JP5165036B2 - Sheet processing apparatus, image forming apparatus, and image forming system - Google Patents

Description

  The present invention relates to a sheet processing apparatus, an image forming apparatus, and an image forming system, and more particularly to a configuration for folding and binding a sheet bundle.

  2. Description of the Related Art Conventionally, there is an image forming apparatus represented by a digital copying machine, which has a scan function for reading an image from a document and a print function for printing the scan image on a sheet such as recording paper. In such an image forming apparatus, after an image is formed, a sheet to be discharged is taken in, and the sheet is subjected to binding processing near the center of the sheet, and is subjected to processing such as folding in half. Some have a sheet processing apparatus for discharging and stacking on a sheet stacking unit.

  By the way, as an example of such a sheet processing apparatus, there is a space-saving, small and low cost saddle stitch bookbinding apparatus. Here, in such a saddle stitch binding apparatus, after the sheets conveyed one by one are stacked and aligned on a substantially vertical vertical intermediate stacking tray, the center of the sheet is saddle stitched by a stapler, and then the veneer plate Binding is performed by folding the center of the sheet with a folding roller.

  In such a conventional saddle stitch bookbinding apparatus, when a sheet is carried into the intermediate stacking tray, a leading end regulating member that abuts on the leading end portion of the sheet and aligns the sheet is provided. Note that the position of the leading end regulating member is set to a position where the central portion in the conveyance direction can be bound and a position where it can be bent at the binding position according to the size of the sheet that has been carried in.

  In addition, when the binding position and the folding position are deviated from the center due to variations in sheet size, there is a configuration in which the user can adjust the sheet height at the time of binding and folding (for example, Patent Document 1). reference.).

JP 2001-206626 A

  Here, in such a conventional sheet processing apparatus (saddle stitch bookbinding apparatus), the folding process is performed by always projecting the central portion of the sheet with the thrust plate regardless of the size, thickness, and number of bundles of the sheets. Yes. However, when the central portion of the sheet is pierced by the thrust plate in this way, especially when the intermediate stacking tray is arranged substantially vertically, the folding position changes depending on the weight and rigidity of the sheet, and the folding position of the sheet is shifted. There was a problem that.

  Next, the mechanism of such folding position shift will be described with reference to FIG.

  In FIG. 8A, the sheet S is carried into the intermediate stacking tray 412 arranged substantially vertically, aligned and saddle-stitched, and thereafter, until the sheet is folded to the middle folding position where the lower end of the sheet contacts the leading edge regulating member 411. A state immediately before the bundle folding operation after the bundle is conveyed is shown.

  In this state, when the sheet bundle Sa is struck by the pushing plate 418, in the case of the substantially vertical intermediate stacking tray 412, the pushing plate 418 and the sheet S are kept until the folded portion of the sheet bundle Sa enters the nip of the folding roller 413. The lower end of the sheet bundle Sa is lifted by the frictional force.

  FIG. 8B shows a state in which a small number of, for example, two sheet bundles Sa are struck, and a sheet bundle is struck by projecting the center of the sheet bundle Sa in the conveying direction at the tip of the pushing plate 418. Sa is in a state where the lower end is lifted from the tip regulating member 411. In this state, the folded portion of the sheet bundle Sa is guided to the nip of the folding roller 413.

  On the other hand, FIG. 8C shows a state when a sheet bundle Sa in which a large number of sheets, for example, 20 sheets S are bound, is struck. In this case, only the abutting plate 418 is caused by the weight of the sheet bundle Sa. Thus, the sheet bundle Sa cannot be moved into the folding roller 413 while being lifted. In such a case, as a result, the sheet bundle Sa is folded halfway at a position shifted upward from the center position of the sheet bundle Sa.

  Further, when the path shape above the folding position of the intermediate stacking tray 412 is a curved path due to the configuration of the apparatus as shown in FIG. The sheet S cannot be lowered due to the influence of the conveyance resistance of the curved path. As a result, the sheet bundle Sa is folded halfway at a position shifted downward from the center position of the sheet bundle Sa.

  Note that the influence of the curved path varies depending on the stiffness of the sheet S, that is, the thickness and size, and thus the amount of deviation depends on the sheet thickness and size. Furthermore, the folding position shift caused by the number of sheets, the size, and the thickness of the sheet is affected by the coefficient of friction between the tip (sheet contact portion) of the abutting plate 418 and the sheet S. The state (presence / absence of an image) is also a factor of the folding position shift.

  FIG. 9 shows the state of the booklet B when the folding position shift occurs due to the above-described factors. Even when the saddle stitching position is at the regular position, the folding position is shifted by the distance L. On the open end face of the booklet B, a shift of 2L occurs, which makes the appearance worse.

