Image forming apparatus

Abstract

To shorten a harness that connects a solenoid actuator moving a movable chute and a control board controlling the solenoid actuator to each other.SOLUTION: An image forming apparatus comprises: a main body housing 2; a transfer roller that rotates about a rotation axis extending in a first direction; a movable chute 120; a solenoid actuator 150; and a control board B1. The solenoid actuator 150 moves the movable chute 120 between a first position and a second position. The main body housing 2 has a first frame F arranged on one side in the first direction with respect to the movable chute 120, and a second frame F2 arranged on the other side in the first direction. The control board B1 is arranged on the first frame F1. The solenoid actuator 150 is located closer to the first frame F1 than the second frame F2 in the first direction.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus equipped with a movable chute. [Background technology]

[0002] There is known an image forming apparatus equipped with a movable chute that guides a sheet to a fixing unit (see Patent Document 1). In this image forming apparatus, the movable chute is moved to prevent wrinkles from occurring on the sheet when it enters the fixing unit. The movable chute is operated by a solenoid actuator. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-091631 A Summary of the Invention [Problem to be solved by the invention]

[0004] If the harness connecting the control board that controls the operation of the movable chute and the solenoid actuator that moves the movable chute is long, the noise that the harness receives inside the main body housing and the noise that the harness generates will increase. In addition, a long harness increases the wiring cost. For this reason, it is desirable to shorten the harness connecting the control board and the solenoid actuator.

[0005] In view of the above, an object of the present disclosure is to provide an image forming apparatus capable of shortening the harness connecting the solenoid actuator that moves the movable chute and the control board that controls the solenoid actuator. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, an image forming apparatus according to the present disclosure includes a main body housing, a transfer roller, a fixing unit, a movable chute, a solenoid actuator, and a control board. The transfer roller rotates about a rotation axis extending in a first direction. The transfer roller transfers a toner image to a sheet. The fixing unit fixes the toner image transferred to the sheet to the sheet. The movable chute is located between the transfer roller and the fixing unit in the sheet conveying direction. The movable chute guides the sheet. The movable chute is movable between a first position and a second position located below the first position. The solenoid actuator moves the movable chute. The control board has a control unit that controls at least the solenoid actuator. The main body housing has a first frame and a second frame. The first frame is disposed on one side of the movable chute in a first direction. The first frame supports a solenoid actuator. The second frame is disposed on the other side of the main body housing in the first direction with respect to the movable chute. The control board is disposed on the first frame. The solenoid actuator is located closer to the first frame than to the second frame in the first direction.

[0007] By positioning the solenoid actuator close to the first frame where the control board is located, the harness connecting the control board and the solenoid actuator can be shortened, which reduces noise inside the main body housing and also cuts wiring costs.

[0008] The image forming apparatus may further include a harness connecting the control board and the solenoid actuator. The control board may have a mounting surface on which a first connector to which the harness is connected is mounted. The mounting surface may face in a direction away from the movable chute in the first direction and be located farther from the movable chute than the solenoid actuator.

[0009] Since the mounting surface of the control board faces away from the movable chute, noise generated by the solenoid actuator can be prevented from reaching the mounting surface of the control board.

[0010] Also, the present invention may include a wireless board having a board for wireless communication, the wireless board being directly connected to the control board. The wireless board may be disposed on the opposite side of the solenoid actuator in the first direction across the first frame, and the solenoid actuator may overlap with the wireless board via the first frame when viewed from the first direction.

[0011] By positioning the first frame between the solenoid actuator and the wireless board, noise from the solenoid actuator can be prevented from reaching the wireless board.

[0012] In addition, in the first direction, the control board may be located between the movable chute and the wireless board.

[0013] Also, the upper end of the wireless board may be located above the upper end of the solenoid actuator.

[0014] Since the upper end of the wireless board is located above the upper end of the solenoid actuator, the wireless board is less susceptible to the effects of noise from the solenoid actuator, improving the communication stability of the wireless board.

[0015] The image forming apparatus may further include a second board disposed on the second frame, and a cable electrically connecting the control board and the second board. The movable chute may be rotatable between a first position and a second position about a rotation axis extending in the first direction. The cable may pass under the movable chute at a position between the rotation axis of the movable chute and the lowest point of the movable chute located at the second position in the sheet conveying direction.

[0016] The cable that electrically connects the control board and the second board passes under the movable chute, so the cable is less likely to interfere with the movable chute.

[0017] Moreover, the solenoid actuator may have a main body portion and a movable portion, and the movable portion may be movable between a third position and a fourth position moved from the third position in the first direction.

[0018] The device may also be provided with a link mechanism that positions the movable chute at the first position when the movable part is in the third position, and positions the movable chute at the second position when the movable part is in the fourth position.

[0019] The link mechanism may also have a first link, a second link, and a third link. In this case, the first link may have one end connected to the movable part and be movable in the first direction. The second link may be connected to the other end of the first link and be rotatable about the first axis by movement of the first link. The third link may be connected to the second link and be movable between a pressing position where the movable chute is pressed down to the second position and an allowing position where the movable chute is allowed to be located at the first position by rotation of the second link.

[0020] Since the link mechanism has the first link, the second link, and the third link, the link mechanism can make the amount of movement of the movable chute greater than the amount of movement of the solenoid actuator, thereby making it possible to prevent the solenoid actuator from becoming large.

[0021] The control unit may position the movable chute at the first position for each sheet on which an image is formed before the leading end of the sheet reaches the fixing unit, and the control unit may move the movable chute from the first position to the second position for each sheet on which an image is formed after the leading end of the sheet reaches the fixing unit.

