Image formation device

Abstract

To provide an image formation device that can implement only cutting without performing image formation on a sheet.SOLUTION: An image formation device comprises a device body, an image formation unit, a cutter, a discharge tray, and a control unit. The cutter is arranged downstream with respect to the image formation unit in a sheet conveyance direction. The control unit determines whether any of a print cutting mode of performing image formation on the sheet and cutting the sheet, and a mode of cutting the sheet only without performing the image formation on the sheet is selected, and can implement the determined mode. When implementing the print cutting mode (S3,No) (S4,No), the control unit implements, by the image formation unit, to perform the image formation on the sheet and cut the sheet by the cutter. When implementing the mode of cutting the sheet only (S3,Yes) (S4,Yes), the control unit cuts the sheet by the cutter without forming the image on the sheet (S15) (S9).SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an image forming apparatus provided with a cutter.

Background Art

[0002] Conventionally, an image forming apparatus provided with a cutter has been known (Patent Document 1). This image forming apparatus can cut one sheet into two sheets when it is determined that cutting of the sheet is necessary.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Conventionally, in an image forming apparatus provided with a cutter, it has been set to perform image formation on a sheet and then cut the sheet, and there has been no setting that allows only cutting to be performed without forming an image on the sheet.

[0005] Therefore, an object of the present invention is to provide an image forming apparatus that can perform only cutting without forming an image on a sheet.

Means for Solving the Problems

[0006] An image forming apparatus for achieving the above object includes an apparatus main body, an image forming unit, a cutter, a discharge tray, and a control unit. The image forming unit is disposed in the apparatus main body and forms an image on a sheet. The cutter is disposed downstream of the image forming unit in the sheet conveyance direction. The cutter can cut the sheet in a crossing direction that crosses the conveyance direction. The discharge tray is where the sheet is discharged. The control unit determines which of the printing and cutting mode, in which an image is formed on a sheet and the sheet is cut, and the cutting-only mode, in which the sheet is cut without forming an image on the sheet, is selected, and the determined mode is executable. When the control unit executes the printing and cutting mode, it forms an image on the sheet with the image forming unit and cuts the sheet with the cutter. When the control unit executes the cutting-only mode, it cuts the sheet with the cutter without forming an image on the sheet.

[0007] When the control unit executes the cutting-only mode, it cuts the sheet with the cutter without forming an image on the sheet. Therefore, in an image forming apparatus including an image forming unit and a cutter, only cutting can be executed without forming an image on the sheet.

[0008] Further, it may further include a supply tray for accommodating the sheet. Then, the control unit may control such that the preparation operation time from receiving a command to execute the cutting-only mode until starting the conveyance of the sheet from the supply tray is shorter than the preparation operation time from receiving a command to execute the printing and cutting mode until starting the conveyance of the sheet from the supply tray.

[0009] When the control unit executes the cutting-only mode, in order to control so that the preparation operation time is shorter compared to the case of executing the printing and cutting mode, it can start operating earlier compared to the case of executing the printing and cutting mode.

[0010] Further, the image forming apparatus may further include a supply tray for accommodating the sheet. And the image forming unit may further have a fixing device for fixing the toner image on the sheet by heating the sheet on which the toner image is transferred. And when the control unit executes the printing and cutting mode, it may start supplying the sheet from the supply tray on the condition that the fixing device is at a first temperature or higher. And when the control unit executes the cutting-only mode, it may start supplying the sheet from the supply tray on the condition that the fixing device is at a second temperature or higher which is lower than the first temperature.

[0011] When executing the cut-only mode, the supply of the sheet from the supply tray is started on the condition that the fixing device is at a temperature equal to or higher than a second temperature that is lower than the first temperature. Therefore, when executing the cut-only mode, the operation can be started earlier than when executing the print-cut mode.

[0012] Also, when executing the cut-only mode, the control unit may be capable of executing either a speed-priority mode that prioritizes the speed until sheet ejection or an accuracy-priority mode that prioritizes the dimensional accuracy of the sheet to be cut. And when executing the accuracy-priority mode, the control unit may start the supply of the sheet from the supply tray on the condition that the temperature of the fixing device is equal to or lower than a third temperature that is equal to or higher than the second temperature and lower than the first temperature. And when executing the speed-priority mode, the control unit may start the supply of the sheet from the supply tray even if the temperature of the fixing device is higher than the third temperature as long as it is equal to or higher than the second temperature.

[0013] When executing the accuracy-priority mode, since the sheet is cut after the temperature of the fixing device becomes equal to or lower than the third temperature, the sheet can be cut accurately. Also, when executing the speed-priority mode, since the sheet is cut even if the temperature of the fixing device is higher than the third temperature, the operation can be started earlier.

[0014] Also, it may further include a supply tray for accommodating the sheet. And the image forming unit may be a deflector having a photosensitive drum, a polygon mirror that deflects a beam emitted from a light source, and a polygon motor that rotates the polygon mirror, and a deflector that emits the beam deflected by the polygon mirror to the photosensitive drum. And when executing the print-cut mode, the control unit may rotate the polygon motor and start the supply of the sheet from the supply tray on the condition that the rotation of the polygon motor has stabilized. And when executing the cut-only mode, the control unit may start the supply of the sheet from the supply tray without rotating the polygon motor.

[0015] When executing only the cutting mode, since the feeding of the sheet is started without waiting for the rotation of the polygon motor to stabilize, the operation can be started quickly.

[0016] Further, it may further include a conveyance roller disposed inside the apparatus main body for conveying the sheet, and a conveyance motor for rotating the conveyance roller. And when executing the printing and cutting mode, the control unit may rotate the conveyance motor at a first rotation speed, and when executing only the cutting mode, the control unit may rotate the conveyance motor at a second rotation speed faster than the first rotation speed.

[0017] When executing only the cutting mode, since the conveyance motor is made faster than when executing the printing and cutting mode, the operation can be completed quickly.

[0018] Further, when executing only the cutting mode, the control unit may be capable of executing a speed priority mode that prioritizes the speed until the sheet is discharged, and an accuracy priority mode that prioritizes the dimensional accuracy of the sheet to be cut. And when executing the speed priority mode, the control unit may rotate the conveyance motor at the second rotation speed, and when executing the accuracy priority mode, the control unit may rotate the conveyance motor at a third rotation speed that is equal to or lower than the first rotation speed.

[0019] When executing the speed priority mode, since the conveyance motor is made faster than when executing the accuracy priority mode, the operation can be completed quickly. When executing the accuracy priority mode, since the conveyance motor is made slower than when executing the accuracy priority mode, the sheet can be cut accurately.

