JP2007261700A - Sheet treatment device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stop treatment action of a sheet folding device on a downstream side by detecting excessive load when the excessive load is generated on a stapler on an upstream side by an almost existing mechanism without adding almost a new mechanism. <P>SOLUTION: The sheet treatment device 2 folds/bends the bundle of sheets by the sheet folding device 60 after the bundle of sheets is stapled by the staplers 18A, 18B. The sheet treatment device 2 stops the sheet folding action of the sheet folding device by CPU 150 when a staple current value detected by a current detection mechanism for detecting the load in stapling by the staplers 18A, 18B is a predetermined value or more. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention provides a sheet processing apparatus that prevents damage to the apparatus by stopping subsequent downstream processing when an excessive load occurs in upstream processing when processing different sheets sequentially. And an image forming apparatus provided with the sheet processing apparatus in the apparatus main body.

  2. Description of the Related Art Conventionally, an image forming apparatus that forms an image on a sheet includes a sheet processing apparatus that performs at least two processes among a process of aligning, binding, bending, and punching a sheet on which an image is formed. There is something that is. For example, there is a sheet processing apparatus in which a sheet is bound by a stapler, and then the sheet is folded in half by a folding apparatus to be folded into a booklet.

  In this case, the sheet folding apparatus may be difficult to bend if the number of sheets to be folded is large. Therefore, whether or not folding processing can be performed in the sheet processing apparatus or the apparatus main body of the image forming apparatus based on the number of sheets bound by the user input to the apparatus main body of the image forming apparatus to which the sheet processing apparatus is connected. Was judging.

  However, if the user incorrectly inputs the number of sheets to be bound and the sheet thickness information, the user may not be able to perform an accurate folding process. Therefore, there is a sheet processing apparatus that counts the number of sheets without depending on user input information, further detects the thickness of the sheet, and determines whether to process the sheet (see Patent Document 1).

JP-A-9-278269

  However, the conventional sheet processing apparatus has a problem that the cost increases because hardware for detecting the thickness of the sheet is added. Further, when the determination is made only by counting the number of sheets, there is a problem that variations due to the thickness of each sheet cannot be absorbed.

  Also, the cost of an image forming apparatus provided with a conventional sheet processing apparatus has been increased.

  In the present invention, when an overload occurs in the upstream processing means with almost existing mechanisms without adding a new mechanism, the overload is detected and the processing operation of the downstream processing means is stopped. It is to provide a processing apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that is provided with a sheet processing apparatus that prevents an increase in cost, and that reduces costs.

  The sheet processing apparatus according to the present invention is configured such that after the sheet bundle is subjected to the first processing operation by the first processing means, the sheet bundle is subjected to the second processing operation by the second processing means. Load detecting means for detecting a load during the first processing operation, and stop means for stopping the second processing operation of the second processing means when the load detected by the load detecting means is equal to or greater than a predetermined value. It is characterized by having.

  An image forming apparatus according to the present invention includes: an image forming unit that forms an image on a sheet; and a sheet processing device that processes a sheet on which an image is formed by the image forming unit, and the sheet processing device performs the sheet processing described above. It is a device.

  In the sheet processing apparatus of the present invention, when an overload occurs in the existing first processing unit, the overload is detected, the processing operation of the second processing unit on the downstream side is stopped, and the second processing unit is damaged. Can be prevented.

  Accordingly, since the sheet processing apparatus of the present invention uses the existing first processing means, it is possible to prevent the second processing means from being damaged with a simple structure. Furthermore, an increase in cost can be prevented.

  Since the image forming apparatus of the present invention includes a simple sheet processing apparatus, the overall structure does not become complicated.

  Hereinafter, a sheet processing apparatus according to the present embodiment and an image forming apparatus including the sheet processing apparatus in the apparatus main body will be described with reference to the drawings. The sheet processing apparatus is installed as a purchase option (so-called option) in the apparatus main body of the image forming apparatus that forms an image on a sheet, but may be built in the apparatus main body.

  Note that the shape, relative arrangement relationship, numerical values, and the like of the components described in the embodiments do not limit the present invention.

