JP4695336B2 - Paper processing apparatus and image forming system - Google Patents

Description

  The present invention provides a predetermined process including a Z-folding process on a sheet guided from the sheet output apparatus, which is integrated with or separately from a sheet output apparatus typified by an image forming apparatus such as a copying machine, a printer, and a facsimile machine. The present invention relates to a sheet processing apparatus that performs the above and an image forming system that includes the sheet processing apparatus in the system.

2. Description of the Related Art A sheet processing apparatus that performs a predetermined process on a sheet-like recording medium (hereinafter referred to as a sheet) on which an image is formed by an image forming apparatus is well known. In this type of paper processing apparatus, papers that have been subjected to punching, binding, folding, and the like are discharged and collected in a paper discharge tray or a paper stacking tray. At that time, since there is a limit to the amount of sheets or paper bundles that can be collected, the surface of the uppermost paper of the paper or paper bundle that has been collected on the paper discharge tray or paper stacking tray is generally called a paper surface. Detection is performed by a detection means (paper surface sensor), and processing such as lowering the paper discharge tray or the paper stacking tray or temporarily stopping image formation by the image forming apparatus and paper processing by the paper processing apparatus because the stacking is impossible. It is done. For example, Patent Document 1 describes a paper discharge tray device that performs paper surface detection on the front end side of paper.
JP 2000-143071 A

  However, if the paper surface detection position of the paper loaded on the tray is on the leading edge side of the paper, when the folded paper is loaded on the tray, the paper surface will be detected where the paper is folded and overlapped. Is lowered, the paper surface position is too far from the paper discharge roller, and there is a problem that the alignment of the paper deteriorates.

  For example, the apparatus disclosed in Patent Document 1 is an example in which only the paper filler 341 in FIG. 9 in an embodiment of the present invention described later is provided, and when Z-folded sheets are stacked as shown in FIG. The front end side in the paper discharge direction swells from the rear end side due to folding. Therefore, if the paper surface is detected only at the swollen position, the detected position and the thickness of the rear end are extremely different, and the distance between the paper discharged from the paper discharge port and the paper loaded on the paper discharge tray is It can happen that it is too far away to guarantee good loading.

  SUMMARY An advantage of some aspects of the invention is that it provides a sheet processing apparatus and an image forming system capable of preventing the paper surface from being excessively lowered and improving sheet alignment.

In order to achieve the above object, the first means includes at least two discharge trays, ie, an upper discharge tray and a lower discharge tray that are vertically movable for stacking sheets, and these discharge trays are connected to an end fence. , A first paper surface detecting means for detecting a positional relationship between the upper discharge tray and the lower discharge tray, and a rear end of the paper stacked on the lower discharge tray. In the paper processing apparatus having the second paper surface detecting means for detecting the paper, a return roller for returning the paper discharged to the lower discharge tray to the end fence side on the side of the apparatus and the two discharge trays. A paper discharge roller for paper , a support member that rotatably supports the return roller on one end side, and protrudes from the outer periphery of the return roller, and is placed on the upper surface of the lower discharge tray or the paper surface on the lower discharge tray. Abutting first end And a detection member as the second paper surface detection means having an elongated shape having a second end for detecting the rotational position of the first end, and the inner side of the end fence, on the return roller support side A shaft means for pivotally supporting the support member at an end opposite to the end of the shaft, and pivotably supporting the detection member between the first and second ends; An urging means for elastically urging the support member so that the return roller protrudes from the end fence to a predetermined position on the side surface of the apparatus, and when the return roller protrudes from the end fence by the rotation of the support member, An interlocking means for projecting the detection member in conjunction with the pivoting movement of the support member and storing the detection member in conjunction with the projection when the inner side of the end fence is stored, and the upper discharge tray is in the discharge position. This Due to the lowering operation of the upper discharge tray, the lower end portion of the discharge tray comes into contact with a predetermined position on the upper surface of the support member protruding from the end fence, and resists the elastic biasing force of the biasing means. And the return roller and the detection member are stored in a device inside the end fence.

In the second means, the paper processing apparatus according to the first means and the image forming apparatus that forms a start image on a recording medium and discharges the paper to the paper processing apparatus are configured integrally or separately. It is characterized by that.

