JP2012188226A - Paper sheet processing apparatus, and image forming system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect failure early, when a paper sheet to be stacked is highly deformed and thereby the deformation may cause malfunction, regardless of the deformation caused position.SOLUTION: A paper sheet processing apparatus includes: an interior tray 102 on which conveyed paper sheets are stacked; a distance detection portion 202 that a distance to the paper sheet P or a paper sheet bundle PB stacked on the interior tray 102; a vertical movement mechanism 208 that moves the distance detection portion 202 with respect to the paper sheet or the paper sheet bundle; and a CPU that recognizes a state of the paper sheet P deformation on the basis of a changing state of the distance detected in succession by the distance detection portion 202 while being moved by the vertical movement mechanism 208. The vertical movement mechanism 208 moves the distance detection portion 202 vertically with respect to a paper sheet-stacking face of the interior tray 102 and scans an end face of the paper sheet P.

Description

  The present invention relates to a sheet processing apparatus and an image forming system, and in particular, curling of a sheet member (hereinafter simply referred to as “sheet”) such as a loaded sheet, a recording sheet, and a sheet-like recording medium. The present invention relates to an image forming system including a sheet processing apparatus including a detecting unit and an image forming apparatus including the sheet processing apparatus.

  In a paper post-processing apparatus that performs predetermined paper processing, that is, so-called post-processing, on paper conveyed from the image forming apparatus, the curl size of the paper discharged to the paper output tray is detected, and depending on the size, the paper is discharged. A technique for stopping paper is known. For example, in Patent Document 1 (Japanese Patent Laid-Open No. 2003-026370), a plurality of distance measuring sensors corresponding to the paper size are provided on the bottom surface of a discharge tray that can be moved up and down, and the center of the sheet on the discharge tray below that is provided. An invention is disclosed in which a distance to a nearby upper surface (sensor output voltage) is detected, and when a large change continues for a predetermined time, it is determined that a stacking abnormality has occurred and paper discharge is stopped.

  However, in the invention described in Patent Document 1, since the distance detecting means is fixed and can be detected only when the sheet is rounded at the center of the sheet, it can be detected when the sheet is rounded at the center of the sheet. However, when the paper rounding position deviates from the detection target position of the fixed distance detecting means, the detection of the rounding becomes impossible, so that it may be detected early depending on the rounding occurrence position and the configuration of the paper discharge tray. In some cases, there are problems such as generation of discarded paper due to a paper jam, dropping of paper, and the like. Further, there are face curl and back curl in the deformation of the paper at the time of paper discharge, and the folding part may return after folding on the paper that has been subjected to folding processing. In any case, when the deformation becomes large, the same problem as in the case of rounding occurs.

  Therefore, the problem to be solved by the present invention is to detect an abnormality at an early stage regardless of the occurrence position when the deformation of the loaded paper becomes large and there is a possibility that a malfunction may occur due to the deformation. Is to make it.

  In order to solve the above-mentioned problem, the first means includes a stacking unit on which the conveyed sheets are stacked, a distance detection unit that detects a distance to a sheet or sheet bundle stacked on the stacking unit, Recognizing the deformation state of the sheet based on the moving means for moving the distance detecting means relative to the sheet or the sheet bundle and the change state of the distance continuously detected by the distance detecting means while moving by the moving means. And a sheet processing device including a sheet state recognition unit.

  In this case, the moving unit moves the distance detecting unit in a direction perpendicular to the sheet stacking surface of the stacking unit, and scans the end surface of the sheet. In addition, the end face of the paper can be scanned by moving the distance detecting means in a direction parallel to the end face of the paper of the stacking means. In this case, the distance detecting means can be provided at any one or more of the front, rear, and side surfaces in the paper transport direction. The distance detecting means may be moved along the upper surface of the sheet or sheet bundle in the main scanning direction and / or the sub-scanning direction with respect to the sheet conveying direction to scan the upper surface of the sheet or sheet bundle.

  It is also possible to provide a control means for changing the transport destination of the paper or stopping the transport when the paper status recognition means recognizes that the deformation state of the paper is abnormal. When the paper state recognizing means recognizes that the deformation state of the paper is abnormal, the control means continues to carry the paper being conveyed in the previous stage from the previous stage. The abnormality is, for example, when the deformation state of the paper including one of face curl, back curl, rounding and folding height is regarded as abnormal, and the abnormality is paper conveyance or discharge depending on the degree of deformation. This means that there is a risk of paper defects.

  The paper state recognition unit starts the movement of the distance detection unit from above when the stacking unit can be moved up and down, and starts from below when the stacking unit cannot be moved up and down.

  The second means is characterized by an image forming system including a paper processing apparatus according to the first means and an image forming apparatus that forms an image on paper.

