JP2007076830A - Folding mechanism, sheet folding device provided with folding mechanism, sheet post-processing device, image forming device, and sheet folding method for folding mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a folding mechanism capable of realizing energy saving, low cost, and high quality by the minimum driving force and to provide a sheet folding device provided with the folding mechanism, a sheet post-processing device, an image forming device, and a sheet folding method for the folding mechanism. <P>SOLUTION: This folding mechanism for folding a sheet is provided with a folding plate 74 movable substantially in the vertical direction in a sheet conveyance passage, a pair of folding rollers 81 exposed in the sheet conveyance passage, and a driving motor for driving the pair of folding rollers 81 to bring a rotation angle of the driving motor and amount of advance, retraction, and travel of the folding plate 74 into proportional relationship. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and the like, and a sheet post-processing apparatus that performs sorting, stacking, binding, saddle stitching, and the like of transfer paper discharged from the apparatus, or in particular, a folding mechanism, and The present invention relates to a sheet folding apparatus, a sheet post-processing apparatus, an image forming apparatus, and a sheet folding method of the folding mechanism that include the mechanism.

  Post-processing devices such as copying machines and printers that are arranged downstream of an image output device and are bound to output recording paper are widely known. In addition, it has been devised that saddle stitching is also possible, and in recent years, the need for energy saving, low cost, and high quality is desired.

  Conventionally, in this type of sheet post-processing apparatus, as a folding method of saddle stitch binding, the center is bound, conveyed while passing through a pair of folding rollers exposed in the sheet conveyance path, and positioned and retained at the folding position. A sheet bundle is half-folded by extruding a binding portion of the sheet bundle in a substantially vertical direction by a folding plate and passing a pair of folding rollers provided in the moving direction.

  It is well known that a force of several hundred N is required to push the sheet bundle up to the folding roller nip with high pressure (about 200 to 400 N) by the folding plate. Therefore, conventionally, a cam mechanism using a crank mechanism or a eccentric shaft is used as disclosed in Patent Documents 1 to 3.

As a method for reducing the pushing force, the folding roller is rotated at a faster peripheral speed than the folding plate and the sheet is pulled in and pushed in with the folding plate, or the one-way clutch is arranged in the folding roller drive system to make it easy to enter the nip. There are ways to reduce the force.
JP 2000-143088 A JP 2001-002317 A Japanese Patent No. 3623573

  However, the above-described method of rotating the folding roller at a peripheral speed faster than that of the folding plate and pushing the sheet while pulling the sheet with the folding plate has problems such as tearing of the cover and wrinkles. Further, the method using the one-way clutch has a problem that it is not suitable for reinforcing the folding line by rotating the folding roller forward and backward, and it becomes an expensive mechanism because of high torque specifications.

  In view of the above problems, the present invention employs a mechanism in which the rotation angle of the drive motor and the forward / backward movement amount of the folding plate are in a proportional relationship, thereby minimizing energy consumption, low cost, and high cost. It is an object of the present invention to provide a quality folding mechanism, and a sheet folding apparatus, a sheet post-processing apparatus, an image forming apparatus, and a sheet folding method of the folding mechanism, which include the mechanism.

  According to a first aspect of the present invention, there is provided a folding plate that is movable in a direction substantially perpendicular to the sheet conveyance path, a pair of folding rollers exposed to the sheet conveyance path, and a drive motor that drives the pair of folding rollers. A folding mechanism for folding the sheet is characterized in that the rotation angle of the drive motor and the amount of forward / backward movement of the folding plate are proportional to each other.

  The invention according to claim 2 is the folding mechanism according to claim 1, wherein a screw mechanism is used to drive the folding plate.

  The invention according to claim 3 is characterized in that the screw mechanism is a ball screw, and is a folding mechanism according to claim 2.

  According to a fourth aspect of the present invention, there is provided a folding mechanism according to the first aspect in which a spiral cam mechanism is used for driving the folding plate.

  The invention according to claim 5 further includes a folding plate guide rod for guiding the folding plate, and has a curvature similar to the curvature of the cam groove in the engagement between the spiral cam groove and the folding plate guide rod. 5. The folding mechanism according to claim 4, wherein a sloping ball-shaped guide member is used.

  A sixth aspect of the invention is a sheet folding apparatus having the folding mechanism according to any one of the first to fifth aspects.

  The invention described in claim 7 is a sheet post-processing apparatus having the folding mechanism according to any one of claims 1 to 5.

  According to an eighth aspect of the present invention, an image forming apparatus having the folding mechanism according to any one of the first to fifth aspects is provided.

  According to a ninth aspect of the invention, there is provided a folding plate that is movable in a direction substantially perpendicular to the sheet conveyance path, a pair of folding rollers exposed to the sheet conveyance path, and a drive motor that drives the pair of folding rollers. In addition, the sheet folding method of the folding mechanism for folding the sheet is characterized in that the sheet folding method of the folding mechanism has a proportional relationship between the rotation angle of the drive motor and the amount of forward / backward movement of the folding plate.

  According to the present invention, by adopting a mechanism in which the rotation angle of the drive motor and the amount of forward and backward movement of the folding plate are in a proportional relationship, an energy saving, low cost, high quality folding mechanism with minimal driving force, and A sheet folding apparatus, a sheet post-processing apparatus, an image forming apparatus, and a sheet folding method of the folding mechanism that include the mechanism can be realized.