  In the embodiment described later, the sheet processing apparatus is the sheet post-processing apparatus 2, the image forming apparatus is the copying machine 1, the folding apparatus is the folding machine 3, the upper discharge tray is the upper discharge tray 321, and the lower discharge tray is the lower discharge tray 321. The side discharge tray is the lower discharge tray 301, the moving means is the first vertical motor 162 and the second vertical motor 157, the first paper surface detection means is the paper surface detection filler 341 and the paper surface detection sensor S1, and the second. The paper surface detection means is biased to the filler 311 and the paper surface detection sensor S2, the storage means is biased to the end fence 331 and the support member 312b, the support member supporting the filler is biased to the support member 312b and the shaft 312c, and the return roller is biased to the reference numeral 312a. The means is the spring 316, the means for interlocking the filler with the rotation of the support member is the ribs 314, 315, the control means is the CPU 150, and the discharge port is 2 Corresponding respectively to 9.

According to the present invention, when the upper discharge tray is at the discharge position, the detection member is retracted to the inside of the end fence by the upper discharge tray so as not to come into contact with the upper discharge tray. In addition, it is possible to improve the sheet alignment of the upper discharge tray .

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing a system configuration of an image forming system according to an embodiment of the present invention. As shown in FIG. 1, an image forming system according to this embodiment includes a digital copying machine (multifunction machine) 1 as an image forming apparatus having a plurality of functions such as a printer, a copy, and a facsimile, and the digital copying machine 1. A sheet post-processing apparatus 2 as a sheet processing apparatus that performs post-processing such as stipple processing, folding processing, and sorting processing on a sheet ejected from an image and having an image formed thereon, and the copier 1 and the sheet post-processing apparatus 2 and a folding machine 3 capable of performing Z-folding on the paper discharged from the copying machine 1. The folding machine 3 is configured separately from the copying machine 1 on the paper discharge side, and is attached via a paper discharge port (not shown) of the copying machine. The sheet post-processing device 2 is configured separately from the folder 3 and is attached via a paper discharge port of the folder 3.

  The sheet post-processing apparatus 2 is provided with an upper conveyance path 210, a middle conveyance path 220, and a lower conveyance path 240. The upper transport path 210 guides paper to the proof tray 214, the middle transport path 220 guides paper to the upper discharge tray 321 or the lower discharge tray 301, and the lower transport path 240 passes through the staple tray 402 to the upper discharge tray. 321 or the lower paper discharge tray 301 is led. On the downstream side of the staple tray 402, a folding plate 466 and folding rollers 451 and 452 are provided across the paper discharge path from the staple tray 402, and the saddle stitched sheets are folded and discharged to the lower paper discharge tray 301. Make paper.

  The staple tray 402 is provided with a rear end fence 410, an end binding stapler 401, a saddle stitching stapler 403, and a discharge belt (not shown). The rear end fence 410 is provided at the rear end portion (upstream side in the paper transport direction) of the staple tray 402, and further binds the paper end portion with the rear end fence 410 restricting the rear end of the sheet bundle. An end binding stapler 401 is provided at a position where the image can be printed. Further, the saddle stitching stapler 403 is provided at a position higher than at least the central portion of the paper size to be folded when the paper bundle is regulated by the rear end fence 410, and the discharge belt (not shown) provided on the discharge belt. The rear end portion of the sheet bundle is pushed up by the nail, the center of the sheet is positioned at the binding position of the saddle stitching stapler 403, and this state is maintained to enable the saddle stitching.

  The folding plate 466 pushes the saddle stitching position (center portion) of the sheet bundle into the nip of the folding pair rollers 451 and 452, folds the pair of folding rollers 451 and 452, and discharges the paper to the lower discharge tray 301. As shown by a two-dot chain line in FIG. 1, the lower discharge tray 301 is lowered from the upper position to a position further lower than the position indicated by the solid line so that discharged sheets or sheet bundles can be stacked as much as possible. Yes. Selection of the conveyance direction of the sheet to the upper conveyance path 210, the middle conveyance path 220, and the lower conveyance path 240 is performed by the switching operation of the first and second branch claws 231 and 221.