[0022] The control unit moves the movable chute from the first position to the second position for each sheet on which an image is formed, thereby making it possible to prevent wrinkles from occurring on the sheet. Effect of the Invention

[0023] According to the present invention, it is possible to shorten the harness connecting the solenoid actuator that moves the movable chute and the control board that controls the solenoid actuator. [Brief description of the drawings]

[0024] [Figure 1] 1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment. [Diagram 2] 1 is a view of the vicinity of the movable chute located at a first position as viewed from a first direction. [Diagram 3] 1 is a view of the vicinity of the movable chute located at a second position as viewed from a first direction. [Figure 4] FIG. [Diagram 5] FIG. 2 is a perspective view showing the positions of the first frame, the second frame, the exhaust fan, and the duct. [Figure 6] FIG. 2 is a top view showing the positions of the first frame, the second frame, the exhaust fan and the duct. [Figure 7] FIG. [Figure 8] FIG. 2 is a perspective view of a first frame. [Figure 9] FIG. 4 is a front view of the first frame. [Figure 10] FIG. 2 is a perspective view of a link mechanism and a solenoid actuator. [Figure 11] 13 is a diagram showing the link mechanism when the movable chute is located at a first position. FIG. [Figure 12] 13 is a diagram showing the link mechanism when the movable chute is located at a second position. FIG. [Figure 13] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. 1, the image forming apparatus 1 is a laser printer that forms an image on a sheet S. The image forming apparatus 1 includes a main body housing 2, a supply unit 3, a process unit 4, a fixing unit 6, and a discharge unit 7. In the following description, the direction in which the rotation axis X1 of the photosensitive drum 51, which will be described later, extends is referred to as the "first direction." Also, the transport direction of the sheet S from the process unit 4 toward the fixing device 6 is referred to as the "second direction." The first direction intersects with the second direction. In this embodiment, the first direction is perpendicular to the second direction. Also, the arrows indicating each direction in the drawings indicate "one side" in each direction.

[0026] The supply section 3 includes a supply tray 31 and a sheet supply device 32. The supply tray 31 is a tray that stores sheets S. The sheet supply device 32 transports the sheets S in the supply tray 31 toward the process section 4.

[0027] The process unit 4 forms a toner image on the supplied sheet S. The process unit 4 includes an exposure device 40 and a process cartridge 50.

[0028] The exposure device 40 is provided in the upper part of the main body housing 2, and has a laser emission unit (not shown), a rotatably driven polygon mirror 41, a lens 42, and a reflecting mirror 44. A laser beam (see dashed line) based on image data emitted from the laser emission unit is reflected or passes through the polygon mirror 41, the lens 42, and the reflecting mirror 44 in this order, and is scanned at high speed on the surface of the photosensitive drum 51.

[0029] The process cartridge 50 is disposed below the exposure device 40. The process cartridge 50 is configured to be replaceable by being attached to and detached from the main body housing 2 through an opening formed when a front cover 23 provided on the main body housing 2 is opened. The process cartridge 50 has a photosensitive drum 51, a charger 52, a transfer roller 53, a developing roller 54, a supply roller 55, a toner storage section 56, and a toner memory 57.

[0030] The photosensitive drum 51 rotates about a rotation axis X1 extending in a first direction.

[0031] The transfer roller 53 rotates about a rotation axis X4 extending in the first direction. The transfer roller 53 forms a transfer nip NP1 between itself and the photosensitive drum 51. The transfer roller 53 transfers the toner image on the photosensitive drum 51 onto the sheet S. The toner memory 57 is a memory in which information about the process cartridge 50 is stored.

[0032] The fixing unit 6 thermally fixes the toner image transferred to the sheet S. The fixing unit 6 is provided downstream in the conveying direction of the process unit 4. The fixing unit 6 has a heating rotor 61, a pressure rotor 62, and a fixing frame 63.

[0033] The heating rotator 61 is a member that heats the sheet S. The heating rotator 61 is an endless belt. The heating rotator 61 houses a heater inside, and heats the sheet S by rotating with the sheet S sandwiched between the heating rotator 61 and the pressure rotator 62.

[0034] The pressure rotating body 62 is a member that forms a fixing nip NP2 between itself and the heating rotating body 61. The pressure rotating body 62 is a roller whose surface is made of a non-conductive elastic body. The heating rotating body 61 and the pressure rotating body 62 are pressed against each other by a pressing member (not shown).

[0035] The fixing frame 63 is a frame that covers the heating rotor 61 and the pressure rotor 62. The fixing frame 63 supports the heating rotor 61 and the pressure rotor 62 so that they can rotate.

[0036] In the process unit 4, the surface of the photosensitive drum 51 is uniformly charged to a positive polarity by the charger 52, and then exposed to high-speed scanning of a laser beam from the exposure device 40, thereby forming an electrostatic latent image on the photosensitive drum 51. The toner in the toner storage unit 56 is supplied to the development roller 54 via the supply roller 55 and carried on the development roller 54.

[0037] Then, the toner carried on the developing roller 54 is supplied to the electrostatic latent image on the photosensitive drum 51, whereby the electrostatic latent image is made visible and a toner image is formed on the photosensitive drum 51. Thereafter, the sheet S supplied from the supply unit 3 is transported between the photosensitive drum 51 and the transfer roller 53 (transfer nip NP1), and a negative transfer bias is applied to the transfer roller 53, whereby the toner image on the photosensitive drum 51 is transferred onto the sheet S. Next, the sheet S is transported between the heating rotator 61 and the pressure rotator 62 (fixing nip NP2), whereby the toner image transferred onto the sheet S is thermally fixed.

[0038] The discharge section 7 conveys the sheet S on which the toner image has been thermally fixed toward the outside of the main body housing 2. The discharge section 7 has discharge rollers 73. The discharge rollers 73 discharge the sheet S onto the discharge tray 22.

[0039] The image forming apparatus 1 has a re-conveying mechanism 9. The re-conveying mechanism 9 is a mechanism that re-conveys the sheet S to the process unit 4 in a state in which the sheet S is turned over after an image has been formed on a first side of the sheet S, in order to form an image on a second side of the sheet S. In FIG. 1, the re-conveyed sheet S is indicated by a two-dot chain line.