  The best mode for carrying out the present invention is a folding mechanism for folding a sheet, a folding plate movable in a direction substantially perpendicular to the sheet conveying path, a pair of folding rollers exposed to the sheet conveying path, and the pair And a folding mechanism in which the rotation angle of the driving motor and the amount of forward / backward movement of the folding plate are proportional to each other.

  Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise described, the present invention is not limited to these embodiments.

(Embodiment 1)
As described above, the folding mechanism of the present embodiment reduces the pushing force by pushing the sheet with the folding plate while pulling it with the folding roller, and the “folding plate moving speed ≧ folding roller peripheral speed” is passed. In addition, it is possible to prevent the occurrence of wrinkles and tears, and further, if "folding plate moving speed ≒ folding roller peripheral speed", the driving force of the folding roller and the folding plate can be minimized. It focuses on.

  As a mechanism for setting “the moving speed of the folding plate≈the peripheral speed of the folding roller”, it is difficult to control the moving speed of the folding plate with a conventional crank mechanism or a cam mechanism using an eccentric shaft. Therefore, as a mechanism for easily controlling the moving speed of the folding plate, the present embodiment is characterized in that a mechanism in which the rotation angle of the drive motor and the forward / backward movement amount of the folding plate are in a proportional relationship is adopted.

  According to the present embodiment, it is possible to provide an energy saving, low cost, high quality folding mechanism with a minimum driving force while solving the conventional problems. First, FIG. 1 is a cross-sectional view of the overall configuration of a sheet post-processing apparatus provided with a folding mechanism of the present embodiment. As shown in FIG. 1, the following description will be made on the assumption that the sheet post-processing apparatus having the folding mechanism of the present embodiment is attached to the image forming apparatus.

  As shown in FIG. 1, the sheet post-processing apparatus is attached to a side portion of the image forming apparatus, and the sheet discharged from the image forming apparatus is guided to the sheet post-processing apparatus. The paper passes through a transport path A having post-processing means (in this embodiment, a punch unit as a punching means) for performing post-processing on one sheet of paper, and is transported to a transport path B leading to the upper tray 201 and to the shift tray 202. The branch claw 15 and the branch claw 16 are configured to distribute the path C and the conveyance path D that leads to the processing tray F that performs alignment, stapling, and the like.

  The sheets that have been aligned and stapled in the processing tray F are distributed to the conveying tray C that leads to the shift tray 202, the processing tray G that is folded, and the like by the branch guide plate 54 and the movable guide 55 that are deflection means. The sheet that is configured and has been folded in the processing tray G is guided to the lower tray 203 through the conveyance path H.

  Further, a branching claw 17 is disposed in the conveyance path D, and is held in the state of FIG. 1 by a low load spring (not shown). It is configured such that at least the transport roller 9 of the staple paper discharge rollers 11 is reversed to guide and stay at the rear end to the paper storage unit E, and can be transported while being superposed on the next paper. By repeating this operation, it is possible to convey two or more sheets in a superimposed manner.

  In a common conveyance path A upstream of the conveyance path B, the conveyance path C, and the conveyance path D, an inlet sensor 301 that detects a sheet received from the image forming apparatus, an inlet roller 1, a punch unit 100, and a conveyance roller downstream thereof. 2, the branch claw 15 and the branch claw 16 are sequentially arranged. The branch claw 15 and the branch claw 16 are held in the state shown in FIG. 1 by a spring (not shown). By turning on a solenoid (not shown), the branch claw 15 is turned upward and the branch claw 16 is turned downward. By doing so, the paper is distributed to the conveyance path B, the conveyance path C, and the conveyance path D.

  When guiding the paper to the conveyance path B, the branching claw 15 is in the state shown in FIG. 1 and the solenoid is OFF. When guiding the paper to the conveyance path C, the branching claw 15 is moved upward by turning on the solenoid from the state shown in FIG. In addition, the branching claw 16 is rotated downward, and when the paper is guided to the conveyance path D, the branching claw 16 is in the state shown in FIG. 1, the solenoid is OFF, and the branching claw 15 is turned on from the state shown in FIG. By doing so, it will be in the state rotated upward.

  The paper stacking device included in the paper post-processing apparatus of the present embodiment includes a shift paper discharge roller 6, a return roller 13, a paper surface detection sensor 330, a shift tray 202, its lifting mechanism shown in FIG. The shift mechanism shown in FIG. In FIG. 3, reference numeral 13 denotes a sponge roller for contacting the paper discharged from the shift paper discharge roller 6 and abutting the rear end of the paper against an end fence 32 (not shown) for alignment.

  The return roller 13 is rotated by the rotational force of the shift paper discharge roller 6. A tray lift limit switch 333 is provided in the vicinity of the return roller. When the shift tray 202 is lifted and the return roller 13 is pushed up, the tray lift limit switch 333 is turned on and the tray lift motor 168 is stopped. Thereby, overrun of the shift tray 202 is prevented.

  As shown in FIG. 1, a paper surface detection sensor 330 is provided in the vicinity of the return roller 13 as paper surface position detecting means for detecting the paper surface position of the shift tray 202. Although not shown in FIG. 1, the paper surface detection sensor 330 includes the paper surface detection lever 30 shown in FIG. 3, a paper surface detection sensor (for staple) 330a, and a paper surface detection sensor (for non-stipple) 330b.

  The paper surface detection lever 30 is provided so as to be rotatable about its shaft portion, and has a contact portion 30 a that contacts the upper surface of the rear end of the paper loaded on the shift tray 202 and a fan-shaped shielding portion 30 b. The paper surface detection sensor (for stippling) 330a located above is mainly used for staple discharge control, and the paper surface detection sensor (for non-stipple) 330b is mainly used for shift discharge control.

