JP2007075935A - Sheet cutting device and image forming device with sheet cutting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress entering of recording sheet pieces and foreign matters, etc. into a cutting means, to prevent generation of jam within the cutting means, and to prevent damage to the cutting means. <P>SOLUTION: This sheet cutting device has: carrying means 6 and 11 connected to an image forming device to receive the recording sheet formed with images from the image forming device and carry the recording sheet; and first and second cutting mechanisms 4 and 5 for cutting the recording sheet carried by the carrying means 6 and 11. In the vicinity of each of the first and second cutting mechanisms 4 and 5, shielding walls 2a, 2b:3a, 3b for opening/closing a carrier path leading to the first and second cutting mechanisms 4 and 5 are provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet cutting apparatus and an image forming apparatus with a sheet cutting apparatus, and more particularly to sheet cutting used in image forming apparatuses such as printers, copiers, facsimiles, and multi-function machines using electrophotography, electrostatic recording, and the like. It is suitable for application to an apparatus.

  In the image forming apparatus, when a recording sheet is jammed (jammed), the recording sheet is generally manually removed from the conveyance path and processed. However, during this jam processing, the recording sheet may be torn and a recording sheet piece may be left on the conveyance path. Alternatively, there is a possibility that foreign matter may enter the transport path due to damage to internal parts or intrusion from outside during processing operations. In an image forming apparatus equipped with a sheet cutting device, when such a jam occurs upstream of the sheet cutting device, when the image forming device is restarted after the jam processing, these recording sheet pieces and foreign matters are processed next. Prior to the recording sheet to be recorded, it is conveyed to the sheet cutting apparatus and enters the apparatus, thereby causing a problem of damage to cutting means such as a cutting blade or a new jam.

  Conventionally, the following proposals have been made regarding jamming suppression and foreign matter intrusion prevention in such a sheet cutting apparatus.

  First, as a recording sheet cutting apparatus, there is a so-called rotary cutting apparatus including a circular moving blade and a fixed blade. With respect to this rotary cutting apparatus, Patent Document 1 proposes a sheet cutting apparatus having means for avoiding paper jams. The cutting device is such that a movable cutter shutter is provided at the opening on the paper conveyance path on the movement trajectory of the circular moving blade base of the cutting means, so that the paper leading edge is guided to the paper guide by the cutter shutter during paper conveyance. It is configured as described above.

  Further, as a cutting device of another cutting method, the cutting means has a fixed blade body and a rotating blade so that the blade body having a rotating mechanism approaches the long blade edge of the fixed blade body in order from the turning center. There is a scissors-type cutting device in which the body is arranged diagonally. With respect to the scissors-type cutting device, in Patent Document 2, a protector for preventing foreign matter from entering from the paper discharge port is provided at a position that narrows the gap between the blade of the fixed blade body and the rotating blade body of the cutting means. A cutting apparatus has been proposed.

Further, Patent Document 3 proposes a cutting device that improves the ease of processing at the time of paper jam, with respect to a cutting device in which the cutting means contacts and separates the movable blade body substantially horizontally with respect to the long blade edge of the fixed blade body. ing. The cutting device is provided with elastic support means for driving the movable blade of the cutting means to the home position, and when the movable blade is released from the fixed blade, the movable blade and the motor are disconnected and the movable blade is released. The cutting device is configured to automatically return to the home position.
JP 2001-206624 A JP 2000-61885 A Japanese Patent Laid-Open No. 2003-311676

In the above-mentioned Patent Document 1, a measure for suppressing the occurrence of jam in the cutting means is proposed. However, the proposal here is to provide a cutter shutter having a guide surface for smoothly transferring the leading edge of the recording sheet conveyed to the cutting means to the conveyance guide downstream of the cutting means. The conveyance path has a gap through which the recording sheet can be conveyed (described in paragraph [0005]). Accordingly, when a small number of recording sheet pieces, foreign matter, etc. are conveyed, they can enter the cutting means.

  As described above, if a recording sheet piece, foreign matter, or the like enters the cutting means prior to the next recording sheet to be processed, the cutting means may be damaged or a new jam may occur. It is clear that a great deal of labor, time and cost are required to repair the cutting means in the event of damage, but even if the cutting means does not result in damage, It is very likely to cause great damage. This is because the cutting device is generally arranged as a final processing device in the finishing device connected to the image forming device.

  Because of this feature, after a re-operation of the image forming apparatus as described above, if a jam occurs in the cutting apparatus during the continuous processing operation, the recording sheet supply apparatus to the image forming apparatus and further the finishing apparatus are used for the jam processing. Therefore, it is necessary to remove a large amount of recording sheets on a very long path leading to. Finished recording sheets are often expensive, with a special coating on the surface for high gloss, and it is very uneconomical to dispose of such recording sheets in large quantities. In addition, the user is forced to perform complicated work. Since such a large damage may be caused, it is desirable to prevent any intrusion of foreign matter or the like into the cutting apparatus even if it is insignificant.

  In Patent Document 2, there is a proposal to provide a protector for preventing foreign matter from entering the cutting means from the outside. However, since this protector is provided for the purpose of preventing the entry of foreign matter from the downstream side (described in paragraph [0005]), a recording sheet piece conveyed from the upstream side through the conveyance path or There is no effect to prevent the intrusion of foreign matter or the like. Therefore, it is possible for recording sheet pieces and foreign matters other than the cutting target to enter the cutting apparatus, and there is a high possibility of inducing the above problem.

