

  According to the invention described in claim 5, the post-processing device can enjoy the function and effect provided by the sheet stack mechanism according to any one of claims 1 to 4.

  FIG. 1 is a side view for explaining the internal structure of an embodiment of a post-processing apparatus according to the present invention. As shown in this figure, the post-processing apparatus 10 of this embodiment is provided adjacent to a copying machine, a facsimile machine, and an image forming apparatus 19 applied as various printers, and has a vertically long box shape. A punch unit 12 that performs punching processing for punching a binding hole in the paper P along the paper transport path R in the case 11 that is presented, and a downstream side (left side in FIG. 1) of the punch unit 12 are provided. The paper sorting unit 13 that sorts the paper P by destination and the bundle of discharged paper P (sheet bundle P1 (storage paper)) disposed under the paper sorting unit 13 are temporarily stored, and A stack unit 20 that performs a stapling process for binding the sheet bundle P1 to the sheet bundle P1 and a center folding unit 16 that performs a folding process on the sheet bundle P1 after the stapling process are provided.

  On the other hand, outside the casing 11, a job tray 14 erected on the back side of the casing 11, a general-purpose tray 15 disposed below the job tray 14, and a casing facing the general-purpose tray 15. 11 and a half-fold tray 17 disposed at the lower end portion. On the job tray 14 and the general-purpose tray 15, the sheet P and the sheet bundle P <b> 1 that are not subjected to the middle folding process are discharged, whereas the middle folding tray 17 is subjected to the middle folding process in the middle folding processing unit 16. The sheet bundle P1 is discharged.

  The sheet conveyance path R is a sheet transfer for transferring the sheet P discharged from the sheet discharge port 191 of the image forming apparatus 19 provided at the upper part of the front side (right side in FIG. 1) of the housing 11. An entrance-side transport path R1 from the opening 111 toward the paper distribution section 13, an annular transport path R2 formed in the paper distribution section 13 following the entrance-side transport path R1, and an upward rear portion from the annular transport path R2. Branched transport path R3 for job tray, transport path R4 for general-purpose tray branched from the paper sorting section 13 to the general-purpose tray 15 below the transport path R3 for job tray, and stacking section from the paper sorting section 13 The stack portion transport path R5 hanging down toward the stack 20, the stack section transport path R6 formed so as to vertically pass through the stack section 20, and the stack section transport path R6 can communicate with each other. In the middle folding processing section 16 in a slanted state, and a carry-out path for carrying out the sheet bundle P1 subjected to the middle folding processing in the middle folding processing section 16 It consists of a transport path R8.

  Each of the sheet sorting sections 13 is provided with a switching member for switching the conveyance path at an appropriate position, and the inlet-side conveyance path R1 from the image forming apparatus 19 through the sheet transfer opening 111 by a predetermined switching operation of these switching members. The paper P discharged inside is sent to a target location through a preset conveyance path.

  The punch portion 12 is provided above the entrance-side transport path R1. The punch unit 12 includes a punch mechanism 121 that raises and lowers the punch blade, and the sheet P introduced into the entrance-side transport path R1 is punched by driving the punch mechanism 121 in a state where transport is temporarily stopped. A punch hole is drilled at a predetermined position by raising and lowering the blade.

  The paper sorting unit 13 has a retracting drum 131 for directing the paper P fed from the entrance-side transport path R1 to the stack-part transport path R5. The retracting drum 131 smoothly prevents the sheet P from being bent at a substantially right angle when the sheet P is directed directly from the entrance-side transport path R1 to the stack-part transport path R5. The sheet P is transported to the stack portion without causing a large change in angle by causing the sheet P to follow the peripheral surface by rotation in the clockwise direction around the axis. Introduced in R5.

  A guide roller pair R51 that pushes the sheet P toward the in-stack conveyance path R6 is provided at a substantially intermediate position of the conveyance path R5 for the stack section. The sheet P is stably fixed by driving the guide roller pair R51. It is introduced into the in-stack conveyance path R6 in a speed state.

  The job tray 14 includes a plurality of unit trays 141 arranged in parallel at a predetermined interval in the vertical direction, and any one of the unit trays 141 can be selected according to the type of job. For this selection, the job tray 14 is configured so that it can be moved up and down along a column 112 erected on the back surface of the housing 11. When a desired unit tray 141 is selected, the base of the unit tray 141 is selected. The end side is set at a position facing the downstream end of the job tray transport path R3. Therefore, the sheet P discharged through the job tray transport path R3 is discharged to the unit tray 141 selected in advance.

  The general-purpose tray 15 is a general paper P that is discharged through a paper tray P1 or a paper bundle P1, that is, the general-purpose tray transport path R4, in particular, the unit tray 141 that is the discharge destination in the job tray 14 is not selected. In addition, the sheet bundle P1 that has been subjected to the predetermined post-processing in the intra-stack conveyance path R6 is received, and the base end side of the bundle is opposed to the downstream end of the general-purpose tray conveyance path R4.

  The stack unit 20 temporarily stores the paper P sequentially introduced into the intra-stack conveyance path R6 through the conveyance path R5 for the stack part to form a paper bundle P1, and the formed paper bundle P1 An alignment process for aligning the edges and a so-called stapling process for binding the sheet bundle P1 are performed. The transport path R5 for the stack portion is opposed to a position slightly above the intermediate position of the intra-stack transport path R6, while the upper end of the intra-stack transport path R6 is opposed to the general-purpose tray transport path R4. Yes.