  In the present embodiment, the paper surface detection sensor (for stipple) 330a and the paper surface detection sensor (for non-stipple) 330b are turned on when being blocked by the shielding portion 30b. Accordingly, when the shift tray 202 is raised and the contact portion 30a of the paper surface detection lever 30 is rotated upward, the paper surface detection sensor (for stippling) 330a is turned off, and when further rotated, the paper surface detection sensor (for non-stipple) 330b is turned on. To do. When it is detected by the paper surface detection sensor (for stippling) 330a and the paper surface detection sensor (for non-stipple) 330b that the paper stacking amount has reached a predetermined height, the shift tray 202 is lowered by a predetermined amount. Thereby, the paper surface position of the shift tray 202 is kept substantially constant.

  Next, the lifting mechanism of the shift tray 202 will be described in detail. As shown in FIG. 3, the shift tray 202 moves up and down by driving the drive shaft 21 by the drive unit. A timing belt 23 is tensioned between the drive shaft 21 and the driven shaft 22 via a timing pulley. The side plate 24 supporting the shift tray 202 is fixed to the timing belt 23, and the unit including the shift tray 202 is suspended so as to be lifted and lowered by such a configuration.

  Power generated by a tray lifting / lowering motor 168 capable of forward / reverse rotation as a drive source for moving the shift tray 202 in the vertical direction is transmitted to the final gear of the gear train fixed to the drive shaft 21 via the worm gear 25. It has become. Since the worm gear 25 is provided midway, the shift tray 202 can be held at a fixed position, and an accidental drop accident or the like of the shift tray 202 can be prevented.

  A shielding plate 24a is integrally formed on the side plate 24 of the shift tray 202, and a fullness detection sensor 334 for detecting the full load of stacked sheets and a lower limit sensor 335 for detecting a lower limit position are disposed below the shielding plate 24a. The full detection sensor 334 and the lower limit sensor 335 are turned on and off by the plate 24a. The fullness detection sensor 334 and the lower limit sensor 335 are photosensors, and are turned on when blocked by the shielding plate 24a. In FIG. 3, the shift paper discharge roller 6 is omitted.

  As shown in FIG. 2, the swing mechanism of the shift tray 202 rotates the shift cam 31 using a shift motor 169 as a drive source. A pin stands on the shift cam 31 at a position away from the center of the rotation shaft, and the end of the pin is guided in the direction orthogonal to the paper discharge direction by guiding the rear end of the loaded paper on the shift tray 202. The end fence, which is engaged with the pin by the rotation of the shift cam 31, moves in the direction orthogonal to the sheet discharge direction, and the shift tray 202 also moves accordingly. The shift tray 202 stops at two positions, the front and back, and the stop position is detected by the shift sensor 336 and is formed by turning on and off the shift motor 169.

  The shift paper discharge roller 6 has a drive roller 6a and a driven roller 6b. As shown in FIGS. 1 and 4, the driven roller 6b is supported on the upstream side in the paper discharge direction and is provided to be rotatable in the vertical direction. The open / close guide plate 33 is rotatably supported by a free end portion. The driven roller comes into contact with the driving roller 6a by its own weight or urging force, and the paper is nipped between the rollers and discharged.

  When the bound sheet bundle is discharged, the open / close guide plate 33 is rotated upward and returned at a predetermined timing. This timing is based on a detection signal of the shift paper discharge sensor 303. It is determined. The stop position is determined based on the detection signal of the paper discharge guide plate opening / closing sensor 331 and is driven by the paper discharge guide plate opening / closing motor 167.

  Next, the configuration of the processing tray F that performs the staple processing will be described in detail. As shown in FIG. 6, the sheets guided to the processing tray F by the staple paper discharge roller 11 are sequentially stacked. In this case, alignment in the vertical direction (paper conveyance direction) is performed by the tapping roller 12 for each sheet, and alignment in the horizontal direction (paper width direction orthogonal to the sheet conveyance direction) is performed by the jogger fence 53.

  The end-face stitching stapler S1 is driven by a staple signal from the control means 350 between job breaks, that is, between the last sheet of the sheet bundle and the first sheet of the next sheet bundle, and the binding process is performed. The sheet bundle subjected to the binding process is immediately sent to the shift paper discharge roller 6 by the discharge belt 52 having the discharge claw 52a, and is discharged to the shift tray 202 set at the receiving position.

  As shown in FIG. 7, the release claw 52a is configured such that its home position is detected by a release belt HP sensor 311. This release belt HP sensor 311 is turned on by a discharge claw 52a provided on the release belt 52. Turn off. Two discharge claws 52a are arranged at opposing positions on the outer periphery of the discharge belt 52, and the sheet bundle accommodated in the processing tray F is moved and conveyed alternately.

  Further, if necessary, the discharge belt 52 is reversely rotated, and the sheet bundle accommodated in the processing tray F on the back surface of the discharge claw 52a 'opposite to the discharge claw 52a waiting to move the sheet bundle. The tips in the transport direction may be aligned. As shown in FIG. 5, the discharge belt 52 and its driving pulley are arranged at the center of alignment in the paper width direction on the drive shaft of the discharge belt 52 driven by the discharge motor 157. 56 is fixed and the peripheral speed of the discharge roller 56 is set to be faster than the peripheral speed of the discharge belt 52.

