Sheet cutting device and image forming apparatus

Abstract

To provide a sheet cutting device and an image forming device small in size and having no possibility of bending or deforming a cut sheet.SOLUTION: The cutter unit 10 includes the fixed blade 13 extending in the sheet-width direction, the movable blade 15 in sliding contact with the fixed blade 13, the carriage 16 movable in the sheet-width direction, and the left-side 40B1 provided at one end of the carriage 16 in the moving direction and configured to prevent the movement of the carriage 16, and the carriage 16 includes the abutment portion 40B1 provided on one end side of the carriage 16 in the moving direction and configured to abut on the left-side 162C, and the abutment portion inner wall is provided at least upstream of the movable blade 15 in the conveying direction of the sheet S. And a projecting part 161E projecting to the other end side in the moving direction of the carriage 16, and the left sidewall 40B1 is arranged so that the projecting part 162C of the carriage 16 overlaps with a part of a passing range through which the sheet S passes when the abutting part 40B1 of the carriage 16 abuts on the left sidewall 161E.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present application relates to a sheet cutting device that cuts a sheet and an image forming apparatus that includes the sheet cutting device. [Background technology]

[0002] Patent Document 1 describes an image forming apparatus that includes a cutter consisting of a moving blade and a fixed blade, and cuts a sheet by moving the moving blade along the fixed blade.

[0003] Specifically, the fixed blade is arranged in a direction perpendicular to the sheet conveying direction, the sheet is moved by the sheet conveying device along a sheet guide provided upstream of the fixed blade in the sheet conveying direction to the cutting position, and the movable blade cuts the sheet by moving the fixed blade in the sheet width direction along the sheet while the sheet is stopped by the cutter drive mechanism.

[0004] The range of movement of the movable blade is set to be sufficiently large relative to the width of the sheet to be cut, and the standby position of the movable blade where it starts moving for cutting and the stopping position where it stops once before returning to the standby position after cutting are both set so that the carriage holding the movable blade is outside the range through which the sheet passes. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2024-18327 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the image forming device described in Patent Document 1, the carriage of the moving blade is outside the range through which the sheet passes, so if the sheet is curled, the sheet upstream of the cutting position in the sheet transport direction may lift up from the sheet guide.In this case, the leading edge of the sheet may collide with the carriage holding the moving blade as it moves back to the standby position, causing problems such as the sheet being bent or deformed.

[0007] Furthermore, the range of movement of the carriage is set to be large relative to the width of the sheet being used, which has been a factor that hinders miniaturization, particularly in the width direction.

[0008] An object of the present application is to provide a compact sheet cutting device and an image forming apparatus in which cut sheets are not likely to bend or deform. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the sheet cutting device described in the embodiment comprises a fixed blade extending in the sheet width direction perpendicular to the sheet conveying direction, a carriage having a movable blade that slides against the fixed blade and that is movable in the sheet width direction, and a stopper that is provided at one end of the carriage in the moving direction and that prevents the carriage from moving, the carriage having a contact portion that is provided at one end of the carriage in the moving direction and that can abut against the stopper, and a protrusion that is provided at least upstream of the movable blade in the sheet conveying direction and that protrudes to the other end of the carriage in the moving direction, and the stopper is positioned so that when the contact portion of the carriage abuts against the stopper, the protrusion of the carriage overlaps with a portion of the passing range through which the sheet passes when conveyed. [Effects of the Invention]

[0010] According to the sheet cutting device described in the embodiment, the protrusion does not come off the sheet upstream of the cutting position even when the device is stopped after cutting, and serves as a guide when returning and when conveying the sheet, so there is no risk of the sheet colliding with the side of the sheet and deforming the sheet, and there is no risk of the sheet colliding with the carriage when conveying the sheet. Also, because part of the carriage stops at a position overlapping the sheet passing range, it is possible to keep the sheet width to the minimum necessary. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view of a multifunction peripheral according to a first embodiment. [Figure 2] FIG. 10 is a perspective view showing a state in which the cutter unit is attached by being sandwiched between the cutter attachment frame. [Figure 3] FIG. 2 is a perspective view showing a state in which the cutter unit is removed from the cutter mounting frame. [Figure 4] 10A and 10B are diagrams showing how the moving blade unit is attached to the slider. [Figure 5] FIG. 2 is a perspective view showing the configuration of a slider. [Figure 6] FIG. 2 is a front perspective view of the slider. [Figure 7] FIG. 2 is a block diagram showing the electrical configuration of the multifunction peripheral shown in FIG. [Figure 8] 4 is a time chart showing the control timing when the multifunction peripheral of FIG. 1, particularly the CPU, controls the discharge motor and the cutter motor. [Figure 9] 10A and 10B are diagrams illustrating an example of a transition of a target value of a moving speed until a cutting point of a carriage moves from an initial position to a return position. [Figure 10] 10A and 10B are diagrams showing the carriage cutting point at the origin position, standby position, transport center, and wall contact position on the slide rail. [Figure 11] 10A and 10B are diagrams illustrating the positional relationship between the carriage and the sheet when the cutting point of the carriage has moved to the wall contact position. [Figure 12]10 is a time chart showing the control timing when the MFP according to the second embodiment, particularly the CPU, controls the discharge motor and the cutter motor. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present application will be described in detail with reference to the drawings.

[0013] (First embodiment) FIG. 1 is a cross-sectional view showing a schematic configuration of a multifunction device 1 according to a first embodiment. The multifunction device 1 is an example of an image forming device and has functions such as printing, copying, and scanning. The multifunction device 1 may also have a fax function in addition to these functions. The multifunction device 1 does not necessarily have to have the copying and scanning functions. For ease of explanation, the up-down direction and the front-rear direction of the multifunction device 1 are defined as shown by the arrows in FIG. 1. The left-right direction is defined as the direction to the left of the user facing the multifunction device 1 from the front, and the right-hand direction is defined as the direction to the right. Note that when arrows indicating directions are shown in places other than FIG. 1, the directions should follow the arrows.

[0014] The multifunction device 1 includes a housing 20, a conveying unit 3, a processing unit 4, a fixing unit 6, a scanner unit 9, and a cutter unit 10. The housing 20 is the exterior of the multifunction device 1. The processing unit 4 and the fixing unit 6 correspond to a print engine. The scanner unit 9 is a component used to read documents in the copy function and the scanner function. The conveying unit 3 is an example of a sheet conveying unit. The cutter unit 10 is an example of a sheet cutting device. The housing 20 is formed in a substantially rectangular parallelepiped shape. The multifunction device 1 can form a monochrome image on a sheet S by an electrophotographic method using the print engine. The multifunction device 1 may also be able to form a full-color image on a sheet S by the print engine.

[0015] The multifunction peripheral 1 further has a front cover 21, a rear cover 23, a supply tray 31, a discharge tray 22, a conveying path 201, and a re-conveying path 202. The front cover 21 is attached to the front of the housing 20 in an openable and closable manner. The rear cover 23 is made up of a first rear cover 23A and a second rear cover 23B, and is attached to the rear of the housing 20 in an openable and closable manner. The supply tray 31 is detachably attached to the bottom of the housing 20. Sheets S are placed on the supply tray 31. The sheets S are standard-sized sheets such as A4 size. The sheets S are paper media such as plain paper or cardboard, but are not limited to these, and may also be transparencies. The discharge tray 22 is provided at the top of the housing 20, and sheets S on which images have been formed are placed on the discharge tray 22.