(Image forming device)
FIG. 6 is a schematic cross-sectional view of the image forming apparatus according to the embodiment of the present invention, for example, along a sheet conveying direction of a copying machine. Examples of the image forming apparatus include a copying machine, a printer, a facsimile, and a complex machine of these, and the image forming apparatus of the present invention is not limited to the copying machine.

  The apparatus main body 10 of the copying machine 1 includes a platen glass 906 as a document placement table, a light source 907, a lens system 908, a sheet supply unit 909, an image forming unit 902, and the like.

  The sheet supply unit 909 stores cassettes for recording and is detachably attached to the apparatus main body 10, a deck 913 disposed on the pedestal 912, a pickup roller (not illustrated) that feeds the sheet to the image forming unit 902, and the like. have. The image forming unit 902 includes a cylindrical photosensitive drum 914, a developing unit 915, a transfer charger 916, a cleaner 918, a primary charger 919, and the like disposed around the drum. On the downstream side of the image forming unit 902, a conveying device 920, a fixing device 904, a pair of discharge rollers 1a and 1b, and the like are disposed.

  When a sheet supply signal is output from the control device 930 provided in the apparatus main body 10 of the copying machine 1, the sheet P is supplied from the cassettes 910 and 911 or the deck 913. On the other hand, the light reflected from the light source 907 on the document D placed on the platen glass 906 is applied to the photosensitive drum 914 through the lens system 908. The photosensitive drum 914 is charged in advance by a primary charger 919. When light is irradiated, an electrostatic latent image is formed, and then the electrostatic latent image is developed by a developing device 915 to form a toner image. The

  The sheet P fed from the sheet feeding unit 909 is skew-corrected by the registration roller pair 901, further aligned with the toner image, and fed to the image forming unit 902. In the image forming unit 902, the toner image on the photosensitive drum 914 is transferred to the sheet P that has been sent by the transfer charger 916. The sheet P to which the toner image has been transferred is charged to a polarity opposite to that of the transfer charger 916 by the separation charger 917 and separated from the photosensitive drum 914.

  The separated sheet P is conveyed to the fixing device 904 by the conveying device 920, and the transferred image is permanently fixed by the fixing device 904. The sheet S on which the image is fixed is discharged from the apparatus main body 10 of the copying machine 1 by the discharge roller pair 1a and 1b. In this way, the sheet P fed from the sheet feeding unit 909 forms an image and is discharged.

(Sheet processing equipment)
FIG. 1 is a cross-sectional view of the sheet processing apparatus along the sheet conveyance direction. FIG. 2 is a front view of the stapler unit.

  First, the sheet processing apparatus 2 of the present invention will be outlined. The sheet processing apparatus 2 bundles sheets discharged from the apparatus main body 10 of the copying machine 1 by the discharge roller pairs 1a and 1b, and is a first processing means and a binding means such as staplers 18A and 18B. For example, a staple binding operation for binding a sheet bundle is performed. Thereafter, the sheet processing apparatus 2 performs, for example, a folding operation for folding, for example, a second processing operation on the sheet bundle by the sheet folding device 60 that is the second processing unit and the folding unit. As a result, the sheet processing apparatus 2 can make the sheet bundle into a booklet shape.

  In this processing operation, the load current values (staple current values) of the motors 210 and 213 during the staple binding operation of the staplers 18A and 18B are measured by, for example, current detection mechanisms 251 and 252 which are load detection means. The CPU 150 that is the stopping means determines whether or not the load current value is equal to or greater than a threshold value. The stapler current value increases as the thickness of the sheet bundle increases. The threshold value is set to a stapler current value at which the sheet folding device 60 may be damaged when the sheet folding device 60 bends a sheet bundle having a thickness greater than this. The threshold value may be changed between a sheet that is easy to bend and a sheet that is difficult to bend.

  When the CPU 150 determines that the stapler current value is equal to or greater than the threshold value, the CPU 150 stops the operation of the sheet folding device 60 so that the sheet folding device 60 does not perform the folding operation.