  That is, the first branching claw 231 is provided at a branching portion from the entrance conveyance path to the upper conveyance path 210 following the middle conveyance path 220 and is guided to the upper conveyance path 210 when rotated in the clockwise direction in the figure. When it is rotated counterclockwise in the drawing, it is guided to the middle conveyance path 220 or the lower conveyance path 240, and the second branch claw 221 is rotated clockwise to the lower conveyance path 240 when it is rotated counterclockwise. When this happens, the paper transport direction is switched to the middle transport path 220.

  In addition, the entrance roller 202 and the transport roller 203 are provided in the entrance transport path, the transport rollers 212 and 213 are provided in the upper transport path, the transport roller 222 and the discharge roller 211 are provided in the middle transport path 220, and the lower transport path 240 is provided in the lower transport path 240. A plurality of transport rollers 241 and a staple paper discharge roller 242 are provided. The paper discharge roller 211 includes a driving roller on the lower side of the drawing and a driven roller provided on the free end side of the paper discharge guide plate 231. The paper discharge guide plate 231 is swingable around a support shaft as described later. And is driven to swing by a link mechanism.

  The digital copying machine 1 includes an automatic document feeding unit (ADF) (not shown), a scanner unit, a writing unit, an image forming unit, and a paper feeding unit. The document fed by the ADF is read by the scanner unit and read. Paper (recording medium) that is optically written on the photoconductor of the image forming unit based on the image information, develops the latent image formed by optical writing with the image forming unit, is visualized, and is sent from the paper feeding unit Then, the image is fixed and sent to the paper post-processing apparatus 2. Since the image forming unit forms an image based on a known electrophotographic image forming process, detailed description thereof is omitted here. The image information may be not only captured from the scanner but also sent directly from the computer or indirectly via the network, and can be processed in the same manner as that read by the scanner. Is possible.

  In the image forming system configured as described above, the peripheral sheet discharged from the copying machine 1 main body is transported to the folding machine 3 after the presence or absence of the sheet folding process is selected in the operation unit of the copying machine 1 main body, and the folding process is performed. Or the sheet is conveyed to the sheet post-processing apparatus 2 without being folded. The sheet conveyed from the folding machine 3 is carried into the entrance guide plate 201 of the sheet post-processing apparatus 2 and is conveyed into the sheet post-processing apparatus 2 by the conveying rollers 202 and 203.

  When the non-stipple mode is selected in the operation unit (not shown) of the copying machine 1 main body, the sheet passes through the first and second branching claws 231 and 221 and is guided to the middle conveyance path (non-stipple conveyance path) 220. The paper is discharged and stacked on the upper discharge tray 321 or the lower discharge tray 301. At this time, the paper discharge guide plate 231 is in a closed state, that is, in the state shown in FIG. Further, the first and second branch claws 231 and 221 are in an initial state, and in the initial state, the middle conveyance path 220 is open.

  When the interruption (proof) tray discharge mode is selected on the operation unit of the digital copying machine 1, the first branching claw 231 is activated to select the upper conveyance path (interrupt tray conveyance path) 210 side, and the sheet is proofed. The paper is discharged to the tray 214.

  When the staple mode is selected in the operation unit of the digital copying machine 1, the second branching claw 221 operates to select the lower conveyance path (stipple conveyance path) 240 side, and the sheet is guided to the lower conveyance path 240. Further, the paper is discharged from the staple discharge roller 242 to the staple tray 402 via the transport roller 241. The sheets discharged to the staple tray 402 are dropped one by one by the tapping roller 250 toward the trailing edge fence 410, and the trailing edges of the sheets (paper conveying direction) are aligned. Subsequently, the jogger fence 422 performs alignment in the direction orthogonal to the sheet conveyance, and the sheets are stacked with the sheet conveyance direction and the direction orthogonal to the sheet conveyance direction aligned for each sheet. As a result, the aligned sheet bundle is stacked on the staple tray 402.