  Further, the protector allows the leading edge of the recording paper to be smoothly curved and passed (described in the paragraph [0019]), and a gap is formed to allow the recording paper to pass. When the cutting device is not movable, a gap is set although it is small (see the description in the paragraph [0019]). In the configuration of Patent Document 2, it is possible to prevent a slight foreign matter from entering the cutting means. difficult.

  Patent Document 3 proposes a cutting device including elastic support means for returning the movable blade to the home position when the movable blade of the cutting means is released. Furthermore, using the characteristics of the above configuration, the movable blade is placed between the home position and the cut position after the cutting operation as a paper pressing means for paper that leaves part of the center or edge (partial cut). Has been proposed (described in paragraph [0012]). However, in order to hold the partially cut sheet, the movable blade edge and the fixed blade edge must be separated from each other at least by the width not less than the uncut width. Therefore, as described above, it is not possible to prevent the invasion of a small amount of foreign matter which is a problem of the present invention.

  As described above, any of the conventional cutting apparatuses cannot completely prevent the recording sheet piece or foreign matter conveyed from the upstream of the cutting means from entering the cutting means.

  The present invention has been made in order to solve the above-described problems, and its main purpose is to suppress the entry of sheets, foreign matters, etc. into the cutting means, and to generate a jam in the cutting means. It is an object of the present invention to provide a sheet cutting apparatus and an image forming apparatus with a sheet cutting apparatus that can prevent the cutting unit from being damaged.

  In order to achieve the above object, the present invention provides a sheet cutting apparatus having a conveying means for conveying a sheet and at least one cutting means for cutting a sheet conveyed by the conveying means, in the vicinity of the cutting means. Further, the present invention is characterized in that a shielding unit is provided that can open and close a conveyance path leading to the cutting unit.

  According to the sheet cutting apparatus of the present invention, by providing a shielding means capable of opening and closing the conveyance path in the vicinity of the cutting means, a recording sheet piece or a foreign matter or the like conveyed from the upstream of the cutting means except during the cutting operation. Intrusion into the cutting means can be suppressed at a high level. Thereby, it is possible to prevent the occurrence of jam in the cutting means and to prevent the cutting means from being damaged. Furthermore, by preventing these troubles in advance, not only troublesome trouble-handling work is prevented, but also high-value sheets such as high-gloss processed recording sheets are prevented from being lost for trouble-shooting. And has the effect of preventing economic loss.

  The shielding means is preferably provided upstream and downstream of the cutting means.

  In addition, it is preferable that a conveyance path for conveying the sheet is provided upstream and downstream of the cutting unit, and the shielding unit is provided in close proximity to the upstream and downstream of the cutting unit.

  The shielding means in the present invention is not limited to another member different from the cutting blade arranged close to the cutting means, and the cutting blade can have a function as a shielding means. For example, if the side surface of the movable cutting blade prevents entry of foreign matter or the like into the cutting means within the operation range, it can be used as a shielding means.

  When the cutting means is provided at a plurality of locations in the sheet conveyance direction, it is preferable that a shielding means is provided for each of the cutting means.

  The control of the shielding means is preferably provided with a control means for controlling the shielding means to be in an open state when cutting by the cutting means and to close the shielding means after completion of cutting.

  Further, the control unit is configured to move the shielding unit and the cutting unit to a position that does not hinder the conveyance of the sheet while the sheet to be cut passes through the conveyance path on the upstream side of the cutting unit and is conveyed to the cutting position in the cutting unit. The sheet is retracted, and after the sheet reaches the cutting position, the cutting operation by the cutting means is started. It is preferable to have a control mode in which, after the trailing edge of the sheet passes through the cutting means, the shielding means is operated to shield the conveyance path.

  An image forming apparatus with a sheet cutting apparatus includes an image forming apparatus main body and the sheet cutting apparatus connected to the image forming apparatus main body, and a sheet cutting apparatus for recording sheets formed by the image forming apparatus main body. It is characterized by cutting by.

  The recording sheet cutting device is suitable when it is provided on the downstream side of the re-fixing device for re-fixing the recording sheet discharged from the image forming apparatus main body.

  Hereinafter, the present invention will be described in detail based on illustrated embodiments.

  FIG. 1 shows an example of a sheet cutting apparatus according to an embodiment of the present invention and an image forming apparatus with a sheet cutting apparatus using the sheet cutting apparatus.

  The image forming apparatus is a multicolor image forming apparatus (color copying machine), and includes an image forming apparatus main body 200 and a finishing apparatus 300 connected to the image forming apparatus main body 200 for finishing a recording sheet on which an image is formed. The sheet cutting device 1 is incorporated in the finishing device 300. Note that the gist of the present invention does not change even if the image forming apparatus is a monochrome image forming apparatus.

  The image forming apparatus main body 200 includes a document placing table 206, a light source 207-1, a lens system 207-3, a paper feeding unit 209, an image forming unit 202, and the like. The sheet feeding unit 209 includes cassettes 210 and 211 and a manual feed cassette 212 that store a large number of recording sheets and can be freely attached to and detached from the apparatus main body 200, and recording sheets are supplied from the cassettes 210 and 211 and the manual feed cassette 212. . In the image forming unit 202, a black developing device 203 configured separately, a cylindrical photosensitive drum 213, a primary charger 214, and a rotary developing device 201 including a plurality of developing devices 215 integrated with a toner cartridge, Post-charger 216 for adjusting the image quality after development, an endless annular transfer belt 217 for transferring a multicolor image onto a recording sheet after transferring and forming a toner image of four colors, and cleaning the residual toner on the photosensitive drum A drum cleaner 218 that performs transfer, a secondary transfer roller 219 that transfers a toner image from a transfer belt to a recording sheet, a belt cleaner 220 that cleans residual toner on the transfer belt, and the like are provided.