  As a result, the sheet processing apparatus 2 can detect the overload of the existing staplers 18A and 18B and prevent the sheet folding apparatus 60 from being damaged.

  The sheet processing apparatus 2 of the present embodiment has two staplers, but may have only one, or three or more. Further, instead of the staplers 18A and 18B, a punching device for making holes in the sheet bundle may be provided, and a cutting device for cutting the sheet bundle may be provided instead of the sheet folding device 60.

  Hereinafter, the sheet processing apparatus 2 will be described in detail.

  The entrance flapper 3 selects either the bookbinding mode or the stack mode according to the rotation thereof. The paper discharge guide 4 guides sheets in the stack mode. The stacker discharge roller 5 and the stacker discharge roller 6 are provided on the downstream side of the paper discharge guide 4 in a state where they are arranged vertically. The stacker tray 7 is configured to stack sheets discharged from the stacker discharge port roller 5 and the stacker discharge rollers 6.

  The guides 11 and 12 are guides for guiding the sheet in the stack mode downward. The conveyance roller 13 is disposed on the guides 11 and 12, and the conveyance roller 14 is in press contact with the opposing surface. The conveyance roller 13 and the conveyance roller 14 form a sheet introduction unit that conveys the sheet to the sheet positioning member 23. The upper and lower switching flappers 15 and 16 take two positions shown in the figure by upper and lower switching solenoids 15d and 16d. The half-moon rollers 17a and 22a are urged by elastic members 17d and 22d arranged to face each other.

[Stapler unit]
In FIG. 2, the stapler unit 18 has a front stapler 18A and a back stapler 18B arranged in a direction intersecting the sheet conveying direction (sheet width direction). The front stapler 18A is disposed on the front side, and the back stapler 18B is disposed on the back side. In FIG. 2, the back stapler 18B is not shown because it does not overlap the front stapler 18A. Since the back stapler 18B and the front stapler 18A have the same structure, only the front stapler 18A will be described, and the description of the back stapler 18B will be omitted.

  The front stapler 18A is filled with plate-shaped staples. The front stapler motor 210 of the front stapler 18 </ b> A transmits rotation to the eccentric cam gear 102 via the gear 101. The eccentric cam gear 102 is integrally provided with an eccentric cam (not shown). A stapling operation is performed once when the eccentric cam rotates once.

  A sensor flag (not shown) is attached to the eccentric cam shaft 103. This sensor flag rotates with the eccentric cam when the front stapler motor 210 is started, turns off the front stapler motor home position (HP) sensor 211 (see FIG. 4), which is normally in the ON state, and again after one rotation. Turn it on. When the sensor 211 is turned on, the front stapler motor 210 stops and one stapling operation is completed. During this stapling operation, the staple current value that flows to the front stapler motor 210 is detected by the front current detection mechanism 251 (see FIG. 4) and reported to the CPU 150.

  When the eccentric cam (not shown) starts to make one rotation, the front end 18Aa of the near side stapler 18A located farthest from the anvil 19 approaches the anvil 19 around the rotation shaft 18a. The front end 18Aa of the front stapler 18A and the anvil 19 bind the sheet bundle by passing the staple needle through the sheet bundle and crushing the front end of the staple needle onto the glasses. Thereafter, the front end 18 </ b> Aa of the front stapler 18 </ b> A moves away from the anvil 19 and stands by at the farthest position.

[Sheet positioning mechanism]
In FIG. 1, guides 20 and 21 disposed on the downstream side of the stapler unit 18 guide the sheet to the sheet positioning member 23. The sheet positioning member 23 receives the lower end of the sheet and temporarily stacks the sheet. The sheet positioning member 23 is moved up and down between the guides 20 and 21 in the direction of the arrow in the figure, and the staple point 19a for binding the stacked sheet bundle by the stapler unit 18 and the folding point for folding the sheet bundle by the sheet folding device 60. 60a is positioned. The sheet positioning member 23 is moved up and down by guiding rollers 23 a provided on both sides along the sheet conveying direction to a groove (not shown) formed in the frame 8. Further, the sheet positioning member 23 is moved up and down by rotation of a pinion gear 23b that meshes with a rack 23e formed on the sheet positioning member 23 and rotates. The pinion gear 23 b is rotated by a sheet positioning motor 61. The sheet positioning member 23 is provided with a sheet leading edge detection sensor 33 that detects the leading edge of the sheet. A flag 23 f is formed below the sheet positioning member 23. When the flag 23f is detected by the sheet positioning motor home position sensor 63, the sheet positioning member 23 is lowered to the home position.