  Accordingly, the paper P once introduced into the intra-stack conveyance path R6 through the stack conveyance path R5 is subjected to a stapling process as a paper bundle P1, and then the paper bundle P1 is transferred to the intra-stack conveyance path. The paper is discharged from the upper end of R6 to the general-purpose tray 15 via the general-purpose tray transport path R4.

  The center folding unit 16 is a part that performs a so-called center folding process, in which the sheet bundle P1 that has been stapled at the center by the stack unit 20 is folded at the center. 161 is provided.

  The middle folding unit 161 includes a middle folding roller pair 162 provided at the center upper portion of the middle folding portion conveyance path R7 and a middle folding roller provided at the lower portion of the middle folding portion conveyance path R7 so as to face the middle folding roller pair 162. A plate-shaped pressing die 163 that traverses the internal conveyance path R7, a carry-out roller pair 164 provided at the downstream end of the carry-out conveyance path R8, and swingable about a predetermined axis on the downstream side of the carry-out roller pair 164 The presser member 165 is provided.

  The pressing die 163 has a portion subjected to the stapling process in a state where the sheet bundle P1 is carried into the intermediate folding portion transport path R7 and is directed toward the middle folding roller pair 162 by driving of a driving unit (not shown). It is made to press. Accordingly, the sheet bundle P1 that has been folded in the middle by the pressing die 163 is drawn into the carry-out conveyance path R8 by driving the pair of folding rollers 162, and the carry-out conveyance path R8, the carry-out roller pair 164, and the like. The sheet is discharged to the half-fold tray 17 via the pressing member 165.

  Hereinafter, the stack unit 20 will be described in detail with reference to FIG. FIG. 2 is a schematic side view showing an embodiment of the stack unit 20 (post-processing unit 30). 2 shows a state in which the front side of FIG. 2 is removed from the pair of side plates in the width direction of each of the receiving unit 40 and the cover unit 50 (direction orthogonal to the paper surface of FIG. 2). Yes.

  First, as shown in FIG. 2, the stack unit 20 includes a receiving unit 40 that receives the paper P from the transport path R5 for the stack unit, and a cover unit 50 that covers the paper receiving surface of the receiving unit 40 so as to be openable and closable. The post-processing unit 30 is configured.

  The receiving unit 40 has a pair of widthwise directions arranged at an angle with the upper end facing the general-purpose tray transport path R4 and the lower end positioned at the lower right side of the housing 11. A sheet receiving plate 42 that receives the sheet P between the side plates 41, and a sheet that raises and lowers the sheet bundle P1 formed by being stacked on the sheet receiving plate 42 between an upper position and a lower position along the sheet receiving plate. An elevating member 43, a stapling mechanism 44 installed at a substantially intermediate position in the vertical direction between the side plates 41, and an endless belt 45 for elevating and lowering the paper elevating member 43 along the paper receiving plate 42 are interposed. Is made up of.

  A plurality of the sheet receiving plates 42 are arranged side by side in the width direction (direction orthogonal to the paper surface of FIG. 2), and the endless belt 45 for raising and lowering is disposed in the gap between the arranged sheet receiving plates 42. It is arranged in a fitted state. The sheet elevating member 43 is fixed to an elevating endless belt 45 provided between the sheet receiving plates 42, and is moved up and down along the sheet receiving plate 42 by forward and reverse rotation of the elevating endless belt 45. .

  FIG. 3 is a perspective view showing an embodiment of the paper lifting member 43. As shown in FIG. 3, the paper elevating member 43 includes a fixing portion 431 that is fixed to the elevating endless belt 45 in a straddling state and a U-shaped fixing portion 431 that is integrally connected to the fixing portion 431. A sheet bundle receiving portion 434 for receiving the bundle P1 is included.

  The fixing portion 431 is formed by folding a flat plate 432 having a width dimension substantially the same as that of the endless belt 45 for lifting and lowering from both sides in the width direction of the flat plate 432 toward the endless belt 45 for lifting. And a pair of side plates 433. The fixing portion 431 is fixed to the lifting endless belt 45 by bolting the flat plate 432 to the lifting endless belt 45 with the pair of side plates 433 sandwiching the lifting endless belt 45. .

  The sheet bundle receiving portion 434 is formed by extending from the vertical edge of the flat plate 432 of the fixed portion 431. The sheet bundle receiving plate 435 extending from the upper end edge of the flat plate 432, and the flat plate The upper edge portion of the sheet bundle receiving plate 435 extends from the lower edge portion 432 and is fixed to the leading edge of the sheet bundle receiving plate 435 by welding or the like.

  The sheet bundle receiving plate 435 is formed in a stepped shape in a side view, and further includes an abutting plate 435a to which the lower end edge of the sheet bundle P1 directly connected to the flat plate 432 abuts, and a leading edge of the abutting plate 435a. It is composed of an L-shaped plate 435b that is L-shaped in an extended side view and projects upward from the stopper plate 435a. A sheet bundle support space 437 is formed above the stop plate 435a and between the endless belt 45 for raising and lowering and the L-shaped plate 435b.