  Conventionally, when a deviation occurs in the produced booklet booklet B, the user measures the distance L and adjusts the saddle stitching position or the middle folding position. In addition, there is a problem that the adjustment is necessary for each job type, which is complicated.

  Accordingly, the present invention has been made in view of such a current situation, and an object of the present invention is to provide a sheet processing apparatus, an image forming apparatus, and an image forming system capable of binding a good-looking sheet bundle. Is.

The present invention, sea in processing sheet processing apparatus for performing folding the sheet bundle at a predetermined folding position, the sheet stacking portion for stacking in a standing state the sheet bundle, the sheet bundle stacked on the sheet stacking portion lower end those to support the sheet bundle in contact, said a sheet stacking portion direction movable sheet bundle to a support along the member, and the sheet bundle of the sheet bundle supported by the support member in fold folding roller pair, the sheet bundle A projecting unit that abuts against the sheet bundle supported by the support member and pushes the sheet bundle into a nip of the folding roller pair while folding the sheet bundle; and moves the sheet bundle support member, and a control means for controlling the position of the sheet bundle abuts against the said control means, the sheet at a position where the protruding section abuts against the sheet bundle In the projecting means for producing in response to the surface smoothness of shift amount of the bending positions of the previous Kisho constant impinging the sheet bundle, the protruding means abuts against the sheet bundle Rashi not from the predetermined bending position Thus, the sheet bundle supporting member is controlled to move .

  According to the present invention, when a sheet bundle is folded, the folding position of the sheet bundle can be made coincident with a desired folding position of the sheet bundle, so that a good-looking sheet bundle can be bound.

1 is a cross-sectional view of an image forming system according to an embodiment of the present invention. Sectional drawing of the finisher which is the said sheet processing apparatus. The figure which shows the sheet | seat bundle bending operation | movement of the said finisher. The figure which shows the operation | movement which bends the light sheet bundle of the said finisher. The figure which shows the operation | movement which bends the heavy sheet | seat bundle | flux of the said finisher. The system block diagram which shows the system of the copying machine main body and finisher of the said copying machine. The figure which shows the operation | movement which bends the sheet | seat bundle | flux where the upper part of the said finisher got caught. The figure explaining the mechanism of folding position shift. The figure which shows the state of a booklet booklet when the above-mentioned folding position shift has occurred.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view of an image forming system according to an embodiment of the present invention. The image forming system includes a sheet processing apparatus and a copying machine that is an example of an image forming apparatus connected to the sheet processing apparatus.

  In FIG. 1, reference numeral 1000 denotes a copying machine. The copying machine 1000 includes a copying machine main body 300 and a scanner 200 disposed on the upper surface of the copying machine main body 300.

  Here, the scanner 200 for reading a document includes a document feeding unit 100, a scanner unit 104, a lens 108, an image sensor 109, and the like. When reading the document D by the scanner 200, first, the document D is set on the tray 100 a of the document feeding unit 100. At this time, it is assumed that the document D is set with the face on which the image is formed on the tray 100a facing upward.

  Next, after the originals D set in this way are conveyed one by one from the top page in order to the left (in the direction of the arrow in the figure) by the original feeding unit 100, the left side of the platen glass 102 is left on the curved path. The paper is conveyed from the right direction to the right direction, and then discharged onto the paper discharge tray 112.

  At this time, when reading the original by so-called flow reading, the scanner unit 104 is held in a predetermined position, and the original D passes through the scanner unit 104 from left to right. The reading process is performed.

  In this reading process, when passing through the platen glass 102, the document D is irradiated with light from the lamp 103 of the scanner unit 104, and the reflected light is imaged through the mirrors 105, 106, 107 and the lens 108. Lead to 109. The document image data read by the image sensor 109 is subjected to predetermined image processing and sent to the exposure control unit 110.

  On the other hand, when reading a document by so-called fixed reading, the document D conveyed by the document feeding unit 100 is temporarily stopped on the platen glass 102, and the scanner unit 104 is moved from left to right in this state, thereby the document. The reading process is performed. Further, when reading a document without using the document feeding unit 100, the user lifts the document feeding unit 100 and sets the document on the platen glass 102.

  Further, the copying machine main body 300 includes a sheet feeding unit 1002 that feeds sheets S stored in the cassettes 114 and 115, and an image forming unit 1003 that forms an image on the sheet S fed by the sheet feeding unit 1002. Etc.

  Here, the image forming unit 1003 includes a photosensitive drum 111, a developing unit 113, a transfer charger 116, and the like, and laser light from the exposure control unit 110 is irradiated onto the photosensitive drum during image formation. Thus, a latent image is formed on the photosensitive drum, and this latent image is visualized as a toner image by the developing device 113 thereafter. A fixing device 117, a discharge roller pair 118, and the like are disposed on the downstream side of the image forming unit 1003.