  The width adjusting members 24 a and 24 b are close to each other on both side ends of the sheets stacked on the sheet positioning member 23 so that the widths of the sheets are aligned. The width adjusting members 24a and 24b are arranged on the alignment motor H.264. The home position is detected by the P sensor 24e and moved by the width adjusting motor 24d.

[Sheet folding device]
The sheet folding apparatus will be described with reference to FIGS.

  A sheet folding device 60 for folding a sheet bundle will be schematically described. The folding sheet folding device 60 includes an ejection unit 25, folding roller pairs 26 and 27, and the like. The ejecting unit 25 projects the bound portion of the sheet bundle that is bound by the stapler unit 18 and is stacked on the sheet positioning member 23 and pushes it into the nip of the pair of folding rollers 26 and 27. The pair of folding rollers 26 and 27 are in pressure contact with each other, receive the sheet bundle projected by the ejection unit 25 at the nip, and bend while rotating and conveying.

  The sheet folding device 60 will be described in detail. The folding motor 64 has a pulley 65 attached to its output shaft. The idler gear pulley 67 is provided with two rows of pulleys and gears on the same axis. Among them, the timing belt 66 is wound between the pulleys in one row and the pulley 65. The folding gears 68 and 69 are attached to the folding roller pairs 26 and 27 and mesh with each other. The folding gear 69 meshes with the gear portion of the idler gear pulley 67.

  Since the protruding plate 25a moves into the nip between the pair of folding rollers 26 and 27 and enters, a stainless steel material having a thickness of about 0.5 mm is used. The protruding plate 25a is held by holders 25b and 25d. The holder 25b is attached to the shafts 25c and 25e. A roller (not shown) is rotatably mounted on the outer periphery, and the roller slides in a groove 8a formed in the frame 8.

  The gear 73 has a shaft 72 on one side surface and meshes with an idler gear 75. The idler gear 75 is attached to the shaft 76. The shaft 76 is provided with a protruding plate clutch 74a made of an electromagnetic clutch. The rotation of the pulley 74 is transmitted to the shaft 76 by ON / OFF of the protrusion plate clutch 74a.

  A timing belt 70 is wound around the outer periphery of the pulley 74, and the other side of the timing belt 70 is wound around an idler gear pulley 67. The idler gear 75 fixed to the shaft 76 meshes with the gear 73 fixed to the shaft 73a, and a flag (not shown) is fixed on the shaft 73a, and a notch is partially cut out. Have. The protruding plate home position sensor 82 is disposed at a position where the flag notch is detected, and is disposed so that the protruding plate 25a detects the position where the protruding plate 25a is depressed most from the conveying surface of the guide 21.

  The rotation of the folding motor 64 is transmitted from the pulley 65 to the idler gear pulley 67 via the timing belt 66. The rotation of the idler gear pulley 67 is transmitted from the folding gear 69 to the folding gear 68, and the folding roller pairs 27 and 26 are driven. On the other hand, the rotation of the idler gear pulley 67 is transmitted via the timing belt 70 to the pulley 74 on the protruding plate clutch 74a.

  The rotation of the pulley 74 is transmitted to the shaft 76 by the ON / OFF of the ejector plate clutch 74a, and the idler gear 75 rotates. The rotation of the gear 73 rotates by this rotation, and the shaft 72 moves circularly around the shaft 73a. .

  The link 71 having one end fitted to the shaft 72 has the other end fitted to the shaft 25c. The shaft 25c is mounted on the protruding unit 25, and further, a roller is inserted into the groove portion 8a of the frame 8 together with the shaft 25e, so that linear movement along the groove portion 8a is possible. By this linear motion, the ejection plate 25a provided in the ejection unit 25 is configured to reciprocate linearly between the ejection position and the retracted position.