  The stapling mechanism 44 (FIG. 2) performs a stapling process on the sheet bundle P1 supported by the sheet elevating member 43 between the receiving unit 40 and the cover unit 50 of the post-processing unit 30. For example, a driving mechanism for driving the supplied binding needle into the sheet bundle P1, and the like are not described here.

  As shown in FIG. 2, the lifting endless belt 45 is wound around a predetermined number of belt support rollers provided between a pair of side plates 41, and is provided between the side plates 41 at a substantially intermediate position in the longitudinal direction. The belt is rotated by driving the belt motor 451. The belt support roller includes a drive roller 452 concentrically fixed to the drive shaft of the belt motor 451, and an endless belt for raising and lowering between the upper end portion, the lower end portion and the pair of side plates 41 between the pair of side plates 41. A predetermined number of driven rollers 453 provided at positions where 45 can be wound around the driving roller 452 are employed.

  Therefore, the endless belt 45 for raising and lowering rotates forward and backward between the driven rollers 453 via the driving roller 452 by forward and reverse driving of the belt motor 451, and thereby the sheet raising and lowering connected to the endless belt 45 for raising and lowering the sheet. The member 43 moves up and down along the sheet receiving plate 42.

  Further, as shown in FIG. 2, the sheet elevating member 43 is provided with a pair of paper bundle support positions between the receiving unit 40 and the cover unit 50 via the lowest roller 453a positioned at the lowest position among the driven rollers 453. It can move toward the retracted position, which is the lower position between the side plates 41. When the sheet elevating member 43 is positioned at the retracted position, the in-stack conveyance path R6 communicates with the in-folding section conveyance path R7, whereby the stapling mechanism 44 performs the stapling process for the middle folding (the central part of the sheet bundle P1). The sheet bundle P1 to which the sheet is stapled) can be directed to the in-folding section conveyance path R7.

  The cover unit 50 guides the receiving unit 40 to move up and down the sheet bundle P1 formed by discharging the paper P to the intra-stack conveyance path R6 and to face the paper receiving plate 42 of the unit 40. A pair of side plates 51 that are to be covered and are arranged so as to face the paper receiving plate 42 of the receiving unit 40 between the pair of side plates 51 and the pair of side plates 51. And a receiving portion 53 provided at a position facing the stapling mechanism 44. The receiving portion 53 serves as a receiving base when the stapling mechanism 44 applies a stapling process to the sheet bundle P1, and a clincher portion for a stapler for saddle stitching, which will be described later, is provided here. Yes.

  The cover unit 50 is pivotally supported around a roller shaft 453b that pivotally supports the lowest roller 453a, and rotates in the forward and reverse directions around the roller shaft 453b to close the intra-stack conveyance path R6. 2, the posture can be changed between a closed posture shown by a solid line and an open posture shown by a two-dot chain line in FIG.

  In the present invention, as shown in FIG. 2, the position is obliquely above the upper end portion of the cover unit 50 and is located immediately below the guide roller pair R51 and behind the stack portion transport path R5 (rightward in FIG. 2). ) Is provided, and a posture maintaining member 70 is provided at a position above the urging member 60 and in front of the roller in front of the guide roller pair R51.

  The biasing member 60 applies the rear edge (upper edge) of the paper P discharged to the intra-stack conveyance path R6 through the guide roller pair R51 toward the paper receiving plate 42 of the receiving unit 40. It is intended to help. In this state, the sheet elevating member 43 is raised, whereby the upper end portion of the sheet bundle P1 is guided between the posture maintaining member 70 and the sheet receiving plate 42. This is to prevent the sheet P that has reached the transport path R6 from interfering with the discharge of the sheet P that is sent next.

  In the alignment processing operation of the sheet bundle P1 by the lifting and lowering operation of the sheet lifting member 43, the posture maintaining member 70 is separated from the upper edge portion of the sheet bundle P1 in the direction from the intra-stack conveyance path R6 to the stack conveyance path R5. This is to prevent the flow backward, and in cooperation with the urging member 60, page misalignment of the sheet bundle P1 is prevented.

  FIG. 4 is a perspective view showing an embodiment of the urging member 60 and the posture maintaining member 70. In FIG. 4, the XX direction is referred to as the width direction, and the YY direction is referred to as the front-rear direction. In particular, the -X direction is referred to as the left, the + X direction is referred to as the right, the -Y direction is referred to as the front, and the + Y direction is referred to as the rear.

  As shown in FIG. 4, the urging member 60 includes a pair of side plates 61 that are long in the vertical direction, a front plate 62 that is laid between the front edges of the pair of side plates 61, and the front plate 62. The upper end plate 63 is formed by bending the front end portion thereof toward the upper edge portion of the pair of side plates 61.

  The base end portion (lower portion) of each side plate 61 is rotatable around a transverse shaft 113 installed on a predetermined frame of the casing 11 so as to cross a position slightly behind the transport path R5 for the stack portion in the width direction. Accordingly, the urging member 60 is shown in FIG. 2 and FIG. 4 by a solid line, and a paper receiving posture (standby posture) standing on the transverse shaft 113, and by a two-dotted line in FIG. 2 and FIG. The posture can be changed between a biasing posture in which the upper edge portion of the paper P is biased toward the paper receiving plate 42.