  As shown in FIG. 6, the hitting roller 12 is given a pendulum motion by the hitting SOL 170 about the fulcrum 12 a and intermittently acts on the sheet fed to the processing tray F to hit the sheet against the rear end fence 51. The hitting roller 12 rotates counterclockwise. The jogger fence 53 is driven via a timing belt by a jogger motor 158 capable of forward and reverse rotation, and reciprocates in the paper width direction.

  As shown in FIG. 8, the end surface binding stapler S1 is driven via a timing belt by a forward / reversely movable stapler moving motor 159, and moves in the sheet width direction in order to bind a predetermined position of the sheet end. A stapler movement HP sensor 312 for detecting the home position of the end face binding stapler S1 is provided at one end of the moving range, and the binding position in the paper width direction is the amount of movement of the end face binding stapler S1 from the home position. Controlled by In the case of diagonal binding, after the end surface binding stapler S1 rotates in the direction of the arrow shown in FIG. 9, the diagonal binding processing is executed.

  As shown in FIGS. 1 and 5, in the saddle stitching stapler S2, the distance from the rear end fence 51 to the needle striking position of the saddle stitching stapler S2 corresponds to half of the conveyance direction length of the maximum sheet size that can be saddle stitched. Two are arranged so as to be more than the distance, and two are arranged symmetrically with respect to the alignment center in the paper width direction, and are fixed to the stay 63.

  Next, the configuration of the branch guide plate 54 and the movable guide 55 as the sheet bundle deflecting means will be described. As shown in FIGS. 10A to 10C, the branch guide plate 54 is provided so as to be rotatable in the vertical direction around the fulcrum 54a, and has a pressure roller 57 that is rotatable on the downstream side thereof. The discharge roller 56 is pressed by the spring 58. Further, the position of the branch guide plate 54 is determined by contacting with the cam surface 61a of the cam 61 that rotates by obtaining drive from the bundle branch drive motor 161.

  The movable guide 55 is rotatably supported on the rotation shaft of the discharge roller 56, and the movable guide 55 is provided with a link arm 60 that is rotatably connected. The link arm 60 is engaged with the shaft fixed to the side plate 64 shown in FIG. 5 by the elongated hole portion 60a, and thereby the rotation range of the movable guide 55 is restricted. Further, it is held at the position of FIG. Further, when the link arm 60 is pushed by the cam surface 61b of the cam 61 that rotates by obtaining the drive from the bundle branching drive motor 161, the connected movable guide 55 rotates upward.

  The cam 61 obtains its home position by detecting the bundle branch guide HP sensor with its shielding part 61c, and controls its stop position by the drive pulse of the bundle branch drive motor 161. FIG. 10A shows the positional relationship between the branch guide plate 54 and the movable guide 55 when the cam 61 is at the home position. The guide surface 55 a of the movable guide 55 has a function of guiding the paper in the path to the shift paper discharge roller 6.

  FIG. 10B shows that the branch guide plate 54 rotates downward as the cam 61 rotates, and the pressure roller 57 presses the discharge roller 56. In FIG. 10C, when the cam 61 further rotates, the movable guide 55 rotates upward, and a path that leads from the processing tray F to the processing tray G is formed by the branch guide plate 54 and the movable guide 55. It shows that.

  FIG. 5 shows the positional relationship in the depth direction. In this embodiment, the branch guide plate 54 and the movable guide 55 are operated by a single drive motor. However, each drive motor is provided so that the movement timing and stop position can be controlled according to the paper size and the number of sheets to be bound. You may do it.

  A conventional mechanism for moving the folding plate 74 will be described with reference to FIGS. 11 (a) and 11 (b). The folding plate 74 is supported by fitting the elongated hole portions 74a to the two shafts standing on the front and rear side plates, and the elongated hole portions 76b of the shaft portion 74b and the link arm 76 are fitted together. Swings about the fulcrum 76a, so that the folding plate 74 reciprocates left and right in FIGS. 11 (a) and 11 (b). The long hole portion 76c of the link arm 76 and the shaft portion 75b of the folding plate driving cam 75 are fitted together, and the link arm 76 swings by the rotational movement of the folding plate driving cam 75.

  The folding plate driving cam 75 is rotated in the arrow direction in FIGS. 11A and 11B by the folding plate driving motor 166. The stop position is determined by detecting both end portions of the half-moon shaped shielding portion 75a by the folding plate HP sensor 325. FIG. 11A shows the home position completely retracted from the sheet bundle accommodation area of the processing tray G. FIG. When the folding plate drive cam 75 is rotated in the direction of the arrow, the folding plate 74 moves in the direction of the arrow and protrudes into the sheet bundle accommodation area of the processing tray G.

  FIG. 11B shows a position where the center of the sheet bundle of the processing tray G is pushed into the nip of the folding roller 81. When the folding plate drive cam 75 is rotated in the direction of the arrow, the folding plate 74 moves in the direction of the arrow and retracts from the sheet bundle accommodation area of the processing tray G.

In the present embodiment, the following discharge mode is adopted according to the post-processing mode.
Non-stipple mode a: The paper is discharged to the upper tray 201 through the transport path A and the transport path B.
Non-stipple mode b: The paper is discharged to the shift tray 202 through the transport path A and the transport path C.
Sort, stack mode: The paper is discharged to the shift tray 202 through the transport path A and the transport path C. At that time, the sheets ejected by the shift tray 202 swinging in the direction orthogonal to the sheet ejection direction for each section separation are sorted.
Stipple mode: alignment and binding are performed in the processing tray F through the conveyance path A and the conveyance path D, and the sheet is discharged to the shift tray 202 through the conveyance path C.
Saddle-stitch bookbinding mode: alignment and center binding are performed on the processing tray F via the transport path A and transport path D, and center folding is performed on the processing tray G, and the paper is discharged to the lower tray 203 through the transport path H.