[Sheet discharge mechanism]
The sheet discharge guide 28 is a plate-like member that is spaced apart from the upper and lower sides for guiding a sheet bundle discharged from folding rollers 26 and 27 of a sheet folding device 60 described later to a nip between the discharge roller 30 and the discharge roller 31. The paper discharge sensor 29 is an optical sensor that detects the front and rear ends of the sheet bundle. The discharge tray 32 is configured to stack the sheet bundle discharged from the discharge roller 30 and the discharge roller 31.

[Bookbinding Jam Processing Unit Mechanism]
In FIG. 1, the sheet processing apparatus 2 interrupts the bookbinding process when a sheet of a different size exists in the sheet bundle conveyed to the sheet positioning member 23 or a jam occurs. In some cases, the paper cannot be automatically discharged to the discharge tray 32. In such a case, the user needs to open the front door (not shown) of the sheet processing apparatus, open the openable door 303, and remove the sheet bundle from the conveyance path 301. The opening / closing door 303 can be opened clockwise (at the position of the dotted line) around the fulcrum 302. When the open / close door 303 is opened, the sheet bundle protrudes on the half-moon roller 17a, and the user can grasp and take out the sheet bundle by hand.

  FIG. 4 is a block diagram related to the control of the sheet processing apparatus.

  For example, the CPU 150 serving as the control means exchanges signals with the control device 930 provided in the apparatus main body 10 of the copying machine 1 by the communication means 231a. One of the CPU 150 and the control device 930 may be incorporated in the other.

  The CPU 150 is connected to a read only memory (ROM) 152 that stores in advance control procedures executed by the CPU 150. Also connected to the CPU 150 is a random access memory (RAM) 153 that stores various data such as operation data of the CPU 150 and control data received from the copying machine 1.

  The following sensors are connected to the input side of the CPU 150.

  A front stapler motor for detecting a staple strike standby position of the front stapler 18A. P sensor 211. A front stapler needle absence sensor 212 that detects the presence or absence of a needle in the front stapler 18A. Back stapler motor H. Detects the standby position of the back stapler 18B. P sensor 214. A back stapler needle absence sensor 215 that detects the presence or absence of a needle in the back stapler 18B. A conveyance path sensor 83 that detects that a sheet discharged from the apparatus main body 10 of the copying machine 1 has entered the sheet processing apparatus 2. A sheet leading edge detection sensor 33 that informs the CPU 150 that the sheet has arrived at a predetermined position of the sheet processing apparatus 2. A paper discharge path sensor 29 that detects that the sheet has been discharged to the discharge tray 32. A folding roller CLK sensor 216 for prompting the CPU 150 to control the speed of the pair of folding rollers 26 and 27. A roller guide motor for detecting the home position of the roller guide 201. P sensor 207. A sheet positioning motor for detecting the home position of the sheet positioning member 23; P sensor 63. An alignment motor home position sensor 24e that detects the home positions of the width adjusting members 24a and 24b that align sheets. A protruding plate home position sensor 82 for detecting the position of the protruding plate 25a. A half-moon roller sensor 217 that detects the rotational positions of the half-moon rollers 17a and 22a. A tray limit sensor 218 that detects an overload of the tray. A jam door switch 219 that detects the opening / closing of the jam handling door 303. A needle replenishing door switch 220 that detects opening and closing of the door for binding needle replacement replenishment processing or the like.

  The next motor, clutch, and solenoid are connected to the output side of the CPU 150 via the drivers D1 to D11.