[0016] The transport path 201 is a path for transporting the sheet S placed on the supply tray 31 in a transport direction toward the discharge tray 22 via the process unit 4. The transport path 201 branches into a first discharge path 201A and a second discharge path 201B at a branch position D1. Therefore, the sheet S transported via the process unit 4 may be discharged to the discharge tray 22 via the first discharge path 201A or via the second discharge path 201B.

[0017] The re-conveying path 202 is a path for conveying the sheet S, on one side of which an image has been formed, in the direction opposite to the conveying direction, again toward the process unit 4. The re-conveying path 202 is a path that starts from a switchback position D2 on the first discharge path 201A, which is downstream in the conveying direction from the branching position D1, and ends at a junction position J on the conveying path 201.

[0018] The conveying section 3 has a pickup roller 33, a separation roller 34, a registration roller 35, a conveying roller 36, an upstream cut roller 85, a downstream cut roller 86, a discharge roller 87, a flapper 88, re-conveying rollers 38, 39, a main motor 108 (see Figure 7), and a discharge motor 109 (see Figure 7).

[0019] The pickup roller 33 picks up the sheets S in the supply tray 31 that have been pushed upward by the sheet pressure plate 32, and transports them toward the transport path 201. The separation roller 34 separates the sheets S picked up by the pickup roller 33 one by one.

[0020] The registration rollers 35 are disposed upstream of the process unit 4 on the conveying path 201. The registration rollers 35 align the direction of the leading edge of the sheet S, and then convey the sheet S toward the process unit 4. The conveying rollers 36 convey the sheet S after it has passed through the fixing unit 6 toward the cut upstream rollers 85 or the discharge rollers 87.

[0021] The upstream cutting roller 85 and the downstream cutting roller 86 are disposed on the second discharge path 201B. The upstream cutting roller 85 is disposed at a position upstream of the cutter position SP where the cutter unit 10 is disposed, and the downstream cutting roller 86 is disposed at a position downstream of the cutter position SP.

[0022] The upstream cutting roller 85 is rotated by the driving force from the discharge motor 109 (see FIG. 7). A first driven roller 85' is arranged at a position opposite the upstream cutting roller 85 across the second discharge path 201B. The first driven roller 85' is rotated in accordance with the rotation of the upstream cutting roller 85. The downstream cutting roller 86 is also rotated by the driving force from the discharge motor 109. A second driven roller 86' is arranged at a position opposite the downstream cutting roller 86 across the second discharge path 201B. The second driven roller 86' is rotated in accordance with the rotation of the downstream cutting roller 86.

[0023] The cutting upstream roller 85 and the cutting downstream roller 86 rotate to transport the sheet S in the transport direction, thereby discharging the sheet S onto the discharge tray 22. The rotation to transport the sheet S in the transport direction corresponds to a counterclockwise rotation around the left-right direction of the housing 20 as an axis.

[0024] On the other hand, the discharge roller 87 is disposed on the first discharge path 201A. The discharge roller 87 is rotated by a driving force from a discharge motor 109 (see FIG. 7). A third driven roller 87' is disposed at a position facing the discharge roller 87 across the first discharge path 201A. The third driven roller 87' is rotated in accordance with the rotation of the discharge roller 87. The discharge roller 87 rotates to transport the sheet S in the transport direction, thereby discharging the sheet S onto the discharge tray 22. The discharge roller 87 also rotates in a direction opposite to the rotation that transports the sheet S in the transport direction, thereby transporting the sheet S to the re-conveyance path 202. The rotation in the direction opposite to the rotation that transports the sheet S in the transport direction corresponds to a clockwise rotation about an axis that is the left-right direction of the housing 20.

[0025] Re-conveying rollers 38 and 39 are arranged on the re-conveying path 202. The re-conveying rollers 38 and 39 convey the sheet S conveyed to the re-conveying path 202 toward the process unit 4. The re-conveying rollers 38 and 39 re-convey the sheet S, on one side of which an image has been formed, toward the process unit 4 via the re-conveying path 202, thereby making it possible to form images on both sides of the sheet S.

[0026] The flapper 88 is a member that switches between guiding the sheet S to the first discharge path 201A and guiding the sheet S to the second discharge path 201B. The ASIC 105 (see FIG. 7) switches the direction of current flowing through a flapper solenoid (not shown) to switch the position of the flapper 88 between a first position (position 88A shown by a two-dot chain line in FIG. 1) and a second position (position 88B shown by a solid line in FIG. 1). The first position 88A is a position where the sheet S conveyed by the conveying rollers 36 is guided to the first discharge path 201A. The first position 88A is also a position where the sheet S on the first discharge path 201A is guided to the re-conveyance path 202. The second position 88B is a position where the sheet S conveyed by the conveying rollers 36 is guided to the second discharge path 201B.

[0027] The process unit 4 forms an image on the sheet S and is housed in the housing 20. The process unit 4 has a drum cartridge 5 and a laser unit 7. The drum cartridge 5 has a photosensitive drum 51, a toner storage unit 57, a supply roller 56, a developing roller 55, a charger 52, a transfer roller 53, and a pinch roller 54. The drum cartridge 5 can be removed from the housing 20 by opening the front cover 21. The pinch roller 54 of the drum cartridge 5 faces the registration roller 35. The pinch roller 54 rotates following the rotation of the registration roller 35 and transports the sheet S together with the registration roller 35.

[0028] The photosensitive drum 51 is rotated by a driving force from a main motor 108 (see FIG. 7) to transport the sheet S in the transport direction, thereby transporting the sheet S in the transport direction. The photosensitive drum 51 rotates clockwise around an axis that extends in the left-right direction of the housing 20. Toner is stored in the toner storage section 57. The supply roller 56 supplies the toner in the toner storage section 57 to the developing roller 55. The charger 52 is a scorotron charger that uniformly charges the surface of the photosensitive drum 51. The charger 52 may be a charging roller.

[0029] A transfer roller 53 is disposed at a position facing the photosensitive drum 51. The transfer roller 53 forms a transfer nip TN between itself and the photosensitive drum 51 on the transport path 201. Note that a transfer belt may be used instead of the transfer roller 53.

[0030] The housing 20 has a laser unit 7 at its upper part. The laser unit 7 has a polygon mirror, a laser emitting unit, a polygon motor, a lens, a reflecting mirror, etc. (not shown). The laser unit 7 exposes the surface of the photosensitive drum 51 by scanning the surface of the photosensitive drum 51 at high speed with laser light (see the two-dot chain line in FIG. 1) based on image data emitted from the laser emitting unit.