  In the embodiments described later, the sheet is denoted by P, the stacking means is denoted by the inner trays 102 and 102a and the outer tray 302, the sheet bundle is denoted by PB, the distance detecting means is denoted by the distance detecting unit 202, and the moving means is driven in the vertical direction. The mechanism 208 or the horizontal movement mechanism 228, the sheet state recognition means to the CPU 401, the sheet processing apparatus to the stackers 100-1 and 100-2, or the sheet post-processing apparatus 300, the main scanning direction is the arrow y direction, and the sub-scanning direction. Is the arrow x direction, the vertical direction is the arrow z direction, the control means is the CPU 401, the front stage is the image forming apparatus PR, the face curl is in the state of the paper P1, the back curl is in the state of the paper P2, and the round is the paper P3. The state corresponds to the state of the sheet P4, and the image forming apparatus corresponds to the symbol PR.

  According to the present invention, when the deformation of the stacked paper becomes large and there is a possibility that a malfunction may occur due to the deformation, it is possible to detect an abnormality at an early stage regardless of the generation position.

1 is a schematic configuration diagram showing an outline of the overall configuration of a stacker as a paper processing apparatus according to Example 1 of an embodiment of the present invention; It is a front view which shows the state which installed the curl state recognition unit in the stacker of FIG. It is a front view which shows the structure of the curl state recognition unit in a state where the distance detection unit is at the top. It is a front view which shows the structure of the curl state recognition unit in a state where the distance detection unit is at the lowest position. FIG. 10 is an explanatory diagram illustrating a principle of recognition detection of a curled state of a stack of sheets stacked on an internal tray. It is a flowchart which shows the control procedure in case the paper of the control of recognizing a curl state is not folded using a curl state recognition unit. It is a flowchart which shows the control procedure in case a paper of the control which recognizes a curl state using a curl state recognition unit has folding. It is a block diagram which shows the control structure of the image forming system which performs curl state recognition control. It is a figure which shows the state which has the curl state recognition unit which is movable also in a horizontal direction in the near side. It is a figure which shows the state which has the curl state recognition unit which is movable also in a horizontal direction in the back side. It is a flowchart which shows the control procedure of curl state recognition control when a shift position is changed. It is explanatory drawing which shows the recognition detection principle of a curl state by installing a curl state recognition unit downward on the side plate on the inner upper side of the stacker. 6 is a flowchart illustrating a control procedure of curl state recognition control when a mode for measuring two corners of a sheet is set. FIG. 10 is a schematic configuration diagram illustrating an outline of an entire stacker as a paper processing apparatus according to a second embodiment. FIG. 6 is a perspective view showing an overall configuration of a fixed internal tray in Embodiment 2. FIG. 10 is a schematic configuration diagram illustrating an outline of an entire sheet post-processing apparatus as a sheet processing apparatus according to a third embodiment.

  In the present invention, when detecting the roundness of the paper on the paper discharge tray, the distance to the paper is continuously detected while moving the distance detecting means on the end face or the top surface of the paper on the paper discharge tray, and the occurrence of the rounding is detected. It is characterized in that roundness can be detected regardless of position.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an outline of the overall configuration of a sheet stacking apparatus as a sheet processing apparatus according to Example 1 of the embodiment of the present invention, a so-called stacker. The internal tray in the stacker is moved to the sheet discharge position. Shows the state when rising. The paper discharged from the image forming apparatus is carried in from the direction of arrow A. The stacker 100-1 according to the first exemplary embodiment can select a proof paper discharge mode, a straight paper discharge mode, and a shift paper discharge mode, and the paper transport direction is controlled according to each mode. . The proof paper discharge mode is an operation mode in which paper is guided from the paper transport path proof transport path 141 onto the proof tray 101 and stacked. The straight sheet discharge mode is an operation mode in which the sheet is guided from the straight conveyance path 142 to the subsequent sheet post-processing apparatus. The shift discharge mode is an operation mode in which sheets are discharged from the shift conveyance path 143 onto the internal tray 102 and stacked. In the shift discharge mode, a predetermined number of sheets are stacked at different shift positions on the internal tray 102. The shift operation is performed by a main jogger pair 150 and a sub jogger pair 151 which will be described later.

  In the stacker 100-1, when the sheets are stacked, when the carriage 108 is set at a predetermined position of the stacker 100-1 with the front door (not shown) opened, and the front door is closed, the tray on the carriage 108 is placed. 102 is raised by the elevator 103. The drive source of the elevator 103 is a tray lifting / lowering motor 107. The tray lifting / lowering motor 107 is rotated by a control signal from a CPU (not shown) to raise the elevator 103.