  A conveyance motor 51 that rotates the conveyance roller 13 that conveys a copy sheet in the sheet processing apparatus and the half-moon rollers 17a and 22a. A roller guide motor 205 that moves a roller guide plate 201 for guiding a copy sheet in the sheet processing apparatus from a pair of folding rollers. A sheet positioning motor 61 that holds a sheet in the sheet processing apparatus at a specified position. A width adjusting motor 24d that moves the width adjusting members 24a and 24b to align the copy sheets in the sheet processing apparatus. A folding motor 64 for folding the sheet bundle in the sheet processing apparatus. A protruding plate clutch 74a for operating the protruding plate 25a. An upper switching solenoid 15d that operates an upper flapper 15 that switches a conveyance path in the sheet processing apparatus. A lower switching solenoid 16d that operates a lower switching flapper 16 that switches a conveyance path in the sheet processing apparatus. A front stapler motor 210 that drives the front stapler 18A for binding the sheet bundle. A back stapler motor 213 that drives the back stapler 18B that binds the sheet bundle. An inlet solenoid 3d for driving the flapper 3.

  Further, a front current detection mechanism 251 that converts the current flowing through the front stapler motor 210 into a digital signal and reports it to the CPU 150 as an input of the CPU 150 is connected. Also connected to the CPU 150 is a back current detection mechanism 252 that converts the current flowing through the back stapler motor 213 into a digital signal and reports it to the CPU 150.

  Next, FIG. 5 shows the staple current value of the front stapler motor 210 of the sheet processing apparatus 2 and the front stapler motor H. It is a graph which shows the relationship with the detection operation of P sensor 211.

  Normally, the front stapler motor 210 stands by at the home position, and the front stapler motor H.E. The P sensor 211 is in an ON state. When the front stapler motor 210 starts and rotates by a certain amount, the front stapler motor H.S. The P sensor 211 is turned off. Thereafter, the staple current value of the front stapler motor 210 changes in accordance with the load fluctuation when the front stapler unit 18A binds the sheet bundle. The staple current value is reported to the CPU 150 as data converted into a digital signal by the near current detection mechanism 251. Front stapler motor When the P sensor 211 is turned on again, the front stapler motor 210 stops.

  Back stapler motor 213, back current detection mechanism 252, back stapler motor H. The P sensor 214 also performs the same operation as described above.

[Bookbinding operation]
Sheet binding processing operation will be described based on the configuration diagrams of FIGS. 1 to 3 and 6, the control block diagram of FIG. 4, the staple current value change graph of FIG. 5, and the flowcharts of FIGS. 7 to 11. To do.

  The CPU 150 of the sheet processing apparatus 2 receives sheet information relating to the first sheet of the job from the control device 930 of the copying machine main body 10 through the communication unit 231a (S100). The sheet information is transmitted from the apparatus main body 10 of the copying machine 1 for each sheet. The sheet information includes information such as the sheet size code, the sheet type, post-processing designation, the first sheet of the job, and the last sheet.

  The sheet processing apparatus 2 determines whether the sheet carried in from the apparatus main body 10 of the copying machine 1 is in the bookbinding mode based on the previously received sheet information (S101). When not in the bookbinding mode, the inlet solenoid 3d remains OFF, and the inlet flapper 3 is tilted downward. The sheet is guided to the entrance flapper 3 and the conveyance guide 4 and discharged to the stack tray 7 (S401).

  If the sheet processing apparatus 2 determines in step S101 that it is in the bookbinding mode, it indicates that the previously received sheet is carried into the sheet processing apparatus 2 from the apparatus body 10 of the copying machine 1. 10 through the communication means 231a (S102).

  When it is reported to the sheet processing apparatus 2 that the sheet is loaded, the CPU 150 turns on the inlet solenoid 3d (S103). Then, the flapper 3 is switched to the bookbinding mode.

  Further, in order to convey the sheet carried in from the apparatus main body 10 of the copying machine 1 to the sheet positioning member 23, the conveyance motor 51 is turned on (starts rotating) (S104). In order to convey the sheet to the sheet positioning member 23 in the bookbinding mode, the CPU 150 moves the width adjusting members 24a and 24b waiting at the home position (HP) to the position where the width adjusting motor 24d is placed at a position where the sheet is easily received. It is moved by rolling (S105).

  As a result, the CPU 150 reduces the interval between the width adjusting members 24a and 24b to the position (S106) of the sheet width + about 10 mm from the sheet width obtained from the previously received sheet information, and stops the width adjusting motor 24d. (S107).