[0031] An electrostatic latent image based on image data is formed on the surface of the photosensitive drum 51 by exposing it to light with the laser unit 7. The developing roller 55 supplies toner to the electrostatic latent image formed on the surface of the photosensitive drum 51, thereby forming a toner image on the surface of the photosensitive drum 51.

[0032] A transfer voltage is applied to the transfer roller 53 by a high-voltage power supply board (not shown). The transfer roller 53 transports the sheet S between itself and the photosensitive drum 51, thereby transferring the toner image formed on the surface of the photosensitive drum 51 onto the sheet S passing through the transfer nip TN. In this way, an image is formed on the sheet S.

[0033] The fixing unit 6 is disposed downstream of the process unit 4 on the conveying path 201. The fixing unit 6 has a heating roller 61, a pressure roller 62, and a heater 63. The heating roller 61 heats the sheet S. The pressure roller 62 forms a nip N between itself and the heating roller 61 and applies pressure to the sheet S. The pressure roller 62 rotates by the driving force of the main motor 108 to convey the sheet S in the conveying direction. The pressure roller 62 rotates counterclockwise around an axis that corresponds to the left-right direction of the housing 20 to convey the sheet S in the conveying direction. The heater 63 is, for example, a halogen heater, and heats the heating roller 61.

[0034] The fixing device 6 heats the sheet S with the heating roller 61 and rotates the pressure roller 62, thereby conveying the sheet S while applying pressure with the heating roller 61 and the pressure roller 62, thereby fixing the image formed on the sheet S by the process unit 4 to the sheet S.

[0035] A cutter unit 10 is disposed between the upstream cutting roller 85 and the downstream cutting roller 86 in the second discharge path 201B. The cutter unit 10 is disposed downstream of the fixing unit 6 in the conveyance direction of the sheet S. When the position on the sheet S to be cut reaches the cutter position SP, the multifunction device 1 stops the rotation of the upstream cutting roller 85 and the downstream cutting roller 86. With the rotation of the upstream cutting roller 85 and the downstream cutting roller 86 stopped, the multifunction device 1 cuts the sheet S using the cutter unit 10.

[0036] 2 shows the cutter unit 10 mounted between cutter mounting frames 40A and 40B. The cutter mounting frames 40A and 40B to which the cutter unit 10 is mounted are suspended from left and right main body frames (neither of which is shown) that are erected inside the housing 20.

[0037] FIG. 3 shows the cutter unit 10 removed from the cutter mounting frames 40A and 40B. As shown in FIG. 3, the cutter unit 10 includes a cutter frame 11, slide rails 12, a fixed blade 13, a sheet passage 14, a movable blade 15, a carriage 16, a cutter motor 106, and an encoder 113. The cutter motor 106 is an example of a drive motor. The cutter frame 11 extends in the sheet width direction (left-right direction). The slide rails 12 are rails formed on the cutter frame 11 and extend in the sheet width direction. The fixed blade 13 is a flat blade fixed to the cutter frame 11 and extends in the sheet width direction. The sheet passage 14 is a space formed in the cutter frame 11 through which the sheet S passes. The sheet width direction is the conveyance direction of the sheet S, i.e., a direction perpendicular to the direction in which the sheet S passes through the sheet passage 14 and is conveyed from the rear side (upstream side) to the front side (downstream side) of the cutter unit 10 in FIG. 2.

[0038] The carriage 16 is composed of a moving blade holder 16A shown in Fig. 4(a) and a slider 16B shown in Fig. 4(b). As shown in Fig. 4(a), the moving blade holder 16A rotatably holds the moving blade 15, which is a disk-shaped blade. As shown in Fig. 4(b), the slider 16B engages with the slide rail 12 and is attached to the cutter frame 11 so as to be slidable along the slide rail 12.

[0039] The slider 16B holds the moving blade holder 16A in a replaceable manner. Fig. 4(c) shows the state before the moving blade holder 16A is held by the slider 16B, and Fig. 4(d) shows the state after the moving blade holder 16A is held by the slider 16B.

[0040] As shown in Fig. 5, the slider 16B is mainly composed of a slider main body 161 and an opening / closing cover 162. Fig. 5(a) shows the slider main body 161 with the opening / closing cover 162 removed, and Fig. 5(b) shows the slider main body 161 with the opening / closing cover 162 attached. The slider main body 161 is made of, for example, glass fiber-reinforced engineering plastic, and the opening / closing cover 162 is made of, for example, POM (polyoxymethylene). Of course, the present invention is not limited to this.

[0041] The slider body 161 has a peripheral wall 161A composed of a right side wall 161A1, a rear side wall 161A2, and a left side wall 161A3. The peripheral wall 161A is open at the front, top, and bottom. A protrusion 161B1 is formed at the top of the front end of the right side wall 161A1, and a cylindrical bearing portion 161C1 is formed at the bottom of the front end of the right side wall 161A1. Furthermore, a protrusion 161E that protrudes to the right is formed at the rear of the right side wall 161A1. Two inclined surfaces 161E1 that rise toward the rear are formed on the underside of the protrusion 161E. The number of inclined surfaces 161E1 is not limited to two, and may be one, three, or more. The function of the inclined surfaces 161E1 will be described later with reference to FIG. 11. Similar to the right wall 161A1, the left side wall 161A3 has a protrusion 161B2 formed at the upper part of the front end thereof, and a cylindrical bearing portion 161C2 formed at the lower part of the front end thereof. Furthermore, the rear side wall 161A2 has an engagement portion 161D that engages with the slide rail 12, and the inside of the rear side wall 161A2 is configured to be able to accommodate a leaf spring 164. When the moving blade holder 16A is held by the slider 16B, the leaf spring 164 biases the moving blade holder 16A to prevent the moving blade holder 16A from rattling.

[0042] The openable cover 162 has a peripheral wall 162A consisting of a right side wall 162A1, a front side wall 162A2, a left side wall 162A3, and a top wall 162A4. A pivot shaft 162B1 is formed at the bottom of the rear end of the right side wall 162A1, and a pivot shaft 162B2 is formed at the bottom of the rear end of the left side wall 162A3. The inside of the front side wall 162A2 is configured to be able to accommodate two leaf springs 165A and 165B.

[0043] Rotation shafts 162B1 and 162B2 of the open-close cover 162 are fitted into and pivotally supported by bearings 161C1 and 161C2 of the slider body 161, respectively. This allows the open-close cover 162 to swing relative to the slider body 161. When the open-close cover 162 is fixed to the slider body 161, the open-close cover 162 is brought close to the slider body 161. As a result, claws 165A1 and 165B1 formed on the upper portions of the leaf springs 165A and 165B, respectively, are engaged with protrusions 161B1 and 161B2 of the slider body 161, and the open-close cover 162 is fixed to the slider body 161. FIG. 6 shows a state in which the open-close cover 162 is fixed to the slider body 161. However, in the example of FIG. 6, the moving blade holder 16A is not held by the slider 16B. 6 also shows abutment portion 162C formed on left side wall 162A3 of opening / closing cover 162. Note that abutment portion 162C may be formed on, for example, left side wall 161A3 of slider main body 161, rather than on opening / closing cover 162. The function of abutment portion 162C will be described later with reference to FIG.