[0020] Further, the image forming unit may include a photoreceptor drum, a developing roller that supplies toner to the photoreceptor drum, and a pressure contact and separation mechanism that can press and separate the developing roller with respect to the photoreceptor drum. And when executing the printing and cutting mode, the control unit may press the developing roller against the photoreceptor drum. And when executing only the cutting mode, the control unit may separate the developing roller from the photoreceptor drum.

[0021] When the cut-only mode is executed, since the developing roller is separated from the photosensitive drum, deterioration of the photosensitive drum and the developing roller can be suppressed.

[0022] Further, the image forming unit may be detachable from the apparatus main body and may have a cartridge capable of accommodating consumables for image formation therein. And when the control unit determines that the cartridge is not attached to the apparatus main body, it may be configured to prohibit execution of the print cut mode and not prohibit execution of the cut-only mode.

[0023] Even when the control unit determines that the cartridge is not attached to the apparatus main body, since execution of the cut-only mode is not prohibited, the cut-only mode can be executed even when the cartridge is not attached.

[0024] Further, the image forming unit may have a storage unit in which consumables for image formation are stored. And when the control unit determines that the remaining amount of the consumables in the storage unit is equal to or less than a predetermined amount, it may be configured to prohibit execution of the print cut mode and not prohibit execution of the cut-only mode.

[0025] Even when the control unit determines that the remaining amount of the consumables in the storage unit is equal to or less than a predetermined amount, since execution of the cut-only mode is not prohibited, the cut-only mode can be executed even when the remaining amount of the consumables is equal to or less than a predetermined amount.

[0026] Further, the control unit may control such that the time from receiving a command to execute the cut-only mode until discharging the sheet to the discharge tray is shorter than the time from receiving a command to execute the print cut mode until discharging the sheet to the discharge tray.

[0027] According to this, when the cut-only mode is executed, the operation can be completed earlier as compared with the case of executing the print cut mode.

Effects of the Invention

[0028] According to the present invention, it is possible to provide an image forming apparatus that can execute only cutting without forming an image on a sheet.

Brief Description of the Drawings

[0029]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Modes for Carrying Out the Invention

[0030] Next, embodiments of the present disclosure will be described in detail with reference to the drawings as appropriate. In the following description, the axial direction of the photosensitive drum 51 is referred to as the "axial direction". Also, the discharge direction of the sheet S by the first discharge roller 84 (the direction of the arrow in FIG. 1) is referred to as the "discharge direction". The direction of the arrow in the figure indicates one side. The direction opposite to one side is referred to as the other side.

[0031] As shown in FIG. 1, the image forming apparatus 1 is a laser printer. The image forming apparatus 1 includes an apparatus main body 2, a supply unit 3, an exposure device 4, a drum cartridge 5, a cartridge mounting sensor 5A, a fixing device 6, a cutter unit 7, a sheet conveyance unit 8, an operation panel PA, a first sheet sensor SE1, a second sheet sensor SE2, a third sheet sensor SE3, a fourth sheet sensor SE4, and a control unit CU. The exposure device 4, the drum cartridge 5, and the fixing device 6 are examples of an image forming unit, and form an image on a sheet S.

[0032] The apparatus main body 2 has a front cover 21, a discharge tray 22, a first discharge port 23, and a second discharge port 24. The front cover 21 is located on the downstream side in the discharge direction in the apparatus main body 2. The discharge tray 22 is formed on the upper surface of the apparatus main body 2. The discharge tray 22 is a tray on which the discharged sheet is placed.

[0033] The first discharge port 23 is a discharge port for discharging the sheet S to the outside of the apparatus main body 2. The first discharge port 23 is located below the second discharge port 24. In other words, the first discharge port 23 is located closer to the fixing device 6 described later than the second discharge port 24. In the present embodiment, the first discharge port 23 discharges the sheet S that has not been cut by the cutter unit 7 to the outside of the apparatus main body 2. The sheet S discharged from the first discharge port 23 is placed on the discharge tray 22.

[0034] The second discharge port 24 is a discharge port different from the first discharge port 23 for discharging the sheet S to the outside of the apparatus main body 2. The second discharge port 24 is located above the first discharge port 23 and on the downstream side in the discharge direction. In the present embodiment, the second discharge port 24 mainly discharges the sheet S cut by the cutter unit 7 to the outside of the apparatus main body 2. The sheet S discharged from the second discharge port 24 is placed on the discharge tray 22.

[0035] The supply unit 3 is located inside the apparatus main body 2. The supply unit 3 includes a supply tray 31, a sheet pressing plate 32, a pickup roller 33, a separation roller 34, and a registration roller 35.

[0036] The supply tray 31 is a tray for accommodating the sheet S. The sheet pressing plate 32 pushes up the sheet S in the supply tray 31 upward. The pickup roller 33 picks up the sheet S on the supply tray 31. The separation roller 34 separates the sheets S picked up by the pickup roller 33 one by one. The registration roller 35 conveys the sheet S between the photosensitive drum 51 and the transfer roller 53.

[0037] The exposure device 4 is located at the upper part inside the apparatus main body 2. The exposure device 4 includes a deflector 40 and a light source (not shown). The deflector 40 includes a polygon mirror 41 and a polygon motor 42. The polygon mirror 41 deflects the beam emitted from the light source in the main scanning direction. The polygon motor 42 is a motor that rotates the polygon mirror 41. In this exposure device 4, the laser light based on the image data emitted from the light source is deflected by the polygon mirror 41, and the beam deflected by the polygon mirror 41 is emitted toward the photosensitive drum 51. The emitted beam is scanned at high speed on the surface of the photosensitive drum 51 to expose the surface of the photosensitive drum 51.

[0038] The drum cartridge 5 is detachable from the apparatus main body 2. When the drum cartridge 5 is attached to the apparatus main body 2, the drum cartridge 5 is located below the exposure device 4. The drum cartridge 5 is detached and attached with the front cover 21 open. The cartridge attachment sensor 5A is a sensor that detects whether the drum cartridge 5 is attached to the apparatus main body 2.

[0039] The drum cartridge 5 includes a photosensitive drum 51, a charger 52, a transfer roller 53, a pinch roller 54, a developing roller 55, a supply roller 56, a toner storage section 57, and a toner remaining amount sensor 58.

[0040] The photosensitive drum 51 is rotatable about a drum axis 51X extending in the first direction. The charger 52 charges the surface of the photosensitive drum 51. The transfer roller 53 is positioned opposite to the photosensitive drum 51. The transfer roller 53 transfers the toner image formed on the photosensitive drum 51 onto the sheet S. The charger 52 is a scorotron type charger. The pinch roller 54 is positioned opposite to the registration roller 35. The pinch roller 54 rotates in a driven manner following the rotation of the registration roller 35 and conveys the sheet S together with the registration roller 35. The toner container 57 stores toner as an example of a consumable for image formation inside. The toner remaining amount sensor 58 is a sensor capable of detecting whether the remaining amount of toner in the toner container 57 is below a predetermined amount.