  Next, an image forming operation of the copying machine main body 300 having such a configuration will be described.

  First, as described above, the image data of the document D read by the image sensor 109 in the flow reading or fixed reading in the scanner 200 is sent to the exposure control unit 110 after being subjected to predetermined image processing. It is done. Then, the exposure control unit 110 outputs a laser beam corresponding to the image signal.

  The laser beam is irradiated onto the photosensitive drum 111 while being scanned by the polygon mirror 110a, and an electrostatic latent image corresponding to the scanned laser beam is formed on the photosensitive drum 111. Next, the electrostatic latent image formed on the photosensitive drum 111 is developed by the developing device 113 and visualized as a toner image.

  On the other hand, the sheet S is conveyed from any of the cassettes 114 and 115, the manual sheet feeding unit 125, and the double-sided conveyance path 124 to a transfer unit including the photosensitive drum 111 and the transfer charger 116. Then, the toner image on the photosensitive drum visualized in the transfer unit is transferred to the sheet S, and the fixing unit 117 performs a fixing process on the sheet S after the transfer.

  Next, the sheet S that has passed through the fixing unit 117 is once guided to the path 122 by the flapper 121. After the trailing edge of the sheet passes through the flapper 121, the sheet S is switched back and conveyed to the discharge roller 118 by the flapper 121. Drain from 300. Thus, the sheet S can be discharged from the copying machine main body 300 with the surface on which the toner image is formed facing down (face down).

  In addition, when the image forming process is performed in order from the first page by discharging the sheet S face down by the so-called reverse sheet discharging, for example, when the image forming process is performed using the document feeding unit 100. The page order can be aligned. Further, the page order can be aligned when image forming processing is performed on image data from a computer.

  When image forming processing is performed on a hard sheet S such as an OHP sheet conveyed from the manual sheet feeder 125, the sheet S is discharged without being guided to the path 122. As a result, the surface on which the toner image is formed is discharged from the copying machine main body 300 by the discharge roller 118 in an upward state (face up).

  When image forming processing is performed on both sides of the sheet S, the sheet S is guided straight from the fixing unit 117 toward the discharge roller, and the sheet S is switched back immediately after the trailing edge of the sheet S passes through the flapper 121. The flapper 121 guides to the double-sided conveyance path 124.

  By the way, the copying machine main body 300 includes a folding processing unit 400 that performs a folding process on an image-formed sheet discharged from the copying machine main body 300 and a finisher 500 that is a sheet processing apparatus that performs binding processing and bookbinding processing on the sheet. Is provided.

  Next, the configuration of the folding processing unit 400 and the finisher 500 will be described.

  As shown in FIG. 1, the folding processing unit 400 includes a conveyance path 131 for introducing the sheet discharged from the copying machine main body 300 and guiding the sheet to the finisher 500 side. Pairs 130 and 133 are provided. Further, a switching flapper 135 is provided in the vicinity of the conveying roller pair 133, and this switching flapper 135 is for guiding the sheet conveyed by the conveying roller pair 130 to the folding path 136 or the finisher 500 side.

  Here, when the folding process is performed on the sheet S, the switching flapper 135 is switched to the folding path 136 side and the sheet is guided to the folding path 136. Thereafter, the leading edge of the sheet guided to the folding path 136 is abutted against the stopper 137, and the loop formed gradually by the abutting of the leading edge in this way is folded by the folding rollers 140 and 141. Furthermore, the sheet is Z-folded by further folding the loop formed by abutting the bent portion against the upper stopper 143 by the folding rollers 141 and 142.

  The Z-folded sheet is sent to the conveyance path 131 through the conveyance path 145 and discharged to the downstream finisher 500 by the discharge roller 133. On the other hand, when the folding process is not performed, the switching flapper 135 is switched to the finisher side, and the sheet discharged from the copying machine main body 300 is directly fed to the finisher 500 via the conveyance path 131.

  On the other hand, the finisher 500 performs processing for fetching sheets from the copying machine main body 300, aligning a plurality of fetched sheets and binding them as one sheet bundle, sorting processing, and non-sorting processing. In addition, other processes such as a stapling process (binding process) for stapling the rear end side of the sheet bundle, a bookbinding process, and the like are performed. A saddle stitch portion 800 is provided.

  Further, as shown in FIG. 2, the finisher 500 includes an inlet roller pair 232 for taking a sheet conveyed via the folding processing unit 400 into the apparatus. Further, a switching flapper 235 for guiding the sheet to the finisher path P1 or the lower bookbinding path 234 is provided downstream of the inlet roller pair 232.