[0044] Next, the electrical configuration of the multifunction device 1 will be described with reference to Fig. 7. As shown in Fig. 7, the multifunction device 1 further includes an ASIC 105, a ROM 102, a RAM 103, an NVRAM 104, a discharge front sensor SE1, a cut discharge sensor SE2, and a communication interface (I / F) 130.

[0045] ASIC 105 is equipped with CPU 101. CPU 101 is an example of a control unit, and performs overall control of each unit of multifunction device 1. ASIC 105 is electrically connected to ROM 102, RAM 103, NVRAM 104, cutter motor 106, electromagnetic clutch 107, main motor 108, discharge motor 109, discharge front sensor SE1, cut discharge sensor SE2, operation panel PA, communication I / F 130, drum cartridge 5, fixing unit 6, and laser unit 7 (not shown in FIG. 7).

[0046] The ROM 102 stores various control programs and various settings for controlling the multifunction peripheral 1. Some or all of these various control programs and various settings may be stored in the NVRAM 104.

[0047] The RAM 103 is used as a working area from which various control programs are read and as a storage area for temporarily storing image data included in a print job. The CPU 101 controls each part of the multifunction peripheral 1 in accordance with the control programs read from the ROM 102 and signals output from various sensors, while storing the processing results in the RAM 103.

[0048] The CPU 101 drives the cutter motor 106 to move the carriage 16, thereby moving the moving blade 15 in the width direction of the sheet S and cutting the sheet S. An encoder 113 is attached to the rotation shaft of the cutter motor 106, and the encoder 113 outputs a signal corresponding to the rotation of the cutter motor 106. The CPU 101 receives the signal output from the encoder 113, and acquires the rotation direction, rotation position, and rotation speed of the cutter motor 106 based on the received signal. This allows the CPU 101 to know where the slide holder 16 is located on the slide rail 12, that is, where the moving blade 15 is located in the sheet width direction.

[0049] The main motor 108 transmits driving force to the pickup roller 33, the registration roller 35, the conveying roller 36, the re-conveying rollers 38 and 39, the pressure roller 62, and the drum cartridge 5. When the CPU 101 drives the main motor 108 to rotate in the forward direction, the driving force is transmitted to the conveying roller 36, the pressure roller 62, the photosensitive drum 51, the developing roller 55, the pickup roller 33, and the registration roller 35. Then, the conveying roller 36, the pressure roller 62, the photosensitive drum 51, the developing roller 55, the pickup roller 33, and the registration roller 35 rotate in a direction to convey the sheet S in the conveyance direction.

[0050] Specifically, the conveying roller 36 and the pressure roller 62 rotate counterclockwise. The photosensitive drum 51 rotates clockwise. The developing roller 55 rotates counterclockwise. The pickup roller 33 rotates counterclockwise. The registration roller 35 rotates counterclockwise.

[0051] On the other hand, even if the CPU 101 drives the main motor 108 in the reverse direction, the driving force is not transmitted to the conveying roller 36, the pressure roller 62, the drum cartridge 5, the pickup roller 33, and the registration roller 35.

[0052] The discharge motor 109 is, for example, a stepping motor, and transmits driving force to the upstream cutting rollers 85 and the downstream cutting rollers 86. When the CPU 101 drives the discharge motor 109 in the forward direction, the upstream cutting rollers 85 and the downstream cutting rollers 86 rotate counterclockwise. As a result, the sheet S is discharged onto the discharge tray 22. On the other hand, when the CPU 101 drives the discharge motor 109 in the reverse direction, the upstream cutting rollers 85 and the downstream cutting rollers 86 rotate clockwise. As a result, the sheet S is transported in the direction opposite to the transport direction.

[0053] Furthermore, the CPU 101 drives the main motor 108 in the forward direction, causing the re-conveying rollers 38 and 39 to rotate clockwise. On the other hand, the CPU 101 drives the main motor 108 in the reverse direction, causing the re-conveying rollers 38 and 39 to rotate clockwise. As a result, the sheet S transported in the direction opposite to the transport direction is transported toward the image forming unit 4 via a re-conveying path 202.

[0054] CPU 101 controls electromagnetic clutch 107. By turning on electromagnetic clutch 107, CPU 101 brings about a state in which the driving force of main motor 108 is transmitted to pickup roller 33, and by turning off electromagnetic clutch 107, CPU 101 brings about a state in which the driving force of main motor 108 is not transmitted to pickup roller 33.

[0055] The discharge front sensor SE1 is disposed between the fixing unit 6 and the conveying rollers 36 on the conveying path 201, and detects the passage of the sheet S. The discharge front sensor SE1 may be a sensor having an actuator that swings when the sheet S comes into contact with it, or an optical sensor. The discharge front sensor SE1 outputs an ON signal when the sheet S is passing, and outputs an OFF signal when the sheet S is not passing. The detection signal from the discharge front sensor SE1 is output to the CPU 101.

[0056] The cut discharge sensor SE2 is disposed between the cutter position SP and the downstream cutter roller 86, and detects the passage of the sheet S. The cut discharge sensor SE2 has the same configuration as the discharge front sensor SE1. A detection signal by the cut discharge sensor SE2 is output to the CPU 101.

[0057] As shown in FIG. 1, the operation panel PA is disposed on the upper surface of the front side of the device main body 2. Since a user operates the operation panel PA from a position in front of the multifunction device 1, the operation panel PA is provided in a position that allows easy operation by the user from the front of the multifunction device 1. The operation panel PA has, for example, a touch panel in which a touchpad and a display are integrally formed, and a key button section. The operation panel PA receives operations from the user and outputs the received information to the CPU 101. For example, the user can set whether or not to cut the sheet S by operating the operation panel PA.

[0058] The communication I / F 130 is connected to a network such as a LAN, and enables connection to an external device such as a PC incorporating a driver for the multifunction device 1. The CPU 101 can receive a print job via the communication I / F 130. The print job includes various information required to form an image on the sheet S, such as image data for image formation, the size and type of the sheet S to be used for image formation, and information on whether or not to cut the sheet S.

[0059] The control process executed by the multifunction device 1 configured as described above from the time when the multifunction device 1 starts transporting the sheet S printed based on a print job to the cutter unit 10 until the sheet S is cut using the cutter unit 10 and discharged into two pieces from the second discharge path 201B to the discharge tray 22 will be described with reference to Figures 8 to 11.

[0060] 8 is a time chart showing the control timing of the multifunction peripheral 1, particularly the CPU 101, controlling the discharge motor 109 and the cutter motor 106. The time chart in FIG. 8 mainly shows the control timing from a point slightly before time T1 when the discharge motor 109 starts to rotate forward. Time T1 is, for example, the point when the output signal of the discharge front sensor SE1 switches from an OFF signal to an ON signal, that is, the point when the discharge front sensor SE1 detects the leading edge of the sheet S in the conveying direction (hereinafter referred to as the "leading edge of the sheet S"). Therefore, before the discharge front sensor SE1 detects the leading edge of the sheet S, the control processes performed by the CPU 101 on the conveying unit 3, the process unit 4, and the fixing unit 6—specifically, the control to start driving the main motor 108, the control to turn on the electromagnetic clutch 107, the control to form and fix an image on the sheet S, the control to switch the flapper 88, and the like—are actually executed, but a description thereof will be omitted.

