JP6566438B2 - Drilling system - Google Patents

Description

  The present invention relates to a punching system for automatically punching files or other punch holes in various sheet-like workpieces such as paper sheets, plastic sheets, metal sheets, cloth sheets and the like.

  Conventionally, it is mounted on image forming apparatuses such as copiers, printing machines, facsimile machines, post-processing apparatuses, bookbinding apparatuses, etc., and a binding hole for, for example, a file is formed in a sheet such as a paper sheet carried out from these apparatuses. A punching device is used to do this. In recent years, high-speed processing of sheets discharged from an image forming apparatus or the like has progressed, and in response to this, the punching device is also required to increase the speed and efficiency of the punching processing.

  Many perforating apparatuses perforate a sheet conveyed to a predetermined position by reciprocating a punch member in a perforating direction via a cam mechanism by a drive motor. In this case, if the conveyed sheet is punched without stopping, when the punch member is pulled out from the punched hole, the punch is caught on the edge of the punched hole, and the punched hole is damaged or the quality is deteriorated. There is a risk of causing.

  Therefore, a punching device that punches while conveying the punch and the die at the same speed as the sheet is known (see, for example, Patent Document 1). This punching device reciprocates the punch unit and the die unit in the sheet conveying direction by a crank mechanism that can move in the sheet width direction.

  Also, a punching device that punches with a simpler structure and control while conveying the punch and die at the same speed as the sheet has been proposed (for example, see Patent Document 2). This punching device uses a cylindrical cam mounted on a horizontal rotating shaft to reciprocate a punching unit having a punch and a die in the sheet conveying direction, and reciprocates the punch by a bulging cam mounted coaxially with the cylindrical cam. The sheet is perforated by moving it.

JP 2008-173734 A JP 2013-43224 A

  The punching device of Patent Document 1 requires a separate moving mechanism for moving the punch unit and the die unit in the sheet width direction in addition to the crank mechanism for moving the punch unit and the die unit in the sheet conveying direction. For this reason, there is a possibility that the entire apparatus becomes larger, complicated, or requires complicated control, and it is not possible to meet the demands for downsizing and low profile due to recent downsizing of image forming apparatuses and subsequent processing apparatuses. Cause problems.

  The punching device of Patent Document 2 drives the reciprocating motion of the punch and die in the sheet conveying direction and the punching operation of the punch by a cylindrical cam and a bulging cam that rotate integrally on the same axis. It is difficult to perform the punching operation by accurately matching the moving speed of the punch and the die with the conveying speed of the sheet by such a cylindrical cam.

  On the other hand, when punching a moving sheet, the punch is preferably extracted from the punched hole in as short a time as possible. This is because when the cutting edge of the punching blade comes out of the punch hole, it may be damaged by touching the periphery of the punch hole, or the quality of the punch hole may be deteriorated. In particular, when a sheet is conveyed at high speed, there is a high possibility of punch hole damage and quality deterioration by the perforating blade.

  Accordingly, the present invention has been made in view of the above-described problems of the prior art, and its purpose is to convey a sheet while reducing the size and height of the entire apparatus with a relatively simple configuration. Another object of the present invention is to provide a drilling system that can punch holes with high quality.

In order to achieve the above object, the drilling system of the present invention provides
A punching member having a punching blade at one end in the axial direction, reciprocating in the axial direction, and punching holes in the sheet conveyed in a predetermined conveying direction, and the punching holes are formed in the sheet by the punching member. A punching device having a sheet clamping portion that clamps the sheet from both sides thereof,
The punching device is provided so as to be movable along a predetermined conveying direction.

  With this configuration, when punching a sheet with the punch member, the punching device includes a force that the outer peripheral surface of the punch member receives in the predetermined conveying direction from the periphery of the punch hole that engages with the punch member, A frictional force generated between the sheet surface and the sheet surface acts. These forces acting from the conveyed sheet allow the punching device to punch holes while moving at the same speed as the sheet without using separate drive means or control means.

  At this time, the reaction force that the punch hole periphery receives from the outer peripheral surface of the punch member is smaller than the force necessary to move the punching device integrally with the sheet by the friction force between the sheet clamping portion and the sheet surface. That's it. Therefore, it is possible to eliminate or greatly reduce the possibility that the punch hole periphery is damaged by the engagement with the outer peripheral surface of the punch member during drilling.