  For example, when the sheet S is guided to the finisher path P1 by the switching flapper 235, the sheet is conveyed toward the buffer roller 513 via the conveying roller pair 510. A punch unit 512 is provided between the conveying roller pair 510 and the buffer roller 513. By operating the punch unit 512 as necessary, a punching process is performed near the rear end of the sheet conveyed via the conveying roller pair 510.

  The buffer roller 513 is a roller capable of winding a predetermined number of sheets conveyed via the conveying roller 510, and the sheet is wound by a pressing roller 515 while the buffer roller 513 is rotating. As a result, the sheet is conveyed in the direction in which the buffer roller 513 rotates.

  Further, a buffer path 516 is formed on the peripheral surface portion of the buffer roller 513, a switching flapper 517 is provided in the middle of the buffer path 516, and a switching flapper 520 is further provided therebelow.

  Here, the switching flapper 517 is for separating the sheet wound around the buffer roller 513 from the buffer roller 513 and leading the sheet to the non-sort path 530 or the sort path 521 on the sample tray 701 side. Note that the sheet guided to the non-sort path 530 by the switching flapper 517 is discharged onto the sample tray 701 via the discharge roller pair 519.

  The switching flapper 520 is also for separating the sheet wound around the buffer roller 513 from the buffer roller 513 and guiding it to the sort path 521, or for guiding it to the buffer path 516 while being wound around the buffer roller 513. .

  Then, the sheet guided to the sort path 521 by the switching flapper 520 is stacked on a processing tray 630 serving as an intermediate tray via a pair of conveying rollers 522 and 523. The group of sheets stacked on the processing tray 630 is subjected to alignment processing and stapling processing according to settings from an operation unit shown in FIG. 6 to be described later, and then stacked by discharge rollers 610a and 610b. It is discharged onto the tray 700. Note that the stapling process is performed by a stapler 601 configured to be capable of self-propelling in the vertical direction.

  On the other hand, when the sheet is guided to the bookbinding path 234 by the switching flapper 235, the sheet is selected by the flapper 236 according to the size, and the sheet is loaded on the intermediate stacking tray 2 which is the sheet stacking unit of the saddle stitch unit 800. It is brought in.

  Here, the saddle stitch unit 800 includes an inclined or substantially vertical intermediate stacking tray 2 for storing the sheet bundle Sa in an upright state. Further, a stapling portion 7A is provided at the upper end portion of the intermediate stacking tray 2 and includes two pairs of staplers 7 and an anvil (not shown) that binds the center of the sheet bundle in cooperation with the stapler 7. . Furthermore, a folding roller pair 3 provided on the downstream side of the stapler 7 and a pushing plate 8 which is a protruding means provided facing the folding roller pair 3 are provided. In addition, a movable front end regulating member 1 that is a sheet bundle supporting member that contacts the front end (lower end) of the sheet bundle Sa to support the sheet bundle and regulates the front end position of the sheet bundle is provided.

  As shown in FIG. 3, the thrust plate 8 is projected toward the sheet bundle Sa stored in the intermediate stacking tray 2 by the link unit 10 and the driving unit 9. Further, the tip regulating member 1 is fixed to a belt 11 driven by driving means 12 such as a motor, and is moved up and down via the belt 11 by forward / reverse rotation of the driving means 12.

  Next, the bookbinding operation of the saddle stitch unit 800 having such a configuration will be described.

  First, the sheet carried into the intermediate stacking tray 2 of the saddle stitch unit 800 is conveyed until the leading edge comes into contact with the leading edge regulating member 1 that is previously positioned at a predetermined binding processing position, and is in a direction orthogonal to the conveying direction. Alignment in the width direction is performed. Thereafter, when the binding process is set, the center is bound by the staple unit 7A in this state.

  Next, the sheet bundle whose center is bound by the staple unit 7A in this way is folded halfway when the leading end regulating member 1 is lowered to the position shown in FIG. Move to position. Note that the saddle stitch portion 800 is provided with a tip regulating home position sensor 13 for detecting the position of the tip regulating member 1 shown in FIG. The leading edge regulating member 1 changes the moving distance from the home position according to the size of the sheet based on the signal from the leading edge regulating home position sensor 13. As a result, it is possible to perform saddle stitching at the center of the sheet and move to a position where it can be folded at the center.

  Next, in this state, the pushing plate 8 is pushed out by the link means 10 and the driving means 9 toward the sheet bundle Sa stored in the intermediate stacking tray 2 as shown in FIG. ) And push into the nip of the folding roller pair 3 as shown in FIG. As a result, the sheet bundle Sa is folded by the pair of folding rollers 3 as shown in FIG.