[0061] At time T1, CPU 101 starts driving discharge motor 109. As a result, the conveyance of sheet S switches from conveyance by main motor 108 to conveyance by discharge motor 109. At this time, flapper 88 is switched to second position 88B, so sheet S is guided from branch position D1 to second discharge path 201B and conveyed. Then, at time T2, when the output signal of cut discharge sensor SE2 switches from an OFF signal to an ON signal, CPU 101 waits until a first time TI1 has elapsed. The first time TI1 is the time assumed by the developer of multifunction peripheral 1 when the position where sheet S should be cut (for example, a halfway position in the conveyance direction of sheet S) reaches cutter position SP after cut discharge sensor SE2 detects the leading edge of sheet S. The time here may be replaced with the amount of movement of sheet S, the amount of rotation or the number of rotations of discharge motor 109, etc.

[0062] At time T3, which is a first time TI1 after time T2, CPU 101 stops driving discharge motor 109. This is because the position where sheet S should be cut should have reached cutter position SP at time T3. Figure 9 is a diagram showing an example of the transition of the target value of the movement speed of cutting point CP, where carriage 16 cuts sheet S, on slide rail 12 as cutting point CP moves from standby position P1 on slide rail 12 to return position P7. As shown in Figure 9, cutting point CP is the left-hand intersection of moving blade 15 and fixed blade 13.

[0063] FIG. 10 shows the main movement positions of the cutting point CP of the carriage 16 on the slide rail 12. FIG. 10(a) shows the case where the cutting point CP of the carriage 16 is at the origin position P0. FIG. 10(b) shows the case where the cutting point CP of the carriage 16 is at the standby position P1. FIG. 10(c) shows the case where the cutting point CP of the carriage 16 is at the conveyance center Pc. FIG. 10(d) shows the case where the cutting point CP of the carriage 16 is at the wall contact position P6. In other words, the cutting point CP of the carriage 16 can move on the slide rail 12 from the origin position to the wall contact position. Note that, when it is determined that the sheet S printed based on the print job will be cut using the cutter unit 10, the CPU 101 starts driving the cutter motor 106 in the forward direction to move the cutting point CP of the carriage 16 from the origin position P0 to the standby position P1.

[0064] In this way, the cutting point CP of the carriage 16 is theoretically movable from the origin position P0 to the return position P7. However, in the multifunction peripheral 1 of this embodiment, even if the CPU 101 controls the cutter motor 106 to move to the return position P7 as a target, as shown in Fig. 3, the left end face of the carriage 16, more specifically, the abutment portion 162C of the left side wall 162A3 of the open-close cover 162 shown in Fig. 6, abuts against the left side wall 40B1 of the cutter mounting frame 40B, which is formed closer to the origin position P0 than the return position P7, so that the cutting point CP stops at the wall abutment position P6 before the return position P7. However, return position P7 is a control position that takes into consideration displacement of the carriage 16 due to load during cutting, etc., and if the cutting point CP of the carriage 16 is moved along the slide rail 12 to the wall contact position P6 when the sheet S is at the cutter position SP, one sheet S will be sandwiched between the fixed blade 13 and the movable blade 15 and cut into two pieces without having to be moved to the return position P7. This is because the length on the slide rail 12 from the standby position P1 to the wall contact position P6 is sufficiently longer than the length of the sheet S in the sheet width direction. The left side wall 40B1 of the cutter mounting frame 40B is an example of a stopper.

[0065] In this embodiment, the processing of the sheet S by the cutter unit 10 is to completely separate the sheet S into two pieces, but this is not limited to this, and the sheet S may be perforated without being completely separated. Furthermore, the number of sheets to be cut is not limited to two, and may be three or more.

[0066] Returning to FIG. 8, the CPU 101 waits until a second time TI2 has elapsed from time T3. The second time TI2 is the time that the developer of the multifunction peripheral 1 assumed would be a good time to wait after stopping the discharge motor 109 before starting the forward rotation of the cutter motor 106. At time T4, which is the second time TI2 after time T3, the CPU 101 starts the forward rotation of the cutter motor 106. In FIG. 9, the position of the cutting point CP on the slide rail 12 at time T3 is set to the standby position P1. This is because, as described above, it is sufficient to move the cutting point CP from the origin position P0 to the standby position P1 at a point before time T3.

[0067] When the center of the sheet S in the sheet width direction passes exactly through the transport center Pc on the slide rail 12 and the sheet S is transported, the right end of the sheet S in the sheet width direction is at position P3 on the slide rail 12, and the left end of the sheet S in the sheet width direction is at position P4 on the slide rail 12. However, when the sheet S is transported with the center of the sheet S in the sheet width direction deviated from the transport center Pc on the slide rail 12, taking into account the maximum value of this deviation, it is assumed that the right end to the left end of the sheet S in the sheet width direction falls within the range from position P2 to position P5.

[0068] Under this assumption, the CPU 101 increases the rotation speed of the cutter motor 106 so that the movement speed of the cutting point CP on the slide rail 12 gradually increases until the cutting point CP reaches position P2 from standby position P1. Then, the CPU 101 controls the rotation speed of the cutter motor 106 to be constant so that the movement speed of the cutting point CP on the slide rail 12 is maintained at a constant speed until the cutting point CP reaches position P5 from position P2. Furthermore, the CPU 101 reduces the rotation speed of the cutter motor 106 so that the movement speed of the cutting point CP on the slide rail 12 gradually decreases from the constant speed until the cutting point CP reaches position P5 from position P5 to return position P7. As described above, the abutment portion 162C of the carriage 16 abuts against the left wall 40B1 of the cutter mounting frame 40B before the cutting point CP reaches return position P7, so the cutting point CP stops at wall abutment position P6, which is before return position P7. That is, the CPU 101 sets the return position P7 as the target position to be reached by the break point CP, but the break point CP stops at the wall contact position P6 before the return position P7. This ensures that the break point CP reaches the wall contact position P6 even if the amount of movement of the break point CP on the slide rail 12 varies due to, for example, variations in parts, the cutting load, etc.

[0069] The reason why the moving speed of the cutting point CP on the slide rail 12 is maintained constant from position P2 until the cutting point CP reaches position P5 is that when cutting the sheet S, the moving blade 15 moves at a constant speed to ensure a consistent cutting condition of the sheet S and a uniform cut surface. The reason why the moving speed of the cutting point CP on the slide rail 12 is gradually reduced from a constant speed from position P5 until the cutting point CP reaches return position P7 is to reduce the impact when the contact portion 162C of the carriage 16 contacts the left wall 40B1 of the cutter mounting frame 40B and minimize the generation of impact noise. The generation of impact noise can also be suppressed by the shape of the contact portion 162C, i.e., by having a small contact area and by being made of a soft material such as POM.