[0041] The developing roller 55 supplies toner to the photosensitive drum 51 while being in contact with the photosensitive drum 51. The supply roller 56 supplies the toner in the toner container 57 to the developing roller 55.

[0042] In the drum cartridge 5, the surface of the photosensitive drum 51 is uniformly charged by the charger 52. Thereafter, by exposing the surface of the photosensitive drum 51 by high-speed scanning of the laser beam from the exposure device 4, an electrostatic latent image based on the image data is formed on the photosensitive drum 51. The toner carried on the developing roller 55 is supplied from the developing roller 55 to the electrostatic latent image formed on the photosensitive drum 51. Thereby, the electrostatic latent image is visualized and a toner image is formed on the photosensitive drum 51. Thereafter, the toner image on the photosensitive drum 51 is transferred onto the sheet S by the sheet S being conveyed between the photosensitive drum 51 and the transfer roller 53.

[0043] The fixing device 6 is located behind the drum cartridge 5. The fixing device 6 includes a heating unit 61, a pressure roller 62, and a fixing device temperature sensor 63. The heating unit 61 includes a fixing heater 61A and a fixing belt 61B. The fixing heater 61A heats the fixing belt 61B. The pressure roller 62 sandwiches the fixing belt 61B between the nip plate of the heating unit 61. The pressure roller 62 forms a nip portion NP with the heating unit 61. In this fixing device 6, the toner image transferred onto the sheet S is fixed by heating the sheet S while the sheet S passes between the heating unit 61 and the pressure roller 62. The fixing device temperature sensor 63 is a sensor capable of detecting the temperature T of the fixing device 6.

[0044] The cutter unit 7 is located at the upper part of the apparatus main body 2. The cutter unit 7 is arranged downstream of the fixing device 6 in the conveyance direction of the sheet S. In the present embodiment, the cutter unit 7 is arranged in a second conveyance path 82 described later.

[0045] The cutter unit 7 has a cutter 75. The cutter unit 7 can cut the sheet S in the axial direction, that is, in a direction intersecting the conveyance direction, at the cutting position. In the present application, the cutting position is the position where the sheet S is cut by the cutter 75. The cutter unit 7 can cut at least a letter-sized sheet S and an A4-sized sheet S at the central position of the sheet in the conveyance direction. Note that the letter-sized sheet S is 215.9 mm × 279.4 mm. When the letter-sized sheet is cut in half, the dimension in the conveyance direction becomes 139.7 mm. Also, the A4-sized sheet S is 210 mm × 297 mm. When the A4-sized sheet is cut in half, the dimension in the conveyance direction becomes 148.5 mm.

[0046] As shown in FIGS. 2 and 3, the cutter unit 7 has a cutter frame 71, a slide rail 72, a fixed blade 73, a sheet passing portion 74, a cutter 75, a slide holder 76, a drive pulley 77, a pulley belt 78, a position sensor 79, and a cutting motor M1.

[0047] The cutter frame 71 extends in the axial direction. The slide rail 72 is a rail that extends axially and is formed on the cutter frame 71. The fixed blade 73 is a flat blade that extends axially and is fixed to the cutter frame 71. The sheet passing portion 74 is a space through which the sheet S passes and is formed in the cutter frame 71. In the present embodiment, the sheet passing portion 74 is formed between the slide rail 72 and the fixed blade 73.

[0048] The cutter 75 is a disc-shaped blade and is rotatably fixed to the slide holder 76. The cutter 75 is a moving blade that moves by the sliding movement of the slide holder 76. The cutter 75 is removable. Specifically, the cutter 75 is removable when it is in the initial position shown in FIG. 3. Thereby, when the moving blade is worn by cutting, it can be replaced with a new one.

[0049] The slide holder 76 engages with the slide rail 72 and is attached to the cutter frame 71 so as to be slidable along the slide rail 72. The slide holder 76 is movable from the initial position shown in FIG. 3 to the cutting completion position shown in FIG. 4. Before cutting the sheet S, the slide holder 76 is located in the initial position shown in FIG. 3. When the slide holder 76 moves along the slide rail 72 to the cutting completion position, one sheet S is sandwiched between the fixed blade 73 and the cutter 75 and cut into two sheets. The slide holder 76 is returned from the cutting completion position to the initial position before starting to cut the next sheet S.

[0050] The drive pulley 77 is disposed on the other axial side of the cutter frame 71. The drive pulley 77 can rotate forward and backward under the driving force of the cutting motor M1.

[0051] The pulley belt 78 is wound around the drive pulley 77. Further, a slide holder 76 is fixed to the pulley belt 78. Accordingly, the slide holder 76 is configured to slide axially in response to the rotation of the pulley belt 78. Specifically, when the cutting motor M1 rotates forward, the slide holder 76 slides axially from one side to the other side, and when the cutting motor M1 rotates reversely, the slide holder 76 slides axially from the other side to one side.

[0052] The position sensor 79 is a sensor that detects whether the cutter 75 is located at the initial position. The position sensor 79 is swingable between the swing position shown in FIG. 3 and the non-swing position shown in FIG. 4. The position sensor 79 is biased by a biasing member such as a spring (not shown) so as to be located at the non-swing position. As shown in FIG. 3, when the cutter 75 is located at the initial position, the position sensor 79 is pushed by the cutter 75 and is located at the swing position. When the cutter 75 is not located at the initial position, the position sensor 79 is not pushed by the cutter 75 and is located at the non-swing position.

[0053] In the cutter unit 7, when cutting the sheet S, the cutting motor M1 is rotated forward to move the slide holder 76 located at the initial position toward the cutting completion position. Then, since the cutter 75 moves together with the slide holder 76, the sheet S located at the sheet passing portion 74 is sandwiched between the fixed blade 73 and the cutter 75 and is cut. When the slide holder 76 reaches the cutting completion position, the cutting motor M1 stops. After the cut sheet S is discharged, the cutting motor M1 rotates reversely, and the slide holder 76 is returned from the cutting completion position to the initial position.

[0054] Returning to FIG. 1, the sheet conveying unit 8 includes a first conveying path 81, a second conveying path 82, a first discharge roller 84, a second discharge roller 85, a conveying roller 86, and a flapper 87.

[0055] The first conveyance path 81 is a path through which the sheet S that has passed through the fixing device 6 is discharged outside the apparatus main body 2 without passing through the cutting position. Specifically, the first conveyance path 81 is a path from the flapper 87 to the first discharge port 23. In the present embodiment, the first conveyance path 81 is passed through by the sheet S that has not been cut by the cutter unit 7.