[0040] The re-conveying mechanism 9 includes a flapper 91 and a plurality of re-conveying rollers 92, 93, and 94. The flapper 91 is rotatable between an initial position indicated by a solid line and a re-conveying position indicated by a two-dot chain line. When the flapper 91 is located at the initial position, the sheet S discharged from the fixing unit 6 is guided toward the discharge tray 22. When the flapper 91 is located at the re-conveying position, the sheet S discharged from the fixing unit 6 is guided toward the re-conveying path by the discharge rollers 73 rotating in reverse at a predetermined timing.

[0041] The image forming apparatus 1 further includes a guide member 100. The guide member 100 is located below the process cartridge 50, and guides the sheet S from the transfer nip NP1 toward the fixing nip NP2. The guide member 100 also guides the sheet S on the re-conveying path toward the transfer nip NP1. The re-conveying path is formed below the guide member 100. As shown in FIG. 2, the guide member 100 has a base portion 110, a movable chute 120, and a spring 130. The movable chute 120 is movable between a first position shown in FIG. 2 and a second position shown in FIG. 3.

[0042] The base portion 110 has a first recess 111, a second recess 112, and a bottom surface 113. The first recess 111 is located at the end of the top surface of the base portion 110 on the other side in the second direction. The first recess 111 is a portion into which a part of the transfer roller 53 fits. The second recess 112 is located at the end of the top surface of the base portion 110 on one side in the second direction. The second recess 112 is a portion that rotatably supports the movable chute 120. The bottom surface 113 is the lower surface of the base portion 110, and is a guide surface that guides the sheet S on the re-conveying path.

[0043] The movable chute 120 is located between the photosensitive drum 51 and the fixing unit 6 in the sheet transport direction. The movable chute 120 guides the sheet S. The movable chute 120 is rotatable between a first position shown in FIG. 2 and a second position shown in FIG. 3. The second position is located below the first position. The movable chute 120 is rotatable between the first position and the second position about a rotation axis X2 extending in the first direction.

[0044] As shown in FIG. 4, the movable chute 120 has a base portion 121, a plurality of guide ribs 122, a cylindrical portion 123, a pressed portion 124, and a stopper 125.

[0045] The base portion 121 has a plate shape that is curved downward and concave. The base portion 121 extends in a first direction and a second direction.

[0046] The guide ribs 122 are ribs that protrude upward from the base portion 121, and extend in the second direction along the curve of the base portion 121. The guide ribs 122 form a conveying surface that conveys the sheet S of the movable chute 120.

[0047] Cylindrical portion 123 is disposed at the other end in the second direction of base portion 121. Cylindrical portions 123 are disposed at both ends in the first direction of movable chute 120, one at each end. Cylindrical portion 123 is a portion that axially supports movable chute 120.

[0048] Pressed portion 124 is disposed at one end of movable chute 120 in the first direction and at one end in the second direction. Pressed portion 124 protrudes upward from base portion 121. Pressed portion 124 is a portion that is pressed by link mechanism 200, which will be described later, when movable chute 120 moves from the first position to the second position.

[0049] Stopper 125 comes into contact with duct DU, which will be described later, to restrict the movement of movable chute 120. Stopper 125 is located between cylindrical portion 123 and pressed portion 124 in the second direction. Stopper 125 is located at both ends of movable chute 120 in the first direction.

[0050] The spring 130 is a torsion spring. The spring 130 is disposed at both ends of the movable chute 120 in the first direction. The spring 130 has a coil portion 131, a first arm 132, and a second arm 133. The coil portion 131 is engaged with the outside of the cylindrical portion 123. The first arm 132 extends from the coil portion 131 and is hooked on the base portion 110. The second arm 133 extends from the coil portion 131 and is hooked on the movable chute 120. The spring 130 always biases the movable chute 120 upward. As a result, when the movable chute 120 is not pressed by the link mechanism 200, the movable chute 120 is pushed upward by the spring 130, and the stopper 125 comes into contact with the duct DU and is located at the first position.

[0051] As shown in FIG. 5, the main body housing 2 has a first frame F1, a second frame F2, a third frame F3, and a fourth frame F4.

[0052] The first frame F1 is a wall located on one side in the first direction of the main body housing 2. The first frame F1 is disposed on one side of the movable chute 120 in the first direction.

[0053] The second frame F2 is a wall located on the other side in the first direction of the main body housing 2. The second frame F2 is disposed on the other side in the first direction with respect to the movable chute 120.

[0054] The third frame F3 has a flat plate shape and extends in the first direction. The third frame F3 connects the first frame F1 and the second frame F2. The exposure device 40 is fixed to the upper surface of the third frame F3. The third frame F3 has a flange F31 that extends upward from one end in the second direction.

[0055] The fourth frame F4 has a flat plate shape and extends in the first direction. The fourth frame F4 connects the lower end of the first frame F1 and the lower end of the second frame F2.

[0056] As shown in Figures 5 and 6, the image forming apparatus 1 further includes an exhaust fan FA, a duct DU, a control board B1, a second board B2, a cable CB, a wireless board B3, a first harness H1, a second harness H2, a third harness H3, a thermistor TH, an electrical contact CT, a solenoid actuator 150, and a link mechanism 200.

[0057] The exhaust fan FA is disposed on the second frame F2. The exhaust fan FA is disposed substantially in the center of the second frame F2 in the second direction. The exhaust fan FA is capable of discharging air inside the main body housing 2 to the outside of the main body housing 2.

[0058] The duct DU is a member that guides the air in the main body housing 2 to the exhaust fan FA in order to exhaust the air in the main body housing 2 to the outside of the main body housing 2. Specifically, the duct DU guides the air in the main body housing 2 from one side to the other side in the first direction. The duct DU extends in the first direction from the first frame F1 to the second frame F2. The duct DU overlaps with the movable chute 120 when viewed from the top-bottom direction (see also FIG. 1). A solenoid actuator 150 is disposed at one end of the duct DU in the first direction. An exhaust fan FA is disposed at the other end of the duct DU in the first direction. That is, the duct DU is located between the exhaust fan FA and the solenoid actuator 150. The duct DU is located on one side of the exposure device 40 in the second direction. The duct DU is fixed to a flange F31 of the third frame F3 with a screw N (see also FIG. 2).