  Furthermore, the sheet is clamped by the sheet clamping unit, so that the position of the sheet in the axial direction can be always fixed and maintained until the punch member is punched and removed from the punch hole. Accordingly, since the punch member can be removed from the punch hole in a shorter time, the possibility that the edge of the punching blade touches the peripheral edge of the punch hole and is damaged at that time, or the quality of the punch hole is deteriorated is eliminated or greatly reduced. To reduce.

  Thus, according to the present invention, it is possible to punch holes in the sheet while moving the punching apparatus at the same speed as the sheet integrally without providing separate driving means and control means. Since the force necessary to move the apparatus is distributed and applied to a wide part of the sheet, the sheet is not damaged. Therefore, high-quality and high-quality punch holes can be formed.

  In one embodiment, the sheet clamping unit includes a sheet support surface that supports the sheet at a punching position where a punch hole is formed in the sheet by the punch member, and a pressing member that presses the sheet against the sheet support surface. Thereby, the pressing force applied to the sheet from the pressing member can generate a frictional force necessary to share the force for moving the punching device between the sheet supporting surface and the pressing member and each surface of the sheet. it can. Further, in many cases, this type of punching device is provided with a sheet support surface for supporting the sheet at the punching position. By using this as a sheet clamping portion, the number of parts can be reduced and the entire device can be reduced. The structure can be simplified.

  In another embodiment, the pressing member includes a pressing surface that abuts against a surface of the sheet that is opposite to the sheet support surface, and includes a spring member that biases the pressing surface toward the sheet. By using the spring member, the necessary pressing force against the sheet can be obtained relatively easily, and the configuration of the entire apparatus can be further simplified.

  In yet another embodiment, the urging force of the spring member changes according to the amount of movement of the punch member in the axial direction, so that the necessary pressing force on the sheet can be obtained in accordance with the progress of the punching operation by the punch member. it can. Further, before the punching operation is started, the spring member can be adjusted so as not to delay or prevent the conveyance of the sheet.

  In one embodiment, the spring member comprises a leaf spring member bent into two spring plate portions, and one surface of one spring plate portion forms a pressing surface. Thereby, the function of the urging force that exerts the necessary pressing force and the pressing surface can be realized by one member, the number of parts can be reduced, the configuration of the entire apparatus can be simplified, and the size can be reduced.

  In another embodiment, the distance between one spring plate portion and the other spring plate portion of the leaf spring member is changed in accordance with the amount of movement of the punch member in the axial direction, thereby having a very simple structure. The required pressing force corresponding to the progress of the punching operation by the punch member can be obtained.

  In still another embodiment, the other spring plate portion is displaced in the axial direction together with the punch member, whereby the urging force of the plate spring member can be changed corresponding to the progress of the punching operation by the punch member.

  In one embodiment, the punching device is further provided with biasing means for biasing the punching device in the direction opposite to the predetermined conveying direction, so that the punching device can be quickly moved to the original punching start position in preparation for the next drilling operation. Can be automatically restored.

  According to another aspect of the present invention, there is provided a sheet processing apparatus provided with the above-described perforating system of the present invention, thereby enabling punch holes to be punched with high quality while conveying a sheet.

  Further, according to another aspect of the present invention, the punching system of the present invention described above or the sheet processing apparatus of the present invention described above is provided, so that the punch hole is formed with high quality while conveying the sheet after image formation. An image forming apparatus that can be perforated is provided.

1 is a plan view showing an embodiment of a drilling system according to the present invention. FIG. 2 is a side view of the drilling system of FIG. 1. The front view of a punching apparatus. The side view of a punching apparatus. The top view of a punching device. The longitudinal cross-sectional view which shows the perforation part of a perforation apparatus. The perspective view which shows a sheet | seat press part and a perforation part. The side view of the perforation apparatus in which a punch member exists in a top dead center position. The side view of the punching apparatus in which the blade edge | tip of a punch member exists in the upper end position of a sheet | seat path | route. The side view of the punching apparatus in which a punch member blade edge exists in the lower end position of a sheet path. The side view of the punching apparatus in which a punch member is in a bottom dead center position.

