JP6865070B2 - Sheet processing device and image forming system equipped with it - Google Patents

Description

The present invention relates to a sheet processing device that performs a processing such as binding on an image-formed sheet that is sequentially conveyed from the image forming device side and discharges the sheet, and particularly to static electricity that charges the sheet bundle after the processing. ..

In image forming devices such as copiers, printers, facsimiles, and digital multifunction devices, the image-formed sheets are sequentially carried out to the subsequent processing device, and in the processing device, the brought-in sheets are discharged as they are and the paper ejection tray is used. There is known a type in which the sheet is loaded on the top, or the sheet bundle is bound, and then the sheet is folded and discharged onto the accumulation tray for loading.

In a processing apparatus that performs such a sheet folding process, the image-formed sheets are accumulated as a sheet bundle, and staples are stapled at one or a plurality of places near the center line orthogonal to the transport direction of the accumulated sheet bundle (hereinafter referred to as the present application). Then, there is a sheet processing device that performs a process of folding a stapled sheet bundle in half along the center line (hereinafter referred to as "middle folding" in the present application). (See, for example, Japanese Patent Application Laid-Open No. 2004-10197)

Each sheet of the sheet bundle to be subjected to such a center-folding process is originally formed with an image using static electricity, and even if the static electricity charged in the sheet bundle is eliminated in the image forming apparatus, the above-mentioned sheet is used. In the processing device, the surface of the sheet bundle may be charged again due to the friction between the sheet transport path and the sheet, or the friction between the rollers and the sheet caused by pressing the sheet bundle with a pair of rollers to perform the folding process. is there.

In recent years, electronic devices have come to be widely used in homes and factories, and there is a problem that electromagnetic waves generated from electronic devices adversely affect the operation of other electronic devices. For this reason, various countries around the world have set various electromagnetic wave regulations (for example, IEC and CISPR) regarding such electromagnetic interference (EMI). Since the sheet processing device is also an electronic device, it is necessary to strictly comply with the standards set by these regulations.

In addition to being compliant with electromagnetic wave regulations, in a sheet processing device, the electric charge charged on the sheet surface causes various troubles such as sheet jam because the sheet bundles are adsorbed to each other, and the sheet bundle is folded in the middle. The sheet bundles are usually loaded on the stacking tray, but the sheet bundles are attracted to each other, which adversely affects the alignment of the sheet bundles at the time of loading.

Therefore, even in the conventional sheet processing apparatus, in order to remove the electric charge on the sheet surface, the static elimination means (static elimination brush, etc.) for removing the electric charge by contacting the sheet surface between the folding processing unit and the tray on which the sheet bundle is loaded. ) Was known to be placed. (For example, refer to Japanese Patent No. 4193818, Japanese Patent Application Laid-Open No. 11-171388, Japanese Patent Application Laid-Open No. 9-63786, and Japanese Patent Application Laid-Open No. 9-58915).

Japanese Unexamined Patent Publication No. 2004-10197 Japanese Patent No. 4193818 Japanese Unexamined Patent Publication No. 11-171388 Japanese Unexamined Patent Publication No. 9-63786 Japanese Unexamined Patent Publication No. 9-58915

When static electricity is removed using an electrostatic static eliminator brush or the like charged on the sheet surface, the discharge current is reduced because the static eliminator brushes or the like evenly arranged over a wide range in the direction orthogonal to the transport direction of the highly insulating sheet. No large electromagnetic waves are generated without being dispersed and concentrated at one point.

However, in a sheet processing device that staples a bundle of sheets and folds them in the middle, when the charged sheet comes into contact with a static eliminator brush that is usually made of metal and has high conductivity, the static electricity charged on the sheet passes through the static eliminator brush. As a result, a large discharge current flows, so it is observed as a large interfering electromagnetic wave. In the previous EMC regulation, it was excluded from the standard of instantaneous radiation emission over 1 GHz. However, due to the recent revision of the standard for electromagnetic wave interference, the regulation for instantaneous interference waves has become stricter, and the regulation will extend to the peak detection (peak detection) of radiation emissions above 1 GHz, which was previously excluded. became.