  In the staple mode, when the paper discharge guide plate 231 is opened around the support shaft and the trailing edge of the paper is selected, after the final paper is aligned by the jogger fence 422 The edge binding stapler 401 performs one or two binding processes at a predetermined position at the rear end of the sheet bundle. The bound sheet bundle is pushed up to the position of the sheet discharge roller 211 by a discharge claw provided integrally with the discharge belt, stops and then closes, and the driven roller drives the sheet bundle by its own weight of the guide plate 231. Press toward the roller. As a result, a conveying force is applied to the sheet bundle, and the sheet is discharged onto the upper discharge tray 321 or the lower discharge tray 301. The paper discharge guide plate 231 is driven to swing around the support shaft by a link driven by a cam (not shown), and can take two positions, an open state and a closed state. The cam is driven by a motor (not shown), and the paper discharge guide plate 231 is swung.

  The upper paper discharge tray 321 and the lower paper discharge tray 301 are provided so as to be movable up and down by independent drive mechanisms (not shown), and can be moved to the paper discharge position of the paper discharge roller 211, respectively. As a result, the upper paper discharge tray 321 or the lower paper discharge tray 301 can be moved according to the selected mode to switch the tray on which the paper is stacked.

  FIGS. 2 to 5 are views for explaining a mechanism for moving the upper discharge tray 321 up and down. FIG. 2 is a front view showing a main part of a drive mechanism for the upper discharge tray 321. FIG. 3 is a main part of FIG. FIG. 4 is a plan view, FIG. 4 is a diagram showing a moving state of the upper paper discharge tray shown in FIG. 2, and FIG. 5 is a diagram showing a state when sheets are stacked and moved. In these drawings, the upper paper discharge tray 321 is fixed to a cradle 322. The cradle 322 is further fixed to a belt (not shown) and can be driven up and down as the belt moves. The cradle 322 is provided with a DC solenoid 325 (FIG. 3), a lever 326, a clutch 324, and a pinion gear 323, and an end fence 331 attached to the side surface of the sheet post-processing device 2 is a rack 333 and the rack 333. It is possible to move up and down integrally through a pinion gear 323 meshing with 333.

  When the DC solenoid 325 is off, the clutch 324 is configured to rotate only in the direction indicated by the arrow in FIG. 2, so that the end fence 331 is prevented from moving by its own weight in the downward direction by the rack 333 and the pinion gear 323, It is possible to move up and down while maintaining the positional relationship with the upper discharge tray 321. When the upper paper discharge tray 321 is not at the paper discharge position (when waiting above the paper discharge roller 211-FIG. 5 ... two-dot chain line position), or from this standby position, the paper discharge position (FIG. 5 ... solid line position) ), Or when the DC solenoid 325 is off, the upper discharge tray 321 and the end fence 331 move up and down together. On the other hand, when the DC solenoid 325 is turned on, the lever 326 is pulled and the lock of the clutch 324 is released. As a result, the pinion gear 323 becomes rotatable in both directions, and there is no element that prevents the end fence 331 from moving downward, and the pinion gear 323 becomes movable in the vertical direction.

  When the upper discharge tray 321 moves downward from the standby position, the DC solenoid 325 is off, the upper discharge tray 321 and the end fence 331 are lowered integrally, and the end fence 331 is discharged in advance. When it reaches the position, it stops by a stopper (not shown). However, after the upper discharge tray 321 is further lowered by a predetermined distance, the DC solenoid 325 is turned on and at the same time the clutch 324 is released, only the upper discharge tray 321 is raised, and the upper discharge tray 321 is detected by the paper surface detection sensor 332. When it is done, it stops. At that time, the DC solenoid 325 is also turned off. When the end fence 331 is stopped by the stopper, only the upper discharge tray 321 can be lowered by the locking direction of the clutch 324. This state is shown in FIG.

  When the sheets P are sequentially discharged to the upper discharge tray 321, a position at which the upper discharge tray 321 is detected by the paper surface detection sensor 332 at the same time when the sheet post-processing device 2 receives a sheet discharge signal from the copying machine 1. The sheet P is lowered downward by a predetermined distance from the sheet, stops at that position, receives the discharged sheet, the amount of the sheet P loaded on the upper discharge tray 321 increases, and the sheet surface detection sensor 332 detects the sheet surface. Then, the upper discharge tray 321 is further lowered by a predetermined amount. Further, the upper paper discharge tray 321 repeats the operation of raising the DC solenoid 325 to the position of the paper surface detection sensor 332 and lowering it by a predetermined distance for every predetermined number of sheets P to be detected. By this operation, the distance between the paper discharge position of the paper P by the paper discharge roller 211 and the upper surface of the uppermost paper is maintained. This state is shown in FIG. 5 described above.