DESCRIPTION OF EMBODIMENTS Hereinafter, a drilling system of the present invention will be described in detail based on an embodiment thereof with reference to the accompanying drawings.
The punching system of this embodiment is incorporated in a main body device such as an image forming apparatus or a post-processing device, for example, and forms a binding hole for a file while conveying a sheet such as a paper sheet carried from the image forming apparatus. It is used to do.

  1 and 2 show the overall configuration of a drilling system 100 according to a preferred embodiment of the present invention. The punching system 100 includes a punching device 1, a frame 2 to which the punching device is attached, and a sheet transport mechanism 101 that transports the sheet S. The sheet conveying mechanism 101 extends from the upstream side to the downstream side of the punching device 1 along the sheet conveying direction A, and has an upper guide plate 102 and a lower guide plate 103 that are arranged to face each other. Between the upper guide plate and the lower guide plate, a guide path 104 for the sheet S having a certain slight gap is defined.

  On the upper and lower guide plates 102, 103, a pair of upper and lower carry rollers 105, 106 are arranged symmetrically with respect to the sheet conveyance direction A on the upstream side immediately in the sheet conveyance direction A of the punching device 1. Yes. Further, four pairs of upper and lower pair of carry-out rollers 107 and 108 are arranged symmetrically on the downstream side of the punching device 1 in the sheet conveying direction A. In particular, the pair of carry-out rollers 107 a and 108 a disposed at the end on the side of the punching device 1 are disposed at corresponding positions in the left-right direction on the downstream side of the punching position of the punching device 1.

  Each of the carry-in roller pairs is rotatably supported by carry-in roller shafts 109 and 110 that traverse the upper and lower guide plates 102 and 103 in the left-right direction. Similarly, each of the carry-out roller pairs is rotatably supported by carry-out roller shafts 111 and 112 that traverse the upper and lower guide plates 102 and 103 in the left-right direction.

  The upper carry-in roller shaft 109 and the carry-out roller shaft 111 are urged at a predetermined pressure toward the lower carry-in roller shaft 110 and the carry-out roller shaft 112 by coil springs 113 and 114, respectively. Accordingly, the outer peripheral surfaces of the upper carry-in roller 105 and the carry-out roller 107 press the corresponding outer peripheral surfaces of the lower carry-in roller 106 and the carry-out roller 108 with the predetermined pressure, respectively. By this pressing force, each of the carry-in and carry-out rollers sandwiches the sheet S in the guide path 104 from above and below through windows opened on the upper and lower guide plates 102 and 103, respectively. It conveys in the conveyance direction A by rotation.

  The lower carry-in roller shaft 110 and the carry-out roller shaft 112 are connected to each other at their opposite ends 110 a and 112 a by a belt transmission mechanism including pulleys 115 and 116 and a belt 117. Similarly, the opposite end 110b of the carry-in roller shaft 110 is connected to an output shaft (not shown) of the drive motor 120 by a belt transmission mechanism including a pulley 118 and a belt 119. Accordingly, when the drive motor is rotated, the lower carry-in roller shaft 110 and the carry-out roller shaft 112 are rotationally driven in the sheet conveyance direction, and the upper carry-in roller pressed against the lower carry-in roller 106 and the carry-out roller 108. Similarly, 105 and the carry-out roller 107 rotate in the sheet conveyance direction.

  The punching device 1 is fixed to the frame 2 using an attachment unit 3. The attachment unit 3 has a lower support member 4 fixed to the frame 2 and an upper movable attachment member 5 movable with respect to the support member. The movable attachment member 5 can move linearly in both directions along the sheet conveying direction within a predetermined movement range defined by guide rod means (not shown) provided on the support member 4.

  3 to 6 show the entire configuration of the perforation apparatus 1. The punching device 1 includes a punching unit 11, a drive unit 12, and a frame structure 13. The frame structure 13 includes a lower frame 14 for guiding a sheet to be punched and for mounting the punching device 1 to the mounting unit 3, and an upper frame 15 for assembling the punching unit 11 and the drive unit 12. The

  A pin 121 protrudes from the frame 2 immediately upstream in the sheet conveying direction of the punching device 1. A tension coil spring 122 is interposed between the punching device 1 and the frame 2 with each end engaged with the upper frame 15 and the pin 121. The punching device 1 is always urged upstream by the tension coil spring 122 toward the home position at the upstream end of the moving range.