In particular, the stapler needles made of highly conductive metal allow a relatively large current to flow instantly through the elongated path, so that when they come into contact with the static elimination brush, they will be charged against the electric charge distributed on the sheet surface around the stapler needles. It becomes a conductive path and instantly releases a discharge energy larger than the discharge energy due to the contact between the static elimination brush and the sheet. This makes it difficult to keep the electromagnetic waves generated by the discharge energy generated by the contact between the stapler needle and the static elimination brush within the stricter standards for the revised EMC.

The present invention has been made in view of the above problems, and in a sheet processing apparatus that performs a center folding process of a sheet bundle, when the charged sheet comes into contact with the static elimination brush, the charged sheet passes through the stapler of the stapler. The purpose is to effectively prevent the discharge current from flowing through the static elimination brush.

Therefore, as the first aspect of the present invention, the transport means for transporting the carried-in sheets in a predetermined transport direction, the stack portion for accumulating the sheets transported by the transport means, and the stack portion. A saddle stitching means for performing a binding process using a binding member having conductivity at one or a plurality of predetermined positions of the stacked sheet bundles, a folding means for performing a folding process on the bound sheet bundle, and the folding means. At a static electricity elimination position where the discharge means for discharging the sheet bundle folded in the above direction and the discharge direction of the sheet bundle discharged by the discharge means intersect with the discharge direction of the folded sheet bundle and come into contact with the folded sheet bundle, the sheet is placed on the sheet. A static eliminating member for removing static electricity to be charged is provided, and the static eliminating member is provided with a sheet so as not to come into contact with the binding member when the sheet bundle is discharged and the binding member applied to the sheet bundle passes through. It is characterized by moving to a retracted position away from the bundle.

Here, the static eliminator member is electrically connected to a ground connection member for ensuring a ground state during movement between the static eliminator position and the retracted position, and is linked to the static eliminator position in conjunction with the operation of the folding means. It is characterized in that it is configured to be movable between the retracted positions.

Further, a sensor for detecting the position of the folded sheet bundle is arranged between the folding means and the static elimination member, and the movement of the static elimination member from the static elimination position to the retracted position is performed by the sensor. Based on the detection, the binding member applied to the sheet bundle is performed at a timing before the static elimination member comes into contact with the static elimination member, and the movement of the static elimination member from the retracted position to the static elimination position is based on the detection of the sensor. The binding member applied to the sheet bundle may be performed at a timing after passing through the static elimination member.

As a second aspect of the present invention, a transport means for transporting the carried-in sheets in a predetermined transport direction, a stack portion for accumulating the sheets transported by the transport means, and a sheet bundle accumulated in the stack portion. A saddle stitching means that performs a binding process using a binding member having conductivity at one or a plurality of predetermined positions, a folding means that folds the bound sheet bundle, and the folded sheet bundle. A static electricity eliminating member which is arranged in a direction intersecting the discharging direction and which eliminates static electricity charged in the folded sheet bundle is provided, and the static electricity removing member is applied to the sheet bundle when the sheet bundle is discharged. It is characterized in that the binding member is shielded by an insulating shielding member so as not to come into contact with the binding member when passing through.

Here, the shielding member is configured to be movable between a non-shielding position that enables the static electricity eliminating member to eliminate static electricity and a shielding position that shields the static electricity elimination in conjunction with the operation of the folding means. It is characterized by that.

Further, a sensor for detecting the position of the folded sheet bundle is arranged between the folding means and the static elimination member, and the movement of the shielding member from the non-shielding position to the shielding position is performed by the sensor. The binding member applied to the sheet bundle is performed at a timing before the static elimination member comes into contact with the static elimination member, and the movement of the shielding member from the shielding position to the non-shielding position is detected by the sensor. The binding member applied to the sheet bundle may be performed at a timing after passing through the static elimination member.

According to the present invention, according to the first or second aspect, the static electricity eliminating member for eliminating static electricity charged in the folded sheet bundle and the conductive binding member such as metal are mutually connected when the sheet bundle is discharged. Since it is possible to prevent the sheet bundle from being discharged from the static electricity charged in the sheet bundle via the static eliminator member, it is possible to effectively prevent the generation of radiation emissions exceeding 1 GHz, for example, exceeding the regulation value of the sheet. A good alignment of paper discharge on the stack loading tray was achieved.