  The urging member 60 is provided with an L-shaped projecting piece 64 having an L-shape in a plan view, with the distal end side folded back in a state of slightly protruding rightward from the base end portion of the right side plate 61. On the other hand, an actuator 65 corresponding to the L-shaped projecting piece 64 is provided on a frame (not shown) of the housing 11, and an upper end portion of the operation rod 651 that moves in the vertical direction of the actuator 65 is connected via a connecting shaft 652. And connected to the tip of the L-shaped projecting piece 64. Therefore, when the operating rod 651 is moved forward and backward from the actuator 65 by the forward / reverse driving of the actuator 65, the urging member 60 rotates forward and backward around the transverse axis 113 via the L-shaped projecting piece 64. The posture is changed between the paper pressing posture indicated by the dotted line and the paper receiving posture indicated by the solid line.

  As shown in FIG. 4, the posture maintaining member 70 is fixed to a frame (not shown) so as to go to the general-purpose tray transport path R4 (FIG. 1) on the upper side of the roller in front of the guide roller pair R51. And an upper guide plate 71 that is long in the width direction, and a lower guide plate (guide plate) 72 that extends downward from the lower edge of the upper guide plate 71. Has been.

  The lower guide plate 72 is substantially in contact with the peripheral surface of the roller in front of the guide roller pair R51 on the upper surface side, thereby covering the lower front portion of the peripheral surface of the roller in front of the guide roller pair R51 obliquely. ing. The lower guide plate 72 is dimensioned so that the lower end edge thereof is positioned behind the front end edge of the upper surface plate 63 of the biasing member 60 set in the paper biasing posture.

  Accordingly, the upper end edge of the sheet bundle P1 that is rising in the in-stack conveyance path R6 as a result of the sheet elevating member 43 ascending while the urging member 60 is set to the urging posture is the front edge of the urging member 60. Since the sheet is guided by the face plate 62 and the lower guide plate 72 of the posture maintaining member 70 toward the general-purpose tray transport path R4, it is possible to reliably prevent the occurrence of inconvenience that a part of the sheet bundle P1 returns to the stack section transport path R5. Is done.

  Further, in the present embodiment, the staple mechanism 44 is the same as the end binding mode in which two appropriate positions in the width direction of the lower end edge of the sheet bundle P1 temporarily stored in the intra-stack transport path R6 are bound. A center binding mode (saddle stitching mode) for binding two appropriate positions in the width direction at the center in the vertical direction of the sheet bundle P1, and one side portion in the width direction at the lower edge of the sheet bundle P1 obliquely Three types of stapling modes can be selected, including a corner binding mode (flat binding mode) for binding.

  After the sheet bundle P1 is aligned, the height of the sheet elevating member 43 is set according to the sheet size and a preset stapling process mode, and the sheet bundle P1 is driven by the subsequent driving of the stapling mechanism 44. In contrast, stapling is performed at a position corresponding to a preset stapling mode.

  When the stapling mechanism 44 is set to the end binding mode or the corner binding mode, the sheet bundle P1 after the end of the stapling process is transferred to the general-purpose tray 15 via the general-purpose tray transport path R4. On the other hand, when the staple mechanism 44 is set to the center binding mode, the sheet bundle P1 after the end of the stapling process is directed to the middle folding processing unit 16 via the middle folding unit conveyance path R7. In this case, after the predetermined half-folding process is performed, the sheet is discharged to the half-folding tray 17.

  Further, in the present embodiment, there is provided a width direction aligning unit (not shown) for the sheet bundle P1 temporarily stored in the intra-stack conveyance path R6. This width direction aligning means includes a pair of swing members that swing in the width direction corresponding to the paper size, and each time the paper P is discharged to the intra-stack conveyance path R6, these swing members. Oscillates so as to sandwich the sheet P from the left and right, and thereby the alignment process in the width direction of the sheet bundle P1 is performed.

  Incidentally, the width direction aligning means is not limited to including the swing member, but a pair of width direction restricting members is provided instead of the swing member, and the inner dimension between the pair of width direction restricting members is determined. You may change only according to paper size. By doing so, the sheet P discharged to the intra-stack conveyance path R6 is regulated by the pair of width direction regulating members, thereby realizing alignment in the width direction.

  FIG. 5 is an explanatory diagram for explaining the operation of the alignment process of the sheet bundle P1 in the post-processing unit 30 in the post-processing apparatus 10 according to the present invention. FIG. The state immediately after being discharged to the path R6 (third state) and (b) are the states in which the sheet P discharged into the in-stack conveyance path R6 is lowered by the lowering of the sheet lifting member 43 (fourth state). (State), (C) is a state in which the paper P once lowered in the intra-stack conveyance path R6 is raised by the ascending / descending member 43 (first state), and (D) is a state in which the next paper P is in the stack portion. A state (second state) in which paper is being discharged onto the transport path R6 is shown.

  First, in the state shown in FIG. 5A, the image forming apparatus 19 (FIG. 1) transfers the image to the post-processing apparatus 10, passes through the entrance-side conveyance path R1, and drives the guide roller pair R51 to perform the post-processing unit 30. The sheet P discharged to the in-stack conveyance path R6 is guided to the front plate 62 of the urging member 60 set to the sheet receiving attitude standing on the transverse shaft 113, and the inside of the in-stack conveyance path R6. Thus, the lower end edge is supported by the stopper plate 435a of the sheet lifting member 43 set at the sheet receiving position.