  A pulley is press-fitted into the rotating shaft of the tray lifting / lowering motor 107, and a driving force generated by the rotation of the tray lifting / lowering motor 107 is transmitted via a timing belt. A gear group including a worm gear 106 and gears 109, 110 and 105 is connected to the tip of the timing belt, and the gear 105 is connected to the timing belt 104. For example, when the tray lifting / lowering motor 107 rotates forward, force is transmitted to the timing belt 104 by the connected gear, and the elevator (internal tray holding plate pair) 103 that lifts and lowers the tray 102 connected to the timing belt 104 is raised. On the other hand, when the tray lifting / lowering motor 107 rotates in the reverse direction, the elevator 103 is lowered.

 The stacker 100-1 includes a transport mechanism in addition to the tray mechanism that stacks and discharges the sheets. The conveyance mechanism discharges the sheet conveyed from the image forming apparatus PR side to the tray 102 or conveys it to the subsequent sheet processing apparatus. The proof conveyance path 141, the straight conveyance path 142, and the shift conveyance path 143. , A lower branch claw 120, and an upper branch claw 121. The lower branching claw 120 is a branching claw that switches the paper carried from the entrance roller 114 to the shift conveyance path 143 side or the straight conveyance path 142 side, and the upper branching claw 121 proofs the sheet guided to the lower branching claw 120. A branch claw that switches between the conveyance path 141 side and the straight conveyance path 142 side. The proof conveyance path 141 is a conveyance path for discharging a sheet to the proof tray 101, and is a conveyance path from the upper branch claw 121 to the proof tray 101. The straight 142 is a conveyance path for conveying the sheet to the subsequent sheet processing apparatus, and is a conveyance path from the entrance portion to the sheet discharge portion. The shift conveyance path 143 is a conveyance path for discharging a sheet to the tray 102 and is a conveyance path from the lower branch claw 120 to the sheet 102.

 A transport roller (paper discharge) 111 for discharging paper to the internal tray 102 and a spring urged and pressed against the paper discharge roller 111 at the most downstream portion of the shift transport path 143 in the paper transport direction. A driven roller 113 is provided, and a sheet is nipped between the rollers 111 and 113. An entrance sensor 131 and a paper transport path sensor 132 are provided along the paper transport path, and a paper surface sensor 133 is disposed in the vicinity of the paper discharge portion of the paper discharge roller 111. A plurality of conveyance rollers are arranged in each of the sheet conveyance paths 141, 142, and 143, and are driven by a driving mechanism (not shown) to convey the sheet to a predetermined position. In addition, a proof discharge sensor 134 is disposed immediately before the tray 101 in the proof conveyance path 101, a full detection sensor 135 is disposed above the proof tray 101, and sheet detection sensors 136 and 137 are disposed in the straight conveyance path 142, respectively. Yes.

  In the stacker 100-1, which is roughly configured as described above, when the sheet conveyed from the image forming apparatus is received by the entrance roller 114 and then discharged to the proof tray 101, the lower branch claw 120 and the upper branch claw 121 are provided. The sheet is rotated in the clockwise direction in the drawing, the conveyance path corresponding to the upper side of each branch claw is opened, guided to the proof conveyance path 141, and discharged from the proof conveyance path 141 to the proof tray 101. When paper is discharged to the sheet post-processing device connected downstream of the stacker 100-1, the lower branch claw 120 is rotated in the clockwise direction in the figure, and the upper branch claw 121 is rotated in the counterclockwise direction in the figure, so that the sheet is conveyed straight. The paper is guided to 142 and discharged to a paper post-processing apparatus connected downstream. When paper is discharged to the internal tray 102 disposed in the stacker 100-1, the lower branch claw 120 is rotated counterclockwise in the drawing, the shift conveyance path 143 side is opened, and the paper is discharged to the internal tray 102. . Thereafter, the stopper 152 aligns the paper in the sub-scanning direction (alignment in the paper transport direction), and the main jogger pair 150 and the sub-jogger pair 151 aligns the main scanning direction (alignment in the direction orthogonal to the paper transport direction).

  A paper surface detection filler 153 is provided above the internal tray 102, and when a paper is stacked on the internal tray 102, the front end of the paper surface detection filler 153 is pushed up and rotated to turn the rear end of the first paper surface detection sensor 154. The optical path is cut off, and the filler position is detected by the first paper surface detection sensor 154, so that the paper stacking can be known. After the detection, when the tray lifting / lowering motor 107 is driven to lower the elevator 103, the internal tray 102 installed thereon is also lowered. Then, the tray lifting / lowering motor 107 is stopped a predetermined time after the first paper surface detection sensor 154 is not detected. When the paper is removed from the internal tray 102, the leading end of the paper surface detection filler 153 is lowered, the rear end blocks the optical path of the second paper surface detection sensor 155, the filler position is detected, and it can be seen that the paper has been removed. . After the detection, the tray lifting / lowering motor 107 is driven to raise the internal tray 102, and the tray lifting / lowering motor 107 is stopped after a predetermined time after the second paper surface detection sensor 155 is not detected.