An explanatory diagram of the overall configuration of the image forming apparatus is shown. An explanatory diagram of the configuration of the sheet processing apparatus is shown. The schematic view from the side of the main part of the sheet processing apparatus which concerns on this invention is shown. The arrangement configuration of the static elimination member is shown in the front view. The schematic view from the side of the mechanism which moves a static elimination member between a retracting position and a static elimination position by a solenoid is shown. A modified example of the arrangement configuration of the static elimination member is shown in the front view. The schematic view from the side of the mechanism which moves a static elimination member between a retracting position and a static elimination position by a cam is shown. An explanatory view from the side surface of the drive mechanism for rotating the static eliminator member to move between the retracted position and the static eliminator position is shown. An explanatory diagram from the side of a configuration for switching between an insulated state and a non-insulated state by fixing the static eliminator member and allowing the blocking member to appear and disappear between the sheet bundle and the sheet bundle is shown. The flowchart explaining the center folding processing operation of a sheet bundle in a sheet processing apparatus is shown.

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

First, an image forming apparatus to which the sheet processing apparatus according to the present invention is effectively applied will be described.

As shown in FIG. 1, the image forming apparatus 100 includes an image forming apparatus main body A and a sheet processing apparatus B installed adjacent to the image forming apparatus main body A. The image forming apparatus main body A is composed of an image forming unit A1, a scanner unit A2, and a feeder unit A3. The device housing 1 contains a paper feeding unit 2, an image forming unit 3, a paper ejection unit 4, and a data processing unit 5.

The paper feed unit 2 is composed of cassette mechanisms 2a, 2b, 2c for accommodating a plurality of sizes of sheets for forming an image, respectively, and feeds a sheet of a size specified by a main body control unit (not shown) to the paper feed path 6. The cassette mechanisms 2a, 2b, and 2c are detachably installed from the paper feeding unit 2, and each cassette mechanism has a built-in separation mechanism for separating the internal sheets one by one and a paper feeding mechanism for feeding out the sheets. The paper feed path 6 is provided with a transport roller that feeds the sheets supplied from the cassette mechanisms 2a, 2b, and 2c to the downstream side, and a resist roller pair that aligns the tips of the sheets at the end of the path. There is.

Further, a large-capacity cassette 2d and a manual feed tray 2e are connected to the paper feed path 6, the large-capacity cassette 2d is composed of an optional unit for storing a sheet having a size to be consumed in large quantities, and the manual feed tray 2e is composed of an optional unit. It is configured to be able to supply special sheets such as cardboard sheets, coating sheets, and film sheets that are difficult to feed separately.

The image forming unit 3 is composed of, for example, an electrostatic printing mechanism, includes a rotating photosensitive drum 9, a light emitter 10 that emits an optical beam around the photosensitive drum 9, a developer 11, and a cleaner (not shown). It is a configuration in which and is arranged. The illustrated one shows a monochrome printing mechanism, in which a latent image is optically formed on the photosensitive drum 9 by a light emitter 10, and toner ink is adhered to the latent image by a developing device 11.

Then, the sheet is sent from the paper feed path 6 to the image forming unit 3 at the timing of forming an image on the photosensitive drum 9, the image is transferred onto the sheet by the transfer charger 12, and the fixing roller 13 arranged in the paper ejection path 14 is arranged. Settle in. A paper ejection roller 15 and a paper ejection port 16 are arranged in the paper ejection path 14, and the sheets are conveyed to the sheet processing device B described later.

The scanner unit A2 uses the platen 17 on which the image document is placed, the carriage 18 that reciprocates along the platen 17, the photoelectric conversion means 19, and the photoelectric conversion means 19 that converts the light reflected from the document on the platen 17 by the carriage 18. It is provided with a reduction optical system 20 that guides the carriage. Further, the scanner unit A2 is provided with the traveling platen 21, and the sheet sent from the feeder unit A3 is read by the carriage 18 and the reduction optical system 20. The photoelectric conversion means 19 converts the optical output from the reduction optical system 20 into image data by photoelectric conversion, and outputs an electric signal to the image forming unit 3.