  As shown in FIGS. 3 and 4, the lower frame 14 is formed of a substantially rectangular flat plate member, and the upper surface thereof is a horizontal and flat sheet support surface 14a for supporting the sheet S that is a work piece to be punched. Is defined. The upper frame 15 has a lower plate 16 disposed so as to face the seat support surface 14a with a certain slight gap. A slight gap between the sheet support surface 14a and the lower plate 16 defines a sheet path 17 for allowing the sheet S to pass through the punching position. The lower frame 14 and the lower plate 16 of the upper frame 15 are integrally coupled with the spacer plate at the end opposite to the seat passage 17.

  The sheet support surface 14 a is disposed so as to be flush with the upper surface of the lower guide plate 103 of the sheet conveying mechanism 101. The sheet path 17 is set to have substantially the same dimensions as the guide path 104 of the sheet conveying mechanism 101. Thereby, the sheet conveyed through the guide path 104 can pass smoothly on the sheet support surface 14a of the punching device 1.

  As shown in FIGS. 3 and 5, the upper frame 15 is provided with the perforated portion 11 on the seat passage 17 side and the drive portion 12 on the opposite side. The upper frame 15 is bent vertically upward from the end of the lower plate 16 opposite to the drive portion 12 and vertically upward from the upstream end of the lower plate 16. It further includes a side plate 19 and an upper plate 20 that is bent inwardly in parallel with the lower plate 16 at the upper end of the side plate 19, that is, horizontally to form a U-shape as a whole.

  As shown in FIG. 6, the perforated portion 11 includes a circular rod-shaped punch member 21 that extends in the vertical direction and has a substantially constant diameter over the entire length. The punch member 21 has a cylindrical punching blade 22 formed at the lower end thereof. The perforating blade 22 is formed so as to cut out the cylindrical peripheral edge of the punch member 21 in a V shape when viewed from the side, that is, to define a V-shaped notch at a certain facing side surface position of the cylindrical peripheral edge. Is formed. The punch member 21 has two diametrical through-holes 23 and 24 formed in the upper and lower portions, and a relatively narrow circumferential groove 25 is provided around the entire circumference in the vicinity of the center in the axial direction. Yes.

  Circular through holes 26 and 27 are formed in the lower plate 16 and the upper plate 20 of the upper frame 15 at positions corresponding to the vertical direction, respectively. An upper end portion of the punch member 21 is inserted into the upper through hole 27 and a lower end portion thereof is inserted into the lower through hole 26 so as to be rotatable and slidable in the axial direction. A circular die hole 28 for punching the sheet S by the punching blade 22 is provided in the lower frame 14 at a position corresponding to the through hole 26 of the lower plate 16 in the vertical direction.

  The punch member 21 is externally provided with a cam member 31 formed of a cylindrical cam concentrically therewith. The cam member 31 can be composed of a substantially cylindrical upper cam half 31a and a lower cam half 31b. The upper cam half body 31a and the lower cam half body 31b are assembled so as to be able to rotate integrally in the circumferential direction by fitting each other vertically.

  An upper cam surface 32a is formed on the lower surface of the upper cam half 31a so as to be continuous over the entire circumference along the outer peripheral edge thereof. A lower cam surface 32b is formed on the upper surface of the lower cam half 31b so as to be continuous over the entire circumference along the outer peripheral edge thereof. By integrating the two cam halves 31a and 31b as described above, an endless cam groove 33 is formed on the outer peripheral surface of the cam member 31 in the circumferential direction as will be described later.

  On the side plate 18, cam pins 34 project horizontally toward the outer peripheral surface of the cam member 31. The cam pin 34 is disposed so as to fit into the cam groove 33 and engage with the upper cam surface 32a and / or the lower cam surface 32b.

  On the lower surface of the cam member 31 (lower cam half 31b), a narrow groove 35 having a predetermined depth extending in the diameter direction from the periphery of the shaft hole through which the punch member 21 is inserted is formed. On the upper surface of the cam member 31 (upper cam half 31a), a step 36 having a predetermined width and depth is provided along the periphery of the shaft hole through which the punch member is inserted.

  The narrow groove 35 on the lower surface of the cam member 31 is fitted with both end portions of the connecting pin 37 inserted through the lower through hole 24 of the punch member 21 and projecting from both ends of the through hole. For example, a rubber ring 38 is fitted into the step 36 on the upper surface of the cam member 31, and an E ring 39 is fitted into the circumferential groove 25 of the punch member 21 immediately above. Accordingly, the cam member 31 is integrally attached to the punch member 21 in the axial direction and the circumferential direction.