  The surface detection of the sheets stacked on the lower discharge tray 301 is performed as follows. 6 is a view showing a state when paper is discharged to the upper paper discharge tray 321, FIGS. 7 and 8 are views showing an operation when the filler 311 is retracted, and FIG. 9 is swollen with the upper and lower paper discharge trays 321 and 301. FIG. 10 is a diagram showing a relationship with the paper, and FIG. 10 is a diagram showing a state when the filler 311 is retracted by the upper paper discharge tray 321.

  When a paper discharge signal for discharging paper from the copying machine 1 to the lower paper discharge tray 301 is received, if the upper paper discharge tray 321 is at the paper discharge position (state shown in FIG. 6), the upper paper discharge tray 321 is discharged. Ascending to the standby position above the roller 211, the lower discharge tray 301 also starts to rise to the discharge position (see FIG. 1). In the illustrated embodiment, when a paper discharge destination is switched, a predetermined position on the other end side of the paper surface filler 341 as the first paper surface detection means and the paper surface filler 341 is detected so that the upper paper discharge tray 321 and the lower paper discharge tray 301 do not interfere with each other. The paper surface detection sensor S1 detects the position of the paper surface, and moves up and down while keeping the distance between the paper surface of the lower paper discharge tray 301 and the upper paper discharge tray 321 constant.

  As shown in FIG. 7, when the lower end of the end fence 331 rises from the paper discharge position, the return roller 312a, which is a conveying means in a retracted state supported rotatably by the support member 312b as shown in FIG. It turns around the axis 312c and protrudes to a predetermined position. The return roller 312a has a function of returning the paper P to the end fence 319, and has a function of performing alignment in the paper transport direction together with the rear end fence 401. The filler 311 as the second paper surface detection means is hooked on the lip 314 provided on the support member 312b of the return roller 312a and protrudes to a position where the lower paper discharge tray 301 can be detected. Thereafter, the lower sheet discharge tray 301 that has risen is detected when the sheet surface detection sensor S2 detects that the filler 311 has reached the position corresponding to the sheet discharge position by the sheet surface detection sensor S2 that detects the positions of the filler 311 and the filler 311. Stop and accept paper. The filler 311 is also rotatably supported by the shaft 312c.

  When the sheets are sequentially discharged to the lower discharge tray 301, the lower discharge tray 301 receives the sheet discharge signal from the copying machine 1 main body, and at the same time, the lower discharge tray 301 detects the position of the sheet surface detection sensor S2 (in FIG. When the paper edge detection sensor S2 detects that the trailing edge of the discharged paper is detected by the paper surface detection sensor S2, the paper surface detection sensor S2 end is lowered downward from the paper surface detection sensor S2). Move down the distance. Further, the lower discharge tray 301 repeats rising to a detection position of the paper surface detection sensor S2 and lowering by a predetermined distance for every predetermined number of discharged sheets. By this operation, the distance between the paper discharge position by the paper discharge roller 211 and the paper stacking surface position is maintained within a predetermined range. When performing the folding process, when the print job is finished, the lower paper discharge tray 301 is lowered by a certain amount and stopped in order to separate the paper surface from the upper paper discharge tray 321 so that the paper can be easily taken out.

  When receiving a paper discharge signal to be discharged from the copying machine 1 main body to the upper paper discharge tray 321, the lower paper discharge tray 301 and the upper paper discharge tray 321 are connected to the lower paper discharge tray by a paper surface filler 341 and a paper surface detection sensor S 1 (not shown). The position of the paper surface on 301 is detected, and as shown in FIG. 9, it begins to descend while maintaining a certain distance. Then, as shown in FIGS. 7 and 10, when the upper discharge tray 321 is lowered, the rear end of the end fence 331 comes into contact with the rib 315 of the return roller 312 and further pressed down, whereby the return roller 312 and the filler 311 are moved into the machine. The upper discharge tray 321 is stored, and stops at the upper discharge position shown in FIG. At this position, a lower limit sensor SE2 is provided, and the lower limit sensor SE2 stops at the position where the rear end of the end fence 331 of the upper discharge tray 321 is detected. Note that the highest position of the upper discharge tray 321 is a position where the upper end of the end fence 331 is detected by the upper limit sensor SE1, as shown in FIG.