The feeder unit A3 is composed of a paper feed tray 22, a paper feed path 23 for guiding the sheet fed from the paper feed tray 22 to the traveling platen 21, and a paper output tray 24 for storing a document whose image has been read by the platen. There is.

FIG. 2 shows a configuration of a sheet processing device B that processes a sheet on which an image sent from the image forming device main body A is formed. In the sheet processing device B, the device housing 27 is arranged at substantially the same height as the housing 1 of the image forming apparatus main body A, and the carry-in entrance 26 is communicated with the paper ejection port 16 of the image forming apparatus main body A.

The sheet processing device B has a sheet carry-in path 28 into which a sheet is introduced from the carry-in inlet 26, and a first paper discharge path 31, a second paper discharge pass 32, and a third paper discharge that are branched and formed downstream of the sheet carry-in route 28. A paper pass 30, a first path switching means 33, and a second path switching means 34 are provided. The first path switching means 33 includes a flapper guide for changing the sheet transport direction, a mode in which the sheet from the carry-in port 26 is guided to the third paper discharge path 30 by a drive means (not shown), and a first paper discharge. The mode is switched to the mode of guiding in the direction of the pass 31 or the second paper ejection pass 32.

The first paper ejection pass 31 and the second paper ejection pass 32 can be switched back to the second paper ejection pass 32 by reversing the transport direction of the sheet once introduced in the first paper ejection pass 31. They are arranged in communication with each other. The second path switching means 34 is introduced into a mode in which the sheet sent from the first path switching means 33 is introduced into the first paper ejection path 31 and a mode in which the sheet is introduced into the first paper ejection path 31 by a driving means (not shown). It is switched to the switchback transport mode in which the sheet is introduced into the second paper ejection path 32. A punch unit 50 for punching a punch hole in the carried-in sheet is arranged in the sheet carry-in route 28.

Then, the sheet processing device B aligns and loads the sheets sent from the first paper ejection pass 31 and binds the sheets, and the sheets sent from the second paper ejection pass 32 are sheeted. It is provided with a second processing unit B2 for binding by forming a bundle and folding the sheet bundle in the middle, and a third processing unit B3 for offsetting the sheets sent from the third paper ejection path 32 by a predetermined amount in the orthogonal direction. ing. The device housing 27 is provided with a first tray 49, a second tray 61, and a third tray 71 for loading sheets or sheet bundles that are processed and sent by the processing units B1, B2, and B3, respectively. ..

The first processing unit B1 includes a processing tray 37 for aligning and loading the sheets sent from the paper ejection port 35, and a stapler unit 38 for binding the loaded sheet bundles. The processing tray 37 is provided below the paper ejection port 35 of the first paper ejection path 31 to switch back the transport direction of the sheet carried out from the paper ejection port 35, and the sheet is introduced onto the processing tray 37. To. Then, the sheet is positioned at a predetermined binding position on the processing tray 37 by the positioning mechanism and stapled by the stapler unit 38, and the bound sheet bundle is carried out to the first tray 49 by the sheet bundle unloading mechanism.

The third processing unit B3 sorts the sheets conveyed to the third paper ejection pass 30 by offsetting them in the direction orthogonal to the paper ejection, and stores them in the third tray 71.

The second processing unit B2 performs a center folding process of the sheet bundle 51, which is closely related to the present invention, and loads the sheets sequentially sent from the first paper ejection path 31 by switchback transport. After binding the central portion, the central portion is folded in the middle and introduced into the second tray 61.

The second processing unit B2 is positioned with a guide member 66, which is a stacking unit for loading the sheets in a bundle, and a regulation stopper 67 for positioning by restricting the tip of the sheet at a predetermined position on the guide member 66. A saddle stitch staple unit 63 that binds the central portion of the sheet bundle 51 that has been bound, a folding roll pair 64 that folds the sheet bundle 51 at the central portion after the binding process, a folding blade 65, and the folded sheet bundle 51. It is composed of a pair of discharge rollers 69 that nip and send out to the second tray 61.

As disclosed in JP-A-2008-184324, JP-A-2009-051644, etc., the saddle-stitched staple unit 63 has a sheet central portion (a sheet bundle sandwiched between the head unit 63a and the anvil unit 63b). The position is moved along the line) and the stitching process is performed.