  After the sheet bundle Sa is bent, the thrust plate 8 is moved away from the folding roller pair 3 by the link means 10. Further, the sheet bundle Sa folded in this way is discharged to the discharge tray 246 while being guided by the guide plate 247 via the pair of folding rollers 3 and the discharge roller 245 shown in FIG.

4A shows the sheet bundle Sa when the sheet has a normal thickness (for example, 80 g / m ² sheets) and the number of bundles is small (for example, 5 sheets or less), that is, when the sheet bundle Sa is light. The folding set position is shown. When the sheet bundle Sa is light in this way, the leading edge regulating member 1 is lowered to a position where the stapling position is at a height that substantially coincides with the leading edge position of the thrust plate 8. That is, when the sheet bundle Sa is light, the front end regulating member 1 is moved to a position where the front end position of the thrust plate 8 and the stapling position which is a desired folding position coincide.

  Then, the front end regulating member 1 is moved to such a position, the sheet bundle Sa is set at a height where the stapling position coincides with the front end position of the veneer plate 8, and is made to protrude by the veneer plate 8. As a result, the paper bundle Sa having a light weight and a weak stiffness, as shown in FIG. 4B, keeps the height of the stapling position while separating the lower end from the front end regulating member 1, in other words, the lower end. Is guided to the folding roller pair 3 while being lifted.

On the other hand, FIG. 5A shows a case where the sheet has a normal thickness (for example, 80 g / m ² paper) and the number of bundles is large (for example, 15 sheets or more). The folding setting position of the sheet bundle Sa when the lower end cannot be lifted even when the operation is performed is shown.

  When the sheet bundle Sa is heavy as described above, the leading edge regulating member 1 has a higher stapling position than the leading edge position of the abutting plate 8, that is, higher than the position of the leading edge regulating member 1 in the case of FIG. Lower to position. That is, when the sheet bundle Sa is heavy, the leading edge regulating member 1 is moved to a position where the stapling position is higher than the leading edge position of the thrust plate 8 by a predetermined amount.

  The difference in height between the stapling position and the tip position of the pushing plate 8 depends on the position of the pushing plate 8 against the sheet bundle Sa according to the weight of the sheet bundle Sa, the folding position where the folding roller pair 3 is bent, and This corresponds to the amount of deviation. Obtained by the weight of the sheet bundle Sa, which is an example of the sheet bundle information, and a deviation amount between a position where the pushing plate 8 first strikes the sheet bundle Sa and a desired folding position where the folding roller pair 3 is folded, The abutting plate 8 abuts against the sheet bundle Sa deviating from the desired folding position.

  In this way, the tip regulating member 1 moves. In this embodiment, the amount of deviation is obtained in advance by experiments or the like and stored in the memory. Based on the information on the sheet bundle, the leading end regulating member 1 is moved so that the pushing plate 8 is pushed against the sheet bundle Sa by a deviation amount stored in the memory from the desired folding position.

  Here, when the leading end regulating member 1 is moved to such a position, the sheet bundle Sa is set at a position where the stapling position is higher than the leading end position of the thrust plate 8 by a predetermined amount, and as a result, the sheet against which the thrust plate 8 abuts. The position of the bundle Sa is lower than the staple position of the sheet bundle Sa.

  When the pushing operation by the pushing plate 8 is started in a state where the sheet bundle Sa is set at such a position, the initial pushing position where the pushing plate 8 hits the sheet bundle Sa is below the staple position. However, as the pushing operation proceeds, the leading end of the pushing plate slides on the sheet surface due to the weight of the sheet bundle Sa and approaches the stapling position, and the sheet bundle Sa eventually enters the nip of the folding roller pair 3. As a result, the protruding position and the staple position coincide with each other.

  As described above, when the weight of the sheet bundle Sa is heavy, the position of the leading end regulating member 1 is set to a position where the abutting position of the abutting plate 8 is lower than the staple position. As shown, it cannot rise even in a state where it is struck by the veneer 8 and bent in the shape of "<". For this reason, even when the sheet bundle Sa is in a state where the lower end is in contact with the leading end regulating member 1, the staple position is guided to the pair of folding rollers 3 when being folded.

  When the number of sheet bundles is determined by reading the original document and the value is equal to or greater than the predetermined number, the folding position is controlled by controlling the height of the leading edge regulating member 1 at the time of folding as described above. The deviation can be eliminated.

  4 and 5 show the difference in the stop position of the leading end regulating member 1 due to the difference in the number of bundles. This phenomenon is not limited to the difference in the number of sheets, the difference in sheet thickness and size, and the vicinity of the protrusion position. It also occurs depending on the state of the sheet surface.