[0056] The second conveyance path 82 is a path different from the first conveyance path 81. The second conveyance path 82 is a path through which the sheet S that has passed through the fixing device 6 is discharged outside the apparatus main body 2 after passing through the cutting position. Specifically, as shown by the two-dot chain line in FIG. 1, the second conveyance path 82 is a path from the flapper 87 to the second discharge port 24. In the present embodiment, the second conveyance path 82 is mainly a path through which the sheet cut by the cutter unit 7 passes. The second conveyance path 82 has a longer conveyance path than the first conveyance path 81.

[0057] The first discharge roller 84 is disposed on the first conveyance path 81 and is a roller that discharges the sheet S outside the apparatus main body 2. In the present embodiment, the first discharge roller 84 is a pair of rollers arranged in the vertical direction. The first discharge roller 84 is rotatable about an axis parallel to the axial direction. The first discharge roller 84 discharges the sheet S that has not been cut by the cutter unit 7 outside the apparatus main body 2. The first discharge roller 84 is located closer to the fixing device 6 than the second discharge roller 85.

[0058] The second discharge roller 85 is disposed on the second conveyance path 82 and is a roller that discharges the sheet S outside the apparatus main body 2. In the present embodiment, the second discharge roller 85 is a pair of rollers arranged in the vertical direction. The second discharge roller 85 is rotatable about the axial direction. The second discharge roller 85 mainly discharges the sheet S cut by the cutter unit 7 outside the apparatus main body 2. The second discharge roller 85 is located above the first discharge roller 84 and on the downstream side in the discharge direction of the sheet S. The second discharge roller 85 is rotatable by the drive of the conveyance motor M2 (see FIG. 7).

[0059] The conveying roller 86 is a roller that is disposed inside the apparatus main body 2 and conveys the sheet S. In the present embodiment, the conveying roller 86 is a roller that conveys the sheet S passing through the cutting position. The conveying roller 86 is disposed on the second conveying path 82. The conveying roller 86 is disposed downstream of the fixing device 6 in the conveying direction of the sheet S and is located between the flapper 87 and the cutter 75. In the present embodiment, the conveying roller 86 is a pair of rollers arranged in the vertical direction. The conveying roller 86 is rotatable by the driving of the conveying motor M2 (see FIG. 7).

[0060] The flapper 87 is located at the branching portion between the first conveying path 81 and the second conveying path 82. The flapper 87 is movable between a first position shown by a solid line in FIG. 1 and a second position shown by a two-dot chain line in FIG. 1. When the flapper 87 is located at the first position, it guides the sheet S that has passed through the fixing device 6 to the first conveying path 81. When the flapper 87 is located at the second position, it guides the sheet S that has passed through the fixing device 6 to the second conveying path 82.

[0061] As shown in FIG. 1, the operation panel PA is located on the outer surface of the apparatus main body 2. The operation panel PA enables the user to input commands such as an image formation command and a command to cut the sheet S.

[0062] The first sheet sensor SE1, the second sheet sensor SE2, the third sheet sensor SE3, and the fourth sheet sensor SE4 are sensors that are disposed on the conveying path of the sheet S and can detect the presence or absence of the sheet S.

[0063] The first sheet sensor SE1 is located between the separation roller 34 and the registration roller 35 in the conveying direction of the sheet S. The first sheet sensor SE1 is located immediately before the registration roller 35. The second sheet sensor SE2 is located between the registration roller 35 and the photoreceptor drum 51 in the conveying direction of the sheet. The third sheet sensor SE3 is located between the fixing device 6 and the flapper 87 in the conveying direction of the sheet.

[0064] The fourth sheet sensor SE4 is an example of a sensor that detects the sheet S. The fourth sheet sensor SE4 is located downstream in the conveyance direction from the conveyance roller 86. The fourth sheet sensor SE4 is located between the cutter 75 and the second discharge roller 85. The fourth sheet sensor SE4 is rotatably fixed to the apparatus main body 2.

[0065] The control unit CU includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and an input / output circuit, and executes control of the image forming apparatus 1 by performing various arithmetic processes based on programs and data stored in the ROM and the like.

[0066] As shown in FIG. 5, the control unit CU is electrically connected to the first sheet sensor SE1, the second sheet sensor SE2, the third sheet sensor SE3, the fourth sheet sensor SE4, the cartridge mounting sensor 5A, the toner remaining amount sensor 58, and the operation panel PA, and can receive respective detection signals and the like. The control unit CU controls the cutting motor M1, the conveyance motor M2, the polygon motor 42, and the flapper 87 based on information received from the operation panel PA and each sensor. In this embodiment, the conveyance motor M2 can be set to three speed levels: low speed, medium speed, and high speed.

[0067] When the control unit CU does not cut the sheet S by the cutter 75, the control unit CU positions the flapper 87 at the first position. Thereby, the sheet S is guided to the first conveyance path 81. The sheet S guided to the first conveyance path 81 is conveyed by the first discharge roller 84 and discharged from the first discharge port 23 to the discharge tray 22.

[0068] When the control unit CU cuts the sheet S with the cutter 75, it positions the flapper 87 at the second position. As a result, the sheet S is guided to the second conveyance path 82. The sheet S guided to the second conveyance path 82 is conveyed to the conveyance roller 86. That is, when cutting the sheet S, the control unit CU causes the conveyance roller 86 to convey the sheet S. The control unit CU stops the conveyance roller 86 while the sheet S is positioned at the cut position, and causes the cutter 75 to cut the sheet S while the conveyance roller 86 is stopped.

[0069] Here, as shown in FIG. 6, in the present embodiment, the control unit CU can execute a print-only mode, a print-and-cut mode, and a cut-only mode. FIG. 6 is a screen that the control unit CU displays on the operation panel PA when the user instructs the image forming apparatus to perform printing or copying. The user selects the print-only mode, the print-and-cut mode, and the cut-only mode via the screen of the operation panel PA together with instructions for printing or copying.

[0070] Also, when the control unit CU executes the cut-only mode, it can execute either the speed-priority mode or the accuracy-priority mode that has been selected. Hereinafter, the control of the control unit CU that executes after receiving a command (also referred to as a "job" in the following description) for executing each mode will be described. In the present embodiment, the control unit CU operates according to the mode selected via the operation panel PA.

[0071] When the control unit CU executes the print-only mode, it forms an image on the sheet S with the image forming unit and does not cut the sheet S. When the control unit CU executes the print-only mode, it executes "print preparation processing" after receiving a job.

[0072] When the control unit CU executes the print-and-cut mode, it forms an image on the sheet S with the image forming unit and cuts the sheet S with the cutter 75. When the control unit CU executes the print-only mode, it executes "print preparation processing" after receiving a job.

[0073] The time required for the printing preparation process is the "preparation operation time" in the printing-only mode and the printing and cutting mode. In the printing preparation process, when the control unit CU determines that the drum cartridge 5 is not installed in the apparatus main body 2, the execution of the printing and cutting mode is prohibited. When the control unit CU determines that the drum cartridge 5 is not installed in the apparatus main body 2, the control unit CU displays a cartridge not installed error on the operation panel PA.