  In this state, the belt motor 451 (FIG. 1) is driven, and the sheet elevating member 43 is moved to the lower position indicated by the two-dot chain line in FIG. Is lowered. In synchronization with this, the biasing member 60 set in the paper receiving posture is rotated clockwise around the transverse shaft 113 via the L-shaped projecting piece 64 by the protrusion of the operation rod 651 driven by the actuator 65. The urging posture is set, and the upper edge portion of the paper P is pushed toward the paper receiving plate 42 of the receiving unit 40 as shown in FIG. It is done.

  Next, as shown in FIG. 5C, in the state where the paper urging posture of the urging member 60 is maintained, the paper elevating member 43 is the original paper receiving position indicated by the solid line from the lower position indicated by the two-dot chain line. Is raised towards. With this rise, the sheet P also moves up in the transport path R6 in the stack unit. As the sheet P rises, the upper edge of the sheet P is forward of the lower guide plate 72 by the urging member 60 set in the sheet urging posture (see FIG. 5), the upper edge of the paper P is inclined toward the guide roller pair R51 by a curl rod or the like, and the upper edge of the paper P is the lower guide plate 72. Is inserted between the sheet receiving plate 42 and the attitude maintaining member 70 without going to the guide roller pair R51.

  Then, with the upper end portion of the paper P positioned between the lower guide plate 72 and the paper receiving plate 42, the biasing member 60 is rotated clockwise by a predetermined angle around the transverse shaft 113 to receive the paper. The posture is set to the posture, and in this state, as shown in FIG. 5D, the second sheet P is supplied to the intra-stack conveyance path R6. Therefore, the second sheet P is not inserted in front of the first sheet P.

  Next, the operations shown in (a) to (d) of FIG. 5 are repeated for the second sheet P, and the same operations are repeated for the third and subsequent sheets. The sheet bundle P1 is sequentially formed in a state in which the sheet is prevented.

  Each time the paper P is supplied to the intra-stack conveyance path R6, the paper elevating member 43 reciprocates between an upper position and a lower position in a state where the lower end edge surface of the paper bundle P1 is supported by the stopper plate 435a. Therefore, the sheet bundle P1 is in a so-called aligned state in which the upper and lower edges are aligned.

  When the last paper P is supplied to the intra-stack conveyance path R6, the paper elevating member 43 is rotated by the belt motor 451 (FIG. 2) to turn the endless belt 45 up and down in the counterclockwise direction. Thus, the sheet bundle P1 is directed to the general-purpose tray 15 via the general-purpose tray transport path R4.

  The thus configured post-processing apparatus 10 is provided with a control unit 80 composed of a microcomputer, and the sheet P is discharged to the intra-stack conveyance path R6 of the post-processing unit 30 by the control of the control unit 80. Thus, the alignment of the sheet bundle P1 formed by the above is ensured.

  FIG. 6 is a block diagram for explaining the alignment control of the sheet bundle P1 by the control unit 80. As shown in this figure, the control unit 80 has a basic configuration including a CPU 81 as a central processing unit, a read-only ROM 82 attached to the CPU 81, and a readable / writable RAM 83. The ROM 82 stores a program for executing this control, and the program is read into the CPU 81 every time the post-processing device 10 is powered on. In contrast, the RAM 83 is used for reading and writing temporary data necessary for control.

  The CPU 81 is provided with a sheet acceptance determining unit 811, a sheet biasing instruction unit 812, a sheet bundle lifting / lowering instruction unit 813, and a sheet end determining unit 814. Outside the CPU 81, a counter 84 is provided that counts the number of sheets P discharged to the intra-stack conveyance path R6 in one job.

  The paper receiving determination unit 811 outputs a predetermined signal toward the paper urging instruction unit 812 and the paper bundle raising / lowering instruction unit 813 every time the paper P passes the transport path R5 for the stack unit. For this purpose, a sheet receiving sensor 801 for detecting that the sheet P is directed to the in-stack conveyance path R6 via the guide roller pair R51 is provided at an appropriate position in the vicinity of the guide roller pair R51. The sheet receiving sensor 801 The detection signal is input to the paper acceptance determination unit 811 each time it is detected. Each time this detection signal is input, the paper acceptance determination unit 811 determines that the paper P has been received by the intra-stack conveyance path R6, and this is directed toward the paper urging instruction unit 812 and the paper bundle elevation instruction unit 813. The signal shown is output.

  After obtaining the detection signal from the paper acceptance sensor 801, the paper urging instruction unit 812 displays the two-dot chain line in FIG. 5 (a) after the paper elevating member 43 is lowered from the upper position to the lower position. ) Outputs a control signal for changing the posture of the biasing member 60 set in the paper receiving posture toward the actuator 65 to the paper biasing posture, while the paper elevating member 43 set in the lower position. When the posture is changed to the upper position, a control signal for changing the posture of the biasing member 60 to the original paper receiving posture toward the actuator 65 (see FIG. 5D) is output. .