  As described above, the tray lifting / lowering motor 107 is operated, and the internal tray 102 when the paper is not stacked and the internal tray 102 when the paper is stacked with respect to the discharge port to the internal tray 102 (nip position with respect to the rollers 111 and 113). Control is performed so that the height of the uppermost sheet of the upper sheet is constant.

  FIG. 2 is a front view showing a state in which the curl state recognition unit is installed in the stacker of FIG. As shown in the figure, the curl state recognition unit 200 is fixedly installed on the side plate 100a inside the housing of the stacker 100-1. Although it is installed on the left inner side plate 100a in FIG. 2, it may be installed on the right inner side plate 100b or the upper inner side plate 100c. In this embodiment, the sheet is described as curling in the sub-scanning direction. However, when the sheet is curled in the main scanning direction, the sheet is installed on the back side plate.

  3 and 4 are front views showing the configuration of the curl state recognition unit. The curl state recognition unit 200 basically includes a distance detection unit 202 having a distance measuring sensor and a distance detection unit moving motor 201. The distance detection unit 202 and the distance detection unit moving motor 201 are mechanically connected by a vertical driving mechanism 208 using timing belts 206 and 207 and can move in the vertical direction along the guide shaft 209. A distance detection unit HP sensor 203 is provided at the home position of the distance detection unit 202. These are mounted on the first base 210 extending in the vertical direction and function as the curl state recognition unit 200. 3 and 4, the paper P or the paper bundle PB is stacked on the internal tray 102. In FIG. 3, the distance detection unit 202 is located at the highest position, and in FIG. 4, the lowest position is shown. Is shown.

  FIG. 5 is an explanatory diagram showing the recognition detection principle of the curled state of the sheet bundle PB loaded on the internal tray 102. FIGS. 6 and 7 are control procedures for recognizing the curled state using the curled state recognition unit 200. FIG. It is a flowchart which shows. This control is executed by the CPU of the stacker 100-1.

  FIG. 8 is a block diagram showing a control configuration of the image forming system in the present embodiment that executes curl state recognition control. The image forming system in this embodiment includes an image forming apparatus PR and a stacker 100-1. The image forming apparatus PR is controlled by an image forming apparatus control unit 410 including a CPU 411, ROM 412, RAM 413, nonvolatile RAM 414, serial I / F 415, timer 416, and the like. The program code for control is stored in the ROM 412, and the CPU 411 expands the program code in the RAM 413, stores data necessary for control in the RAM 413, and uses the RAM as a work area, and the control defined by the program code. Execute.

  The image forming apparatus control unit 410 includes a motor used in the image forming unit 110 such as a photosensitive member, various DC loads 450 such as various motors and clutches in the sheet feeding unit 120, the sheet feeding conveyance path 130, and the double-side conveyance path 170, Various AC loads 470 and various sensors 460 such as a temperature sensor for detecting the temperature of the fixing roller are connected. Further, the image reading device 480 and the operation display unit 440 are connected, and each unit is controlled via the image forming device control unit 410.

  The control of the stacker 100-1 is executed by a sheet processing apparatus control unit 400 including a CPU 401, a ROM 402, a RAM 403, a serial I / F 404, a timer 405, and the like. The program code for control is stored in the ROM 402, and the CPU 401 expands the program code in the RAM 403, stores data necessary for control in the RAM 403, and uses the RAM as a work area, and the control defined by the program code. And various DC loads 420 are controlled. The image forming apparatus PR and the stacker 100-1 exchange commands necessary for paper conveyance control including curl state recognition control via the serial I / Fs 415 and 404, and the stacker 100-1 obtains the commands and various sensors 430. Paper conveyance control and post-processing are performed based on the paper position information or curl state recognition information. The various sensors 430 include the various sensors shown in FIGS.

  As shown in the flowchart of FIG. 6, the curl state recognition control in the first embodiment is performed after paper is discharged to the internal tray 102 (when the internal tray 102 is operating, after the shift operation is completed) (step S101: Yes), FIG. The distance detection unit 202 is lowered from the highest position shown to the lowest position shown in FIG. Then, after the sheet is detected during the descent, the detection distance (the output voltage of the distance measuring sensor 202) continuously increases or decreases as shown in FIGS. 5 (a), 5 (b), and 5 (c). The detection time t is counted (step S102). Then, it is confirmed that the sheet is not folded (step S103), and when the increase / decrease in the detection distance is not continuous within a predetermined time (step S104: Yes), the descent of the distance detection unit 202 is stopped, and the home Return to the position (step S105).