  Next, the CPU 150 rotates the sheet positioning motor 61 in the forward direction (S108), and moves the sheet positioning member 23 downstream from the staple point 19a of the stapler unit 18 to a position half the sheet length (S109). Then, the sheet positioning motor 61 is turned off (S110).

  The sheet carried from the apparatus main body 10 of the copying machine 1 through the flapper 3 is conveyed downstream by the conveyance roller 13 and turns on the conveyance path sensor 83 (S111). The CPU 150 waits for the trailing edge of the sheet to pass (OFF) the conveyance path sensor 83 (S112). When the conveyance path sensor 83 is turned off, the CPU 150 moves the width-adjusting members 24a and 24b to perform sheet width alignment (S113). The CPU 150 causes the width adjusting members 24a and 24b to perform the sheet width alignment operation each time the sheet is fed, and ends the width alignment operation when the final sheet is reached (S114).

  The CPU 150 turns on the front stapler motor 210 out of the two stapler motors 210 and 213 (S115) and indicates that the front stapler motor 18A has started to start. This is confirmed by turning off the P sensor 211 (S116). The front stapler 18A binds the sheet bundle. The CPU 150 measures the staple current value Ia of the front stapler motor 210 by the front current detection mechanism 251 and stores the result in the RAM 153 (S117).

  Here, the staple current value Ia is equal to the stapler motor H. After the P sensor 211 is turned off, it may be the value of one sampling after a predetermined time, or the largest value among a plurality of samplings. Or you may memorize | store as a determination flag whether the threshold value was exceeded predetermined times in having sampled in multiple times.

  Next, the CPU 150 determines whether or not the stapling operation has been completed. Detected by the P sensor 211 (S118). The CPU 150 is connected to the stapler motor H. When the P sensor 211 is turned on, it is determined that the stapling operation has been completed, and the front stapler motor 210 is turned off (S119).

  The back stapler motor 213 performs the same operation (S120 to S124).

  When the two staple current values Ia and Ib measured in the processes S117 and S122 are both larger than the preset threshold value I (S125), the CPU 150 shifts to a post-process continuation interruption operation after the process S200. In other cases, the CPU 150 shifts to a post-processing continuation operation after step S126.

  Here, the post-processing is interrupted when both of the staple current values Ia and Ib are larger than the threshold value I, but the post-processing is interrupted when either one of the staple current values is larger than the threshold value. Good.

  Further, when the determination flags stored at the time of measuring each staple current (S117, S122) indicate that both determination flags exceed the threshold value a predetermined number of times or more, the post-processing is interrupted. Alternatively, the post-processing may be interrupted when one of the determination flags indicates that the threshold value is exceeded a predetermined number of times or more.

  Further, either one of the staple current values or the determination flag may be used.

  The CPU 150 reverses the sheet positioning motor 61 and lowers the sheet positioning member 23 to a predetermined position so that the sheet folding position (generally, the binding position) can be moved to the folding point 60a (S126 to S128). , Wait at that position. Until the sheet positioning member 23 is moved up and down to a predetermined position, the bound sheet bundle is sandwiched between the transport roller 13 and the transport roller 14, sandwiched between the half-moon roller 17a and the elastic member 17d, and further the half-moon roller. 22a and the elastic member 22d are held in the conveyance path 301. However, depending on the length of the sheet bundle, it is not always sandwiched between them. For this reason, the sheet positioning member 23 is separated from the lower end of the sheet bundle.

  Since the sheet positioning member 23 is separated from the lower end of the sheet bundle, the CPU 150 drives the conveyance motor 51 again to rotate the conveyance roller 13 and the half-moon rollers 17a and 22a, thereby causing the sheet bundle to move to the sheet positioning member 23. It is lowered until it is received (S129). When the sheet bundle descends and the lower end is received by the sheet positioning member 23 and is detected by the sheet leading edge detection sensor 33 (S130), the CPU 150 turns off the conveyance motor 51 (S131).

  Next, the sheet folding device 60 turns on the ejection plate clutch 74a and the folding motor 64 (S132, S133). When the ejecting plate clutch 74a is turned on, the ejecting plate 25a starts to eject and pushes the sheet bundle into the nip pair of folding rollers 26 and 27. The CPU 150 continues to turn on the folding clutch until the protruding plate home position sensor 82 detects that the protruding plate 25a has reciprocated once (S134).