  A sensor flag member 41 is integrally fixed to the upper surface of the cam member 31 as a position detecting member for a position sensor described later. The sensor flag member 41 is formed of a fan-shaped light shielding plate having a fixed width and extending horizontally outward in the radial direction around the axis of the punch member 21.

  A driven gear 42 is concentrically mounted on the punch member 21 at an upper end portion protruding upward from the through hole 27 of the upper plate 20. As will be described later, the driven gear 42 is a worm wheel or a helical gear that meshes with a worm or screw gear on the driving side. The driven gear 42 is formed with a narrow groove 43 extending in the diametrical direction from the periphery of the shaft hole through which the punch member 21 is inserted.

  The narrow groove 35 on the lower surface of the cam member 31 is fitted with both end portions of the connecting pin 44 inserted through the upper through hole 23 of the punch member 21 and projecting from both ends of the through hole. The both end portions of the connecting pin 44 are disposed in the narrow groove 35 so as not to move in the rotational direction of the cam member 31 and to be slidable in the axial direction of the cam member. Further, the driven gear 42 is supported with its lower surface in sliding contact with the upper surface of the upper plate 19. Thus, the driven gear 42 is held so as to be integrally rotatable in the circumferential direction with respect to the punch member 21 and relatively movable in the axial direction.

  As shown in FIG. 4, the upper frame 15 is provided with a sheet pressing portion 70 for pressing the sheet S in the sheet passage 17 against the sheet support surface 14 a on the upstream side in the sheet conveying direction of the punching portion 11. . The sheet pressing portion 70 includes a leaf spring member 71 obtained by bending a thin metal plate made of a spring material such as spring steel into a V shape. The leaf spring member 71 has the bent portion 74 in the seat with the upper surface of the upper spring plate portion 72 facing the lower surface of the cam member 31 and the lower surface of the lower spring plate portion 73 facing the seat support surface 14a. It arrange | positions toward the upstream of a conveyance direction.

  The sheet pressing portion 70 further includes a swing arm 75 for supporting the leaf spring member 71 and a fixture 76 fixed to the side plate 19 of the upper frame 15. The swing arm 75 protrudes laterally from both side edges of the upper spring plate portion 72, and a plate portion extending beyond the bent portion toward the bent portion 74 along the both side edges is bent at a right angle upward. And is pivotally supported by the fixture at the end on the bent portion side so as to swing up and down. Accordingly, the leaf spring member 71 is supported on the side plate 19 of the upper frame 15 so as to be swingable up and down between the cam member 31 and the seat support surface 14a.

  As shown in FIG. 7, the upper spring plate portion 72 has a distal end bent slightly downward to form a cam receiving portion 77 for contacting the lower surface of the cam member 31. The lower spring plate portion 73 is bent slightly upward from the vicinity of the middle portion thereof to form a sheet presser 78 for pressing the sheet S in the sheet passage 17 against the sheet support surface 14a.

  The sheet presser 78 is formed in a Y shape whose front end opens toward the downstream side, and the punch member 21 can penetrate through the opening 78a without contacting the periphery of the opening up and down. Yes. The sheet presser 78 abuts on a sheet portion formed by or formed around the punch hole by the punch member 21. The front end of the sheet presser 78 is bent slightly upward so as to come into contact with the upper surface of the sheet without being caught.

  When the cam receiving portion 77 is pushed down to the lower surface of the cam member 31 and the distance between the upper spring plate portion 72 and the lower spring plate portion 73 is reduced, the plate spring member 71 exerts a biasing force, and the sheet presser 78 is The sheet S is pressed against the sheet support surface 14a. The pressing force applied from the sheet presser 78 to the upper surface of the sheet S increases or decreases depending on the displacement amount of the leaf spring member 71 caused by the cam receiving portion 77 being pushed down to the lower surface of the cam member 31, that is, the axial displacement amount of the lower surface of the cam member. To do.

  The drive unit 12 includes a drive motor 48 for rotating the punch member 21. The upper frame 15 has a side plate 46 disposed opposite to the side plate 18 on the opposite side of the perforated portion 11. The drive motor 48 is mounted horizontally on the side plate 46 with its output shaft 49 protruding horizontally toward the perforated portion 11.