  A registration roller 221 is provided on the upstream side of the image forming unit 202 to improve the posture position accuracy of the recording sheet and feed the recording sheet in time with the toner image on the transfer belt 217, and the toner image is transferred on the downstream side. A transfer conveyance device 222 for conveying the recording sheet S, a fixing unit 204 for fixing an unfixed image on the recording sheet S, a discharge roller 205 for discharging the recording sheet S on which the image is fixed to the outside of the image forming apparatus, and the like. It is arranged.

  The finishing device 300 includes a re-fixing device 301 for performing high gloss processing on a recording sheet output from the image forming device, a sheet cutting device 1 for cutting and discharging the re-fixed recording sheet, and a sheet cutting device. 1 includes a pre-cutting conveyance roller 302 for conveyance to No. 1 and a paper discharge path 303 for discharging a recording sheet on which an image has been formed without performing a finishing process.

  Next, the operation of this image forming apparatus will be described.

  When a paper feed signal is output from a control device (not shown) provided on the apparatus main body 200, the recording sheet S is supplied from the cassettes 210 and 211 or the manual feed cassette 212. On the other hand, the light irradiated and reflected from the light source 207-1 to the document D placed on the document placing table 206 is once read by the CCD unit 207-2, and then converted into an electric signal to be converted into the laser scanner unit 208. Then, the photosensitive drum 213 is irradiated with the laser beam. The photosensitive drum 213 is charged in advance by a primary charger 214, and an electrostatic latent image is formed by light irradiation, and then a plurality of developing units disposed in the black developing unit 203 and the rotary developing unit 201. By 215, the toner image of the selected color is formed.

The potential of the toner image formed on the photosensitive drum 213 is adjusted by the post charger 216, and is eventually transferred onto the transfer belt 217 at the transfer position. When the transferred toner image is in the color mode, the transfer belt 217 is further rotated once so that the next toner image is formed and transferred. During this time, the rotary developing device 201 rotates the next designated color developing device in the direction of the arrow a so as to face the photosensitive drum 213 and prepares to develop the next electrostatic latent image. Thus, in the full-color mode, electrostatic latent image formation, development, and transfer are repeated until a predetermined number of toner images have been transferred.

  By the way, the recording sheet S fed from the paper feeding unit 209 is corrected in skew by the registration roller 221, and further sent to the image forming unit 202 at a proper timing. Then, the toner image is transferred by the secondary transfer roller 219, and the separated recording sheet S is conveyed to the fixing unit 204 by the conveying device 222, and the unfixed transfer image on the recording sheet S by the heat and pressure of the fixing unit 204. Is permanently fixed. The recording sheet S on which the image is fixed is discharged from the apparatus main body 200 by a discharge roller 205.

  In this way, the recording sheet S fed from the paper feeding unit 209 forms an image and is discharged.

  The image forming apparatus main body 200 according to the present invention has a double-sided image forming function. This double-sided image forming operation will be described mainly based on the conveyance state of the recording sheet S.

  The recording sheet S after the fixing of the first surface by the fixing unit 204 is branched downward by the reverse flapper mechanism indicated by 111 in the figure, and is conveyed to the reverse conveyance path 101 arranged downstream of the reverse branch point. The

  Next, the recording sheet S that is switched back by the reverse conveyance path 101 is branched by the double-sided flapper mechanism 112 in a state where the front and back sides are reversed, and is drawn into the double-sided conveyance path 102 and retransmitted to the image forming unit. Has been. Incidentally, if the paper is discharged by the discharge roller 205 while being reversed from the reverse conveyance path 101, it functions as a reverse paper discharge mode.

  Thus, the recording sheet S re-conveyed in the reverse conveyance path 101 and the double-sided conveyance path 102 is eventually retransmitted to the registration rollers 221. In this way, a toner image is formed on the second surface of the recording sheet S. The other image forming process and the recording sheet S conveying process are the same as the above-described single-sided image forming mode, and thus the description thereof is omitted here.

  The recording sheet on which the image is formed in this manner is discharged from the image forming apparatus main body 200 by the discharge roller 205 and is simultaneously conveyed to the finishing apparatus 300. When reprocessing is not performed, the recording sheet is conveyed to the conveyance path 303 and is discharged out of the apparatus. On the other hand, when reprocessing is performed, the recording sheet is conveyed to the re-fixing device 301 and heated and pressed to perform high gloss processing on the image forming surface. The recording sheet is cooled by a cooling unit provided in a downstream conveyance path of the re-fixing device 301, and then conveyed to the sheet cutting device 1 by a pre-cutting conveyance roller 302, and after being cut, is discharged from the finishing device 300. .

  FIG. 2 is a diagram showing a main cross section of the sheet cutting apparatus 1 that is the most characteristic of the present invention.