  The operations based on the relationship between the upper and lower discharge trays 321 and 301 and the tray position sensor are substantially as described above. However, the control operation differs depending on the presence or absence of Z-folding and the presence or absence of binding. Therefore, the control procedure corresponding to the presence or absence of Z-folding and the paper discharge tray for paper discharge is shown in the flowchart of FIG. 11, and the operation at this time will be described.

  The user inputs whether to perform Z-folding and whether to perform binding from an operation panel (not shown) of the copying machine 1 main body. When Z-folding is performed by this operation input (step S100), the upper discharge tray 321 is moved to the upper limit sensor SE1 (retraction position) when a signal for paper processing is received from the main body of the copying machine 1 regardless of the presence or absence of binding. (Step S101). In this case, if the upper limit sensor SE1 detects the upper discharge tray 321, the state is maintained as it is. In other words, if it is already in the retracted position, that position is maintained. This is the state of the upper discharge tray 321 indicated by the solid line in FIG. Then, the upper surface of the lower paper discharge tray 301 is raised through the filler 311 until the paper surface sensor S2 detects it (step S102). Next, paper discharge is accepted, a job completion notification is received from the copying machine 1 main body, and after the last sheet or sheet bundle is discharged to the lower discharge tray 301, the lower discharge tray 301 is lowered by a preset amount. (Step S103), return and prepare for the next job.

  On the other hand, in the staple mode or non-staple mode without Z-folding (S110), the processing differs depending on whether the discharge destination is set to the upper discharge tray 321 or the lower discharge tray 301. Therefore, it is checked whether the discharge destination is set to the upper discharge tray 321 or the lower discharge tray 301 (step S111), and if the discharge destination is set to the upper discharge tray 321. Further, it is checked whether or not the upper limit sensor SE1 detects the upper discharge tray 321 (step S112). When the upper limit sensor SE1 does not detect the upper discharge tray 321 and it is not known where the upper discharge tray 321 is, the lower limit sensor SE2 receives the discharge destination signal from the main body of the copying machine 1 and receives the upper discharge sensor 321. The upper paper discharge tray 321 is lowered to a position where the tray 321 is detected (step S113). Next, the upper discharge tray 321 is raised to a position where the paper surface detection sensor 332 detects the upper surface of the upper discharge tray 321 (step S114), and the process returns. Then, this position becomes the paper receiving position, and the reception of the paper or the paper bundle is waited at this position (position in FIG. 6).

  On the other hand, when the upper limit sensor SE1 detects the upper discharge tray 321 and the upper discharge tray 321 is in the retracted position (position detected by the upper limit sensor SE1) in step S112, the upper discharge sensor 321 passes through the upward stroke as described above. As an initial state, the paper tray 301 is in a paper discharge port position (FIG. 1-2, chain line position). In this case, when a paper discharge destination signal is received from the copying machine 1 main body, both the upper paper discharge tray 321 and the lower paper discharge tray 301 are lowered and stopped at a position where the lower limit sensor SE2 detects the upper paper discharge tray 321 ( Step S115). Next, the upper discharge tray 321 is raised to a position where the paper surface detection sensor 332 detects the upper surface of the upper discharge tray 321 (step S116), and the process returns. Then, this position becomes the paper receiving position, and the reception of the paper or the paper bundle is waited at this position (position in FIG. 6).

  If the paper discharge destination is not the upper paper discharge tray 321 in step S111, the lower paper discharge tray 301 is set as the paper discharge destination. Therefore, if the lower discharge tray 301 is set, the upper discharge tray 321 is raised to the upper limit sensor SE1 (retracted position) when the discharge destination signal is received from the copying machine 1 main body (step S117). In this case, if the upper limit sensor SE1 detects the upper discharge tray 321, the state is maintained as it is. In other words, if it is already in the retracted position, that position is maintained. This is the state of the upper discharge tray 321 indicated by the solid line in FIG. Then, the upper surface of the lower paper discharge tray 301 is raised through the paper filler 341 until the paper surface sensor S1 detects it (step S118), and the process returns. Then, this position becomes the paper receiving position, and the reception of the paper or the paper bundle is waited at this position (FIG. 1-2, dotted line position).