[0070] In this way, the CPU 101 controls the rotation of the cutter motor 106 based on the position of the cutting point CP on the slide rail 12, and the CPU 101 can know the position of the cutting point CP on the slide rail 12 based on the output signal from the encoder 113, as described above.

[0071] Returning to Figure 8, the CPU 101 controls the forward rotation of the cutter motor 106 as described with reference to Figure 9 between time T4 and time T5. Then, at time T5, the CPU 101 stops the forward rotation of the cutter motor 106. Note that the period from time T4 to time T5 is not a predetermined period. In other words, time T5 is the time at which the CPU 101 determines, based on the output signal from the encoder 113, that the cutting point CP has reached the wall contact position P6 and has stopped moving, and therefore the time varies depending on the control situation.

[0072] FIG. 11(a) is a schematic diagram showing a state in which the contact portion 162C of the carriage 16 contacts the left side wall 40B1 of the cutter mounting frame 40B. In this state, the sheet S is cut into two sheet pieces by the moving blade 15 and the fixed blade 13. The sheet piece S2 shown in FIG. 11(a) is the upstream one of the two sheet pieces. The left end S21 of the sheet piece S2 is vertically overlapped with the lower surface of the protruding portion 163. Conversely, the left side wall 40B1 of the cutter mounting frame 40B is positioned so that, when the contact surface 162B of the carriage 16 contacts the left side wall 40B1 of the cutter mounting frame 40B, the lower surface of the protruding portion 163 is vertically overlapped with the left end of the sheet piece S2.

[0073] 11(b) is a schematic diagram of the sheet piece S2 on the upstream side in the conveyance direction of the sheet S. As shown in FIG. 11(b), when the curled sheet S is cut by the moving blade 15 and the fixed blade 13, the leading end S22 of the upstream sheet piece S2 may curl upward. The inclined surface 161E1 can suppress the curl of the leading end S22 of the sheet piece S2. As will be described later with reference to FIG. 8 again, the sheet piece S2 passes through the cutter unit 10 and is discharged to the discharge tray 22 from the second discharge path 201B. When conveyance of the sheet piece S2 begins, the curl of the leading end S22 of the sheet piece S2 is suppressed downward by the inclined surface 161E1, which rises toward the rear side, in other words, the inclined surface 161E1, which rises toward the upstream side in the conveyance direction of the sheet S. This minimizes jamming that may occur when the upward curl at the front end S22 of the sheet piece S2 comes into contact with the cutter unit 10 or the second discharge path 201B before the sheet piece S2 is discharged to the discharge tray 22.

[0074] 11(c) shows a case where the protruding portion 170 without the inclined surface 161E1 is formed on the slider body 161. In this case, when conveyance of the sheet piece S2 starts, the upward curl of the front end of the sheet piece S2 comes into contact with the protruding portion 170, as shown in FIG. 11(c), and a jam is likely to occur.

[0075] 8, at time T5, the CPU 101 stops the forward rotation of the cutter motor 106 and then waits until a third time TI3 has elapsed. The third time TI3 is the time that the developer of the multifunction peripheral 1 assumed was appropriate to wait between stopping the forward rotation of the cutter motor 106 and starting the forward rotation of the discharge motor 109. At time T6, which is the third time TI3 after time T5, the CPU 101 resumes the forward rotation of the discharge motor 109.

[0076] At time T6, the sheet S has been cut into two sheet pieces by the cutter unit 10. Therefore, both sheet pieces are discharged from the second discharge path 201B to the discharge tray 22. While these two sheet pieces are being discharged, a gap is formed between the downstream sheet piece and the upstream sheet piece. Between time T7 and time T8, the cut discharge sensor SE2 outputs an OFF signal. This is because the cut discharge sensor SE2 detects a gap between the downstream sheet piece and the upstream sheet piece. This gap is formed by the speed difference between the cutting upstream roller 85 and the cutting downstream roller 86. Then, at time T9, when the output signal of the cut discharge sensor SE2 switches from an ON signal to an OFF signal, the CPU 101 waits until a fourth time TI4 has elapsed. The fourth time TI4 is the time assumed by the developer of the multifunction peripheral 1 for the upstream sheet piece to be discharged to the discharge tray 22 after the cut discharge sensor SE2 detects the trailing edge of the upstream sheet piece. At time T10, which is the fourth time TI4 after time T9, the CPU 101 stops the forward rotation of the discharge motor 109. Note that the same control is performed when the output signal of the cut discharge sensor SE2 switches from an ON signal to an OFF signal at time T7, but because the time from time T7 to time T8 is shorter than the fourth time TI4, the CPU 101 does not stop the forward rotation of the discharge motor 109.

[0077] The CPU 101 then waits until a fifth time TI5 has elapsed. The fifth time TI5 is the time that the developer of the multifunction peripheral 1 assumed would be best to wait after stopping the discharge motor 109 before starting the reverse rotation of the cutter motor 106. At time T11, when the fifth time TI5 has elapsed since time T10, the CPU 101 starts the reverse rotation of the cutter motor 106. Thereafter, the CPU 101 continues the reverse rotation of the cutter motor 106 until time T12. At time T12, the CPU 101 stops the reverse rotation of the cutter motor 106. When the reverse rotation of the cutter motor 106 continues from time T11 to time T12, the carriage 16 returns from the wall abutment position to the standby position. Subsequently, if cut printing is not performed using the print job, the carriage 16 may be returned to the origin position. When returning the carriage 16 from the wall-contacting position to the standby position or the origin position, the constant speed control of the carriage 16 and the subsequent deceleration control that were performed when moving the carriage 16 from the standby position to the wall-contacting position do not need to be performed.

[0078] As described above, the cutter unit 10 of this embodiment has the fixed blade 13 extending in the sheet width direction perpendicular to the conveying direction of the sheet S, the movable blade 15 in sliding contact with the fixed blade 13, the carriage 16 movable in the sheet width direction, and the left side wall 40B1 of the cutter mounting frame 40B provided at one end of the carriage 16 in the moving direction and capable of abutting against the left side wall 40B1 of the cutter mounting frame 40B. and a protrusion 161E that is provided at least upstream of the moving blade 15 in the conveying direction of the sheet S and protrudes toward the other end side in the moving direction of the carriage 16, and the left side wall 40B1 of the cutter mounting frame 40B is positioned so that when the abutment portion 162C of the carriage 16 abuts against the left side wall 40B1 of the cutter mounting frame 40B, the protrusion 161E of the carriage 16 overlaps with a part of the passing range through which the sheet S passes when being conveyed.

[0079] Thus, in the cutter unit 10 of this embodiment, the protrusion 161E does not come off the sheet S2 upstream of the cutting position even when it is stopped after cutting, and serves as a guide when returning and when conveying the sheet, so there is no risk of it colliding with the side of the sheet S and deforming the sheet S, and there is no risk of the sheet S colliding with the carriage 16 when conveying the sheet S. Furthermore, because part of the carriage 16 stops at a position overlapping with the passing range of the sheet S, it is possible to keep the sheet width to the minimum necessary.