Further, in the folding process, the folding blade 65 is inserted into the nip portion of the folding roll pair 64 which is pressed against each other through the crease of the sheet bundle, and the inserted sheet bundle is folded by the rotation of the folding roll pair 64. The pair of rollers constituting the folding roll pair 64 are each made of a material having a relatively large coefficient of friction, such as a rubber roller. For example, by using a soft material such as rubber, it is possible to accurately transfer the sheet bundle in the rotational direction while bending it. It is even better to lining a soft material such as rubber.

FIG. 3 schematically shows a main part of the folding processing portion of the second processing portion B2 in a side view, and the folding roller pair 64 and the folding blade 65 are provided so as to sandwich the guide member 66 and face each other. The folding blade 65 is arranged so that its longitudinal direction is orthogonal to the conveying direction of the sheet guided to the guide member 66, and the folding roller pair 64 nips penetrate the hole 57 formed in the side wall of the guide member 66. It is configured to move linearly toward the part.

Therefore, when the folding blade 65 advances toward the nip portion of the folding roller pair 64 while the sheet bundle 51 is integrated on the guide member 66, the sheet bundle 51 is formed with the folding roller pair while the crease is formed by the folding blade 65. It is extruded toward 64, sandwiched by the rotation of the folding roller vs. 64, and folded. Although not shown, the rotational movement of the folding roller pair 64 and the reciprocating motion of the folding blade 65 are simultaneously driven by the same motor.

The discharge roller pair 69 is arranged on the downstream side of the rear stage of the folding roller pair 64, and sends the sheet bundle 51 folded by rotation to the discharge port 62. The discharge roller pair 69 is driven by a motor different from the motor that drives the folding roller pair 64 and the folding blade 65.

The folding roll pair 64 to be folded has an elongated shape so as to be in contact with the sheet bundle 51 in the overall length in the width direction orthogonal to the transport direction thereof in order to form a uniform crease in the sheet bundle 51. It is composed of a material with a large coefficient of friction. Therefore, since the sheet bundle 51 comes into contact with the folding roll pair 64 on the entire surface thereof, strong friction is generated and strong static electricity is generated. Therefore, as shown in FIG. 4, a static eliminator member 52 for removing static electricity charged in the folded sheet bundle 51 is supported by the mounting stay 55 at the discharge port 62 along the width direction of the sheet bundle 51. They are arranged continuously. The static elimination member 52 includes a static elimination brush 52a that comes into contact with the surface of the sheet bundle 51 to eliminate static electricity.

On the other hand, the sheet bundle 51 has a portion bound by a metal staple 45. FIG. 4 shows the movement path P1 of the staple needle 45 (shown in FIG. 5) bound at two central locations by the saddle stitch staple unit 63 when the sheet bundle 51 is discharged by the discharge roller pair 69, and the end at one location. The movement path P2 of the bound portion is shown, and a large discharge current flows through the portions of the static elimination brush 52a located in the paths P1 and P2 via the staple needle 45. In order to prevent this, the static elimination member 52 moves between a static elimination position where static elimination is performed by contacting the surface of the sheet bundle 51 and a distant retracting position which does not contact the sheet bundle 51, and the static elimination brush 52a is moved at the retracting position. Is configured to avoid contact with the staple 45.

FIG. 5 shows an embodiment in which the static elimination member 52 is lifted upward by the solenoid 40 to avoid the static elimination member 52 in the retracted position. The solenoid 40 is connected to one end of a lever 41 whose plunger is rotatably supported at the center, and an operating culm 42 is connected to the other end of the lever 41. Then, the operating culm 42 is provided with a holding portion 58 on the operating side, and the static elimination member 52 is fastened to the holding portion 58 by the screw 56. At this time, the screw 56 is fastened through a long hole (not shown) formed in the mounting surface of the mounting stay 55 which is fixedly provided.