  The operation in the non-stipple mode a will be described below (see FIG. 14: steps 101 to 107). The paper sorted by the branching claw 15 from the conveyance path A is guided to the conveyance path B and discharged to the upper tray 201 by the conveyance roller 3 and the upper paper discharge roller 4. The state of paper discharge is monitored by an upper paper discharge sensor 302 that is disposed in the vicinity of the upper paper discharge roller 4 and detects the discharge of the paper.

  The operation in the non-stipple mode b will be described below (see FIG. 15: steps 201 to 209). From the conveyance path A, the paper sorted by the branch claw 15 and the branch claw 16 is guided to the conveyance path C, and is discharged to the shift tray 202 by the conveyance roller 5 and the shift discharge roller 6. Further, the state of paper discharge is monitored by a shift paper discharge sensor 303 that is disposed in the vicinity of the shift paper discharge roller 6 and detects the discharge of the paper.

  The operations in the sort and stack modes will be described below (see FIG. 16: steps 301 to 313). The same sheet ejection as in the non-stipple mode b is performed. At that time, the sheets ejected by the shift tray 202 swinging in the direction orthogonal to the sheet ejection direction for each section separation are sorted.

  The operation in the stipple mode will be described below (see FIG. 17: steps 401 to 430). From the conveyance path A, the paper sorted by the branching claw 15 and the branching claw 16 is guided to the conveyance path D and discharged to the processing tray F by the conveyance roller 7, the conveyance roller 9, the conveyance roller 10, and the staple discharge roller 11. The In the processing tray F, the sheets sequentially discharged by the paper discharge roller 11 are aligned, and when the predetermined number of sheets is reached, the end surface binding stapler S1 performs the binding process.

  Thereafter, the bound sheet bundle is conveyed downstream by the discharge claw 52 a and discharged to the shift tray 202 by the shift discharge roller 6. Further, the state of paper discharge is monitored by a shift paper discharge sensor 303 that is disposed in the vicinity of the shift paper discharge roller 6 and detects the discharge of the paper.

  The operation of the processing tray F in the stipple mode will be described. When the stipple mode is selected, as shown in FIG. 6, the jogger fence 53 moves from the home position and stands by at a standby position that is 7 mm away from the width of the paper discharged to the processing tray F. When the paper is conveyed by the staple paper discharge roller 11 and the rear end of the paper passes through the staple paper discharge sensor 305, the jogger fence 53 moves inward by 5 mm from the standby position and stops.

  Further, the staple paper discharge sensor 305 detects that when the trailing edge of the paper passes, and the signal is input to the CPU 360 (see FIG. 13). The CPU 360 shown in FIG. 13 counts the number of pulses transmitted from a not-shown staple transport motor 155 that drives the staple paper discharge roller 11 from the time of receiving this signal, and turns on the SOL 170 after transmitting a predetermined pulse.

  The tapping roller 12 performs a pendulum motion when the tapping SOL 170 is turned on and off. When the tapping roller 12 is on, the tapping roller 12 strikes the sheet and returns it to the lower side, and abuts against the rear end fence 51 to align the paper. At this time, every time the paper stored in the processing tray F passes the entrance sensor 101 or the staple paper discharge sensor 305, the signal is input to the CPU 360, and the number of papers is counted.

  After a lapse of a predetermined time after the beating SOL 170 is turned off, the jogger fence 53 is further moved inward by 2.6 mm by the jogger motor 158, temporarily stops, and the horizontal alignment is finished. The jogger fence 53 then moves outward by 7.6 mm, returns to the standby position, and waits for the next sheet. This operation is performed up to the last page. After that, it moves again inward by 7 mm and stops, and prepares for a stippling operation by pressing both ends of the sheet bundle.

  Then, after a predetermined time, the end face binding stapler S1 is operated by a staple motor (not shown), and the binding process is performed. If two or more bindings are designated at this time, after one binding process is completed, the staple movement motor 159 is driven, and the end-face binding stapler S1 is moved to an appropriate position along the rear edge of the sheet. The second stitching process is performed. If the third and subsequent locations are specified, this is repeated.

  When the binding process is completed, the discharge motor 157 is driven, and the discharge belt 52 is driven. At this time, the paper discharge motor is also driven, and the shift paper discharge roller 6 starts to rotate so as to accept the sheet bundle lifted by the discharge claw 52a. At this time, the jogger fence 53 is controlled to be different depending on the paper size and the number of sheets to be bound. For example, when the number of sheets to be bound is less than the set number or smaller than the set size, the trailing edge of the sheet bundle is hooked and conveyed by the discharge claw 52a while the sheet bundle is pressed by the jogger fence 53.

  Then, the jogger fence 53 is retracted 2 mm after a predetermined pulse from the detection by the paper presence sensor 310 or the discharge belt HP sensor 311, and the restriction on the paper by the jogger fence 53 is released. This predetermined pulse is set after the discharge claw 52a comes into contact with the rear end of the paper and passes through the front end of the jogger fence 53.

  When the number of sheets to be bound is larger than the set number or larger than the set size, the jogger fence 53 is retracted in advance by 2 mm and discharged. In any case, when the sheet bundle passes through the jogger fence 53, the jogger fence 53 moves further outward by 5 mm and returns to the standby position to prepare for the next sheet. It is also possible to adjust the binding force according to the distance of the jogger fence 53 to the paper.