[0074] Also, in the printing preparation process, when the control unit CU determines that the remaining amount of toner in the toner storage unit 57 is equal to or less than a predetermined amount, the execution of the printing and cutting mode is prohibited. When the control unit CU determines that the remaining amount of toner in the toner storage unit 57 is equal to or less than a predetermined amount, the control unit CU displays toner empty on the operation panel PA.

[0075] Also, in the printing preparation process, the control unit CU rotates the polygon motor 42 and starts supplying the sheet S from the supply tray 31 on the condition that the rotation of the polygon motor 42 has stabilized.

[0076] Also, in the printing preparation process, the control unit CU starts supplying the sheet S from the supply tray 31 on the condition that the temperature T of the fixing device 6 is equal to or higher than the first temperature T1. In the printing preparation process, the control unit CU turns on the fixing heater 61A after setting the target temperature of the fixing device 6 to T4. The target temperature T4 is the target temperature of the fixing device 6 when forming an image. The first temperature T1 is the temperature at which the supply of the sheet S is started when executing image formation, and is a temperature slightly lower than the target temperature T4. In the present embodiment, the target temperature T4 of the fixing device 6 is 200°C, and the first temperature T1 is 195°C.

[0077] When the control unit CU executes the printing and cutting mode, the control unit CU rotates the conveyance motor M2 at the first rotation speed R1 (medium speed).

[0078] When the control unit CU executes the cut-only mode, it cuts the sheet S with the cutter 75 without forming an image on the sheet S. Also, when the control unit CU executes the cut-only mode, even if it determines that the drum cartridge 5 is not mounted on the apparatus main body 2, it does not prohibit the execution of the cut-only mode. Further, when the control unit CU executes the cut-only mode, even if it determines that the remaining amount of toner in the toner storage unit 57 is equal to or less than a predetermined amount, it does not prohibit the execution of the cut-only mode. Also, when the control unit CU executes the cut-only mode, it starts supplying the sheet S from the supply tray 31 without rotating the polygon motor 42.

[0079] The control unit CU controls so that the time from receiving a command to execute the cut-only mode until discharging the sheet S to the discharge tray 22 is shorter than the time from receiving a command to execute the print-and-cut mode until discharging the sheet S to the discharge tray 22.

[0080] Therefore, when the control unit CU executes the cut-only mode, it increases the conveyance speed of the sheet S more than when executing the print-and-cut mode. Specifically, when the control unit CU executes the cut-only mode, it rotates the conveyance motor M2 at a second rotation speed R2 (high speed) faster than the first rotation speed R1 (medium speed) (R1 < R2).

[0081] Also, the control unit CU controls so that the preparation operation time from receiving a command to execute the cut-only mode until starting to convey the sheet S from the supply tray 31 is shorter than the preparation operation time from receiving a command to execute the print-and-cut mode until starting to convey the sheet S from the supply tray 31. Specifically, when the control unit CU executes the only-cut mode, it starts supplying the sheet S from the supply tray 31 on the condition that the fuser 6 is at a temperature equal to or higher than a second temperature T2 which is lower than the first temperature T1. If the temperature of the fuser 6 is too low, the sliding resistance due to the grease between the components inside the fuser 6 and the frictional resistance of the resin sleeve or ball bearing increase, so that the torque required to operate the fuser 6 is too large, etc., and the fuser 6 cannot be moved smoothly. The second temperature T2 is, for example, 115°C.

[0082] The control unit CU controls the temperature of the fuser 6 by controlling the energization of the fuser heater 61A. The control unit CU controls the temperature of the fuser 6 according to the temperature T detected by the fuser temperature sensor 63 and the target temperature. Specifically, when the control unit CU executes the only-cut mode, in order for the fuser 6 to reach the second temperature T2, the target temperature of the fuser 6 is set to T5. The target temperature T5 is the target temperature of the fuser 6 when the only-cut mode is executed, and is a temperature slightly higher than the second temperature T2. Also, in order to prevent the temperature of the fuser 6 from rising unnecessarily, the target temperature T5 is set to a temperature lower than the target temperature T4 during fixing and the first temperature T1 which is the supply start temperature of the sheet S. For example, the target temperature T5 is 120°C.

[0083] Here, as described above, when the control unit CU executes the only-cut mode, it executes either the speed-priority mode or the accuracy-priority mode that has been selected. When the speed-priority mode is selected, the control unit CU executes the "speed-priority cutting preparation process" after receiving the job. When the accuracy-priority mode is selected, the control unit CU executes the "accuracy-priority cutting preparation process" after receiving the job. The time required for the "speed-priority cutting preparation process" is the "preparation operation time" in the speed-priority mode. The time required for the "accuracy-priority cutting preparation process" is the "preparation operation time" in the accuracy-priority mode. In the only-cut mode, since the target temperature of the fuser 6 is lower than that in the only-print mode and the print-cut mode, the preparation operation time in the only-cut mode is often shorter than the preparation operation time in the only-print mode and the print-cut mode.

[0084] The accuracy-priority cutting preparation process is a mode that prioritizes the dimensional accuracy of the sheet S to be cut. When the control unit CU executes the accuracy-priority mode, it starts supplying the sheet S from the supply tray 31 on the condition that the temperature of the fuser 6 is equal to or higher than the second temperature T2 and lower than the first temperature T1 and equal to or lower than the third temperature T3. When the temperature of the fuser 6 is high, errors are likely to occur in the position of the sheet S when it is conveyed to the cutting position due to factors such as the sheet S shrinking due to heat or the conveyance roller 86 expanding. The third temperature T3 is a temperature lower than the target temperature T4 during fixing and the first temperature T1 which is the sheet supply start temperature, and is higher than the target temperature T5. The third temperature T3 is, for example, 150°C. Also, in the present embodiment, when executing the accuracy-priority mode, the conveyance motor M2 is rotated at a third rotation speed R3 (low speed) which is equal to or lower than the first rotation speed R1.

[0085] The speed-priority cutting preparation process is a mode that prioritizes the speed until the sheet S is discharged. When the control unit CU executes the speed-priority mode, if the temperature T of the fuser 6 is equal to or higher than the second temperature T2, it starts supplying the sheet S from the supply tray 31 even if the temperature is higher than the third temperature T3. Different from the accuracy-priority cutting preparation process, the speed-priority cutting preparation process does not wait for the temperature to drop even when the temperature of the fuser 6 is higher than the third temperature T3, and thus may be completed in a shorter time than the accuracy-priority cutting preparation process.

[0086] Next, an example of the operation executed by the control unit CU after receiving a job will be described with reference to the flowcharts of FIGS. 7 to 11.