The static eliminator member 52 is usually in a static eliminator position in which the static eliminator brush 52a comes into contact with the surface of the sheet bundle 51 discharged to the discharge port 62 and is lowered so as to eliminate static electricity charged. Then, when the solenoid 40 sucks and the lever 41 rotates clockwise around the shaft 41a in the figure, the holding portion 58 is lifted. At this time, the shaft of the screw 56 slides in the elongated hole and moves upward, so that the static elimination member 52 is pulled up to a retracted position where the static elimination brush 52a does not come into contact with the sheet bundle 51. By electrically connecting the mounting stay 55 to the ground connection member, the static eliminator member 52 slides through the elongated hole to ensure the ground state even while the static eliminator position and the retracted position are moving.

As will be clarified later, the sheet bundle 51 is discharged from the discharge roller pair 69 to the discharge port 62 with the crease portion bound by the staple needle 45 at the head. Therefore, when the sensor 59 arranged at the discharge port 62 detects the tip end portion of the folded sheet bundle 51, the solenoid 40 is suction-operated to avoid contact between the staple needle 45 and the static elimination brush 52a. As a result, the metal staple 45 of the sheet bundle 51 and the static elimination brush 52a are not in contact with each other, so that the discharge current is prevented from flowing to the static elimination brush 52a via the staple 45. Alternatively, since the fold portion bound by the staple 45 is located at the head of the sheet bundle 51 in the discharge direction in the direction of discharge from the discharge roller pair 69 to the discharge port 62, the folding roller pair 64 or the folding blade The seat bundle 51 may be moved to the retracted position at the same time as the drive of 65 is started, or during a predetermined time before the head of the sheet bundle 51 reaches the position where the static elimination brush 52a is arranged.

In the example shown in FIG. 4, the static elimination brush 52a is continuously formed along the width direction of the sheet bundle 51, but as shown in FIG. 6, the portions located in the transport paths P1 and P2 of the static elimination brush 52a are formed. The divided brush portion 52a'may be formed, and only the divided brush portion 52a' may be moved up and down to avoid contact with the staple needle 45.

FIG. 7 schematically shows an example in which the static elimination member 52 is moved up and down by the rotation of the rotary cam 35 interlocked with the motor for driving the folding roller pair 64 and the folding blade 65. The static elimination member 52 is connected to the drive member 36, and the drive member 36 reciprocates up and down while the rotary cam 35 makes one clockwise rotation in the figure. That is, the drive member 36 rises when it comes into contact with the convex portion 35a due to the rotation of the rotary cam 35, and then descends when it comes into contact with the concave portion 35b from the convex portion 35a. Therefore, the static elimination member 52 moves to the retracted position above the discharge port 62 when the driving member 36 rises, and moves to the static elimination position when descending.

According to such a configuration, the center folding operation of the sheet bundle 51 by the roller pair 64 and the folding blade 65 and the retracting operation of the static elimination brush 52a to the discharge port 62 are intentionally performed by the same driving force of the motor. Even if a sensor for detecting the sheet bundle 51 is not provided, it is possible to control the static elimination member 52 to be pulled up at the timing when the staple needle 45 approaches the static elimination brush 52a by using a timing cam or the like.

FIG. 8 shows another embodiment in which contact between the sheet bundle 51, the staple needle 45, and the static elimination brush 52a is avoided. In this example, the upper end of the static elimination member 52 is rotatably connected to the lower end of the mounting stay 55 by a shaft 46, and the shaft 46 meshes with the reduction gear mechanism 43 via a gear (not shown) to be the output shaft of the forward / reverse motor 48. Is connected to. With this configuration, when the sensor 59 detects the tip of the sheet bundle 51, the motor 48 is rotated, so that the static elimination member 52 rotates around the shaft 46 as a fulcrum and moves to the upper retracted position. Contact between the staple 45 and the static elimination brush 52a is avoided.

In all of the above embodiments, the static eliminator brush 52a is moved or rotated upward to avoid the retracted position, but the static eliminator brush 52a is fixed in position and the static eliminator brush 52a comes into contact with the staple 45. At that time, there is also a method of preventing the discharge current from flowing to the static eliminator brush 52a via the staple 45 by insulating the static eliminator brush 52a and the sheet bundle 51.