For example, even when the number of sheet bundles is a small number, when folding thick paper of 250 g / m ² or more, the lower end of the sheet bundle Sa may not be raised at the time of pushing, as in the case of folding many sheets. Therefore, when the thick paper mode using thick paper is set, the folding position shift can be eliminated by performing a control for increasing the height of the leading end regulating member 1 at the time of folding.

  Even when the number of sheet bundles is a small number, when folding coated paper having a smooth surface coated, the lower end of the sheet bundle Sa may not be raised at the time of pushing, as in the case of folding many sheets. Therefore, when the coated paper mode using the coated paper is set, the folding position deviation can be eliminated by performing control to increase the height of the leading end regulating member 1 at the time of folding. it can.

  That is, the position of the leading end regulating member 1 is controlled according to the type of sheet. Specifically, the sheet is disposed so that the abutting plate 8 abuts against the sheet bundle Sa by a deviation amount between the position where the abutting plate 8 first abuts against the sheet bundle Sa and the folding position where the abutting plate 8 is folded by the folding roller pair 3. The position of the tip restricting member 1 is controlled in accordance with the type.

  Furthermore, it goes without saying that the setting of the amount of shift of the leading end regulating member 1 from the normal position is different when the sheet size is different even when the same thick paper or multiple sheets are set. When the sheet size is small, the front end regulating member 1 is set to a position where the stapling position is at a height that substantially coincides with the front end position of the veneer plate 8. When the sheet size is large, control is performed to increase the height of the leading end regulating member 1 at the time of folding.

  Further, for example, when there is a color image at a portion where the veneer 8 abuts, the sheet and the veneer tip are easily slipped and the same phenomenon occurs. Therefore, the same control is effective even when the color mode is selected.

  If there is a black and white image at the portion where the veneer 8 abuts, the tip restricting member 1 is set to a position where the stapling position is substantially the same as the tip position of the veneer 8. When there is a color image at a portion where the veneer 8 abuts, control is performed to increase the height of the tip regulating member 1 at the time of folding. In this case, the image forming unit 1003 recognizes the presence / absence of an image at the center of the sheet and feeds it back to the finisher 500, thereby reducing the folding position deviation.

  As described above, in the present embodiment, the position of the front end regulating member 1 is determined based on the number of sheet bundles, the type of sheet bundle, the size of the sheet bundle, and the information on the sheet bundle exemplified as an image formed on the sheet. Control. The position of the leading edge regulating member 1 is a position shifted from the folding position by an amount of deviation between the position where the thrust plate 8 first strikes the sheet bundle Sa and the folding position where the folding roller pair 3 is folded. This deviation amount is an amount based on information on the sheet bundle.

  In the above description, for example, when the number of sheet bundles is equal to or greater than a predetermined number, the leading end regulating member 1 is moved to a position where the leading end position of the pushing plate 8 is lower than the stapling position by a predetermined amount. Explained.

  However, the position of the leading edge regulating member 1 may be controlled so that the difference in height between the leading edge position of the abutting plate 8 and the staple position increases each time the number of sheet bundles increases. Also in this case, the difference in height between the tip position and the stapling position of the abutting plate 8 is assumed to be the amount of deviation between the position where the abutting plate 8 first abuts against the sheet bundle Sa and the folding position where the folding roller pair 3 is folded. The amount is

  FIG. 6 is a system block diagram showing a system of the copying machine main body 300 and the finisher 500 that perform the above control.

  In FIG. 6A, reference numeral 301 denotes a control unit that is provided in the copying machine main body 300 and controls the entire image forming operation of the copying machine main body 300. An operation unit 302, a sheet feeding unit 1002, an image forming unit 1003, a fixing device 117, and a scanner 200 are connected to the control unit 301.

  A control unit 501 is provided in the finisher 500 and controls the entire sheet processing operation of the finisher 500. The control unit 501 is connected to a control unit 301 on the copier body side. Further, the control unit 501 includes a conveyance unit 516 that drives the buffer roller 513 to convey the sheet, a discharge stacking unit 52 that drives the discharge roller pair 519 to discharge and stack the sheet, a staple unit 600, and a saddle stitch unit. 800 is connected.

  Here, as shown in FIG. 6B, the saddle stitch unit 800 conveys the sheets to the intermediate stacking tray 2 and aligns the conveyed sheets, the staple aligning unit 2A, the stapling unit 7A, the folding roller pair 3 and the pushing roller. A protruding portion 8A provided with the plate 8 is provided. In addition, a bundle discharge unit 245A that discharges the folded sheet bundle Sa to the discharge tray 246 by driving the discharge roller 245 is provided.