[0087] As shown in FIG. 7, when the control unit CU determines that there is a job (S1, Yes), it determines whether another job is being executed (S2).

[0088] In step S2, when the control unit CU determines that another job is being executed (S2, Yes), it determines whether the received job is in the cut-only mode (S3).

[0089] In step S3, when the control unit CU determines that the received job is in the cut-only mode (S3, Yes), as shown in FIG. 8, the target temperature of the fixing device 6 is set to T5 (S10), and it is determined whether it is in the speed-priority mode (S11).

[0090] In step S11, when the control unit CU determines that it is in the speed-priority mode (S11, Yes), after waiting until the execution of another job is completed, the conveyance motor M2 is set to high speed (S12), the sheet S is cut without forming an image (S15), and the process ends. At this time, the control unit CU cuts the sheet S regardless of whether the temperature T of the fixing device 6 is higher than T5. In step S12, if the other job being executed is in the "cut-only mode" and "speed-priority mode", since the conveyance motor M2 is already at high speed, the control unit CU may omit step S12.

[0091] In step S11, when the control unit CU determines that it is not in the speed-priority mode (S11, No), since it is in the accuracy-priority mode, after waiting until the execution of another job is completed, the conveyance motor M2 is set to low speed (S13), and it waits until the temperature T of the fixing device 6 becomes equal to or lower than the third temperature T3 (S14). The control unit CU may stop the polygon motor 42 while waiting until the temperature T of the fixing device 6 becomes equal to the third temperature T3. In step S13, if the other job being executed is in the "cut-only mode" and "accuracy-priority mode", since the conveyance motor M2 is already at low speed, the control unit CU may omit step S13.

[0092] In step S14, when the control unit CU determines that the temperature T of the fixing device 6 has become equal to or lower than the third temperature (S14, Yes), the sheet S is cut without forming an image (S15), and the process ends.

[0093] Returning to FIG. 7, in step S3, when the control unit CU does not determine that the received job is in the cut-only mode (S3, No), since the received job includes image formation, the control unit CU executes print preparation processing (S20). After executing the print preparation processing, the control unit CU proceeds to step S6. In step S6, the control unit CU determines whether there is sheet cutting in the received job (S6).

[0094] As shown in FIG. 9, in the print preparation processing (S20), the control unit CU determines whether the drum cartridge 5 is mounted on the apparatus main body 2 (S21). Whether the drum cartridge 5 is mounted on the apparatus main body 2 or not is detected by a cartridge mounting sensor 5A (see FIG. 1).

[0095] In step S21, when the control unit CU does not determine that the drum cartridge 5 is mounted on the apparatus main body 2 (S22, No), since image formation cannot be performed, the control unit CU displays a cartridge not mounted error on the operation panel PA (S22) and ends the processing.

[0096] In step S21, when the control unit CU determines that the drum cartridge 5 is mounted on the apparatus main body 2 (S22, Yes), the control unit CU determines whether the toner remaining amount in the toner storage unit 57 is equal to or less than a predetermined amount (S23). Whether the toner remaining amount is equal to or less than a predetermined amount or not is detected by a toner remaining amount sensor 58 (see FIG. 1).

[0097] In step S23, when the control unit CU determines that the toner remaining amount is equal to or less than a predetermined amount (S23, Yes), since image formation cannot be performed due to toner shortage, the control unit CU displays toner empty on the operation panel PA (S24) and ends the processing.

[0098] In step S23, when the control unit CU does not determine that the toner remaining amount is equal to or less than a predetermined amount (S23, No), the control unit CU sets the target temperature of the fixing unit 6 to T4 (S25) and turns on the fixing heater 61A (S26).

[0099] After step S26, the control unit CU waits until the temperature T of the fixing device 6 becomes equal to or higher than the first temperature T1. When it is determined that the temperature has become equal to or higher than the first temperature T1 (S27, Yes), the transport motor M2 is turned on at medium speed and the polygon motor 42 is turned on (S28).

[0100] After step S28, the control unit CU waits until the operations of the transport motor M2 and the polygon motor 42 become stable. When it is determined that they have become stable (S29, Yes), the printing preparation process is terminated.

[0101] In step S6, when the control unit CU determines that there is no sheet cutting (S6, No), it performs image formation (S7) and ends the process. In step S6, when the control unit CU determines that there is sheet cutting (S6, Yes), it performs image formation (S8), cuts the sheet S (S9), and ends the process.

[0102] In step S2, when the control unit CU determines that another job is being executed (S2, No), it determines whether the received job is in the cut-only mode (S4).

[0103] In step S4, when the control unit CU determines that the received job is not in the cut-only mode (S4, No), since the received job includes image formation, it executes the printing preparation process (S20). After the control unit CU executes the printing preparation process, it proceeds to step S6.

[0104] In step S4, when the control unit CU determines that the received job is in the cut-only mode (S4, Yes), it determines whether it is in the speed-priority mode (S5).

[0105] In step S5, when the control unit CU determines that it is in the speed-priority mode (S5, Yes), it executes the speed-priority cut preparation process (S30) and proceeds to step S9.

[0106] As shown in FIG. 10, in the speed-priority cutting preparation process (S30), the control unit CU sets the target temperature of the fixing device 6 to T5 (S31), turns on the fixing heater 61A, and waits until the temperature of the fixing device 6 reaches the second temperature T2. When it is determined that the temperature is equal to or higher than the second temperature T2 (S33, Yes), the conveyance motor M2 is turned on at high speed (S34).

[0107] After step S34, the control unit CU waits until the operation of the conveyance motor M2 stabilizes. When it is determined that the operation has stabilized (S35, Yes), the speed-priority cutting preparation process ends. After the control unit CU ends the speed-priority cutting preparation process (S30), the supply of the sheet S from the supply tray 31 is started, and the sheet S is cut without forming an image on the sheet S (S9). Thus, when executing the speed-priority cutting preparation process, the control unit CU does not execute the process of determining whether the drum cartridge 5 is installed or the process of determining whether the toner remaining amount is equal to or less than a predetermined amount, unlike when executing the printing preparation process.

[0108] In step S5, when the control unit CU determines that it is not in the speed-priority mode (S5, No), it executes the accuracy-priority cutting preparation process (S40) and proceeds to step S9.

[0109] As shown in FIG. 11, in the accuracy-priority cutting preparation process (S40), the control unit CU sets the target temperature of the fixing device 6 to T5 (S41), waits until the temperature T of the fixing device 6 becomes equal to or lower than the third temperature T3, and when it is determined that the temperature is equal to or lower than the third temperature T3 (S42, Yes), turns on the fixing heater 61A (S43).