  A driving gear 50 is attached to the tip of the output shaft 49. The driving gear 50 meshes with an intermediate gear 52 that is rotatably mounted on a horizontal rotating rod 51 that is rotatably supported between the side plate 20 and the side plate 18. A worm 53 is formed on the rotating rod 51 and meshes with the driven gear 42. Thereby, the rotation of the drive motor 48 can be transmitted to the punch member 21, and the punch member can be decelerated and rotated.

  In order to detect the rotation amount of the drive motor 48, for example, an optical transmission type encoder 55 is provided on the side opposite to the perforated portion 11. Thereby, the rotation of the drive motor 48 can be controlled with higher accuracy in relation to the position of the sheet S with respect to the punching device 1, for example.

  In the upper frame 15, a position sensor 60 for detecting the rotational position of the punch member 21 is attached to the extension portion 47 of the side plate 46 on the side opposite to the rotating rod 51. The position sensor 60 is a transmissive photosensor, and includes a rectangular box-shaped light projecting unit 62 and a light receiving unit 63 that project toward the punch member 21. The light projecting unit 62 and the light receiving unit 63 are arranged so as to face each other with a predetermined gap therebetween so that the sensor flag member 41 that rotates horizontally can pass through the gap. The position sensor 60 is turned off when light passes from the light projecting unit 62 to the light receiving unit 63, and is turned on when light is blocked by the sensor flag member 41.

  The position sensor 60 is not limited to the transmissive photosensor of the present embodiment described above. If a detector that rotates integrally with the punch member 21 such as the sensor flag member 41 is used, various known sensors such as a reflective photosensor, a magnetic sensor, and an ultrasonic sensor may be used. it can.

  Next, a series of operations for punching the sheet S moving in the guide path 104 at a predetermined conveyance speed by the punching system 100 of the present embodiment will be described with reference to FIGS. In FIG. 8, the punching device 1 is located at the home position on the most upstream side in the movement range. The punch member 21 and the cam member 31 are at the top dead center position that is the uppermost position in the axial direction, and the punching blade 22 stands by in the through hole 26 of the lower plate 16.

  In this standby state, the sheet pressing portion 70 is provided with a small gap between the cam receiving portion 77 and the lower surface of the cam 31 with the sheet presser 78 in contact with the upper surface of the sheet S. Due to this gap, only a part of the weight of the leaf spring member 71 is applied to the upper surface of the sheet S, and the urging force does not act at all. Therefore, the sheet S can be transported through the sheet path 17 at a predetermined speed without being substantially disturbed by the contact with the sheet presser 77.

  In this standby state, when the leading edge of the sheet S reaches a preset punching start position, the punching device 1 starts a punching operation. In the present embodiment, the punching start position is a pressure contact position where the outer peripheral surfaces of the carry-out rollers 107 and 108 are in pressure contact with each other. When the leading edge of the sheet S reaches the pressure contact position, a sensor (not shown) detects this, activates the drive motor 48, and rotates the punch member 21 counterclockwise in the top view of FIG. According to the profile of the cam groove 33, the punch member 21 and the cam member 31 descend along the axial direction from the top dead center position while rotating.

  FIG. 9 shows a state where the punch member 21 and the cam member 31 are lowered to the position where the tip of the punching blade 22 reaches the lower end opening of the through hole 26, that is, the upper end of the sheet passage 17. In the plate spring member 71, the cam receiving portion 77 of the upper spring plate portion 72 is slightly pushed down from the uppermost position in the standby state described above by the lower surface of the cam member 31. At this time, the punching device 1 is still held at the home position, and the sheet S continues to move in the sheet path 17 in the conveyance direction A at a predetermined conveyance speed. At this time, the pressing force acting on the sheet S from the sheet presser 78 is large enough not to substantially delay or prevent the movement of the sheet because the displacement amount of the leaf spring member 71 is small.

  FIG. 10 shows a state in which the punch member 21 and the cam member 31 are further lowered, and the tip of the punching blade 22 reaches the lower end position of the sheet passage 17, that is, the upper surface of the sheet S. From this state, actual punching of the sheet S starts. The sheet S is pressed against the sheet support surface 14 a with a relatively large pressing force by the sheet press 78 when the cam receiving portion 77 is further pushed down from the position of FIG. 9 by the cam member 31. At this time, a frictional force due to the pressing force is generated between the sheet presser 78 and the sheet support surface 14a and the upper and lower surfaces of the sheet S.