FIG. 9 schematically shows an embodiment in which the static eliminator member 52 is fixedly arranged and the blocking member 46 is advanced between the static eliminator brush 52a and the sheet bundle 51 to insulate the two. The blocking member 46 is connected to a drive member 44 that can move up and down, and the drive member 44 reciprocates up and down due to the rotation of the rotary cam 47, so that the blocking member 46 advances between the static elimination brush 52a and the sheet bundle 51. It is configured to insulate and then exit and return to the standby position. Similar to the example of FIG. 6, the rotary cam 47 has a configuration in which the rotary cam 47 is rotated once by the motor for driving the folding roller pair 64 and the folding blade 65, and the drive member 44 has the rotary cam 47 clockwise in the same figure. In a state where it abuts toward the convex portion 47a in one rotation, it descends, advances the blocking member 46 between the static elimination brush 52a and the sheet bundle 51, and abuts from the convex portion 47a toward the concave portion 47b. In the state of being lifted, the sealing member 46 is raised to retract from between the static elimination brush 52a and the sheet bundle 51.

The operation of the second processing unit B2 in the sheet processing device B having the above configuration will be described with reference to the flowchart shown in FIG. First, the sheet processing device B introduces the sheet sent to the first paper ejection path 31 into the second paper ejection path 32 by switchback transfer, and positions the regulation stopper 67 in advance according to the size of the sheet. It leads to the guide member 66 (step S1).

Then, when the sheet reaches the guide member 66 (step S2), the sheet is accumulated on the regulation stopper 67 (step S3). Then, it is determined whether or not the sent sheet is the final sheet (step S4). In this case, the sheet processing device B is instructed by the image forming apparatus main body A to indicate the number of sheets in one set of sheet bundles 51 to be folded in the middle, and a sheet detection sensor (FIG. By counting the sheet detection signal from (not shown), it is determined whether the sheet is the final sheet. If it is not the final sheet, the process returns to step S2.

When the sheet processing device B determines that it is the final sheet, it determines whether or not saddle stitching by staples is instructed by the image forming apparatus main body A (step S5). When the saddle stitching is instructed, the saddle stitching staple unit 63 is operated to perform the saddle stitching operation on the sheet bundle 51 integrated in the guide member 66 (step S6). At this time, the position of the regulation stopper 67 is adjusted in advance so that the sheet bundle 51 faces the saddle stitch staple unit 63 so that the staple needle binds in the width direction of the sheet in the center of the sheet in the transport direction. Staple binding is applied to the center of the bundle 51.

When the binding operation is completed, the sheet processing device B adjusts the position of the regulation stopper 67 downward so that the center of the bound sheet bundle 51 faces the nip portion of the folding roll pair 64, and then the folding roller pair. By driving the motor that drives the 64 and the folding blade 65, the folding roll pair 64 is rotated and the folding blade 65 is moved to the nip portion at the same time, and the folding operation is performed at the binding processing position on the sheet bundle 51. (Step S7). If the image forming apparatus main body A does not instruct saddle stitching by staples, the process is directly from step S5 to step S7, and the sheet bundle 51 is not bound and only folded at the center. It is said.

After that, at the end of the center-folding operation, the blade 65 moves to the standby position, and the center-folded sheet bundle 51 is conveyed to the discharge roller pair 69 with the binding portion by the staple needle 45 at the head. At this time, the discharge roller pair 69 is rotating, and the delivered sheet bundle 51 is discharged to the discharge port 62 (step S8). Then, the sheet processing device B moves the static elimination member 52 to the retracted position by raising it (example shown in FIGS. 5 and 7) or rotating it (example shown in FIG. 8), or moves the static elimination brush 52a and the sheet bundle 51 to the retracted position. A blocking member 46 is interposed between them (example shown in FIG. 9) (step S9). Therefore, when the binding portion at the beginning of the sheet bundle 51 is discharged from the discharge port 62, the static elimination action of the sheet bundle 51 by the static elimination brush 52a is released.

The sheet processing device B returns the static elimination member 52 to the static elimination position at the timing when the staple needle 45 passes, or causes the sealing member 46 to exit from between the static elimination brush 52a and the sheet bundle 51. , The static elimination action of the sheet bundle 51 by the static elimination brush 52a is restored (step S10). Therefore, thereafter, the sheet bundle 51 is discharged while being statically eliminated by passing through the discharge port 62 (step S11). Then, the sheet processing device B continues the rotation of the discharge roller pair 69 for a certain period of time even after stopping the drive of the motor that drives the folding roller pair 64 and the folding blade 65, and conveys the sheet bundle 51 to the tray 61. And end the operation (step S12).