[0110] After step S43, it waits until the temperature T of the fixing device 6 becomes equal to or higher than the second temperature T2. When the temperature becomes equal to or higher than the second temperature T2 (S44, Yes), the conveyance motor M2 is turned on at low speed (S45).

[0111] After step S45, the control unit CU waits until the operation of the conveyance motor M2 stabilizes. When it determines that the operation has stabilized (S46, Yes), it ends the accuracy-priority cutting preparation process. After the control unit CU ends the accuracy-priority cutting preparation process (S40), it starts supplying the sheet S from the supply tray 31 and cuts the sheet S without forming an image on the sheet S (S9). In this way, when executing the speed-priority cutting preparation process, unlike when executing the printing preparation process, the control unit CU does not execute the process of determining whether the drum cartridge 5 is installed or the process of determining whether the toner remaining amount is less than a predetermined amount.

[0112] According to the above, the following effects can be obtained in the present embodiment. The image forming apparatus 1 in the present embodiment includes a cutter 75 capable of cutting the sheet S. And the control unit CU can execute a print cutting mode and a cut-only mode. When the control unit CU executes the cut-only mode, it cuts the sheet with the cutter 75 without forming an image on the sheet S. Therefore, in the image forming apparatus 1 including the image forming unit and the cutter 75, it is possible to execute only cutting without forming an image on the sheet S.

[0113] Also, when the control unit CU executes the cut-only mode, even if it determines that the drum cartridge 5 is not installed in the apparatus main body 2, it does not prohibit the execution of the cut-only mode. Further, when the control unit CU executes the cut-only mode, even if it determines that the remaining amount of toner in the toner storage unit 57 is less than a predetermined amount, it does not prohibit the execution of the cut-only mode. In this way, when the control unit CU executes the cut-only mode, in order to control the preparation operation time to be shorter compared to when executing the print cutting mode, it can start operating earlier compared to when executing the print cutting mode.

[0114] Also, when the control unit CU executes the cut-only mode, the supply of the sheet S is started on the condition that the fixing device 6 is at a temperature equal to or higher than a second temperature T2 (e.g., 115°C) which is lower than the first temperature T1 (e.g., 195°C). Therefore, when the cut-only mode is executed, the operation can be started earlier than when the print cut mode is executed.

[0115] Also, when the control unit CU executes the accuracy priority mode, in order to cut the sheet after the temperature T of the fixing device 6 becomes equal to or lower than the third temperature T3, it is possible to suppress the deviation of the stop position of the sheet S due to the expansion of the conveyance roller 86. For this reason, the sheet S can be cut accurately. Also, when the speed priority mode is executed, since the sheet S is cut even when the temperature of the fixing device 6 is higher than the third temperature T3, there is no need to wait for the time for the fixing device 6 to cool down, so the operation can be started earlier.

[0116] Also, when the control unit CU executes the cut-only mode, since the polygon motor 42 is not rotated, the supply of the sheet S is started without waiting for the rotation of the polygon motor 42 to stabilize. For this reason, the operation can be started earlier.

[0117] Also, when the control unit CU executes the cut-only mode, since the conveyance motor M2 is made faster than when the print cut mode is executed, the operation can be started earlier.

[0118] Also, when the control unit CU executes the speed priority mode, since the conveyance motor M2 is made faster than when the accuracy priority mode is executed, the operation can be completed earlier. When the accuracy priority mode is executed, since the conveyance motor M2 is made slower than when the accuracy priority mode is executed, the sheet can be cut accurately.

[0119] Even when the control unit CU determines that no cartridge is attached to the apparatus main body 2, since execution of the cut-only mode is not prohibited, the cut-only mode can be executed even when the drum cartridge 5 is not attached to the apparatus main body 2.

[0120] Also, even when the control unit CU determines that the remaining amount of toner in the toner storage unit 57 is equal to or less than a predetermined amount, since execution of the cut-only mode is not prohibited, the cut-only mode can be executed even when the remaining amount of toner is equal to or less than the predetermined amount.

[0121] Further, when the control unit CU executes the cut-only mode, it controls so that the time from receiving a command until discharging a sheet to the discharge tray becomes shorter than when executing the print cut mode. Therefore, when executing the cut-only mode, the operation can be completed earlier compared to when executing the print cut mode.

[0122] As described above, the embodiments of the present disclosure have been described. However, the present disclosure is not limited to the above embodiments. Regarding the specific configuration, appropriate changes can be made without departing from the spirit of the present disclosure.

[0123] In the above-described embodiment, the configuration does not have a pressure contact and separation mechanism for pressing and separating the developing roller 55 against and from the photosensitive drum 51. However, the image forming unit may have a pressure contact and separation mechanism. The pressure contact and separation mechanism can press and separate the developing roller 55 against and from the photosensitive drum 51. For example, when the control unit CU executes the print cut mode, since it executes image formation, it presses the developing roller 55 against the photosensitive drum 51. Then, when the control unit CU executes the cut-only mode, since it does not execute image formation, it separates the developing roller 55 from the photosensitive drum 51. According to this configuration, when executing the cut-only mode, since the developing roller 55 is separated from the photosensitive drum 51, deterioration of the photosensitive drum 51 and the developing roller 55 can be suppressed.

[0124] In the above-described embodiment, when the control unit CU executes the printing and cutting mode, the conveyance motor M2 is rotated at the first rotation speed R1 (medium speed), and when executing the cutting-only mode and the speed priority mode, it is rotated at the second rotation speed R2 (high speed), and when executing the cutting-only mode and the accuracy priority mode, it is rotated at the third rotation speed R3 (low speed). However, the first rotation speed R1 and the second rotation speed R2 may be the same rotation speed, or the second rotation speed R2 and the third rotation speed R3 may be the same rotation speed.

[0125] In the above-described embodiment, the case where the image forming apparatus 1 cuts a sheet S of letter size or A4 size is exemplified, but the present invention is also applicable to the case of cutting sheets S of other sizes. For example, the present invention may be applied to the case of cutting a sheet S smaller than letter size or A4 size, such as postcard size or A5 size, or to the case of cutting a sheet S of B4 size or A3 size.

[0126] In the above-described embodiment, the sheets S discharged from the first discharge port 23 and the second discharge port 24 were both placed on one discharge tray 22, but they may be accommodated in separate trays.

[0127] In the above-described embodiment, the sheets S discharged from the first discharge port 23 and the second discharge port 24 were both placed on the discharge tray 22, but it may be configured without a discharge tray. Although illustration is omitted, for example, the sheets S discharged from the first discharge port 23 and the second discharge port 24 may be directly discharged onto a desk or the floor, and the sheets S may be placed on the desk or the floor.

[0128] In the above-described embodiment, the control unit CU executed processing according to the mode selected via the operation panel PA. However, for example, via the print driver of a PC that sends a print instruction to the image forming apparatus, the user may select one of the print-only mode, the print and cut mode, and the cut-only mode. In that case, a job including the selected mode is sent from the PC to the image forming apparatus, and the control unit CU executes the mode specified in the job.