  The sheet cutting apparatus 1 shown in this figure includes a pre-cutting conveyance roller 302 that conveys a sheet constituting a conveyance unit, a registration roller pair 8 in a registration unit 6, conveyance roller pairs 11 and 15, and a recording sheet conveyance direction. A first cutting mechanism 4 serving as a first cutting means for cutting the recording sheet in a direction orthogonal to the first cutting mechanism; a second cutting mechanism disposed downstream of the first cutting mechanism 4 for cutting the recording sheet in a direction substantially parallel to the conveyance direction of the recording sheet. It has the 2nd cutting mechanism 5 as a cutting means.

More specifically, the first cutting mechanism 4 is driven by fixed blades 4a and 4b that are fixed to the sheet cutting apparatus 1 and have a plate shape longer than the recording sheet width, and driving means (not shown). And a movable blade 4c that contacts and separates in a substantially parallel manner with respect to the long blade edges of the fixed blades 4a and 4b. More specifically, the second cutting mechanism 5 has a blade surface substantially parallel to the recording sheet conveyance direction, and is positioned at a position facing the circular rotary blade 5a that is rotationally driven by a driving means (not shown) and the circular rotary blade 5a. The cutting means includes a circular rotary blade 5b that sandwiches and cuts the recording sheet with the circular rotary blade 5a and cuts the recording sheet and conveys the recording sheet.

  Even if the first cutting mechanism 4 and the second cutting mechanism 5 are cutting means other than the cutting means shown in this figure (for example, vertical cutting means or moving rotary cutting means), the gist of the present invention will be changed. There is no.

  The upstream and downstream side surfaces of the movable blade 4c of the first cutting mechanism 4 are shielding walls 2a and 2b that also function as shielding means that can open and close the conveyance path leading to the first cutting mechanism 4. .

  Further, on the upstream side and the downstream side in the vicinity of the second cutting mechanism 5, shielding walls 3 a and 3 b that are driven independently or in conjunction with each other to open and close the conveyance path leading to the second cutting mechanism 5 are arranged. Has been.

  Upstream of the first cutting mechanism 4, an image-formed recording sheet is received, the orientation of the recording sheet is corrected in a direction substantially perpendicular to the conveying direction, and then the recording sheet skew correction (which constitutes the conveying means for conveying) ( A resist portion 6 is disposed. The registration unit 6 receives a recording sheet conveyed from the image forming unit disposed upstream of the registration unit 6 via the re-fixing unit 301, the pre-cutting roller 302, and the conveyance path 304, and guides the recording sheet 7 downstream. Have The guide 7 has a pair of upper and lower guide plates 7a and 7b. Further, the recording sheet conveyed through the guide 7 is abutted against the nip portion, and after correcting the posture of the recording sheet in a direction substantially perpendicular to the conveying direction, the registration roller pair 8 that conveys the recording sheet is rotated. Has been. The registration roller pair 8 is composed of a pair of rollers 8a and 8b that are in contact with each other. Further, sheet detecting devices 9 and 10 are provided respectively upstream and downstream of the registration roller pair 8 and detect the passing timing of the recording sheet. In the example of illustration, each sheet | seat detection apparatus 9 and 10 is a transmissive | pervious sensor, and is comprised by a pair of detection element 9a, 9b; 10a, 10b.

  Downstream of the first cutting mechanism 4 is disposed a pair of conveying rollers 11 as conveying means for conveying the recording sheet cut by the first cutting mechanism 4 to the second cutting mechanism 5. A guide 12 for guiding the recording sheet from the first cutting mechanism 4 to the conveying roller pair 11 and a guide 13 for guiding the recording sheet from the conveying roller pair 11 to the second cutting mechanism 5 are arranged. Further, downstream of the second cutting mechanism 5, a paper discharge tray 14 for stacking the output product after cutting, and a pair of transport rollers for transporting the recording sheet cut by the second cutting mechanism 5 to the paper discharge tray 14. 15 and a guide 16 for guiding the recording sheet from the second cutting mechanism 5 to the conveying roller pair 15.

  Next, the operation of the sheet cutting apparatus 1 will be described.

  When the recording sheet is conveyed from the re-fixing unit 301 disposed upstream of the sheet cutting apparatus 1, the recording sheet is guided to the registration roller pair 8 by the guide 7 and abuts against the roller nip portion. After the recording sheet is detected by the pre-registration sheet detecting device 9, the registration roller pair 8 is started to drive at an appropriate timing, thereby forming an appropriate recording sheet loop in the guide 7 before the start of driving. The recording sheet is conveyed with the line correction. Until the timing when the registration roller pair 8 starts to drive and the recording sheet reaches the upstream opening of the first cutting mechanism 4, the shielding walls 2a, 2b and the shielding walls 3a, 3b constituted by both side surfaces of the movable blade 4c are The conveyance path is shielded, and the recording sheet piece or foreign matter is waiting at a position where it does not enter the first and second cutting mechanisms 4 and 5.

  Next, the recording sheet passes through the upstream opening of the first cutting mechanism 4 by the registration roller pair 8 and is conveyed to the first cutting mechanism 4. At this time, the movable blade 4c, which is also a shielding means, reaches a position that does not prevent the recording sheet from being conveyed to the first cutting mechanism 4 in accordance with the timing when the recording sheet reaches the upstream opening of the first cutting mechanism 4. Moved and evacuated. Therefore, the shielding walls 2a and 2b configured by the upstream and downstream side surfaces of the movable blade 4c also move to the position where the recording sheet is not prevented from being conveyed to the first cutting mechanism 4 and retract.