In the sheet processing device B described in detail above, the static electricity removing brush 52a for removing static electricity charged on the folded sheet bundle and the conductive staple needle 45 made of metal or the like after the binding treatment are formed on the sheet bundle. The static eliminator brush 52a is temporarily retracted so as not to come into contact with each other when the 51 is discharged. As a result, it is possible to prevent the generation of noise caused by an excessive current flowing into the static elimination brush due to contact with the staple needle. In addition, by suppressing the amount of charge in the sheet bundle, it is possible to prevent disturbance due to static electricity when the sheet bundle after the middle folding process is accumulated in the tray.

B Sheet processing device 32 Transport path (transport means)
46 Blocking member 52 Static elimination member 52a Static elimination brush 59 Sensor 66 Guide member (stack part)
63 Saddle stitch staple unit (saddle stitching means)
64 Folding roller pair (folding means)
100 image forming device

Claims (8)

A transport means for transporting the carried-in sheet in a predetermined transport direction, and
A stack portion for accumulating sheets transported by the transport means, and a stack portion.
A saddle stitching means for performing a binding process using a binding member having conductivity at a predetermined position of one or a plurality of sheet bundles accumulated in the stack portion.
A folding means for folding the bound sheet bundle,
A static eliminating member that is arranged in a direction intersecting the discharge direction of the folded sheet bundle and that eliminates static electricity charged on the sheet at a static eliminating position that contacts the folded sheet bundle is provided.
The static elimination member is a sheet processing device that moves to a retracted position away from the sheet bundle so as not to come into contact with the binding member when the sheet bundle is discharged and the binding member applied to the sheet bundle passes through. The sheet processing apparatus according to claim 1, wherein the static eliminator member is electrically connected to a ground connection member for ensuring a ground state during movement between the static eliminator position and the retracted position. The sheet processing apparatus according to claim 1 or 2, wherein the static elimination member is configured to be movable between the static elimination position and the retracted position in conjunction with the operation of the folding means. A sensor for detecting the position of the folded sheet bundle is arranged between the folding means and the static elimination member.
The movement of the static eliminator member from the static eliminator position to the retracted position is performed at a timing before the binding member applied to the sheet bundle comes into contact with the static eliminator member based on the detection of the sensor.
The movement of the static elimination member from the retracted position to the static elimination position is performed at a timing after the binding member applied to the sheet bundle passes through the static elimination member based on the detection of the sensor.
The sheet processing apparatus according to claim 1 or 2. A transport means for transporting the carried-in sheet in a predetermined transport direction, and
A stack portion for accumulating sheets transported by the transport means, and a stack portion.
A saddle stitching means for performing a binding process using a binding member having conductivity at a predetermined position of one or a plurality of sheet bundles accumulated in the stack portion.
A folding means for folding the bound sheet bundle,
A static eliminator member that is arranged in a direction intersecting the discharge direction of the folded sheet bundle and that eliminates static electricity charged in the folded sheet bundle.
With
The static elimination member is a sheet processing device that is shielded by an insulating shielding member so that the sheet bundle is discharged and the binding member applied to the sheet bundle does not come into contact with the binding member. The shielding member is configured to be movable between a non-shielding position that enables the static electricity eliminating member to eliminate static electricity and a shielding position that shields the static electricity elimination in conjunction with the operation of the folding means. The sheet processing apparatus according to claim 5. A sensor for detecting the position of the folded sheet bundle is arranged between the folding means and the static elimination member.
The movement of the shielding member from the non-shielding position to the shielding position is performed at a timing before the binding member applied to the sheet bundle comes into contact with the static elimination member based on the detection of the sensor.
The movement of the shielding member from the shielding position to the non-shielding position is performed at a timing after the binding member applied to the sheet bundle passes through the static elimination member based on the detection of the sensor.
The sheet processing apparatus according to claim 5. An image forming device that forms an image on a sheet,
The sheet processing apparatus according to any one of claims 1 to 7.
An image forming system equipped with.

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