[0129] In the above-described embodiment, the first discharge roller 84, the second discharge roller 85, and the conveyance roller 86 each consisted of a pair of rollers made up of two rollers. However, the present invention is not limited to this, and each may be composed of one roller or may be composed of three or more rollers.

[0130] In the above-described embodiment, the image forming unit was of the laser printer type. However, the image forming unit may be of the electrophotographic type or the inkjet type.

[0131] In the above-described embodiment, the image forming apparatus was a laser printer that forms monochrome images. However, the present invention is not limited to this. For example, the image forming apparatus may be a printer that forms color images. Further, the image forming apparatus is not limited to a printer. For example, the image forming apparatus may be a copier, a multifunction device, or the like.

[0132] In the above-described embodiment, while the control unit CU was configured to receive the next job during the execution of another job and, when the received job was in the cut-only mode (FIG. 7: S3, Yes), execute the processes of steps S10 to 15 (see FIG. 8), the control unit CU may wait until the job being executed ends and then execute the received job. In this case, since the control unit CU waits in step S2 until another job being executed ends when the job is received, it proceeds to step S4 without proceeding to step S3 (see FIG. 7).

[0133] Each element described in the above-described embodiment and modification example may be implemented by arbitrarily combining them.

Explanation of Reference Numerals

[0134] 1 Image forming apparatus 2 Apparatus main body 5 Drum cartridge 6 Fuser 7 Cutter unit 31 Feeding tray 40 Deflector 41 Polygon mirror 42 Polygon Motor 51 Photoconductor Drum 55 Developing Roller 75 Cutter 86 Conveyor Roller CU Control Unit M1 Cutting Motor M2 Conveyor Motor

Claims

1. A device main body, an image forming unit disposed within the device main body for forming an image on a sheet, a cutter disposed downstream of the image forming unit in the sheet conveyance direction and capable of cutting the sheet in an intersection direction intersecting the conveyance direction, a discharge tray from which the sheet is discharged, and a control unit, wherein the control unit determines which of a printing and cutting mode for forming an image on a sheet and then cutting the sheet and a cutting-only mode for cutting the sheet without forming an image on the sheet is selected, and is capable of executing the determined mode, when executing the printing and cutting mode, forms an image on the sheet with the image forming unit and cuts the sheet with the cutter, and when executing the cutting-only mode, cuts the sheet with the cutter without forming an image on the sheet. An image forming apparatus characterized by the above.

2. further comprising a supply tray for accommodating sheets, wherein the control unit controls such that a preparation operation time from receiving a command to execute the cutting-only mode until starting to convey a sheet from the supply tray is shorter than a preparation operation time from receiving a command to execute the printing and cutting mode until starting to convey a sheet from the supply tray. The image forming apparatus according to Claim 1.

3. further comprising a supply tray for accommodating sheets, wherein the image forming unit further has a fixing device for fixing a toner image on a sheet by heating the sheet on which the toner image has been transferred, and the control unit when executing the printing and cutting mode, starts supplying a sheet from the supply tray on condition that the fixing device is at a first temperature or higher, and when executing the cutting-only mode, starts supplying a sheet from the supply tray on condition that the fixing device is at a second temperature or higher, which is lower than the first temperature. The image forming apparatus according to Claim 1.

4. the control unit when executing the cutting-only mode, is capable of executing either a speed-priority mode that prioritizes the speed until sheet discharge or an accuracy-priority mode that prioritizes the dimensional accuracy of the sheet to be cut, and when executing the accuracy-priority mode, starts supplying a sheet from the supply tray on condition that the temperature of the fixing device is at a third temperature or lower, which is higher than the second temperature and lower than the first temperature. When executing the speed priority mode, if the temperature of the fixing device is equal to or higher than the second temperature, even if it is higher than the third temperature, the image forming apparatus according to claim 3, wherein feeding of the sheet from the supply tray is started.

5. Further comprising a supply tray for accommodating sheets, The image forming unit, A photosensitive drum, A deflector having a polygon mirror that deflects a beam emitted from a light source, and a polygon motor that rotates the polygon mirror, the deflector being configured to emit the beam deflected by the polygon mirror to the photosensitive drum. The control unit, When executing the printing and cutting mode, the polygon motor is rotated, and feeding of the sheet from the supply tray is started on the condition that the rotation of the polygon motor has stabilized. The image forming apparatus according to claim 1, wherein when executing the cutting only mode, feeding of the sheet from the supply tray is started without rotating the polygon motor.

6. Further comprising a conveyance roller disposed in the apparatus main body for conveying the sheet, and a conveyance motor for rotating the conveyance roller. The control unit, When executing the printing and cutting mode, the conveyance motor is rotated at a first rotation speed. The image forming apparatus according to claim 1, wherein when executing the cutting only mode, the conveyance motor is rotated at a second rotation speed higher than the first rotation speed.

7. The control unit, When executing the cutting only mode, a speed priority mode that prioritizes the speed until the sheet is discharged and an accuracy priority mode that prioritizes the dimensional accuracy of the sheet to be cut can be executed. When executing the speed priority mode, the conveyance motor is rotated at the second rotation speed. The image forming apparatus according to claim 6, wherein when executing the accuracy priority mode, the conveyance motor is rotated at a third rotation speed that is equal to or lower than the first rotation speed.

8. The image forming unit includes a photosensitive drum, a developing roller that supplies toner to the photosensitive drum, and a pressure contact and separation mechanism that can pressure contact and separate the developing roller with respect to the photosensitive drum. The control unit, When executing the printing and cutting mode, the developing roller is pressure contacted with the photosensitive drum. The image forming apparatus according to claim 1, wherein when executing the cutting only mode, the developing roller is separated from the photosensitive drum.

9. The image forming unit is detachable from the apparatus main body and has a cartridge capable of accommodating consumables for image formation therein, when the control unit determines that no cartridge is attached to the apparatus main body, execution of the printing and cutting mode is prohibited, The image forming apparatus according to any one of claims 1 to 8, characterized in that execution of only the cutting mode is not prohibited.

10. The image forming unit has a storage unit in which consumables for image formation are stored, when the control unit determines that the remaining amount of the consumables in the storage unit is equal to or less than a predetermined amount, execution of the printing and cutting mode is prohibited, The image forming apparatus according to any one of claims 1 to 8, characterized in that execution of only the cutting mode is not prohibited.

11. The control unit controls such that the time from receiving a command to execute only the cutting mode until a sheet is discharged onto the discharge tray is shorter than the time from receiving a command to execute the printing and cutting mode until a sheet is discharged onto the discharge tray. The image forming apparatus according to claim 1.

Images