[0080] The cutter unit 10 further includes a cutter motor 106 that drives the carriage 16 to reciprocate in the sheet width direction, and a CPU 101 that controls the driving of the cutter motor 106, and when the carriage 16 is moved toward one end of the moving direction of the carriage 16, the CPU 101 controls the cutter motor 106 so that the carriage 16 moves at a constant speed within the passing range of the sheet S (the range from position P2 to position P5 in FIG. 9) and decelerates the carriage 16 after the moving blade 15 has passed through the passing range. This prevents speed fluctuations while the sheet S is being cut, ensuring stable cutting performance of the moving blade 15.

[0081] Furthermore, when moving carriage 16 toward one end of the movement direction of carriage 16, CPU 101 sets the amount of movement toward that end (the amount of movement to return position P7 in FIG. 9) to be greater than the amount of movement required for carriage 16 to abut against left side wall 40B1 of cutter mounting frame 40B (the amount of movement to wall abutment position P6 in FIG. 9), and stops cutter motor 106 when carriage 16 abuts against left side wall 40B1 of cutter mounting frame 40B. This allows carriage 16 to reliably abut against left side wall 40B1 of cutter mounting frame 40B even if the amount of movement of carriage 16 changes due to component variations, cutting load, etc.

[0082] Furthermore, when the carriage 16 is in contact with the left side wall 40B1 of the cutter mounting frame 40B, the intersection (cutting point CP) between the moving blade 15 and the fixed blade 13 is located outside the range through which the sheet S passes (FIG. 11(a)). This prevents the cutting blade from interfering with the conveyance of the sheet S.

[0083] The cutter unit 10 further includes a slide rail 12 that guides the carriage 16 in the sheet width direction, the carriage 16 having a moving blade holder 16A that rotatably holds the moving blade 15, and a slider 16B that holds the moving blade holder 16A and engages with the slide rail 12, and the protrusion 161E and the abutment portion 162C are provided on the slider 16B. Because the slider 16B is rigid, providing the abutment portion 162C on the slider 16B can prevent deformation due to impact when the slider 16B abuts against the left wall 40B1 of the cutter mounting frame 40B.

[0084] The slider 16B replaceably holds the moving blade holder 16A and includes a slider body and an openable cover 162 that swings relative to the slider body 161, with the abutment portion 162C provided on the openable cover 162 and the protrusion 161E provided on the slider body 161. By providing the openable cover 162 with the abutment portion 162C in this manner, damage to components due to a collision with the left side wall 40B1 of the cutter mounting frame 40B can be prevented. For example, if the slider body 161 were made of glass-filled engineering plastic, as in this embodiment, there is a risk of chipping due to impact, but if the openable cover 162 is made of POM or the like, damage will not occur.

[0085] Furthermore, protrusion 161E is provided on the other end side of moving blade 15 in the movement direction of carriage 16, and the portion of moving blade 15 that protrudes downward below the upper surface of fixed blade 13 is characterized in that it is positioned between the passage range of sheet S and the left side wall 40B1 of cutter mounting frame 40B when abutment portion 162C of carriage 16 abuts against left side wall 40B1 of cutter mounting frame 40B. As a result, even when protrusion 161E protrudes into the movement range of sheet S, moving blade 15 is outside the movement range of sheet S, so that carriage 16 can be stopped with certainty when cutting is completed.

[0086] The protrusion 161E is characterized in that it has an inclined surface 161E1 that rises toward the upstream side in the conveyance direction of the sheet S, on the underside of the carriage 16 upstream of the moving blade 15 in the conveyance direction of the sheet S. This makes it difficult for the protrusion 161E to hit the sheet S even if the sheet S is deformed.

[0087] As described above, the multifunction device 1 of this embodiment is equipped with a cutter unit 10 and a conveying section 3 that conveys a sheet S, and the CPU 101 further controls the conveying section 3, and when cutting a sheet S with the cutter unit 10, causes the conveying section 3 to convey the sheet to the cutter unit 10 and stop it, moves the carriage 16 to one end side of the movement direction of the carriage 16 to cut the sheet S, and then controls the cutter motor 106 to control the cutter motor 106 so that the conveying section 3 resumes conveying the sheet S with the abutment portion 162C abutting against the left side wall 40B1 of the cutter mounting frame 40B, and moves the carriage 16 to the other end side of the movement direction of the carriage 16 after the rear end of the sheet S2 remaining upstream of the fixed blade 13 in the conveying direction of the sheet S passes the fixed blade 13.

[0088] As a result, the moving blade 15 is returned after the cut sheet S is discharged, so there is no risk of the sheet S coming into contact with the carriage 16. In addition, since the upstream sheet S2 and the carriage 16 are in an overlapping state, the sheet S does not jam when being conveyed.

[0089] (Second embodiment) Next, a second embodiment will be described. The only difference between this embodiment and the first embodiment is the timing at which the carriage 16 is returned from the wall-contact position to the standby position or the origin position. Therefore, the following description will focus on the differences, and descriptions of other parts will be omitted as appropriate. Furthermore, the hardware used in the first embodiment, specifically the hardware shown in Figures 1 to 6, will be used as is for this embodiment.

[0090] 11 is a time chart showing the control timing of the multifunction peripheral 1 according to the embodiment, particularly the CPU 101, controlling the discharge motor 109 and the cutter motor 106. In FIG. 11, the same timing as in FIG. 7 is denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0091] 11, at time T5, the CPU 101 stops the forward rotation of the cutter motor 106. Thereafter, the CPU 101 waits until a sixth time TI6 has elapsed. The sixth time TI6 is the time that the developer of the multifunction peripheral 1 assumed would be a good time to wait between stopping the forward rotation of the cutter motor 106 and starting the reverse rotation of the cutter motor 106. At time T21, which is the sixth time TI6 after time T5, the CPU 101 starts the reverse rotation of the cutter motor 106. The control processing performed by the CPU 101 from time T21 to time T22 is the same as the control processing performed from time T11 to time T12 in the first embodiment, and therefore will not be described again here.

[0092] At time T22, the CPU 101 stops the reverse rotation of the cutter motor 106 and waits until a seventh time TI7 has elapsed. The seventh time TI7 is the time that the developer of the multifunction peripheral 1 assumed was appropriate to wait after stopping the reverse rotation of the cutter motor 106 before resuming the forward rotation of the discharge motor 109. At time T23, which is the seventh time TI7 after time T22, the CPU 101 resumes the forward rotation of the discharge motor 109. The control process for the discharge motor 109 that the CPU 101 performs after time T23 is similar to the control process for the discharge motor 109 that is performed after time T6 in the first embodiment, and therefore will not be described again here.

[0093] As described above, the multifunction device 1 of this embodiment is equipped with a cutter unit 10 and a conveying section 3 that conveys the sheet S, and the CPU 101 further controls the conveying section 3, and when the cutter unit 10 cuts the sheet S, the conveying section 3 conveys the sheet S to the cutting position and stops it, and controls the cutter motor 106 to move the carriage 16 to one end of the movement direction of the carriage 16 to cut the sheet S, and then controls the carriage 16 to the other end of the movement direction of the carriage 16, and when the moving blade 15 has moved out of the passing range of the sheet S, the conveying section 3 resumes conveying the sheet S.