  Further, the sheet S immediately before punching is not displaced up and down in the sheet path 17 by being pressed against the sheet support surface 14 a in this way. That is, since the position of the sheet with respect to the axial direction is always fixed and maintained, punching can always be started at the same punch hole formation position of the sheet.

  When the punching blade 22 starts to punch the sheet S, the peripheral surface of the upstream side of the punch member 21 is engaged with the peripheral edge of the punch hole just punched, and the punch member is moved downstream from the peripheral edge of the punch hole. An acting force is generated in the pushing direction. At substantially the same time, the frictional force generated between each surface of the sheet S and the sheet presser 78 and the sheet support surface 14a acts to pull the punching device 1 in the sheet conveying direction A.

  With these forces acting from the sheet S, the punching device 1 punches a punch hole while moving downstream at the same speed as the sheet against the urging force of the tension coil spring 122. At this time, the force necessary to move the punching device integrally with the sheet is that the area near the punch hole of the sheet S that is held between the sheet support surface 14a by the contact of the sheet presser 78 and the peripheral edge of the punch hole. And share. In particular, since the reaction force received by the punch hole periphery from the outer peripheral surface of the punch member can be reduced by the frictional force, the possibility of damage to the punch hole periphery is eliminated or greatly reduced. Further, since the punching device 1 does not require separate driving means and control means for moving together with the sheet S, it is easy to reduce the size.

  FIG. 11 shows a state in which the punch member 21 and the cam member 31 are lowered to the bottom dead center position, the punching blade 22 enters the die hole 28 to the lowest position, and a punch hole is formed in the sheet S. . At this time, the pressing force applied to the sheet S from the leaf spring member 71, and hence the frictional force between the sheet S and the sheet pressing member 78 and the sheet supporting surface 14a is maximized.

  Thereafter, the punch member 21 starts to return from the punch hole and return to the standby position in the through hole 24 of the lower plate 16. Until the punch member 21 is completely removed from the punch hole, the punching device 1 is configured to apply the acting force from the punch hole periphery to the punch member outer peripheral surface, and between the sheet pressing and sheet support surfaces and the sheets S. The frictional force keeps moving together with the sheet S.

  As the drive motor 48 continues to rotate, the punch member 21 rises in the axial direction from the bottom dead center position while rotating. When the punch member 21 reaches the top dead center position, the punch member 21 enters a standby state in preparation for the next drilling operation. The relationship between the punch member 21 and the cam member 31 and the leaf spring member 71 until the top dead center position is reached in the return operation is the reverse order of the drilling operation described with reference to FIGS. Proceed with

  The sheet S is similar to the punching process by the leaf spring member 71 from the bottom dead center position until at least the tip of the hole blade 22 reaches the lower end position of the sheet passage 17 from the bottom dead center position, that is, the upper surface of the sheet S. The sheet is pressed against the sheet support surface 14a with a sufficient pressing force. Thereby, the frictional force required to move the punching device 1 between the sheet presser and the sheet support surface can be generated.

  Further, since the sheet S is maintained on the sheet support surface 14a, the punch member 21 can be detached from the punch hole in a very short time. Therefore, even when the sheet S is conveyed at a high speed, the possibility that the edge of the punching blade 22 touches the periphery of the punching edge 22 when it comes out of the punched hole or deteriorates the quality of the punched hole is eliminated or greatly reduced. The

  When the punch member 21 is detached from the punch hole and the engagement between the outer peripheral surface and the punch hole periphery is released, the punching device 1 quickly moves horizontally by the urging force of the tension coil spring 122, and It returns to the home position and enters a state ready for the next drilling operation. Since the time for the punch member 21 to leave the punch hole is very short, the punching device can be automatically returned to the home position more quickly.

  On the other hand, the sheet S continues to move along the sheet conveyance direction A at a predetermined conveyance speed. The pressing force from the leaf spring member 71 decreases as the punch member 21 and the cam member 31 are raised, and even if the sheet presser 78 is in contact with the upper surface of the sheet after the punch member 21 is detached from the punch hole, The conveyance of the sheet S is not delayed or hindered.