Next, in step S106, it is checked whether or not the detection distance is constantly increasing. This is because the detection distance change pattern is determined by the state of the sheet P or the sheet bundle PB on the internal tray 102 as shown in FIG. That is, as shown in FIG. 5A, the detection distance increases (step S106: Yes), and the detection time tf is equal to or longer than the predetermined time αf (step S107: Yes), that is,
tf ≧ αf
In this case, it is considered that the sheet P1 is abnormal (face curl is large) (step S108). If the paper discharge destination can be changed (step S109: Yes), the paper discharge destination is changed (step S110). If it is not possible, the image forming apparatus PR stops paper discharge after the paper being conveyed (step S111). Note that it is possible to stop paper discharge even if the paper discharge destination can be changed by processing setting when an abnormality occurs in the image forming apparatus PR.

If the detection distance is not increased in step S106 and the detection distance is always decreasing (step S112: Yes), the detection time is checked, and if the detection time tp is equal to or longer than the predetermined time αb (step S113: Yes). ), That is,
tp ≧ αp
In this case, it is considered that the paper P2 is abnormal (the back curl is large) (step S114), and the processing of the above-described steps S109 to S111 is executed. In this case as well, the paper discharge can be stopped even if the paper discharge destination can be changed by the processing setting when an abnormality occurs in the image forming apparatus PR.

If the detection distance is not always decreased in step S112 (step S112: No), the detection time is checked. If the detection time tm is equal to or longer than the predetermined time αm (step S115: Yes), that is,
tm ≧ αm
In this case, it is considered that the paper P3 is abnormal (curled) (step S116), and the processing from step S109 to step S111 described above is executed. In this case as well, the paper discharge can be stopped even if the paper discharge destination can be changed by the processing setting when an abnormality occurs in the image forming apparatus PR.

On the other hand, if the sheet is folded in the determination of step S103, the process proceeds to the flowchart of FIG. 7, and when the decrease in the detection distance is not continuous (step S117: Yes), the distance detection unit 202 is lowered. Stop and return to the home position (step S118). Then, the detection time is checked, and when the detection time tv is not less than the predetermined time αv, that is,
tv ≧ αv
In this case, it is considered that the paper P4 has an abnormality (folding height is high) (step S120), and the processing from step S109 to step S111 described above is executed. Note that it is possible to stop paper discharge even if the paper discharge destination can be changed by processing setting when an abnormality occurs in the image forming apparatus PR.

  In this embodiment, the distance detection unit 202 can be configured to be movable not only in the vertical direction but also in the horizontal direction. 9 and 10 are diagrams showing the configuration of the curl state recognition unit 200 that is also movable in the horizontal direction, and correspond to the views of FIGS. 3 and 4 viewed from the left side. 9 and 10, the curl state recognition unit 200 mounted on the first base 210 shown in FIGS. 3 and 4 is mounted on the second base 220 extending in the horizontal direction integrally with the first base 210. It is mounted on. A horizontal driving mechanism 228 having the same configuration as that of the vertical driving mechanism 218 mounted on the first base 210 on the surface opposite to the mounting side of the first base 210 on the second base 220 is provided. Is provided. A horizontal distance detector HP sensor 225 is provided at the home position of the first base 210, and the moving distance in the horizontal direction is detected based on the home position position.

  The horizontal driving mechanism 228 includes a horizontal movement motor 224, timing belts 226 and 227, an attachment portion 223 attached to the timing belt 227, and a slider 222. The mounting portion 223 protrudes from the back side of the second base 220 in FIGS. 9 and 10 through a horizontally extending groove that is not visible in the drawing, and is fixed to the timing belt 227 on the front side of the second base 220. Yes. Similarly, a slider 222 integral with the first base 210 is slidably mounted in a slide groove 221 formed in parallel with the timing belt 227, and integrated with the first base 210 along at least two horizontal grooves. The slider 222 and the attachment member 223 move.

  When applied to the stacker 100-1 in FIG. 2, the first base 210 reciprocates in the height direction (z direction) of the apparatus, and the second base 220 reciprocates in the depth direction (y direction) of the apparatus. . As a result, the curl state of the paper P can be detected from the left yz plane in the drawing of the internal tray 102. The detection processing procedure of the second base 220 is the same as the processing of the flowcharts of FIGS. 6 and 7 described above except that the detection in the vertical direction is horizontal, and the curl state is also the same as that described in FIG. Is the same.