  The operation in the saddle stitch binding mode will be described below (see FIG. 18: steps 501 to 538). From the conveyance path A, the paper sorted by the branch claw 15 and the branch claw 16 is guided to the conveyance path D and discharged to the processing tray F by the conveyance roller 7, the conveyance roller 9, the conveyance roller 10, and the staple paper discharge roller 11. Is done. In the processing tray F, the sheets sequentially discharged by the discharge rollers 11 are aligned as in the stipple mode, and the same operation is performed until just before stapling (see FIG. 12A).

  Thereafter, the sheet bundle is conveyed downstream by a predetermined distance set for each sheet size by the discharge claw 52a to the position of FIG. 12B, and the center thereof is bound by the saddle stitching stapler S2. At the position shown in FIG. 12 (c), the bound sheet bundle is conveyed downstream by a discharge claw 52a for a predetermined distance set for each sheet size and temporarily stops. This moving distance is managed by the drive pulse of the discharge motor 157.

  Thereafter, as shown in FIG. 12C, the leading end of the sheet bundle is sandwiched between the discharge roller 56 and the pressure roller 57, and is formed by turning the branch guide plate 54 and the movable guide 55 to the processing tray G. In order to pass through the guided path, it is again conveyed downstream by the discharge claw 52 a and the discharge roller 56. The discharge roller 56 is provided on the drive shaft of the discharge belt 52 and is driven in synchronization with the discharge belt 52.

  Then, as shown in FIG. 12D, the sheet bundle is moved from the home position to a position corresponding to the sheet size in advance by the upper bundle conveying roller 71 and the lower bundle conveying roller 72 to guide the lower end face. It is conveyed to the movable rear end fence 73 stopped as much as possible. At this time, the discharge claw 52a stops at the position where another discharge claw 52a 'disposed at a position facing the outer periphery of the discharge belt 52 reaches the vicinity of the rear end fence 51, and the branch guide plate 54 and the movable guide 55 returns to the home position and prepares for the next sheet.

  As shown in FIG. 12D, the sheet bundle abutted against the movable rear end fence 73 is released from the pressurization of the lower bundle conveying roller 72. Thereafter, as shown in FIG. 12 (f), the vicinity of the bound needle portion is pushed by the folding plate 74 in a substantially right-angle direction and guided to the nip of the opposing folding roller 81. The folding roller 81 folds the center of the sheet bundle by conveying the sheet bundle under pressure.

  As shown in FIG. 12G, when the folded sheet bundle leading end is detected by the folding portion passage sensor 323, the folding plate 74 returns to the home position. Thereafter, the sheet is discharged to the lower tray 203 by the lower sheet discharge roller 83 as shown in FIG. At this time, when the trailing edge of the sheet bundle is detected by the bundle arrival sensor 321, the movable trailing edge fence 73 is returned to the home position, and the pressurization of the lower bundle conveying roller 72 is restored to prepare for the next sheet. If the next job is the same sheet size and the same number of sheets, the movable rear end fence 73 may stand by at that position.

  As shown in FIG. 13, the control means 350 is a microcomputer having a CPU 360, an I / O interface 370, etc., and each switch of a control panel of the image forming apparatus main body (not shown) and each sensor such as a paper surface detection sensor 330. Are input to the CPU 360 via the I / O interface 370.

  The CPU 360 drives the tray lifting / lowering motor 168 for the shift tray 202, the discharge guide plate opening / closing motor 167 for opening / closing the opening / closing guide plate, the shift motor 169 for moving the shift tray 202, and the tapping roller 12 based on the input signal. The hitting roller motor 156, the solenoids such as the hitting SOL 170, the transfer motors that drive the transfer rollers, the discharge motors that drive the discharge rollers, the discharge motor 157 that drives the discharge belt 52, and the stapler that moves the end face binding stapler S1. A moving motor 159, an oblique motor 160 that obliquely rotates the end-face stitching stapler S1, a jogger motor 158 that moves the jogger fence 53, a bundle branch drive motor 161 that rotates the branch guide plate 54 and the movable guide 55, and the bundle is conveyed. Bundle conveyance motor 162 for driving the conveyance roller Rear end fence moving motor 163 for moving the movable rear fence 73, the folding plate driving motor 166 to move the folding plate 74, controls the driving of such folding roller driving motor 164 for driving the folding rollers 81.

  A pulse signal of a not-shown staple transport motor 155 for driving the staple discharge roller is input to the CPU 360 and counted, and the hitting SOL 170 and the jogger motor 158 are controlled according to this count.

  Next, in the folding mechanism of this embodiment, a screw mechanism can be used to drive the folding plate 74. As shown in FIGS. 19A and 19B, the folding plate 74 is connected to a ball screw (screw mechanism) 501, and is connected to a motor 166 through a gear at an end thereof, and is moved by the rotation of the motor 166. To do. The home position is detected by the sensor 325 and stopped. (Claims 2 and 3)

  In the folding mechanism of this embodiment, a spiral cam mechanism can be used to drive the folding plate 74. As shown in FIG. 20, the folding plate 74 is driven by using a spiral cam mechanism in which the rotation angle and the rotation radius of the spiral groove are in a proportional relationship, and the folding plate 74 guide rod (folding plate guide rod 401). ) Are engaged with the cam groove. The spiral cams (cam 402a and cam 402b) are driven as shown in FIG. 21, and the two cams (cam 402a and cam 402b) always operate synchronously and move forward and backward depending on the rotation direction. To do. (Claim 4)