[0059] As shown in Fig. 7, the duct DU has a first wall DU1, a second wall DU2, a third wall DU3, a plurality of connecting ribs DU4, and an opening DU5. The first wall DU1, the second wall DU2, the third wall DU3, and the plurality of connecting ribs DU4 form a flow path for air to flow in a first direction. In other words, the flow path of the duct DU is a space surrounded by the first wall DU1, the second wall DU2, the third wall DU3, and the plurality of connecting ribs DU4.

[0060] The first wall DU1 is a wall perpendicular to the second direction and extends in the first direction. The first wall DU1 has a first protrusion DU11, a second protrusion DU12, and a fixing hole DU13. The first protrusion DU11 and the second protrusion DU12 are used to fix a link mechanism 200, which will be described later. The fixing hole DU13 is a hole through which a screw N passes to fix the duct DU to the third frame F3 (see FIG. 2).

[0061] The second wall DU2 is a wall perpendicular to the second direction and extends in the first direction. The second wall DU2 faces the first wall DU1.

[0062] The third wall DU3 connects one end of the first wall DU1 in the first direction to one end of the second wall DU2 in the first direction. The third wall DU3 is a wall perpendicular to the first direction. The third wall DU3 has a protruding portion DU31 protruding to the other side in the first direction. A groove DU32 extending in the up-down direction is formed on the peripheral surface of the protruding portion DU31 (see FIG. 13).

[0063] The multiple connecting ribs DU4 are ribs that connect the lower end of the first wall DU1 and the lower end of the second wall DU2. Each connecting rib DU4 is a wall perpendicular to the first direction and extends in the second direction. A multiple number of holes DU8 that penetrate vertically are formed between each connecting rib DU4. Air heated inside the main body housing 2 enters the flow path of the duct DU from the holes DU8 between each connecting rib DU4.

[0064] The opening DU5 is an opening formed on the other side in the first direction. The opening DU5 is located opposite the exhaust fan FA. When the exhaust fan FA operates, the air that has entered the duct DU is exhausted from the opening DU5.

[0065] As shown in Fig. 8, the control board B1 is a board having a control unit CU. The control board B1 is disposed in the first frame F1. The control board B1 is located at one end of the first frame F1 in the second direction. The control board B1 has a mounting surface B11 on which electrical components are mounted.

[0066] The mounting surface B11 faces one side in the first direction, which is the outside of the main body housing 2. That is, the mounting surface B11 faces a direction away from the movable chute 120 in the first direction (see FIG. 6). In the first direction, the mounting surface B11 is located farther away from the movable chute 120 than the solenoid actuator 150 is. In addition to the control unit CU, the first connector CN1, the second connector CN2, and the wireless board B3 are mounted on the mounting surface B11.

[0067] A first harness H1 that passes electricity is connected to the first connector CN1 and is connected to the solenoid actuator 150. The first harness H1 is an example of a harness, and connects the control board B1 and the solenoid actuator 150. The first harness H1 extends upward from the first connector CN1, and then is wired to the other side of the wireless board B3 in the first direction so as to bypass the wireless board B3 (see FIG. 9). The socket of the first harness H1 in the first connector CN1 faces one side in the first direction, which is the outside of the main body housing 2.

[0068] The second connector CN2 is connected to the second harness H2 and the third harness H3. The second harness H2 connects the control board B1 and the thermistor TH. The third harness H3 connects the control board B1 and the electrical contacts CT. The second harness H2 and the third harness H3 extend upward from the second connector CN2, and are then wired to the other side of the wireless board B3 in the first direction, bypassing the wireless board B3 (see FIG. 9). The sockets of the second harness H2 and the third harness H3 in the second connector CN2 face one side in the first direction, which is the outside of the main body housing 2.

[0069] The control unit CU includes a CPU, a RAM, a ROM, an input / output circuit, etc., and executes control by performing various arithmetic processing based on programs and data stored in the ROM, etc. In this embodiment, the control unit CU controls the solenoid actuator 150. Specifically, the control unit CU positions the movable chute 120 at a first position before the leading end of the sheet S reaches the fixing device 6 every time an image is formed on one sheet S. Then, the control unit CU moves the movable chute 120 from the first position shown in FIG. 2 to the second position shown in FIG. 3 after the leading end of the sheet S reaches the fixing device 6 every time an image is formed on one sheet S.

[0070] The wireless board B3 is a board for wireless communication. The wireless board B3 is directly connected to the control board B1. That is, the wireless board B3 is directly connected to the control board B1 without a harness or the like.

[0071] As shown in Figs. 5 and 6, the second substrate B2 is disposed in the second frame F2. The second substrate B2 has an AC-DC conversion circuit (not shown). The AC-DC conversion circuit is a circuit that converts an AC voltage input from a commercial power source into a predetermined DC voltage. As an example, the AC-DC conversion circuit converts AC 100V into DC 24V. The control substrate B1 and the second substrate B2 are connected by a cable CB. The converted DC voltage is sent from the second substrate B2 to the control substrate B1 via the cable CB.

[0072] The cable CB is a cable that electrically connects the control board B1 and the second board B2. As shown in Fig. 4, the cable CB passes under the movable chute 120. As shown in Fig. 3, the cable CB passes through a position between the rotation axis X2 of the movable chute 120 and the lowest point BP of the movable chute 120 located at the second position in the conveying direction of the sheet S.

[0073] As shown in FIG. 6, the control board B1 is located between the movable chute 120 and the wireless board B3 in the first direction. As shown in FIG. 9, the wireless board B3 is disposed on the opposite side of the solenoid actuator 150 with the first frame F1 in between. When viewed from the first direction, the solenoid actuator 150 at least partially overlaps with the wireless board B3 via the first frame F1. In addition, the upper end of the wireless board B3 is located above the upper end of the solenoid actuator 150. In the up-down direction, the upper end of the wireless board B3 is located between the upper end of the control board B1 and the upper end of the solenoid actuator 150.