  When interlocking with the shift operation of the internal tray 102, when the shift direction is changed to the back side, the distance detection unit 202 is returning to the home position where the horizontal distance detection unit HP sensor 225 is installed, or After returning, as shown in FIG. 10, the distance detection unit 202 is horizontally moved to the back side detection position of the stacker 100-1. When the shift direction is changed to the near side, the distance detection unit 202 is moved to the near position (home position position) as shown in FIG. 9 during or after the distance detection unit 202 returns to the home position. Move horizontally.

  Here, the vertical direction driving mechanism 218 and the horizontal direction driving mechanism 228 are mounted on the same apparatus so as to be able to scan the same plane, but the driving mechanism is independently applied to different planes. 218 and 228 can also be provided.

  FIG. 11 is a flowchart showing a control procedure of curl state recognition control when the shift position is changed. In the figure, first, the presence / absence of a shift position change is checked (step S201). If there is a position change, the shift direction is checked (step S202). If it is the front side, the distance detection unit 202 is horizontally moved to the front detection position (step S204).

  FIG. 12 is an explanatory diagram illustrating the curl state recognition detection principle by installing the curl state recognition unit 200 downward on the side plate 100c on the inner upper side of the stacker 100-1. 4A shows a case where the face curl is large (paper P1), FIG. 4B shows a state where the back curl is large (paper P2), and FIG. 3C shows a state where the curl is generated (paper P3). (D) shows a state in which the folding height is large (paper P4). The CPU 401 of the paper processing device control unit 400 determines the state of the paper P based on the detection result from the distance detection unit 202. This detection procedure is in accordance with the flowcharts of FIGS. As described above, the vertical direction detection in FIGS. 3 and 4 and the horizontal direction detection in FIGS. 9 and 10 can be combined to detect the curl state of the paper on the yz plane. However, the sheet can be moved in the x and y directions. It is also possible to detect curl in the xy plane using two bases.

  When detecting the curl amounts at the two corners of the paper, it is possible to set which position of the central portion or the two corners of the paper is measured from the operation display unit 440 of the image forming apparatus PR. That is, a mode for measuring two corners can be set from the operation display unit 440 of the image forming apparatus PR. FIG. 13 is a flowchart showing a control procedure of curl state recognition control when a mode for measuring two corners of a sheet is set. In this figure, since the user has already set the paper two-corner measurement (step S301: Yes), before the paper is discharged, the distance detection unit 202 is horizontally moved to the back side (step S302: FIG. 10). . The movement time is a time βNSB seconds set in advance according to the position (N) before movement, the paper size (S), and the movement direction (B). At this time, the distance detection unit 202 is in the initial state, that is, the state shown in FIG. 3, and the initial position is the uppermost position on the back side.

  Next, after the paper is discharged to the internal tray 102 (when the internal tray 102 is operating, after the shift operation is completed), the distance detection unit 202 is lowered from the state of FIG. 3 to the state of FIG. 4 (step S303). After the sheet is detected during the descent, the detection time t is counted while the detection distance (the output voltage of the distance measuring sensor) increases or decreases continuously as shown in FIGS. When the increase or decrease in the detection distance is not continuous within a predetermined time, the descent of the distance detection unit 202 is stopped. After the stop, the distance detection unit 202 is horizontally moved to the near side (step S303: FIG. 9). The movement time is a time βNSF seconds set in advance according to the position (N) before movement, the paper size (S), and the movement direction (F).

  Thereafter, as shown in FIGS. 4 and 3, the distance detection unit 202 is raised (step S305), and the reverse operation to step S303 is performed. That is, the detection time t is counted while the detection distance continuously increases or decreases as shown in FIGS. 5A to 5C after the sheet is detected during the rise, and the detection distance is within a predetermined time. When the increase / decrease is not continuous, the elevation of the distance detection unit 202 is stopped. Thereby, although it is not planar, it can grasp | ascertain reliably the curl state of a back side and a near side.

  On the other hand, if the paper two-corner measurement is not set in step S301, it is confirmed whether or not the distance detection unit 202 is in the center on the back side and the near side (step S306). Then, the sheet is horizontally moved to one end of the sheet (step S307). The movement time is a time βNSM seconds set in advance according to the position (N) before the movement, the paper size (S), and the movement direction (M). The moving direction is set in advance on the back side or the near side. Next, the distance detection unit is lowered and the same operation as in step S303 is performed (step S308). Thereby, it is possible to recognize the curled state of the paper edge on the back side or the near side.

  FIG. 14 is a schematic configuration diagram illustrating an outline of the entire stacker as a sheet processing apparatus according to the second embodiment. A stacker 100-2 according to the second embodiment is obtained by replacing the internal tray 102 according to the first embodiment with a fixed internal tray 102a. Since the sheets P are stacked from the bottom of the internal tray 102a, the alignment operation by the main jogger pair 150 and the sub jogger pair 151 is impossible, so both jogger pairs are omitted.