  In order to perform the operation of the urging member 60, an elevating member position sensor 802 is provided at an appropriate position (in the example shown in FIG. 2, the elevating member position sensor 802 is provided in the vicinity of the belt motor 451, and the belt The height level of the sheet elevating member 43 is obtained by detecting the rotation speed of the motor 451 for use). Then, the detection signal of the elevating member position sensor 802 is once input to the paper receiving determination unit 811, and a signal based on the determination result is output to the paper biasing instruction unit 812, and the paper attachment that has received this signal is attached. The urging instruction unit 812 outputs a control signal for the urging member 60 to change a predetermined posture with respect to the actuator 65.

  The sheet bundle raising / lowering instruction unit 813 outputs a motor drive control signal to the belt motor 451 after the urging member 60 is changed from the sheet receiving attitude to the sheet urging attitude. For this purpose, an urging member attitude sensor 803 is provided in the vicinity of the urging member 60 to detect whether the urging member 60 is in a paper receiving attitude or a paper urging attitude. When the detection signal from the urging member posture sensor 803 that detects that the urging member 60 is set to the paper urging posture is input, the sheet acceptance determining unit 811 receives the sheet bundle up / down instruction unit. A signal indicating that is output to 813.

  The sheet bundle raising / lowering instruction unit 813 outputs a motor drive control signal to the belt motor 451 after the urging member 60 is changed from the sheet receiving attitude to the sheet urging attitude. For this purpose, an urging member attitude sensor 803 is provided in the vicinity of the urging member 60 to detect whether the urging member 60 is in a paper receiving attitude or a paper urging attitude. When the detection signal from the urging member posture sensor 803 that detects that the urging member 60 is set to the paper urging posture is input, the sheet acceptance determining unit 811 receives the sheet bundle up / down instruction unit. A signal indicating that is output to 813.

  Accordingly, upon receiving this signal, the sheet bundle raising / lowering instruction unit 813 outputs a control signal for raising the sheet raising / lowering member 43 by a predetermined distance to the belt motor 451 via the raising / lowering endless belt 45, while the biasing member 60. Is set to the paper receiving posture, so that a control signal for lowering the paper lifting member 43 to the lower position is output to the belt motor 451.

  In the present embodiment, the control unit 80 includes a counter 84. The counter 84 counts the number of sheets each time the sheet receiving sensor 801 detects the sheet P. On the other hand, the image forming apparatus The number of sheets P to be discharged from 19 to the post-processing device 10 is input to the CPU 81, and the sheet acceptance determination unit 811 indicates that the number counted by the counter 84 is the number information from the image forming apparatus 19. At the time of coincidence, a signal for returning the urging member 60 to the initial state ((A) in FIG. 5) is output to the paper urging instruction unit 812, and the paper elevating member 43 is raised to the vicinity of the guide roller pair R51. A signal is output to the sheet bundle up / down instruction unit 813. As a result, the sheet bundle P1 aligned on the intra-stack conveyance path R6 is discharged to the general-purpose tray 15 via the general-purpose tray conveyance path R4. Thereafter, the paper lifting / lowering member 43 is returned to the initial position (indicated by a solid line in FIG. 5A) and is prepared for the paper P of the next job.

  The post-processing apparatus 10 to which the paper stacking mechanism according to the present invention is applied sequentially receives the paper P by the stack unit 20 including the paper receiving plate 42 that receives and temporarily stores the transported paper P. Is configured to align the sheet bundle P1 obtained by the above process on the sheet receiving plate 42.

  The paper stacking mechanism provided in the post-processing device 10 includes a biasing member 60 that biases the rear end of the paper P toward the paper receiving plate 42 each time the paper P is discharged to the stack unit 20. A sheet elevating member 43 provided at the bottom of the stack unit 20 and elevating the sheet bundle P1 between the upper position and the lower position along the sheet receiving plate 42; and the sheet raised to the upper position by the sheet elevating member 43 And a posture maintaining member 70 that guides the rear end of the bundle P1 toward the sheet receiving plate 42, and the next sheet P is discharged to the stack section 20 in a state where the sheet bundle P1 is raised to the upper position. After the paper discharge, the urging member 60 urges the rear end portion of the sheet bundle P1, and the sheet elevating member 43 is configured to descend so as to direct the sheet bundle P1 to the lower position.

  Accordingly, when the sheet bundle P1 rises to the upper position due to the elevation of the sheet elevating member 43, the rear end portion (upper edge portion) of the sheet bundle P1 is guided to the posture maintaining member 70 and guided toward the sheet receiving plate 42, In this state, the next sheet P is discharged to the stack unit 20, and the next sheet P is discharged to the stack unit 20 without interfering with the upper edge portion of the sheet bundle P 1. The page misalignment caused by fitting between the bundles P1 can be reliably prevented.

  Then, after the next sheet P is discharged to the stack unit 20, the urging member 60 urges the rear end (upper end) of the sheet bundle P1, while the sheet elevating member 43 moves the sheet bundle P1 downward. Since the sheet P is lowered as much as possible, the sheet P newly stored in the stack unit 20 is overlapped on the already formed sheet bundle P1 without a gap, so that only the new sheet P is not separated from the sheet bundle P1. A new sheet bundle P1 is formed.