  Further, the folding mechanism of the present embodiment can be configured as shown in FIGS. The guide member 403 shown in FIGS. 20 and 22 slides while swinging along the cam groove shape around the folding plate guide rod 401. When the guide member 403 is not provided, the contact area between the rod and the cam is small as shown in FIG. 23, and when the guide member 403 is provided, the pressure is increased as shown in FIG. I understand that. This makes it possible to use a resin material, which can contribute to light weight and low cost. (Claim 5)

  In the folding mechanism according to claim 1, as a mechanism for setting “the moving speed of the folding plate≈the peripheral speed of the folding roller”, a mechanism that easily controls the moving speed of the folding plate (the rotation angle of the drive motor and the folding plate) By adopting a mechanism in which the amount of forward / backward movement is in a proportional relationship, it provides an energy-saving, low-cost, high-quality folding mechanism with minimal driving force while eliminating conventional problems (such as wrinkles and tears). It becomes possible. If a pulse motor is used as the drive motor, the speed can be controlled more easily.

  In the folding mechanism according to claims 2 and 3, since the screw mechanism such as a ball screw is used for driving the folding plate, the speed can be controlled with high accuracy, and also has a role of decelerating, and is strongly stopped against a high load. Excellent holding power to maintain the state, it is very effective for energy saving and space saving. However, when it is installed at both ends of the folding plate, there is a part that the phase is difficult to adjust and the cost is somewhat high.

  In the folding mechanism according to claim 4, since the spiral cam mechanism in which the rotation angle and the rotation radius of the spiral groove are in a proportional relationship is used for driving the folding plate, the advantage of using a screw mechanism is provided. If the end of the spiral groove is used, there is no difficulty in adjusting the phase even when it is attached to both ends of the folding plate. If the outer periphery of the cam is used as a driving gear, the speed reduction mechanism can be obtained. It can be simplified, and energy saving, space saving, and low cost can be achieved.

  6. The folding mechanism according to claim 5, wherein a slanted ball-shaped guide member having a curvature similar to the curvature of the cam groove is used for engagement between the cam groove and the folding plate guide rod, so that the cylinder can be formed even when it is made of a resin material. As a result, the contact area of the cam groove can be ensured wider than that of the cam groove, so that the pressure can be dispersed and a high load can be endured, and the weight and cost can be reduced.