[0074] 8, the thermistor TH is disposed on the outer surface of the first frame F1. The thermistor TH is disposed at the other end of the first frame F1 in the second direction. The thermistor TH detects the temperature outside the device.

[0075] The electrical contacts CT are disposed on the top of the first frame F1. The electrical contacts CT are disposed on the other end of the first frame F1 in the second direction. The electrical contacts CT are in electrical contact with the toner memory 57. The control unit CU reads information from the toner memory 57 via the electrical contacts CT.

[0076] As shown in FIG. 6, the solenoid actuator 150 is disposed on the first frame F1 and supported by the first frame F1. The solenoid actuator 150 is located closer to the first frame F1 than the second frame F2 in the first direction. As shown in FIG. 2, the solenoid actuator 150 overlaps with the flow path of the duct DU as viewed from the first direction. Also, the solenoid actuator 150 overlaps with the exhaust fan FA as viewed from the first direction. As shown in FIG. 6, the solenoid actuator 150 has a main body portion 151 and a movable portion 152. The solenoid actuator 150 moves the movable chute 120 between a first position shown in FIG. 2 and a second position shown in FIG. 3.

[0077] As shown in FIG. 10, the main body 151 has a rectangular parallelepiped shape. The movable part 152 is a pin that is movable relative to the main body 151 and is slidable in the first direction. The movable part 152 is movable between a third position and a fourth position. When the ON signal is not sent from the control unit CU, the movable part 152 is located at the third position. When the ON signal is sent from the control unit CU, the movable part 152 is pulled and moves from the third position to the fourth position on the other side of the first direction. When the ON signal is no longer sent from the control unit CU, the movable part 152 is not pulled to the fourth position and returns to the third position. When the movable part 152 is located at the third position, the movable chute 120 is located at the first position. Also, when the solenoid actuator 150 is located at the fourth position, the movable chute 120 is located at the second position.

[0078] 2, when viewed from the first direction, the movable part 152 entirely overlaps with the exhaust fan FA. In other words, the projection of the movable part 152 in the first direction entirely overlaps with the arrangement area of ​​the exhaust fan FA.

[0079] 11 and 12, the tip of the movable part 152 is located inside the duct DU both when it is located at the third position and when it is located at the fourth position. That is, a part of the movable part 152 overlaps with the flow path of the duct DU when viewed from the second direction.

[0080] 10, the link mechanism 200 is a mechanism that positions the movable chute 120 at the first position when the movable part 152 is located at the third position, and positions the movable chute 120 at the second position when the solenoid actuator 150 is located at the fourth position. A part of the link mechanism 200 is located inside the duct DU (see FIG. 5). The link mechanism 200 has a first link 210, a second link 220, a third link 230, a holder 240, and a coil spring 250.

[0081] The holder 240 holds a part of the link mechanism 200. The holder 240 is supported by the duct DU in a state in which the holder 240 holds the link mechanism 200. Specifically, the holder 240 is engaged with and fixed to a first protrusion DU11 and a second protrusion DU12 of the duct DU (see FIG. 7). The holder 240 has a base portion 241, an extension portion 242, a first hook 243, a boss 244, and a contact portion 245.

[0082] The base portion 241 extends in a first direction. The extension portion 242 extends upward and to one side in the first direction from one end of the base portion 241 in the first direction. The extension portion 242 covers a part of the upper side of the main body portion 151 of the solenoid actuator 150. As shown in FIG. 11, the extension portion 242 has an engagement claw 242A that protrudes downward from the extension portion 242. The engagement claw 242A engages with the upper surface of the main body portion 151 of the solenoid actuator 150. As a result, the holder 240 is positioned in the first direction with respect to the solenoid actuator 150.

[0083] 10, the first hook 243 is located at the other end in the first direction of the base portion 241. The first hook 243 is engaged with one end of the coil spring 250.

[0084] The boss 244 is disposed at an end portion on the other side in the first direction of the base portion 241. The boss 244 is a cylindrical projection that protrudes from the base portion 241 to one side in the second direction. The boss 244 supports the second link 220 so that the second link 220 is rotatable.

[0085] The contact portion 245 is disposed between the extension portion 242 and the boss 244 in the first direction. The contact portion 245 is a protrusion that protrudes from the base portion 241 to one side in the second direction. The contact portion 245 has a first contact surface 241A and a second contact surface 241B. A sponge is attached to the surface of each of the first contact surface 241A and the second contact surface 241B. Each sponge is configured to be crushed to a predetermined thickness when pressed by the first link 210 or the second link 220.

[0086] The first contact surface 241A faces the other side in the first direction. The first contact surface 241A is an example of a contact surface that comes into contact with the first link 210 when the movable part 152 moves from the third position to the fourth position.

[0087] The second contact surface 241B faces downward. The second contact surface 241B is a surface that comes into contact with the second link 220 when the movable part 152 moves from the fourth position to the third position.

[0088] The first link 210 is a member that is connected to the solenoid actuator 150 and slides in the first direction together with the solenoid actuator 150 when the solenoid actuator 150 moves in the first direction. The first link 210 extends in the first direction. The first link 210 has a base portion 211, a first hole 213, and a first protrusion 214.

[0089] The base portion 211 has a square rod shape extending in the first direction. One end of the base portion 211 on one side in the first direction is connected to the tip of the movable portion 152 of the solenoid actuator 150. As a result, when the solenoid actuator 150 moves in the first direction, the first link 210 also moves in the first direction in conjunction with the movement.

[0090] The first hole 213 is disposed at the other end in the first direction of the base portion 211. The first hole 213 is a rectangular hole that penetrates in the up-down direction.

[0091] The first protrusion 214 extends downward from one end of the base portion 211 in the first direction. The first protrusion 214 is located on one side in the first direction from the center of the base portion 211 in the first direction. The first protrusion 214 is a portion that abuts against the first abutment surface 241A of the holder 240 when the movable portion 152 moves from the third position to the fourth position.