  The recording sheet can be cut at a predetermined position by starting the cutting operation of the first cutting mechanism 4 after the recording sheet is conveyed by a predetermined amount after the registration sheet detection apparatus 10 detects the recording sheet. it can. The recording sheet cut by the first cutting mechanism 4 passes through the guides 12 and 13 by the conveying roller pair 11, passes through the upstream opening of the second cutting mechanism 5, and is conveyed to the second cutting mechanism 5.

  At this time, the recording sheet is prevented from being conveyed to the second cutting mechanism 5 through the upstream and downstream shielding walls 3 a and 3 b in accordance with the timing when the leading edge of the recording sheet reaches the upstream opening of the second cutting mechanism 5. Evacuate to a position that does not exist at the same time or with a certain time difference. Note that the movable blade 4c functioning as a shielding means immediately after the recording sheet trailing edge passes through the upstream opening or the downstream opening of the first cutting mechanism 4 is moved to a position where the conveyance path is shielded. The cutting portion is shielded by the shielding walls 2a and 2b on the upstream and downstream sides of 4c. The recording sheet conveyed to the second cutting mechanism 5 is cut in a direction substantially parallel to the conveying direction by the second cutting mechanism 5, passes through the guide 16, and is conveyed to the paper discharge tray 14 by the conveying roller 15. Loaded.

  In addition, immediately after the trailing edge of the recording sheet passes through the upstream opening or the downstream opening of the second cutting mechanism 5, the shielding walls 3a and 3b are moved simultaneously or with a certain time difference to a position where the conveyance path is shielded.

  Next, the operation of the first cutting mechanism 4 will be described in more detail according to the recording sheet processing procedure.

  FIG. 3 is a detailed view showing the state of the movable blade 4 c of the first cutting mechanism 4 immediately before the recording sheet S is conveyed by the registration roller pair 8. As shown in the figure, until the timing when the registration roller pair 8 starts to drive and the leading edge of the recording sheet reaches the upstream opening of the first cutting mechanism 4, the shielding walls 2a and 2b formed by the side surfaces of the movable blade 4c. Stands by at a position that blocks the conveyance path.

  4, the leading end of the recording sheet is conveyed by the registration roller pair 8 from the standby state of FIG. 3, passes through the upstream opening of the first cutting mechanism 4, and passes through the guide 12 positioned downstream of the first cutting mechanism 4. FIG. 5 is a detailed view showing a state in which a predetermined cutting position on the recording sheet has reached the cutting position of the first cutting mechanism 4 after entering the nip portion of the conveying roller pair 11 and being conveyed. 4 shows the state of the cutting means 4 immediately before the start of the cutting operation. The conveying roller pair 11 is constituted by a pair of rollers 11a and 11b, and the guide 12 is constituted by a pair of upper and lower guide plates 12a and 12b.

  The shielding walls 2 a and 2 b which are the side surfaces of the movable blade 4 c of the first cutting mechanism 4 are arranged so that the recording sheet is aligned with the timing when the leading end of the recording sheet reaches the upstream opening of the first cutting mechanism 4. Retreat to a position that does not prevent it from being conveyed. Therefore, the leading edge of the recording sheet can smoothly pass through the upstream opening and the downstream opening of the first cutting mechanism 4 and reach the conveying roller pair 11.

FIG. 5 shows a state of the first cutting mechanism 4 immediately after the cutting operation is started after the cutting position on the recording sheet reaches the cutting position of the first cutting mechanism 4 and the recording sheet is cut. FIG.

  At this time, the shielding walls 2a and 2b constituted by the side surfaces of the movable blade 4c move in the direction of the arrow b to the position where the conveyance path is shielded simultaneously with the cutting operation. Since the recording sheet is stopped with respect to the first cutting mechanism 4 during the cutting operation, the conveyance of the recording sheet is not hindered by the shielding walls 2a and 2b.

  FIG. 6 shows that after the cutting operation is finished, the movable blade 4c is retracted to a position that does not hinder the conveyance of the recording sheet, and then the cut recording sheet is conveyed by the registration roller pair 8 and the conveyance roller pair 11, and the trailing edge of the recording sheet is FIG. 5 is a detailed view showing the state of the first cutting mechanism 4 immediately after passing through the downstream opening of the first cutting mechanism 4. The shielding walls 2a and 2b on the side surfaces of the movable blade 4c move in the direction of the arrow b to the position where the trailing edge of the recording sheet shields the conveyance path immediately after passing the downstream opening of the first cutting mechanism 4.

  In addition, by monitoring the conveyance amount after the sheet leading edge is detected by the sheet detecting device 10 after registration, the recording sheet trailing edge is matched with the timing when the recording sheet trailing edge passes through the upstream opening and the downstream opening of the first cutting mechanism 4. The shielding walls 2a and 2b can be operated. The shielding walls 2a and 2b stand by at a position for shielding the conveyance path until the next recording sheet is conveyed.

  As described above, the shielding means constituted by the first cutting mechanism 4 and the movable blade 4c of the first cutting mechanism 4 repeats the operations shown in FIG. 3, FIG. 4, FIG. 5, and FIG.

  6 is omitted between successive recording sheets, the cutting operation shown in FIGS. 3, 4, and 5 is repeated, and after the last recording sheet processing is performed. You may perform the shielding operation | movement shown by FIG. As described above, when the recording sheet is not conveyed by the conveying means in the first cutting mechanism 4, the conveying path is closed by the movable blade 4c.