[0094] As a result, when the moving blade 15 moves back, the sheet S and the carriage 16 are in an overlapping position, and there is no risk of the edge of the sheet S coming into contact with the edge of the carriage 16. Also, since the moving blade 15 is in a position outside the range through which the sheet S passes, the sheet S does not jam when it is conveyed.

[0095] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0096] (1) In the above embodiments, the multifunction peripheral 1 is given as an example of an image forming apparatus, but the image forming apparatus is not limited to the multifunction peripheral 1 and may be a standalone printer or copier. In the above embodiments, the multifunction peripheral 1 is given as an example of an image forming apparatus that prints on sheets S using an electrophotographic method, but the image forming apparatus may be a printing device that prints on sheets S using an inkjet method.

[0097] (2) In each of the above embodiments, examples have been described in which the processes shown in Figures 7 and 11 are executed by CPU 101. However, these processes may be executed not only by CPU 101 but also by ASIC 105 or other logic integrated circuits, or these processes may be executed by cooperation between CPU 101, ASIC 105, and other logic integrated circuits.

[0098] (3) In the above embodiments, the drive control and stop control of the discharge motor 109 are based on time. However, this is not limited to this. Depending on the type of motor used, the drive control and stop control may be based on factors other than time, specifically, the number of steps input to the stepping motor or the signal output from the encoder, such as a step signal.

[0099] (4) In the above embodiments, the sheet S is cut by the moving blade 15 when the carriage 16 is moved from the standby position to the wall contact position, that is, when it is moved in one direction. However, this is not limiting, and the sheet S may also be cut when it is returned from the wall contact position to the standby position. In this case, the sheet S may be cut on both the forward and backward paths.

[0100] (5) In the above embodiments, the left side wall 40B1 of the cutter mounting frame 40B is given as an example of a stopper for the carriage 16. In other words, a member that is not included in the cutter unit 10 is used as the stopper, but the stopper may be provided within the cutter unit 10. [Explanation of symbols]

[0101] 1...multifunction device, 3...transport section, 4...process section, 10...cutter unit, 12...slide rail, 13...fixed blade, 14...sheet passing section, 15...moving blade, 16...carriage, 16A...moving blade holder, 16B...slider, 20...casing, 40A, 40B...cutter mounting frame, 40B1...left side wall, 85...upstream cut roller, 85'...first driven roller, 86...downstream cut roller, 86'...second driven roller, 87...discharge roller, 87'...third driven roller, 101 ...CPU, 102...ROM, 103...RAM, 104...NVRAM, 105...ASIC, 106...cutter motor, 109...discharge motor, 113...encoder, 161...slider body, 162...opening / closing cover, 162C...contact portion, 161E...protrusion, 161E1...inclined surface, 201...conveying path, 201A...first discharge path, 201B...second discharge path, CP...cutting point, D1...branching position, S...sheet, SE1...discharge front sensor, SE2...cut discharge sensor.

Claims

1. a fixed blade extending in a sheet width direction perpendicular to a sheet conveyance direction; a carriage having a movable blade that is in sliding contact with the fixed blade and that is movable in the sheet width direction; a stopper provided at one end of the carriage in the moving direction, the stopper preventing the carriage from moving; Equipped with The carriage includes: a contact portion provided on the one end side in the moving direction of the carriage and capable of contacting the stopper; a protruding portion provided at least upstream of the moving blade in the sheet conveying direction and protruding toward the other end of the carriage in the moving direction; and The stopper is the protrusion of the carriage is disposed so as to overlap a part of a passing range through which the sheet passes when being conveyed, when the abutting portion of the carriage abuts against the stopper; A sheet cutting device characterized by:

2. The sheet cutting device further comprises: a drive motor that drives the carriage so as to be reciprocable in the sheet width direction; a control unit that controls the driving of the drive motor; Equipped with The control unit When the carriage is moved toward the one end side in the moving direction of the carriage, the drive motor is controlled so that the carriage is moved at a constant speed within the passing range of the sheet, and the carriage is decelerated after the moving blade has passed through the passing range.

2. The sheet cutting device according to claim 1.

3. The control unit when moving the carriage toward the one end in the moving direction of the carriage, the amount of movement toward the one end is set to be greater than the amount of movement required for the carriage to abut against the stopper, and the drive motor is stopped in a state where the carriage abuts against the stopper; 3. The sheet cutting device according to claim 2.

4. When the carriage is in contact with the stopper, the intersection of the moving blade and the fixed blade is located outside the passing range of the sheet.

4. The sheet cutting device according to claim 3.

5. The sheet cutting device further comprises: a guide portion that guides the carriage in the sheet width direction; Equipped with The carriage includes: a moving blade holder that rotatably holds the moving blade; a slider that holds the moving blade holder and engages with the guide portion; and The protrusion and the abutment are provided on the slider.

2. The sheet cutting device according to claim 1.

6. The slider holds the moving blade holder in a replaceable manner, A slider body; an open / close cover that swings relative to the slider body; and The abutment portion is provided on the openable cover, The protrusion is provided on the slider body.

6. The sheet cutting device according to claim 5.

7. the protruding portion is provided closer to the other end in the moving direction of the carriage than the moving blade, a portion of the movable blade that protrudes downward from an upper surface of the fixed blade is positioned between the passage area of ​​the sheet and the stopper when the contact portion of the carriage contacts the stopper; 2. The sheet cutting device according to claim 1.

8. The sheet cutting device according to any one of claims 2 to 4, a sheet conveying unit that conveys a sheet; Equipped with the control unit further controls the sheet conveying unit; When cutting the sheet by the sheet cutting device, the sheet is conveyed to a cutting position by the sheet conveying unit and stopped, the carriage is moved to the one end side in the moving direction of the carriage to cut the sheet, and then, with the abutting portion abutting against the stopper, the sheet conveying unit resumes conveying the sheet, and the drive motor is controlled so that, after the rear end of the sheet remaining upstream of the fixed blade in the conveying direction of the sheet has passed the fixed blade, the carriage is moved to the other end side in the moving direction of the carriage. An image forming apparatus characterized by:

9. The sheet cutting device according to any one of claims 2 to 4, a sheet conveying section that conveys the sheet; Equipped with the control unit further controls the sheet conveying unit; When cutting the sheet by the sheet cutting device, the sheet conveying unit conveys the sheet to a cutting position and stops the sheet, the carriage is moved to the one end side in the moving direction of the carriage to cut the sheet, and then the drive motor is controlled to move the carriage to the other end side in the moving direction of the carriage, and the sheet conveying unit resumes conveying the sheet in a state where the moving blade has moved out of the passing range of the sheet. An image forming apparatus characterized by:

10. the protrusion included in the sheet cutting device has an inclined surface on a lower surface of the carriage upstream of the moving blade in the sheet conveying direction, the inclined surface rising toward the upstream side in the sheet conveying direction, 10. The image forming apparatus according to claim 8, wherein the image forming apparatus is a recording medium.

Images