  The position of the paper discharge tray that receives the paper discharged from the paper discharge port (the paper discharge port from which the paper is discharged from the paper discharge roller 211) according to the selected mode and the selected paper discharge tray. Is controlled.

  In order to realize such an operation, the image forming system according to the present embodiment is configured as shown in FIG. FIG. 12 is a block diagram showing the electrical configuration of the image forming system according to this embodiment including the image forming apparatus 1 and the post-processing apparatus 2. Here, the electrical configuration of the sheet post-processing apparatus 2 is mainly shown here. Show.

  The sheet post-processing apparatus 2 is provided with a CPU 150 and an I / O 151, and the CPU 150 and the I / O 151 are connected by a bus. The CPU 150 is connected to a control device (CPU) of the image forming apparatus 1 and controls each part and the whole of the sheet post-processing apparatus 2.

  The CPU 150 has a solenoid 153, 154, 155, a first vertical motor 162 that raises and lowers the upper paper discharge tray 321, a second vertical motor 157 that raises and lowers the lower paper discharge tray 301, and a shift that shifts the upper paper discharge tray 321. A motor 165, an entrance roller 202, a transport motor 158 that drives the transport rollers 203, 212, and 213, and a paper discharge motor 159 that drives the transport roller 222 and transports the paper to the paper discharge position are connected. Further, the I / O 151 includes a staple motor 160 that performs an operation of binding a sheet bundle by the end-face stitching stapler 401 and the saddle stitching stapler 403, a discharge motor 161 that discharges the sheet or the sheet bundle from the discharge (release) roller 211, and an end face. Staple moving motor 213 for moving the binding stapler 401, jogger motor 163 for performing the alignment operation of the paper in the direction orthogonal to the paper direction by the jogger fence 422, and angle change for driving the cam 234 for changing the angle of the paper discharge guide plate 231. A motor 223 is connected to output a drive signal from the CPU 150. The I / O 151 receives signals from the SWs including the sensors and the switch 254 and transmits the signals to the CPU 150. Each motor is provided with a motor driver 156 in the preceding stage, and the clock generated by the clock generation IC 164 is input to the transport motor 158 and the paper discharge motor 159. Further, a driving clock is input from the CPU 150 to each motor driver 156 to the staple moving motor 213, the jogger motor 163, and the angle changing motor 223.

  As described above, according to the present embodiment, there are the following effects.

1) By detecting the trailing edge of the paper that has not been swollen by folding processing with a filler (second paper surface detection means) 311, the paper surface stacked on the upper paper discharge tray 321 or the lower paper discharge tray 301 becomes the paper discharge port. On the other hand, it is possible to prevent the sheet from being lowered too much, and this makes it possible to improve the sheet alignment.

2) In the case of having the discharge trays 321 and 301 that can be switched up and down, it is necessary to provide a space in the upper discharge tray unit that does not come into contact with the filler (second paper surface detecting means) 311 when the upper discharge tray 321 is in the discharge position. Because of this space, the machine has to be large, but when the upper paper discharge tray 321 is in the discharge position, the filler 311 is stored in the machine so as not to come into contact with the upper paper discharge tray 321. The machine can be downsized.

3) When the filler 311 is stored as described above, if the stored filler 311 does not return to a predetermined position, the sheet surface of the sheet folded when the lower discharge tray 301 comes to the discharge position. Cannot be detected, and the lower discharge tray 301 rises abnormally. Therefore, the stored filler 311 is returned to a predetermined position (the lower discharge tray can be detected) before the lower discharge tray 301 reaches the discharge position. Can be prevented.