  The shielding walls 2a and 2b configured by the first cutting mechanism 4 and the movable blade 4c of the first cutting mechanism 4 described above are one example for realizing the present invention, and do not limit the present invention. For example, as shown in FIG. 7, even if it is the cutting device provided with the shielding means 2 which has the shielding walls 2a and 2b which are separate from the movable blade 4c in the upstream and downstream of the movable blade 4c, the shielding walls 2a and 2b are provided. The conveyance path can be shielded by interlocking or driving independently with the movable blade 4c.

  Next, as a second example of the shielding means in the present invention, the operation of the second cutting mechanism 5 and the shielding walls 3a and 3b will be described in detail according to the processing procedure of the recording sheet S.

In FIG. 8, the recording sheets are conveyed by the conveying roller pair 11 and the shielding walls 3a and 3b and the second cutting mechanism 5 immediately before the leading end of the recording sheet reaches the upstream opening of the second cutting mechanism 5 through the guide 13 are shown. It is the detailed figure which showed the state. Until the leading edge of the recording sheet reaches the upstream opening of the second cutting mechanism 5, the upstream and downstream shielding walls 3a and 3b stand by at a position where the conveyance path is shielded. The guide 13 is composed of a pair of upper and lower guide plates 13a and 13b.

FIG. 9 shows the shielding walls 3a and 3b and the second cutting mechanism when the recording sheet passes through the upstream opening of the second cutting mechanism 5 and is cut by the circular rotary blades 5a and 5b from the state of FIG. FIG. 5 is a detailed view showing a state of FIG. The upstream and downstream shielding walls 3a and 3b have the recording sheet leading edge passing through the guides 13 and 16 and the recording sheet at the same time or with a certain time difference in accordance with the timing of reaching the downstream opening from the upstream opening of the second cutting mechanism 5. It moves in the direction of the arrow c to a position where it does not hinder the conveyance, and retracts. The guide 16 is also composed of a pair of upper and lower guide plates 16a and 16b, and the conveying roller pair 15 on the downstream side of the guide 16 is also composed of a pair of rollers 15a and 15b.

FIG. 10 shows the state of the shielding walls 3 a and 3 b and the second cutting mechanism 5 immediately after the trailing edge of the recording sheet cut by the second cutting mechanism 5 passes through the downstream opening of the second cutting mechanism 5. FIG. The upstream and downstream shielding walls 3a and 3b are arranged in the direction of arrow d to the position where the rear end of the recording sheet shields the conveyance path at the same time or immediately after passing through the upstream opening and the downstream opening of the second cutting mechanism 5. Move to. The shielding walls 3a and 3b stand by at a position for shielding the conveyance path until the next recording sheet is conveyed. As described above, the shielding walls 3a and 3b and the second cutting mechanism 5 repeat the operations shown in FIG. 8, FIG. 9, and FIG. As described above, when the recording sheet is not conveyed by the conveying unit in the second cutting mechanism 5, the conveying path is closed by the shielding walls 3a and 3b.

  FIG. 11 shows a block diagram of a control system for controlling the sheet cutting apparatus 1 according to the present invention. FIG. 12 is a flowchart showing the recording sheet cutting pattern in this embodiment. The recording sheet cutting mode, which is a characteristic point of the present invention, will be described with reference to these drawings.

The controller 400 controls the operation of the entire system of the image forming apparatus. Necessary control signals are supplied to the image forming unit 202, the paper feeding unit 209, the fixing device 204, the image reading unit 207, the optical system 208, and the like. Is sent out. The controller 400 drives an actuator such as a drive motor for the movable blade 4c of the first cutting mechanism 4, an actuator such as a drive motor for driving the circular rotary blade 5a of the second cutting mechanism 5, and the shielding walls of the shielding walls 3a and 3b. An actuator such as a solenoid SL is controlled.

  The controller 400 is composed of a microcomputer composed of a CPU, ROM, RAM, and the like. The control program stored in a memory such as a ROM, the operation unit, and the contents of selection instruction information input from other OA devices. The control operation is executed according to the above. A control program related to each operation described later is also stored in a memory such as a ROM.

  The operation unit 410 is provided with keys for inputting instructions for setting, selecting, determining, and executing various conditions for using the image forming apparatus. And a display unit for displaying the information and the like. The display unit may be a general liquid crystal display screen or a lamp. Usually, a touch panel type liquid crystal display screen capable of instructing and inputting information in addition to displaying information is used. The instruction information input through the operation unit is transmitted to the controller. In addition, a predetermined display is performed on the display unit according to the control operation of the controller, the output status from the other OA device 420, or the like.

  In the image forming apparatus according to the present exemplary embodiment, a predetermined instruction is given from the operation unit 410 and the other OA device 420, and a normal output mode in which an image-formed recording sheet is ejected without being cut is registered in advance. Either a cutting output mode for cutting and discharging to a predetermined size can be selected.

  The selection instruction at this time is directly performed by displaying a predetermined input screen or the like from the operation unit 410 including a touch panel type liquid crystal display screen, or is performed in combination with a selection input operation from another OA device 420 or the like.

As for the first cutting mechanism 4, the controller 400 provides a shielding unit while the sheet to be cut passes through the conveyance path on the upstream side of the first cutting mechanism 4 and is conveyed to the cutting position in the first cutting mechanism 4. The movable blade 4c of the first cutting mechanism 4 that functions also as a retracted position that does not hinder the conveyance of the sheet, and after the sheet reaches the cutting position, the movable blade 4c of the first cutting mechanism 4 is driven to perform the cutting operation. After the cutting operation is completed, the movable blade 4c, which also functions as a shielding means, is retracted to a position that does not hinder the conveyance of the sheet, and is movable after the trailing edge of the cut sheet passes through the first cutting mechanism 4. Control is performed so that the blade 4c is driven to block the conveyance path.