  The transport alignment unit 2A includes a transport motor M for transporting sheets to the intermediate stacking tray 2 and a path sensor S1 for detecting that the sheets have been transported to the intermediate stacking tray 2. Further, a width alignment motor M1 for moving a width alignment member (not shown) that performs alignment in the width direction of the sheet bundle before the stapling operation, and a width alignment home position for controlling the position of the width alignment member (not shown). A sensor S2 is provided. Furthermore, a tip restricting member moving motor M2 and a tip restricting home position sensor 13 as the driving means 12 described above are provided.

  When performing saddle stitch binding with such a block configuration, the user first selects the bookbinding mode by the operation unit 302 provided in the copying machine main body 300. Thereafter, when the document size, sheet size, sheet type, presence / absence of saddle stitching, number of copies, and the like are input, the image reading unit 200 reads the image and the image forming unit 1003 forms an image on the sheet. The sheet is discharged from the copying machine main body 300. Further, the control unit 301 on the copier body side prompts the finisher side control unit 501 to convey the sheet discharged from the copier body 300 to the saddle stitch unit 800.

  On the other hand, when the stapler information is input from the operation unit 302 via the control unit 301 on the copier body side, the finisher-side control unit 501 that is a control unit that moves the position of the front-end regulation member 1 first begins with the tip regulation member. The moving motor M2 is driven. As a result, the position of the tip regulating member 1 is moved from the home position to a predetermined height to prepare for the stapling operation.

  The position of the front end regulating member 1 at this time is a position based on the information on the sheet bundle. The sheet bundle information is information obtained by a user input to the operation unit 302, a print job transmitted from a personal computer, the number of sheet bundles determined by reading a document, or the like.

  Then, after alignment and stapling, the front end regulating member 1 is lowered by the front end regulating member moving motor M2 based on the sheet size and sheet type information from the operation unit 302 and waits at the folding operation position.

  At this time, as described above, if the determined number of saddle stitches is 15 or more, for example, the descending amount is decreased by a predetermined amount. If the thick paper mode is set from the operation unit 302, the descending amount is decreased by a predetermined amount. Further, if the large size is set by the operation unit 302, the descending amount is decreased by a predetermined amount. The predetermined amount of descent is obtained by experiments or the like, and is stored in a storage unit (not shown) provided in the control unit 501.

  If the original to be read is a color original and color printing is designated, the image forming unit 1003 recognizes the presence or absence of an image at the center of the sheet, and then the information input from the control unit 301 on the main body side is used. Accordingly, the descending amount is decreased by a predetermined amount.

  In this way, the front end regulating member 1 is selectively set so that the position of the sheet bundle Sa against which the abutting plate 8 abuts is the stapling position of the sheet bundle Sa or a position deviating from the stapling position, in this case, the position below the stapling position. When the sheet bundle Sa is bent, the protruding position and the staple position can be matched. As a result, the folding position shift due to the difference in the number of sheets and the paper type is eliminated, and the sheet bundle having a good appearance can be bound.

  Since the tip regulating member 1 is a member whose position is variable depending on the size, it is not necessary to provide a new mechanism for performing the above control.

  By the way, in the description so far, when the sheet bundle Sa is heavy and cannot be lifted at the time of bending, the case where the set position of the leading end regulating member 1 is raised more than usual has been described.

  However, as shown in FIG. 7, for example, the path above the folding position of the intermediate stacking tray 2 may have an R shape due to the arrangement of the finisher 500. When thick paper is set in such a path, if the sheet is struck by the thrust plate 8, the sheet bundle may be caught by the conveyance resistance above the thrust plate 8, and the sheet bundle may not be pulled down.

  For this reason, in such a case, the set position of the tip regulating member 1 at the time of folding is set lower than the normal position indicated by the broken line, and the set position of the tip regulating member 1 is lowered than usual. Take control. As a result, when the pushing operation by the pushing plate 8 is started, the initial pushing position is above the stapling position, but when the pushing operation proceeds, the lower end of the sheet bundle Sa is lifted and the leading end of the pushing plate approaches the stapling position. It becomes like this. Then, when the sheet bundle Sa eventually enters the nip of the folding roller pair 3, the protruding position and the staple position coincide with each other.

  As described above, when the sheet bundle Sa cannot be pulled down, the position of the leading end regulating member 1 is selectively moved to a position above the staple position that is out of the staple position. The position and the staple position can be matched. As a result, the folding position deviation is eliminated, and the sheet bundle having a good appearance can be bound.

  An example in which a control unit that controls the entire sheet processing operation of the finisher 500 is provided in the finisher 500 is illustrated. However, a control unit that controls the operation of the finisher 500 may be provided in the copying machine main body 300 that is an image forming apparatus, and the operation of the finisher 500 may be controlled by the control unit provided in the copying machine main body 300.