1 is an overall configuration cross-sectional view of a sheet post-processing apparatus including a folding mechanism according to an embodiment. FIG. 4 is a perspective view showing a shift mechanism of a paper stacking device included in the paper post-processing device of the present embodiment. It is the perspective view which showed the raising / lowering mechanism of the paper stacking apparatus which the paper post-processing apparatus of this embodiment has. It is a perspective view for explaining a shift mechanism of a paper stacking device included in the paper post-processing device of the present embodiment. It is sectional drawing for demonstrating the paper post-processing apparatus of this embodiment. FIG. 6 is a perspective view and a cross-sectional view for explaining a configuration of a processing tray F that performs a staple process in the paper post-processing apparatus of the present embodiment. FIG. 6 is a perspective view and a cross-sectional view for explaining a configuration of a processing tray F that performs a staple process in the paper post-processing apparatus of the present embodiment. FIG. 6 is a perspective view for explaining an end-face stitching stapler S1 in the sheet post-processing apparatus of the present embodiment. FIG. 6 is a perspective view for explaining an end-face stitching stapler S1 in the sheet post-processing apparatus of the present embodiment. FIG. 5A is a cross-sectional view for explaining the configuration of a branch guide plate 54 and a movable guide 55 as a sheet bundle deflecting unit of the sheet post-processing apparatus of the present embodiment. FIG. 5B is a cross-sectional view for explaining the configuration of a branch guide plate 54 and a movable guide 55 as a sheet bundle deflecting unit of the sheet post-processing apparatus of the present embodiment. (C) is a cross-sectional view for explaining the configuration of a branch guide plate 54 and a movable guide 55 as a sheet bundle deflecting unit of the sheet post-processing apparatus of the present embodiment. (A) is a figure for demonstrating the moving mechanism of the conventional folding plate 74. FIG. (B) is a figure for demonstrating the moving mechanism of the conventional folding plate 74. FIG. (A) is sectional drawing for demonstrating operation | movement of the saddle stitch bookbinding mode in the paper post-processing apparatus of this embodiment. FIG. 5B is a cross-sectional view for explaining the operation in the saddle stitch binding mode in the sheet post-processing apparatus of the present embodiment. FIG. 6C is a cross-sectional view for explaining the operation in the saddle stitch binding mode in the sheet post-processing apparatus of the present embodiment. FIG. 6D is a cross-sectional view for explaining the operation in the saddle stitch binding mode in the sheet post-processing apparatus of the present embodiment. FIG. 6E is a cross-sectional view for explaining the operation in the saddle stitch binding mode in the sheet post-processing apparatus of the present embodiment. FIG. 6F is a cross-sectional view for explaining the operation in the saddle stitch binding mode in the sheet post-processing apparatus of the present embodiment. (G) is sectional drawing for demonstrating operation | movement of the saddle stitch bookbinding mode in the paper post-processing apparatus of this embodiment. (H) is a cross-sectional view for explaining the operation in the saddle stitch binding mode in the sheet post-processing apparatus of the present embodiment. It is a block diagram for demonstrating the paper post-processing apparatus of this embodiment. 6 is a flowchart for explaining an operation in a non-stipple mode a in the sheet post-processing apparatus of the present embodiment. 6 is a flowchart for explaining an operation in a non-stipple mode b in the sheet post-processing apparatus of the present embodiment. 6 is a flowchart for explaining operations in sort and stack modes in the sheet post-processing apparatus of the embodiment. 6 is a flowchart for explaining an operation in a stipple mode in the sheet post-processing apparatus of the embodiment. 6 is a flowchart for explaining an operation in a saddle stitch binding mode in the sheet post-processing apparatus of the embodiment. (A) is sectional drawing for demonstrating the screw mechanism used for the drive of the folding plate 74 in the folding mechanism of this embodiment. (B) is sectional drawing for demonstrating the screw mechanism used for the drive of the folding plate 74 in the folding mechanism of this embodiment. In the folding mechanism of this embodiment, it is a perspective view for demonstrating the spiral cam mechanism used for the drive of the folding plate 74. FIG. In the folding mechanism of this embodiment, it is a perspective view for demonstrating the spiral cam mechanism used for the drive of the folding plate 74. FIG. In the folding mechanism of this embodiment, it is a perspective view for demonstrating the spiral cam mechanism used for the drive of the folding plate 74. FIG. In the folding mechanism of this embodiment, it is a perspective view for demonstrating the spiral cam mechanism used for the drive of the folding plate 74. FIG. In the folding mechanism of this embodiment, it is a perspective view for demonstrating the spiral cam mechanism used for the drive of the folding plate 74. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Entrance roller 2, 3 Conveyance roller 4 Upper discharge roller 5, 7 Conveyance roller 6 Shift discharge roller 8 Prestack roller 9, 10 Conveyance roller 11 Staple discharge roller 12 Tapping roller 13 Return roller 15-17 Branching claw 21 Drive Shaft 22 Followed shaft 23 Timing belt 24 Side plate 25 Worm gear 30 Paper surface detection lever 31 Shift cam 32 End fence 33 Opening / closing guide plate 51 Rear end fence 52 Release belt 52a Release claw 53 Jogger fence 54 Branch guide plate 55 Movable guide 55a Movable guide 1 side surface 56 Release roller 57 Pressure roller 58, 59 Spring 60 Link arm 61 Cam 62 Release belt drive pulley 63 Stay 64 Side plate 64a Front side plate 64b Rear side plate 65 Release shaft 71 Upper bundle conveyance roller 72 Lower bundle conveyance roller 73 Movable End fence 74 Folding plate 75 Folding plate drive cam 76 Link arm 81, 82 Folding roller 83 Lower paper discharge roller 91 Lower bundle conveyance guide plate 92 Upper bundle conveyance guide plate 100 Punch unit 101 Punch waste hopper 157 Discharge motor 158 Jogger motor 159 Stipler Movement motor 160 Diagonal motor 161 Bundle branch drive motor 167 Discharge guide plate opening / closing motor 168 Tray lift motor 169 Shift motor 170 Tapping SOL
201 Upper tray 202 Shift tray 203 Lower tray 301 Entrance sensor 302 Upper paper discharge sensor 303 Shift paper discharge sensor 304 Pre-stack sensor 305 Stipple paper discharge sensor 310 Paper presence sensor 311 Discharge belt HP sensor 312 Stapler movement HP sensor 313 Stipler oblique HP sensor 315 Bundle branch guide HP sensor 321 Bundle arrival sensor 322 Movable rear end fence HP sensor 323 Folding section passage sensor 324 Lower paper discharge sensor 325 Folding plate HP sensor 330 Paper surface detection sensor 330a Paper surface detection sensor (for staple)
330b Paper surface detection sensor (for non-stipple)
331 Discharge guide plate opening / closing sensor 332 Discharge guide plate opening / closing limit SW
333 Tray rising limit SW
334 Full detection sensor 335 Lower limit sensor 336 Shift sensor 350 Control means 360 CUP
370 I / O interface 401 Folding plate guide rod 402a, 402b Cam 403 Guide member

Claims (9)

A folding plate that is movable in a direction substantially perpendicular to the sheet conveyance path;
A pair of folding rollers exposed in the sheet conveying path;
A folding mechanism that folds the sheet, and a driving motor that drives the pair of folding rollers,
A folding mechanism characterized in that the rotation angle of the drive motor and the amount of forward / backward movement of the folding plate are in a proportional relationship.   2. The folding mechanism according to claim 1, wherein a screw mechanism is used for driving the folding plate.   The folding mechanism according to claim 2, wherein the screw mechanism is a ball screw.   The folding mechanism according to claim 1, wherein a spiral cam mechanism is used for driving the folding plate. A folding plate guide rod for guiding the folding plate;
5. A folding mechanism according to claim 4, wherein a slanted-shaped guide member having a curvature approximate to the curvature of the cam groove is used for engagement between the spiral cam groove and the folding plate guide rod.   A sheet folding apparatus comprising the folding mechanism according to claim 1.   A sheet post-processing apparatus having the folding mechanism according to claim 1.   An image forming apparatus comprising the folding mechanism according to claim 1. A folding plate that is movable in a direction substantially perpendicular to the sheet conveyance path;
A pair of folding rollers exposed in the sheet conveying path;
A sheet folding method of a folding mechanism for folding a sheet, comprising: a drive motor that drives the pair of folding rollers;
A sheet folding method for a folding mechanism, wherein the rotation angle of the drive motor and the amount of forward / backward movement of the folding plate are in a proportional relationship.

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