  Further, each time a new sheet P is discharged to the stack unit 20, the sheet bundle P1 is moved up and down between the upper position and the lower position by driving the sheet elevating member 43. It is possible to perform alignment processing in which the end portions of the sheet bundle P1 are aligned by an impact (inertial force) when the sheet lifting member 43 that has been stopped suddenly stops.

  In this way, the sheet elevating member 43 moves up and down in synchronization with the timing of receiving the sheet P, thereby eliminating the page misalignment of the sheet bundle P1 and suppressing the generation of annoying noise because the brush roller is not used. As a result, it is possible to contribute to the reduction of the cost of parts at the time of manufacture and the running cost at the time of use since the expensive brush roller is not used, and to realize the highly accurate alignment processing of the sheet bundle P1. be able to.

  The posture maintaining member 70 also covers the lower guide plate 72 in a state where the guide roller on the paper receiving plate 42 side of the guide roller pair R51 that guides the paper P to the stack unit 20 is covered with the rising paper bundle P1. Therefore, the upper edge portion of the sheet bundle P1 heading upward by driving the sheet elevating member 43 is guided to the lower guide plate 72 covered with the guide roller on the sheet receiving plate 42 side, thereby the sheet bundle P1. Can be reliably sent out toward the general-purpose tray 15 via the transport path R5 for the stack portion.

  In addition, a control unit 80 that controls driving of the urging member 60 and the paper elevating member 43 is provided, and the control unit 80 positions the paper elevating member 43 in the upper position before the paper P is discharged to the stack unit 20. The paper elevating member 43 is once lowered to the lower position while the paper P is urged by the urging member 60 set to the paper receiving posture after the paper P is discharged to the stack unit 20. Subsequently, the paper receiving determination unit 811, the paper biasing instruction unit 812, and the paper bundle are operated so as to perform a series of operations for causing the stacking unit 20 to guide the stacking unit 20 by returning the biasing member 60 to the paper receiving posture. An elevation instruction unit 813 is provided.

  Therefore, based on the control signal from the paper acceptance determination unit 811 via the paper urging instruction unit 812 and the paper bundle up / down instruction unit 813, the paper elevating member 43 has already been formed before the paper P is discharged to the stack unit 20. The urging member 60 that has been set to the sheet receiving posture after the sheet bundle P1 that has been raised is raised to the upper position and the sheet P is discharged to the stacking unit 20 in this state, causes the sheet receiving plate 42 to receive the sheet P. In this state, the paper elevating member 43 is lowered to lower the sheet bundle P1 to the lower position, and the paper is discharged in a state where the urging member 60 is returned to the paper receiving posture. Since the biasing member 60 and the paper elevating member 43 perform a series of operations for guiding the paper P to the stack unit 20, the manual operation is not particularly performed on the paper bundle P1 stored in the stack unit 20. Paper can be automatically aligned sheet bundle P1 formed is discharged to the stack unit 20.

  The present invention is not limited to the above embodiment, and includes the following contents.

  (1) In the above embodiment, the guide roller pair R51 is covered with the attitude maintaining member 70, and the upper end portion of the paper P discharged by the attitude maintaining member 70 is prevented from being bent toward the guide roller pair R51. However, the present invention is not limited to covering the guide roller pair R51 with the control unit 80, but the sheet P or the intra-stack conveyance path bent from the intra-stack conveyance path R6 to the guide roller pair R51 side. The sheet bundle P1 discharged from R6 may be guided by the guide roller on the sheet receiving plate 42 side of the guide roller pair R51. In this way, without providing the posture maintaining member 70 in particular, the upper edge of the sheet bundle P1 that is directed upward by the driving of the sheet elevating member 43 has the peripheral surface facing the sheet bundle P1 toward the sheet receiving plate 42. It is guided to the guide roller on the side of the paper receiving plate 42 rotating in the pushing direction, and can be surely directed to the direction of the paper receiving plate 42. In addition, since it is not necessary to provide the posture maintaining member 70, it is possible to contribute to a reduction in the number of parts, and it is possible to contribute to a reduction in apparatus cost.

  (2) In the above-described embodiment, the post-processing device 10 including the job tray 14 and the half-fold processing unit 16 is employed. However, in the present embodiment, the post-processing device 10 includes the job tray 14 and the middle folding portion. The processing unit 16 is not limited to be provided, and any processing unit 16 may be used as long as at least the stack unit 20 (post-processing unit 30) is provided.