[0092] The second link 220 is a member that is connected to the first link 210 and rotates about the first axis X3 as the rotation center when the first link 210 moves in the first direction. The second link 220 is located below the first link 210. The second link 220 has a base portion 221, a cylindrical portion 222, a second protruding portion 223, a third protruding portion 224, a second hook 225, and a third abutting surface 226.

[0093] The base portion 221 has a square rod shape extending in the first direction. The cylindrical portion 222 is disposed at the other end of the base portion 221 in the first direction. The cylindrical portion 222 is formed in a cylindrical shape. The boss 244 of the holder 240 fits inside the cylindrical portion 222. When the boss 244 fits into the cylindrical portion 222, the second link 220 becomes rotatable about the first axis X3.

[0094] The second protrusion 223 protrudes upward from the outer circumferential surface of the cylindrical portion 222. The second protrusion 223 fits into the first hole 213 of the first link 210. As a result, the second link 220 is connected to the other end of the first link 210 and is rotatable about the first axis X3 by the movement of the first link 210. Specifically, when the first link 210 moves to one side in the first direction, the first link 210 presses the second protrusion 223 to one side in the first direction, so that the second link 220 rotates clockwise in FIG. 10.

[0095] The third protruding portion 224 protrudes to one side in the first direction from one end in the first direction of the base portion 221. The third protruding portion 224 is connected to the third link 230.

[0096] Second hook 225 protrudes upward from the outer circumferential surface of cylindrical portion 222. Second hook 225 is located on the other side in the first direction than second protruding portion 223. Second hook 225 is engaged with the other end of coil spring 250.

[0097] The third contact surface 226 is a surface located on the upper side of one end of the base portion 221 in the first direction. The third contact surface 226 comes into contact with the second contact surface 241B when the second link 220 rotates counterclockwise in FIG. 10 and rises. The third contact surface 226 comes into contact with the second contact surface 241B, so that the second link 220 does not rotate any further.

[0098] The third link 230 is connected to the second link 220, and is a member that slides up and down in response to the up and down movement of the third protrusion 224 of the second link 220 when the second link 220 rotates. Specifically, the third link 230 is connected to the second link 220. The third link 230 can move between a pressing position and an allowable position by the rotation of the second link 220. The pressing position is a position where the third link 230 presses the movable chute 120 down to the second position. The allowable position is a position where the third link 230 does not press the movable chute 120 down and allows the movable chute 120 to be located at the first position. The third link 230 extends in the up and down direction and is located below the second link 220. The third link 230 has a base portion 231, a third hole 232, and a chute pressing portion 233.

[0099] The base portion 231 has a rectangular rod shape extending in the vertical direction. As shown in FIG. 13, the base portion 231 has a base hole 231H and a rail 231R. The base hole 231H is a rectangular hole formed inside the base portion 231. The base hole 231H is a hole that extends in the vertical direction and penetrates in the first direction. The rail 231R extends in the vertical direction and is formed on the inner walls on both sides of the base hole 231H. The rail 231R engages with a groove D32 formed in the protruding portion DU31 of the duct DU. The rail 231R engages with the groove D32, allowing the third link 230 to slide in the vertical direction.

[0100] The third hole 232 is a rectangular hole located at the upper end of the third link 230. The third protrusion 224 of the second link 220 fits into the third hole 232. As a result, when the second link 220 rotates, the third link 230 slides up and down.

[0101] Chute pressing portion 233 is a portion that presses movable chute 120 downward. Chute pressing portion 233 is located at the lower end of third link 230. When third link 230 moves downward, chute pressing portion 233 comes into contact with pressed portion 124 of movable chute 120 to press movable chute 120 downward. In this manner, when moving movable chute 120 from the first position to the second position, third link 230 presses movable chute 120 from the conveying surface side.

[0102] The coil spring 250 is a tension spring, and constantly pulls the second link 220 to the other side in the first direction.

[0103] As shown in FIG. 11, when the ON signal is not sent from the control unit CU, the movable unit 152 is located at the third position. When the ON signal is sent from the control unit CU, the movable unit 152 is pulled and moves from the third position to the fourth position. As shown in FIG. 12, when the movable unit 152 moves from the third position to the fourth position, the first link 210 slides to one side in the first direction together with the movable unit 152. When the first link 210 slides to one side in the first direction, the second protrusion 223 of the second link 220 is moved to one side in the first direction by the first link 210. When the second protrusion 223 moves to one side in the first direction, the second link 220 rotates clockwise in FIG. 12. When the second link 220 rotates clockwise, the third protrusion 224 pushes the third link 230 downward. When the third link 230 is pressed downward, the third link 230 moves to the pressing position, and the chute pressing portion 233 presses downward the pressed portion 124 of the movable chute 120. This causes the movable chute 120 to move from the first position to the second position.

[0104] On the other hand, when the ON signal is no longer sent from the control unit CU, the movable part 152 is not pulled to the fourth position, and the first link 210 does not press the second link 220. Therefore, the second link 220 rotates counterclockwise from the state shown in FIG. 12 due to the biasing force of the coil spring 250. When the second link 220 rotates counterclockwise, the third link 230 is pulled upward by the third protrusion 224 of the second link 220, as shown in FIG. 11. When the third hole 232 is pulled upward, the third link 230 moves from the pressing position to the allowable position, and the chute pressing part 233 does not press the pressed part 124 of the movable chute 120. When the third link 230 moves to the allowable position, the movable chute 120 moves from the second position to the first position due to the biasing force of the spring 130. Furthermore, when the second link 220 rotates counterclockwise, the first link 210 is pulled to the other side in the first direction by the second protrusion 223 of the second link 220. When the first link 210 is pulled to the other side in the first direction, the movable part 152 is pulled to the other side in the first direction together with the first link 210, and returns to the third position.