  Then, when the protruding plate home position sensor 82 detects that the protruding plate 25a has reciprocated once in the process S134, the CPU 150 turns off the protruding plate clutch 74a (S135). When the paper discharge sensor 29 detects the trailing end of the sheet bundle (S136), the CPU 150 turns off the folding motor 64 (S137). As a result, the sheet bundle is bound by the stapler unit 18, then folded in two by the folding device 60, becomes a booklet, and is discharged to the discharge tray 32.

  In processing S125 of the above processing, when the CPU 150 determines that the staple current values Ia and Ib are larger than the threshold values and the sheet bundle folding operation cannot be performed, the CPU 150 turns off the conveyance motor 51 (S200). For this reason, the bound sheet bundle is sandwiched between the transport roller 13 and the transport roller 14, sandwiched between the half-moon roller 17a and the elastic member 17d, and sandwiched between the half-moon roller 22a and the elastic member 22d. Stays on.

  Then, the CPU 150 transmits a processing interruption notification to the apparatus main body 10 of the copying machine 1 in order to prompt the user to take out the sheet bundle from which the bookbinding processing has been interrupted from the conveyance path 301 (S211). The apparatus main body 10 of the copying machine 1 opens the opening / closing door 303 to the user, for example, on the display unit 40 that is a notification means of the apparatus main body 10 based on the processing interruption notification received in step S211, and the inside of the conveyance path 301. To remove the sheet bundle from the sheet.

It is sectional drawing along the sheet conveyance direction of the sheet processing apparatus in embodiment of this invention. FIG. 2 is a front view of a stapler unit in the sheet processing apparatus of FIG. 1. FIG. 2 is a front view of a sheet folding device in the sheet processing apparatus of FIG. 1. FIG. 2 is a control block diagram of the sheet processing apparatus of FIG. 1. The staple current value of the front stapler motor in the sheet processing apparatus of FIG. It is a graph which shows the relationship with the detection operation of P sensor. FIG. 3 is a cross-sectional view of the image forming apparatus along the sheet conveyance direction in the embodiment of the present invention. 3 is a flowchart for explaining the operation of the sheet processing apparatus shown in FIG. 1. It is the flowchart which succeeded the flowchart of FIG. It is the flowchart which succeeded the flowchart of FIG. It is the flowchart which succeeded the flowchart of FIG. It is the flowchart which succeeded the flowchart of FIG.

Explanation of symbols

1 Copying machine (image forming device)
2 Sheet processing apparatus 10 Apparatus body of copying machine (image forming apparatus) 18 Stapler units 18A, 18B Stapler (first processing means, binding means)
40 Display section (notification means)
60 Sheet folding device (second processing means, folding means)
150 CPU (stopping means)
251 Current detection mechanism (load detection means)
252 Back current detection mechanism (load detection means)
902 Image forming unit

Claims (4)

In a sheet processing apparatus that performs a first processing operation on a sheet bundle by a first processing unit and then performs a second processing operation on the sheet bundle by a second processing unit.
Load detecting means for detecting a load during the first processing operation of the first processing means;
Stop means for stopping the second processing operation of the second processing means when the load detected by the load detection means is a predetermined value or more,
A sheet processing apparatus. Informing means for informing that the first processing means has stopped the first processing operation,
The sheet processing apparatus according to claim 1. The first processing means is a binding means for binding the sheet bundle, and the first processing operation is a needle binding operation for binding the sheet bundle;
The second processing means is a bending means for bending the sheet bundle, and the second processing operation is a bending action for bending the sheet bundle;
The sheet processing apparatus according to claim 1, wherein the sheet processing apparatus is a sheet processing apparatus. An image forming unit for forming an image on a sheet;
A sheet processing apparatus that processes a sheet on which an image is formed by the image forming unit,
The sheet processing apparatus is the sheet processing apparatus according to any one of claims 1 to 3.
An image forming apparatus.

Images