  FIG. 15 is a perspective view showing an overall configuration of a fixed internal tray 102a according to the second embodiment. In the case of the second embodiment, a rectangular opening 102c is provided on the side surface 102b of the internal tray 102a so that the stacked state of the sheets P inside the tray can be seen. Therefore, in order to recognize the state of the paper P, as shown in FIG. 14, when the inner tray 102a is set at the paper stacking position, on the inner side surface of the stacker 100-2 facing the opening 102c, the opening 102c The curl state recognition unit 200 shown in FIGS. 3 and 4 in the first embodiment is installed with the distance measuring unit 202 facing. Thereby, the distance detection unit 202 can recognize the curled state of the paper in the internal tray 102a through the opening 102c. The distance detection unit 202 detects the distance of the edge of the paper P while moving upward from the lowest position shown in FIG. The detection principle, operation and control are the same as in the first embodiment.

  In the case of the second embodiment, the central portion on the rear side and the front side of the apparatus is shown, but the curled state of the paper P can be recognized at this position as in the first embodiment. Note that if the scanning start position of the distance measuring unit 202 is set to the lowest position described above, it is only necessary to sequentially scan the sheets discharged from the top, and the detection time can be shortened. In addition, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. Other parts not specifically described are configured in the same manner as in the first embodiment and function in the same manner.

  FIG. 16 is a schematic configuration diagram illustrating an overall outline of a sheet post-processing apparatus as a sheet processing apparatus according to the third embodiment. The sheet post-processing apparatus 300 has a plurality of post-processing functions such as a shift function, a punch function, an alignment function, an end binding function, a saddle stitching / center folding function, and the paper discharge unit 312 provides a shift function and a punch unit 307. The punching function is realized by the jogger 313, the end binding function is realized by the end face binding stapler 310, and the saddle stitching and center folding functions are realized by the saddle stitching stapler 311, the folding plate 308 and the folding roller pair 309.

  That is, the paper carried in from the paper carry-in entrance 314 is conveyed by the entrance roller 319, and when punch punching processing is performed, punch punching processing is performed by the punch unit 307. Conveyed to the side. The transported paper is selected in three directions by switching the positions of the switching claws 305 and 306 according to the paper processing. When paper is discharged without any processing, the upper transport path is selected and discharged to the proof tray 301. In the case of shifting, the central conveyance path is selected, and the paper discharge unit 312 moves the copy one by one in the direction orthogonal to the paper conveyance direction to perform a shift operation for distinguishing the units, and the external paper discharge tray. The paper is discharged to 302.

  When aligning a bundle of sheets, the lower conveyance path is selected, discharged to the staple tray 313, the sheet conveyance direction is set by the rear end reference fence 314, and the direction orthogonal to the sheet conveyance direction is set by the jogger fence 315. Each aligned sheet bundle is lifted by the discharge claw and discharged from the sheet discharge unit 312 to the external sheet discharge tray 302. When performing edge binding, a predetermined portion of the end face of the sheet bundle is bound to the sheet bundle aligned on the staple tray 313 by the end face binding stapler 310, and the sheet is discharged to the external discharge tray 302 in the same manner. When performing saddle stitching or folding, the sheet bundle aligned on the staple tray 313 is lifted by the discharge claw, and the center position of the sheet bundle in the conveyance direction is made to coincide with the binding position of the saddle stitching stapler 311, Then, a predetermined portion (usually two locations) is bound by the saddle stitching stapler 311. After that, it is turned along the roller guide 316 and guided to the half-fold tray 317. In the middle folding tray 317, the folding position is adjusted to the folding plate 308 position by the movable rear end fence 318, the folding plate 308 is pushed out to the sheet bundle side and pushed into the nip of the folding roller pair 309, and the folding roller pair 309 performs the middle folding. . The folded sheet bundle is discharged to a lower tray (folding tray) 304 by a discharge roller pair 319.

  In this embodiment, the curl state recognition unit 200 is placed on the inner side of the side surface 320 of the sheet post-processing apparatus 300 on the side facing the sheet discharge surface 302 a of the external sheet discharge tray 302. Provided. The curl state recognition unit 200 is installed so that the distance measuring unit 202 faces the paper discharge surface 302a of the external paper discharge tray 302, and recognizes the curl state of the paper P stacked on the paper discharge surface 302a. The configuration of the curl state recognition unit 200 is the same as that shown in FIGS. 3 and 4 in the first embodiment, and the configuration shown in FIGS. 9 and 10 can be added. Thereby, the curl state recognition control can be executed in the same procedure as the flowcharts of FIGS. 6, 7, 11, and 13 in the first embodiment, and the curl state can be recognized based on the principle shown in FIG.