[0105] According to the image forming apparatus 1 of this embodiment as described above, the following effects can be obtained. The image forming apparatus 1 includes a solenoid actuator 150 that moves the movable chute 120 up and down. In this embodiment, the control unit CU positions the movable chute 120 at a first position and a second position each time an image is formed on one sheet S. At this time, the control unit CU positions the movable chute 120 at the first position before the leading end of the sheet S reaches the fixing unit 6, and moves the movable chute 120 from the first position shown in FIG. 2 to the second position shown in FIG. 3 after the leading end of the sheet S reaches the fixing unit 6. By positioning the movable chute 120 at the first position before the leading end of the sheet S reaches the fixing device 6, the sheet S can enter the fixing nip NP2 at an ideal angle with respect to the fixing nip NP2. This makes it difficult for wrinkles to occur in the sheet S when it enters the fixing nip NP2. Moreover, the movable chute 120 is located at the second position with the sheet S nipped between the transfer nip NP1 and the fixing nip NP2. As a result, even if the sheet S becomes loose between the transfer nip NP1 and the fixing nip NP2 because the conveying speed of the sheet S in the transfer nip NP1 is faster than the conveying speed of the sheet S in the fixing nip NP2, the sheet S can be conveyed with the looseness of the sheet S absorbed. In detail, the movable chute 120 moves from the first position to the second position, so that the movable chute 120 can convey the sheet S while supporting it from below with the space between the transfer nip NP1 and the fixing nip NP2 expanded downward. Therefore, even if the sheet S becomes loose downward, it is possible to prevent the sheet S from changing its posture during conveyance or hitting other components in the main body housing 2. As a result, it is possible to prevent the toner image before fixing from being disturbed or the sheet S from becoming jammed.

[0106] Here, if the movable chute 120 is moved frequently, the solenoid actuator 150 may generate heat. When the solenoid actuator 150 generates heat, the performance may be degraded, for example, the suction force per unit of power may be reduced, compared to when the solenoid actuator 150 does not generate heat. Therefore, the solenoid actuator 150 needs to be cooled efficiently. In this embodiment, the solenoid actuator 150 overlaps with the exhaust fan FA when viewed from the first direction, so that the air around the solenoid actuator 150 can be efficiently circulated as shown by the air flow indicated by the arrows in FIG. 11. Therefore, the solenoid actuator 150 can be efficiently cooled compared to when the solenoid actuator 150 does not overlap with the exhaust fan FA when viewed from the first direction. As a result, the movable chute 120 can be operated frequently and continuously.

[0107] Furthermore, when viewed from the first direction, the solenoid actuator 150 overlaps with the flow path of the duct DU. Therefore, the air heated by the solenoid actuator 150 is guided by the duct DU to the exhaust fan FA in the shortest distance, so that the solenoid actuator 150 can be efficiently cooled.

[0108] Furthermore, when viewed from the first direction, the movable part 152 of the solenoid actuator 150 entirely overlaps with the exhaust fan FA, so that the movable part 152 can be cooled efficiently.

[0109] In addition, since the duct DU extends from the first frame F1 to the second frame F2, the duct DU can guide the heated air generated by the solenoid actuator 150 to the exhaust fan FA. Therefore, the solenoid actuator 150 can be efficiently cooled.

[0110] In addition, a part of the link mechanism 200 is located inside the duct DU. Therefore, it is not necessary to secure a separate space for arranging the link mechanism 200, and it is possible to prevent the image forming apparatus 1 from becoming large.

[0111] Furthermore, link mechanism 200 has first link 210, second link 220, and third link 230. Therefore, link mechanism 200 can make the amount of movement of movable chute 120 greater than the amount of movement of solenoid actuator 150. This makes it possible to prevent solenoid actuator 150 from becoming larger. By preventing solenoid actuator 150 from becoming larger, power consumption is reduced and heat generation can also be suppressed.

[0112] Furthermore, when the movable part 152 moves from the third position to the fourth position, the first link 210 comes into contact with the first contact surface 241A of the holder 240. Therefore, when the movable part 152 is located at the fourth position, the first link 210 is positioned by the first contact surface 241A. As a result, when the movable part 152 is located at the fourth position, the positional accuracy of the first link 210 can be maintained high.

[0113] Further, sponge is attached to the surface of each of the first contact surface 241A and the second contact surface 241B. This makes it possible to suppress the generation of abnormal noise when the first contact surface 241A contacts the first link 210 and when the second contact surface 241B contacts the second link 220. Each sponge is crushed to a predetermined thickness when pressed by the first link 210 or the second link 220, making it possible to suppress variation in the position of the movable chute located at the second position.

[0114] In addition, the solenoid actuator 150 is supported by the first frame F1 on which the control board B1 is arranged, and is located near the first frame F1. This allows the path of the first harness H1 connecting the control board B1 and the solenoid actuator 150 to be shortened. By shortening the first harness H1, the first harness H1 is prevented from receiving noise from the surroundings, and the first harness H1 is prevented from transmitting noise to the surroundings. In addition, the wiring cost can be reduced.

[0115] Furthermore, since the mounting surface B11 of the control board B1 faces in a direction away from the movable chute 120, noise generated in the solenoid actuator 150 can be prevented from reaching the mounting surface B11 of the control board B1.

[0116] In addition, the first frame F1 is located between the solenoid actuator 150 and the wireless board B3. Therefore, noise generated from the solenoid actuator 150 can be prevented from reaching the wireless board B3.

[0117] In addition, since the upper end of the wireless board B3 is located above the upper end of the solenoid actuator 150, the wireless board B3 is less susceptible to noise from the solenoid actuator 150, improving communication stability of the wireless board B3. The communication partner of the wireless board B3 is, for example, a mobile communication terminal carried by the user. Generally, a user carries a mobile communication terminal at a position higher than the image forming apparatus 1, so that the solenoid actuator 150 is not disposed above the wireless board B3 between the wireless board B3 and the mobile communication terminal, and thus the wireless board B3 is less susceptible to noise from the solenoid actuator 150.