  The second cutting mechanism 5 serves as a shielding unit while the recording sheet to be cut passes through the conveyance path on the upstream side of the second cutting mechanism 5 and is conveyed to the cutting position in the second cutting mechanism 5. The shielding walls 3a and 3b and the second cutting mechanism 5 are retracted to a position that does not hinder the conveyance of the recording sheet, and after the recording sheet reaches the cutting position, the cutting operation by the second cutting mechanism 5 is started and the cutting operation ends. After that, the shielding walls 3a and 3b and the second cutting mechanism 5 are retracted to a position that does not hinder the conveyance of the cut recording sheet, and the shielding is performed after the rear end of the cut recording sheet passes through the second cutting mechanism 5. The walls 3a and 3b are operated so as to shield the conveyance path.

  Hereinafter, main operations of the image forming apparatus when each of the output modes described above is selected will be described in detail with reference to the flowchart of FIG.

  When there is an output request from the operation unit 410 or another OA device 420, the controller 400 first determines the output mode (step 1).

  If it is determined that the cutting mode is selected, the controller 400 next determines the cutting size, and from the relationship between the cutting size and the cutting position registered in advance, the direction orthogonal to the transport direction (first cutting) and the parallel direction. The presence / absence of the (second cutting) cutting operation and the cutting position on the recording sheet are determined (step 2).

  Next, the controller forms an image on the recording sheet in the image forming apparatus, conveys it to the finishing apparatus, and performs re-fixing processing (step 3). Next, after correcting the skew before cutting (step 4), the driving of the registration roller is started and the recording sheet is conveyed (step 5).

  Then, the shielding means is at a timing before the leading edge of the recording sheet reaches the upstream opening of the first cutting mechanism 4 and comes into contact with the shielding wall 2a of the movable blade 4c disposed upstream in the vicinity of the second cutting mechanism 4. Is moved and retracted to a position where the conveyance of the recording sheet is not hindered (step 6). That is, even after the shielding wall 2a is retracted, the controller 400 continues to be conveyed by the registration rollers 8, and when the leading edge of the recording sheet reaches the conveying roller pair 11 eventually, it is also conveyed by the conveying roller pair 11 (step 7). When it is determined that the recording sheet has been conveyed to the first cutting mechanism 4 to the cutting position determined in step 2 (step 8), the cutting operation of the movable blade 4c is started and cut (step 9).

  If the recording sheet piece remaining on the upstream side of the movable blade 4c after cutting is unnecessary (step 10), the movable blade 4c maintains the state at the end of cutting, and at the same time by the shielding walls 2a and 2b on both sides of the movable blade 4c. The conveyance path is blocked (step 13). At this time, the unnecessary portion falls from the clearance of the conveyance path provided upstream of the first cutting mechanism 4 and is collected in the sheet piece stacking portion 305.

  When the upstream sheet piece needs to be further cut, or when the upstream sheet piece is required, such as when paper is discharged without being cut (step 10), the conveyance of the recording sheet is hindered immediately after the cutting operation. The movable blade is returned to the position where it is not present (step 11), and the recording sheet continues to be conveyed (step 7).

  Steps 7 to 11 are repeated until all the cutting operations determined in step 2 are completed.

  When the first cutting is completed, the controller estimates the rear end position while conveying the recording sheet by the conveying roller pair 11. When it is determined that the rear end has passed the downstream opening of the first cutting mechanism 4 (step 12), the movable blade 4c of the first cutting mechanism 4 constituting the shielding means is moved to a position where the conveyance path is shielded. (Step 13).

  Thereafter, while the recording sheet is conveyed (step 18), the open / close state of the shielding walls 3a and 3b as the second shielding means is determined (step 19). If the shielding walls 3a and 3b are closed, the recording wall 3a is moved to the recording sheet at a timing when the leading edge of the recording sheet reaches a predetermined position before contacting the shielding wall 3a disposed upstream in the vicinity of the second cutting mechanism 5. It is moved and retracted to a position where it is not hindered (steps 20 and 21), and then driving of the circular rotary blades 5a and 5b is started (step 22).

  Even when it is determined in Step 11 that the rear end does not pass through the downstream opening of the first cutting mechanism 4, the controller 400 always estimates the front end position, and the shielding walls 3a and 3b are the same as in Step 19 to Step 22. And the circular rotary blades 5a and 5b are driven (steps 14, 15, 16, and 17).

  After the drive of the circular rotary blades 5a and 5b is started and the shielding walls 2a and 2b of the movable blade 4c of the first cutting mechanism 4 are moved to the shielding position of the conveyance path, the controller 400 conveys the recording sheet ( (Step 23) The position of the recording sheet is estimated, and when it is determined that the rear end has passed the downstream opening of the second cutting mechanism 5 (Step 24), the driving of the circular rotary blades 5a and 5b is stopped (Step 25). Further, the shielding walls 3a and 3b are moved to a position where the conveyance path is shielded (step 26).

  The second cutting is performed as described above. Finally, the controller discharges the recording sheet cut by the paper discharge roller 15 (step 27), stops the motor of each conveyance roller, and ends the sequence (step 28).