4) When the filler 311 and the return roller 312 are stored at the same time when the upper paper discharge tray 321 is at the paper discharge position, means for returning to a predetermined position is provided in each of the filler 311 and the return roller 312. The machine configuration becomes complicated. Therefore, when the upper paper discharge tray 321 is at the paper discharge position and the filler 311 and the return roller 312 are stored at the same time, when either one returns from the stored state to a predetermined position, the other is also interlocked with the predetermined value. Return to the position. Thereby, the machine configuration can be simplified.

5) When folded sheets are stacked on the lower discharge tray 301, the gap between the upper discharge tray 321 is narrowed after the job is completed, and it may be difficult to remove the sheets. Therefore, when a folded sheet is stacked on the lower discharge tray 301, the lower discharge tray 301 is lowered after the job is completed. As a result, the interval between the paper and the upper paper discharge tray 321 is increased, and the paper can be easily taken out.

1 is a diagram illustrating a system configuration of an image forming system according to an embodiment of the present invention. FIG. 3 is a front view illustrating a main part of a drive mechanism for an upper discharge tray in the embodiment of the present invention. It is a principal part top view of FIG. FIG. 3 is a diagram illustrating a moving state of an upper discharge tray illustrated in FIG. 2. FIG. 3 is a diagram illustrating a state when sheets on the upper discharge tray illustrated in FIG. 2 are stacked and moved. FIG. 6 is a diagram illustrating a state where an upper discharge tray is positioned at a discharge outlet and a sheet is discharged to the upper discharge tray. It is a figure which shows operation | movement when retracting | saving a filler. It is the figure which expanded the principal part of FIG. FIG. 6 is a diagram illustrating the relationship between the position of the upper and lower discharge trays and the swollen paper. FIG. 6 is a diagram illustrating a state when a filler is retracted by an upper discharge tray. 5 is a flowchart showing a control procedure corresponding to the presence or absence of Z-folding and a paper discharge tray for paper discharge. 1 is a block diagram illustrating an electrical configuration of an image forming system according to the present embodiment including an image forming apparatus 1 and a post-processing apparatus 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copying machine 2 Paper post-processing apparatus 3 Folding machine 150 CPU
157 Second vertical motor 162 First vertical motor 219 Paper outlet 301 Lower paper output tray 311 Filler 312a Return roller 312b Support member 312c Shaft 314, 315 Rib 316 Spring 321 Upper paper output tray 331 End fence 341 Paper surface detection filler

Claims (2)

At least two discharge trays, an upper discharge tray and a lower discharge tray, which can move up and down for stacking paper;
Moving means for moving these discharge trays up and down along the end fence on the side of the apparatus;
First paper surface detection means for detecting a positional relationship between the upper discharge tray and the lower discharge tray;
A paper processing device having a second paper surface detecting means for detecting a rear end of the paper stacked on the lower paper discharge tray;
A return roller for returning the paper discharged to the lower discharge tray to the end fence side;
A paper discharge roller for discharging the two paper discharge trays ;
A support member for rotatably driven supported at one end a pre-Symbol return roller,
A first end protruding from the outer periphery of the return roller and contacting the upper surface of the lower discharge tray or the paper surface on the lower discharge tray, and a second position for detecting the rotational position of the first end. A detection member as the second paper surface detection means having an elongated shape having an end of
Inside the end fence, the support member is rotatably supported by an end portion opposite to the end portion on the return roller support side, and the detection member is supported by the first and second end portions. Shaft means for swingably supporting between,
Biasing means for resiliently biasing the support member so that the return roller protrudes from the end fence to a predetermined position on the side surface of the apparatus;
When the return roller is protruded from the end fence by the rotation of the support member, the detection member is protruded in conjunction with the rotation of the support member and stored in the same manner when stored inside the end fence. Interlocking means,
With
When the upper discharge tray is at the discharge position, the lower end portion of the upper discharge tray comes into contact with a predetermined position on the upper surface of the support member protruding from the end fence by the lowering operation of the upper discharge tray. A sheet processing apparatus, wherein the supporting member is rotated with respect to the shaft against an elastic urging force of an urging means, and the return roller and the detection member are stored in an apparatus inside the end fence. A sheet processing apparatus according to claim 1;
An image forming apparatus for forming a visible image on a recording medium and discharging the sheet to the sheet processing apparatus;
Is formed as a single body or as a separate body.

Images