  The size, change, or ratio of the pressing force applied to the sheet S by the leaf spring member 71, the timing of applying the pressing force, the friction coefficient of the sheet pressing 78 and / or the sheet support surface 14a, and the like can be set variously. . For example, the sheet S can be set not to be pressed until the tip of the punching blade 22 reaches the lower end position of the sheet passage 17. Further, in the present embodiment, the pressing force continuously changes according to the descending amounts of the punch member 21 and the cam member 31, but can be changed stepwise.

  Moreover, in the said embodiment, it comprised so that the front-end | tip of the upper side spring board part 72 of the leaf | plate spring member 71 might be contact | abutted to the lower surface of the cam member 31, and the urging | biasing force which presses the sheet | seat S might be exhibited according to the movement amount. In another embodiment, the upper spring plate portion 72 may be pushed down by a separate member or structure that moves in the axial direction directly by the punch member 21 or integrally with the punch member.

  In another embodiment, pressing means other than the leaf spring member can be used to hold the sheet S between the sheet support surface 14a. For example, the pressing surface disposed above the sheet support surface 14a can be pressed against the sheet surface by a spring means other than a leaf spring, various known urging means, or driving means. Further, instead of the sheet support surface 14a, a sheet can be sandwiched between separate members, for example, the lower surface of the lower plate of the upper frame and appropriate pressing means.

  As mentioned above, although this invention was demonstrated in relation to preferred embodiment, this invention is not limited to the said embodiment, In the technical scope, it can implement by adding various change or deformation | transformation. Needless to say. For example, as long as the punching apparatus includes a punch member that reciprocates in the vertical direction with respect to a horizontally conveyed sheet, various configurations other than the above-described embodiment can be applied.

DESCRIPTION OF SYMBOLS 1 punching apparatus 2 frame 3 mounting unit 4 support member 5 movable mounting member 11 punching part 12 drive part 13 frame structure 14 lower frame 14a sheet support surface 15 upper frame 16 lower plate 17 sheet path 18, 20 side plate 19 upper plate 21 Punch member 22 Drilling blade 22a Bottom top portion 28 Die hole 31 Cam member 33 Cam groove 34 Cam pin 41 Sensor flag member 42 Driven gear 48 Drive motor 50 Drive gear 53 Warm 55 Encoder 60 Position sensor 70 Sheet pressing portion 71 Leaf spring member 75 Shaking Moving arm 77 Cam receiving portion 78 Sheet presser 100 Punching system 101 Sheet conveying mechanism 102 Upper guide plate 103 Lower guide plate 104 Guide paths 105, 106 Carry-in rollers 107, 108 Carry-out rollers

Claims (9)

A punch member having a punching blade at one end in the axial direction, reciprocating in the axial direction, and punching holes in a sheet conveyed in a predetermined conveying direction;
When a punch hole is drilled in the sheet by the punch member, a sheet clamping unit that clamps the sheet from both sides;
Comprising a drilling device having
The punching device is provided movably along the predetermined conveying direction ;
The punching system further comprising biasing means for biasing the punching device in a direction opposite to the predetermined transport direction .   The sheet holding portion includes a sheet support surface that supports the sheet at a punching position where a punch hole is formed in the sheet by the punch member, and a pressing member that presses the sheet against the sheet support surface. Item 2. The drilling system according to Item 1.   The said pressing member has a pressing surface which contact | abuts the surface on the opposite side to the said sheet support surface of the said sheet | seat, and consists of a spring member which urges | biases the said pressing surface toward the said sheet | seat. Drilling system.   The piercing system according to claim 3, wherein the biasing force of the spring member changes according to the amount of movement of the punch member in the axial direction.   The perforation system according to claim 3 or 4, wherein the spring member is composed of a leaf spring member bent into two spring plate portions, and one surface of one of the spring plate portions forms the pressing surface.   The punching system according to claim 5, wherein a distance between the one spring plate portion of the leaf spring member and the other spring plate portion changes in accordance with an amount of movement of the punch member in the axial direction.   The drilling system according to claim 6, wherein the other spring plate portion is displaced in the axial direction together with the punch member. It comprises a drilling system according to any one of claims 1 to 7, the sheet processing apparatus. Comprising a sheet processing apparatus according to the drilling system or claim 8 as claimed in any one of claims 1 to 7, the image forming apparatus.

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