  In this way, the recording sheet is subjected to the cutting process, and the shielding walls 2a and 2b of the movable blade 4c constituting the first shielding means, the first, except when the first and second cutting mechanisms 4 and 5 are cutting. The entry of the first cutting mechanism 4 and the second cutting mechanism 5 into the cutting means such as foreign matters is prevented by the action of the shielding walls 3a and 3b constituting the two shielding means.

1 is a main cross-sectional view of a multicolor image forming apparatus to which a recording sheet conveying apparatus according to an embodiment of the present invention is connected. FIG. 2 is a main cross-sectional view of a recording sheet conveying apparatus connected to the image forming apparatus in FIG. 1. It is a schematic sectional drawing which shows the operation | movement of the 1st cutting means of FIG. It is a schematic sectional drawing which shows the operation | movement of the 1st cutting means of FIG. It is a schematic sectional drawing which shows the operation | movement of the 1st cutting means of FIG. It is a schematic sectional drawing which shows the operation | movement of the 1st cutting means of FIG. It is a schematic sectional drawing which shows the other structural example of the 1st shielding means which shields a 1st cutting means. It is a schematic sectional drawing which shows the operation | movement of the 2nd cutting mechanism of FIG. It is a schematic sectional drawing which shows the operation | movement of the 2nd cutting mechanism of FIG. It is a schematic sectional drawing which shows the operation | movement of the 2nd cutting mechanism of FIG. It is a block diagram explaining the control system of the apparatus of FIG. It is a flowchart figure explaining the control content of the sheet cutting apparatus which concerns on the Example of this invention.

Explanation of symbols

1 Sheet cutting device 2a, 2b Shielding wall (shielding means)
3a, 3b Shielding wall (shielding means)
4 First cutting mechanism (cutting means)
4a, 4b Fixed blade, 4c Movable blade 5 Second cutting mechanism (cutting means)
5a, 5b Circular rotary blade 6 Registration section 8 Registration roller pair, 8a, 8b roller 7 Guide, 7a, 7b Guide plate 9, 10 Sheet detection device 9a, 9b; 10a, 10b Detection element 11, 15 Conveying roller pair 12, 13 , 16 Guide 14 Paper discharge tray 111 Reverse flapper mechanism 101 Reverse transport path 102 Double-sided transport path 200 Image forming apparatus main body 201 Rotary developer 215 Developer 202 Image forming unit 203 Black developer 204 Fixing unit, 205 Discharge roller 206 Document placement table ,
207-1 Light source 207-2 CCD unit 208 Laser scanner unit 209 Paper feed unit 210, 211 Cassette 212 Manual feed cassette 213 Photosensitive drum 214 Primary charger 216 Post charger 217 Transfer belt,
218 Drum cleaner 219 Secondary transfer roller 220 Belt cleaner
221 Registration roller 222 Transfer conveyance device S Recording sheet 300 Finishing device 301 Re-fixing device 302 Pre-cut conveyance roller 303 Paper discharge path 400 Controller (control means)
410 Operation section 420 OA equipment D Document

Claims (10)

Conveying means for conveying the sheet;
In a sheet cutting apparatus having at least one cutting means for cutting a sheet conveyed by the conveying means,
A sheet cutting apparatus comprising: a shielding unit capable of opening and closing a conveyance path leading to the cutting unit in the vicinity of the cutting unit. The sheet cutting apparatus according to claim 1, wherein the shielding unit shields the conveyance path when the conveying unit does not convey the sheet in the cutting unit. The sheet cutting apparatus according to claim 1 or 2, wherein the shielding means is provided upstream and downstream of the cutting means. The sheet cutting device according to any one of claims 1 to 3, wherein the cutting unit includes a cutting blade, and the cutting blade also has a function as a shielding unit. The sheet cutting apparatus according to any one of claims 1 to 3, wherein the shielding means is constituted by a shielding member separate from the cutting means. The sheet cutting device according to any one of claims 1 to 5, wherein the cutting means is provided at a plurality of locations in the sheet conveyance direction, and a shielding means is provided for each of the cutting means. . 7. The apparatus according to claim 1, further comprising a control unit configured to open the shielding unit when the cutting unit performs cutting and to control the shielding unit to a closed state after the cutting is completed. The sheet cutting apparatus according to the description. The control means includes
While the sheet to be cut passes through the conveyance path on the upstream side of the cutting means and is conveyed to the cutting position in the cutting means, the shielding means and the cutting means are retracted to a position that does not hinder the conveyance of the sheet. Let
After the sheet reaches the cutting position, start the cutting operation by the cutting means,
After the cutting operation is completed, the shielding unit and the cutting unit are retracted to a position that does not hinder the conveyance of the cut sheet,
The sheet cutting device according to claim 7, further comprising: a control mode in which, after a trailing end of the cut sheet passes through the cutting unit, the shielding unit is operated to block a conveyance path. An image forming apparatus main body;
The sheet cutting device according to any one of claims 1 to 8, which is connected to the image forming apparatus main body.
An image forming apparatus with a sheet cutting device, wherein a recording sheet formed with an image by the image forming apparatus main body can be cut by the sheet cutting device. The image forming apparatus with a sheet cutting apparatus according to claim 9, wherein the sheet cutting apparatus is provided on a downstream side of a re-fixing apparatus that re-fixes a recording sheet discharged from a main body of the image forming apparatus.

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