DESCRIPTION OF SYMBOLS 1 Front-end | tip control member 2 Intermediate | middle stacking tray 3 Folding roller pair 7A Staple part 8 Abutting plate 8A Pushing part 9 Drive means 10 Link means 11 Belt apparatus 300 Copier main body 301 Control section 500 on the copier main body side Finisher 501 Part 800 saddle stitch part 1000 copier 1003 image forming part Sa sheet bundle

Claims (9)

In the sheet processing apparatus that performs processing for folding the sheet over sheet bundle at a predetermined bending position,
A sheet stacking unit for stacking sheets in a standing state;
A sheet bundle supporting member that contacts the lower end of the sheet bundle stacked on the sheet stacking unit to support the sheet bundle and is movable in a direction along the sheet stacking unit;
Said sheet bundle supporting member to the support sheet bundle in fold folding rollers, said sheet bundle supporting member abuts on the sheet bundle supported by the protruded section pushed into the folding roller pair nip while folding the sheet stack And a fold portion provided with,
Control means for moving the sheet bundle support member and controlling the position of the sheet bundle against which the ejecting means abuts ,
Wherein, in the displacement amount of the bending positions of the previous Kisho constant of said protruding means the protruding means occur depending on the smoothness of the surface of the sheet bundle in a position impinging on the sheet bundle abuts against the sheet bundle, sheet processing apparatus characterized by controlling so as to move the sheet bundle supporting member such that said protruding means abuts against the sheet bundle Rashi not from the predetermined bending position. The control means, the sheet bundle supporting member to the support sheet bundle, the said sheet bundle supporting member in accordance with the image of the surface of the protruding means abuts position, said protruding means abuts against the sheet bundle position before Symbol a position Tokoro a constant folding position to support the sheet bundle so as to be substantially coincident, and a position where the protruding section abuts position the sheet bundle to support the sheet bundle so as to shift the shift amount from the predetermined bending position the sheet processing apparatus according to claim 1, wherein the controller controls so as to move in two election択的. The control unit is configured such that when there is a color image on the surface of the sheet bundle supported by the sheet bundle support member at a position where the projecting unit abuts, the position of the sheet bundle against which the ejecting unit abuts is more than when there is a black and white image. 3. The sheet processing apparatus according to claim 1, wherein the sheet bundle supporting member is controlled to move to a position below a predetermined folding position of the sheet bundle. When there is a color image on the surface of the sheet bundle supported by the sheet bundle support member at a position where the protrusion means abuts , the control means is more than the position of the sheet bundle where the protrusion means abuts than when there is no image. The sheet processing apparatus according to claim 1, wherein the sheet bundle supporting member is controlled to move to a position below a predetermined folding position of the sheet bundle. Comprising a binding means to bind the sheet bundle supported by the sheet bundle supporting member, before bending position of Kisho constant shall be consistent with the position stapled sheet bundle supported by the sheet stack support member by said stapling means The sheet processing apparatus according to claim 1, wherein: The sheet bundle supported on the sheet bundle supporting member, pre-Symbol sheet processing apparatus according to claim 5, characterized in that the center stapled in the moving direction of the sheet bundle supporting member. The sheet processing apparatus according to claim 1, wherein the sheet bundle stacked on the sheet stacking unit is in a substantially vertical state. An image forming unit for forming an image, characterized in that and a sheet processing apparatus according to any one of claims 1 to 7, bookbinding processing sheet on which an image is formed by the image forming section Image forming system. A pair of folding rollers bend Ri folded sheet bundle abuts against the sheet bundle stacked on the sheet stacking portion for stacking in a standing state the sheet bundle, the protruding section pushed into the nip of the folding rollers while folding the sheet stack, And a sheet bundle support capable of moving in a direction along the sheet stacking section while supporting the sheet bundle by contacting a lower end of the sheet stack stacked in a standing state on the sheet stacking section. An image forming apparatus connected to a sheet processing apparatus that performs a process of bending the sheet bundle supported by the sheet bundle support member at the predetermined folding position.
A control means for controlling movement of the sheet bundle supporting member in order to change the protruding means abuts position the sheet bundle supported by the sheet bundle supporting member,
Wherein, in the displacement amount of the bending positions of the previous Kisho constant of said protruding means the protruding means occur depending on the smoothness of the surface of the sheet bundle in a position impinging on the sheet bundle abuts against the sheet bundle, image forming apparatus and controlling so as to move the sheet bundle supporting member such that said protruding means abuts against the sheet bundle Rashi not from the predetermined bending position.

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