It is explanatory drawing of the side view for demonstrating the internal structure of one Embodiment of the post-processing apparatus which concerns on this invention. It is a schematic side view which shows one Embodiment of a stack part (post-processing unit). It is a perspective view showing one embodiment of a paper raising / lowering member. It is a perspective view showing one embodiment of a biasing member and a posture maintenance member. FIG. 6 is an explanatory diagram for explaining the operation of the sheet bundle alignment process in the post-processing unit in the post-processing apparatus according to the present invention; (A) is a diagram immediately after the first sheet is discharged to the transport path in the stack unit. The state (b) shows a state where the paper discharged into the transport path in the stack part has been lowered by the lowering of the paper elevating member, and (c) shows that the paper once lowered in the transport path in the stack part has moved up the paper elevating member. (D) shows a state in which the next sheet is being discharged to the intra-stack conveyance path. It is a block diagram for explaining alignment control of the sheet bundle P1 by the control unit. It is the schematic of the side view which shows the conventional post-processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Post-processing apparatus 11 Housing | casing 111 Paper inheritance opening 112 Support | pillar 113 Transverse axis 12 Punch part 121 Punch mechanism 13 Paper distribution part 131 Retraction drum 14 Job tray 141 Unit tray 15 General-purpose tray 16 Middle folding processing part 161 Middle folding unit 162 Medium Folding roller pair 163 Push mold 164 Unloading roller pair 165 Pressing member 17 Middle folding tray 19 Image forming apparatus 191 Paper discharge port 20 Stack unit 30 Post-processing unit 40 Receiving unit 41 Side plate 42 Paper receiving plate 43 Paper elevating member 44 Staple mechanism 45 Elevating Endless belt 451 belt motor 452 driving roller 453 driven roller 453a lowest roller 453b roller shaft 50 cover unit 51 side plate 52 cover plate 53 receiving portion 60 biasing member 61 side plate 62 front plate 63 upper plate 64 L-shaped projecting piece 65 Actuator 651 Operating rod 652 Connecting shaft 70 Posture maintaining member 71 Upper guide plate 72 Lower guide plate 80 Control unit 801 Paper receiving sensor 802 Lifting member position sensor 803 Energizing member posture sensor 81 CPU
811 Paper acceptance determining unit 812 Paper urging instruction unit 813 Paper bundle raising / lowering instruction unit 814 Paper end determining unit 82 ROM 83 RAM
84 Counter R Paper transport path R1 Inlet transport path R2 Annular transport path R3 Job tray transport path R4 General purpose tray transport path R5 Stack section transport path R51 Guide roller pair R6 Stack section transport path R7 Middle folding section transport path R8 Unloading Conveyance path P paper (may be stored paper)
P1 paper bundle (storage paper)

Claims (5)

A stack unit having a standing paper receiving plate for temporarily storing the conveyed paper ;
A paper urging member that urges the paper toward the paper receiving plate each time the paper is discharged to the stack unit;
A paper elevating member that is provided in the stack unit and raises and lowers the stored paper between an upper position and a lower position along the paper receiving plate;
A posture maintaining member that maintains the posture of the stored paper along the paper receiving plate side in a state where the stored paper is raised to the upper position by the paper lifting member and the bias by the paper biasing member is released; And
The stored paper is raised to the upper position by the paper lifting member and the posture is maintained by the posture maintaining member, and the next paper is discharged to the stack unit .
After the paper discharge, the paper urging member urges the paper, and the paper elevating member is configured to descend so as to direct the stored paper to a lower position where the posture is not maintained by the posture maintaining member. Characteristic paper stack mechanism.   2. The paper stacking mechanism according to claim 1, wherein the paper urging member presses a rear end portion in the paper discharge direction. A stack unit having a standing paper receiving plate for temporarily storing the conveyed paper;
A paper urging member that urges the paper toward the paper receiving plate each time the paper is discharged to the stack unit;
A paper elevating member that is provided in the stack unit and raises and lowers the stored paper between an upper position and a lower position along the paper receiving plate;
A posture maintaining member that maintains the posture of the stored paper along the paper receiving plate side in a state where the stored paper is raised to the upper position by the paper lifting member and the bias by the paper biasing member is released; And
The position maintaining member is I Oh the guide plate covered state with respect to the sheet bundle coming raised the sheet receiving plate side guide roller of the guide rollers for guiding the sheet to the stack unit,
The next sheet is discharged to the stack portion with the storage sheet raised to the upper position. After the sheet discharge, the sheet urging member urges the sheet while the sheet elevating member lowers the storage sheet. A sheet stacking mechanism configured to move downward toward a position. A stack unit having a standing paper receiving plate for temporarily storing the conveyed paper;
A paper urging member that urges the paper toward the paper receiving plate each time the paper is discharged to the stack unit;
A paper elevating member that is provided in the stack unit and raises and lowers the stored paper between an upper position and a lower position along the paper receiving plate;
A posture maintaining member that maintains the posture of the storage paper along the paper receiving plate side in a state where the storage paper is raised to an upper position by the paper elevating member and the urging by the paper urging member is released;
And a control section for controlling the drive of the paper urging member and the sheet lifting member, is provided,
The controller is
A first state in which the paper elevating member moves from the lower position to the upper position, the paper urging member urges the paper, and the posture maintaining member acts to maintain the posture of the stored paper and prepares for receiving the paper. When,
A second state in which the paper elevating member is located at the upper position, and the paper urging by the paper urging member is released in the state in which the action of the posture maintaining member is continued, and the acceptance of the paper is started;
A third state in which the paper elevating member is moved from the upper position to the lower position, the paper urging by the paper urging member is released in a state where the action of the posture maintaining member is released, and the paper storage operation is performed;
A fourth state in which the paper urging member urges the paper in a state where the paper elevating member is located at the lower position and the release of the action of the posture maintaining member is continued is performed. A paper stack mechanism . 5. A post-processing apparatus employing the paper stack mechanism according to claim 1, wherein the post-processing apparatus is configured to perform predetermined post-processing on a sheet bundle stored and aligned in the stack unit. A post-processing device.

Images