As described above, according to the present embodiment,
1) Since the curl state recognition unit 200 that is movable in the vertical direction and / or the horizontal direction is provided, the paper size, the presence / absence of paper shift, and the presence / absence of raising / lowering of the discharge tray (internal trays 102, 102a, external tray 302) Regardless of this, it is possible to detect the curl height, direction, curl, or folding height of the paper on the paper discharge tray. At this time, the detection can be performed in a planar manner by moving in the vertical direction and the horizontal direction in parallel. It can also be detected at a specific position on the paper.
2) By arranging the necessary positions and numbers according to the curl direction peculiar to the image forming apparatus PR, it is possible to detect the curl of the paper in all directions.
3) If the curl is excessive, rounding occurs and it is determined that an abnormality has occurred. If an abnormality occurs, the paper can be discharged to another discharge tray in the post-processing device or downstream post-processing device. If the paper discharge is continued, the paper discharge is stopped, so that the paper discard due to the occurrence of a paper jam or the like is reduced, and the resource can be saved.
4) Since paper discharge is continued until the paper being conveyed in the image forming apparatus PR at the time of occurrence of the abnormality, paper removal work in the image forming apparatus PR when the abnormality is stopped immediately can be omitted, and resource saving It becomes possible.
5) When control is performed so that the height from the paper discharge section to the uppermost sheet on the discharge tray is constant, detection starts from the top of the stacked paper, reducing the detection time and reducing power consumption. It becomes possible.
6) When the paper discharge tray is fixed, the detection time can be shortened by starting detection from the bottom of the stacked paper, and power can be saved.
There are effects such as.

100-1, 100-2 Stacker 102, 102a Internal tray 202 Distance detection unit 208 Vertical direction driving mechanism 228 Horizontal direction moving mechanism 300 Paper post-processing device 302 External tray 401 CPU
P sheet P1 face curl sheet P2 back curl sheet P3 curled sheet P4 folded sheet PB sheet bundle PR image forming apparatus

JP 2003-026370 A

Claims (11)

A stacking means for stacking the conveyed paper;
A distance detecting means for detecting a distance to a sheet or sheet bundle stacked on the stacking means;
Moving means for moving the distance detecting means relative to the paper or paper bundle;
Paper state recognition means for recognizing the deformation state of the paper based on the change state of the distance continuously detected by the distance detection means while being moved by the movement means;
A paper processing apparatus. The sheet processing apparatus according to claim 1,
The sheet processing apparatus, wherein the moving unit moves the distance detecting unit in a direction perpendicular to a sheet stacking surface of the stacking unit and scans an end surface of the sheet. The sheet processing apparatus according to claim 2,
The sheet processing apparatus, wherein the moving unit moves the distance detecting unit in a direction parallel to the end surface of the sheet of the stacking unit, and scans the end surface of the sheet. The sheet processing apparatus according to claim 1,
The moving means moves the distance detecting means along the upper surface of the sheet or sheet bundle in the main scanning direction and / or the sub-scanning direction with respect to the sheet conveying direction, and scans the upper surface of the sheet or sheet bundle. A paper processing apparatus. The sheet processing apparatus according to claim 1,
The sheet processing apparatus according to claim 1, wherein the distance detecting unit is provided at one or more of a front surface, a rear surface, and a side surface in the sheet conveyance direction. The sheet processing apparatus according to any one of claims 1 to 5,
A sheet processing apparatus, comprising: a control unit that changes a conveyance destination of the sheet or stops conveyance when the sheet state recognition unit recognizes that the deformation state of the sheet is abnormal. The sheet processing apparatus according to claim 6,
The paper processing apparatus, wherein when the paper state recognizing means recognizes that the deformation state of the paper is abnormal, the control means continues to carry the paper being conveyed in the previous stage from the previous stage. A sheet processing apparatus according to any one of claims 1 to 7,
The sheet processing apparatus according to claim 1, wherein the abnormality is an abnormality in a deformation state of the sheet including one of a face curl, a back curl, a rounding, and a folding height. The sheet processing apparatus according to claim 1 or 2,
The paper processing device, wherein the paper state recognition unit starts the movement of the distance detection unit from above when the stacking unit can be moved up and down. The sheet processing apparatus according to claim 1 or 2,
The sheet processing device, wherein the sheet state recognition unit starts the movement of the distance detection unit from below when the stacking unit cannot be moved up and down. A sheet processing apparatus according to any one of claims 1 to 10,
An image forming apparatus for forming an image on paper;
An image forming system comprising:

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