[0118] In addition, since the cable CB that electrically connects the control board B1 and the second board B2 passes under the movable chute 120, the cable CB is unlikely to interfere with the movable chute 120. Furthermore, since the cable CB passes under the movable chute 120 at a position between the rotation axis X2 of the movable chute 120 and the lowest point BP of the movable chute 120 located at the second position in the conveying direction of the sheet S, the cable CB can be routed at a position where the amount of vertical movement of the movable chute 120 is small, and the cable CB is less likely to interfere with the movable chute 120.

[0119] In addition, link mechanism 200 for moving movable chute 120 has first link 210, second link 220, and third link 230. Therefore, the amount of movement of movable chute 120 can be made larger than the amount of movement of solenoid actuator 150. As a result, the size of solenoid actuator 150 can be prevented from increasing. By preventing solenoid actuator 150 from increasing in size, power consumption and heat generation can be reduced.

[0120] Furthermore, the control unit CU moves the movable chute 120 from the first position to the second position every time an image is formed on one sheet S. This makes it possible to prevent wrinkles from occurring on the sheet S.

[0121] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. The specific configuration can be appropriately changed without departing from the spirit of the present invention.

[0122] In the embodiment described above, the image forming apparatus 1 has a transfer roller 53 facing the photosensitive drum 51 that transfers the toner on the photosensitive drum 51 to the sheet S. However, the image forming apparatus 1 may also be configured so that the toner on the photosensitive drum 51 is transferred to an intermediate transfer belt, and the toner on the intermediate transfer belt is transferred to the sheet S by a transfer roller or a secondary transfer roller.

[0123] In the above-described embodiment, the movable chute 120 was capable of rotating between the first position and the second position around the rotation axis X2 extending in the first direction, but the movable chute 120 may also be configured to move between the first position and the second position by sliding movement.

[0124] In the above embodiment, the image forming apparatus 1 is a monochrome laser printer, but the image forming apparatus may be a color image forming apparatus, a copier, or a multifunction machine. The image forming apparatus 1 may be an LED type printer in which the exposure device 40 has a plurality of LEDs, and the plurality of LEDs blink based on image data to expose the surface of the photosensitive drum 51. The sheet is not limited to paper, and may be an overhead projector sheet or the like. Furthermore, the heating rotator is not limited to one using an endless belt, but may also use a roller, and the pressure rotator is not limited to one using a roller, but may also use an endless belt.

[0125] Furthermore, the elements of each of the above-described embodiments can be implemented in any combination. [Explanation of symbols]

[0126] 1. Image forming device 2 Main unit 6 Fixing unit 40 Exposure equipment 51 Photosensitive drum 53 Transfer roller 100 Guide member 110 Base 120 Movable Chute 130 Spring 150 Solenoid Actuator 151 Main body 152 Moving parts 200 Link mechanism 210 First Link 220 Second Link 230 Third Link B1 Control Board B2 Second board B3 Radio Board DU Duct FA Exhaust Fan

Claims

1. A main body housing; a transfer roller that rotates about a rotation axis extending in a first direction and transfers the toner image onto a sheet; a fixing device that fixes the toner image transferred onto the sheet onto the sheet; a movable chute that is located between the transfer roller and the fixing unit in a sheet conveying direction and guides a sheet, the movable chute being movable between a first position and a second position that is located below the first position; a solenoid actuator for moving the movable chute; A control board having a control unit that controls at least the solenoid actuator, the main body housing has a first frame disposed on one side of the movable chute in the first direction and supporting the solenoid actuator, and a second frame disposed on the other side of the main body housing in the first direction with respect to the movable chute, the control board is disposed on the first frame, The image forming apparatus, wherein the solenoid actuator is located closer to the first frame than the second frame in the first direction.

2. a harness connecting the control board and the solenoid actuator; the control board has a mounting surface on which a first connector to which the harness is connected is mounted, The mounting surface, in the first direction, facing away from the movable chute; 2. The image forming apparatus according to claim 1, wherein the solenoid actuator is positioned farther from the movable chute than the solenoid actuator.

3. A wireless board having a board for wireless communication, the wireless board being directly connected to the control board; the wireless board is disposed on an opposite side of the solenoid actuator with the first frame therebetween in the first direction, 3. The image forming apparatus according to claim 2, wherein the solenoid actuator overlaps with the wireless board via the first frame when viewed from the first direction.

4. 4. The image forming apparatus according to claim 3, wherein the control circuit board is located between the movable chute and the wireless circuit board in the first direction.

5. 4. The image forming apparatus according to claim 3, wherein an upper end of the wireless circuit board is located above an upper end of the solenoid actuator.

6. a second board disposed on the second frame; and a cable electrically connecting the control board and the second board, the movable chute is rotatable between the first position and the second position about a rotation axis extending in the first direction; 2. The image forming apparatus according to claim 1, wherein the cable passes under the movable chute at a position between the rotation axis of the movable chute and the lowest point of the movable chute located at the second position in the sheet transport direction.

7. The solenoid actuator has a main body and a movable part, 2 . The image forming apparatus according to claim 1 , wherein the movable portion is movable between a third position and a fourth position moved from the third position in the first direction.

8. 8. The image forming apparatus according to claim 7, further comprising a link mechanism that positions the movable chute at a first position when the movable portion is located at a third position, and positions the movable chute at a second position when the movable portion is located at a fourth position.

9. The link mechanism includes: a first link having one end connected to the movable portion and movable in the first direction; a second link connected to the other end of the first link and rotatable about a first axis by movement of the first link; 9. The image forming apparatus according to claim 8, further comprising: a third link connected to the second link and movable between a pressing position in which the movable chute is pressed down to the second position and an allowing position in which the movable chute is allowed to be located at the first position when the second link rotates.

10. The control unit, for each sheet on which an image is formed, before the leading end of the sheet reaches the fixing device, the movable chute is positioned at the first position; 2. The image forming apparatus according to claim 1, wherein the movable chute is moved from the first position to the second position after the leading end of the sheet reaches the fixing unit.

Images