Image forming apparatus

Abstract

In an image forming apparatus comprising a connecting substrate having a connector and a member having a shape for exposing the connector, the connector is exposed without using an opening as the shape for exposing the connector. [Solution] The image forming apparatus has an image forming section including an image carrier and a housing that houses the image forming section. The housing has an outer casing, a first side plate having a first surface intersecting the rotation axis direction of the image carrier, a second side plate having a second surface intersecting the rotation axis direction, wherein the second surface faces the first surface in the rotation axis direction, and a stay connected to the first side plate and the second side plate. A connecting substrate supported by the stay has a connector exposed to the outside of the housing and a wiring board to which the connector is attached. When viewed in the rotation axis direction, the connector overlaps with a recess formed on the outer edge of the first side plate and also overlaps with the second side plate.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus that forms an image on a recording material.

Background Art

[0002] Some image forming apparatuses for printing an image on a recording material have a connection board including a connector for connecting to an external device such as a computer.

[0003] The image forming apparatus described in Patent Document 1 includes a board having a connector and a controller box for housing the board. The controller box is provided with an opening for exposing the connector, and a user can insert a storage medium, a cable, etc. into the connector.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When an image forming apparatus includes a connection board having a connector and a member having an opening (hole) for exposing the connector, it is necessary to ensure sufficient rigidity for the portion around the opening to withstand loads such as external forces.

[0006] One object of the present invention is to expose the connector without using an opening as the shape for exposing the connector when the image forming apparatus includes a connection board having a connector and a member having a shape for exposing the connector.

Means for Solving the Problems

[0007] One invention according to the present application is as follows.

[0008] In an image forming apparatus that forms an image on a recording material, An image forming unit including an image carrier, A housing for the image forming unit, Exterior parts and A first side plate having a first surface that intersects the rotation axis direction of the image carrier, A second side plate having a second surface that intersects the rotation axis direction, wherein the second surface of the second side plate faces the first surface in the rotation axis direction, A stay connected to the first side plate and the second side plate, A housing having the image forming unit positioned between the first side plate and the second side plate in the direction of the rotation axis, A connecting board supported by the stay, comprising a connector exposed to the outside of the housing and a wiring board to which the connector is attached, It has, When viewed in the direction of the rotation axis, the connector overlaps with the recess formed on the outer edge of the first side plate and also overlaps with the second side plate. An image forming apparatus characterized by the following: [Effects of the Invention]

[0009] As described above, according to the present invention, when an image forming apparatus comprises a connecting substrate having a connector and a member having a shape for exposing the connector, the connector can be exposed without using an opening as the shape for exposing the connector. [Brief explanation of the drawing]

[0010] [Figure 1] This diagram illustrates the overall configuration of the printer in Example 1. [Figure 2] This figure shows the printer in the open position according to Example 1. [Figure 3] This figure shows the printer in the state where the fuser unit of Example 1 has been moved. [Figure 4]It is a diagram showing the printer when the transfer unit and tray unit of Example 1 are pulled out. [Figure 5] It is a diagram showing the printer in a state where the transfer unit of Example 1 is pulled out alone. [Figure 6] It is a diagram for explaining the movement of the transfer unit and tray unit of Example 1. [Figure 7] It is a diagram for explaining the movement of the transfer unit and tray unit of Example 1. [Figure 8] It is a diagram for explaining the overall configuration of the printer of Example 1. [Figure 9] It is an exploded view for explaining the main frame of Example 1. [Figure 10] It is a perspective view for explaining the main frame of Example 1. [Figure 11] It is a perspective view for explaining the support stay of Example 1. [Figure 12] It is a perspective view for explaining the printer of Example 1. [Figure 13] It is a diagram for explaining the relationship between the connection board, the first side plate, and the second side plate of Example 1. [Figure 14] (a) and (b) are perspective views showing the appearance of the printer of Example 1. [Figure 15] It is a diagram for explaining the relationship between the connection board and the first side plate of the comparative example. [Figure 16] It is an exploded view for explaining the main frame of Example 2. [Figure 17] It is a perspective view for explaining the main frame of Example 2. [Figure 18] It is a perspective view for explaining the printer of Example 3. [Figure 19] (a) and (b) are perspective views showing the appearance of the printer of Example 3. [Figure 20] It is a perspective view for explaining the printer of Example 4. [Figure 21] (a) and (b) are perspective views showing the appearance of the printer of Example 4.

Modes for Carrying Out the Invention

[0011] The embodiments for carrying out this invention will be described in detail below with reference to the drawings, based on examples. However, the dimensions, materials, shapes, and relative arrangements of the components described in these embodiments should be appropriately modified depending on the configuration of the device to which the invention is applied and various conditions. In other words, the scope of this invention is not intended to be limited to the following embodiments. [Examples]

[0012] [Overall structure] The printer 1 as an image forming apparatus will be described using Figure 1. Figure 1 is a diagram illustrating the overall configuration of the printer 1 according to this embodiment. In this embodiment, the printer 1 is an electrophotographic color laser beam printer that forms an image on a sheet S as a recording material.

[0013] The printer 1 comprises a main unit 1A, a scanner (exposure device) 6, and a door (opening / closing member) 20 that can be opened and closed relative to the main unit 1A. Furthermore, the printer 1 comprises a sheet feeding unit 30, a transfer unit (transfer device) 40, a tray unit (support unit) 50, and a fixing device 70. The part including the main unit 1A and the door 20 can also be called the housing 100. The housing 100 includes the exterior of the printer 1 (described later).

[0014] The main unit 1A houses the scanner 6, the sheet feeding unit 30, the transfer unit 40, the tray unit 50, and the fixing device 70.

[0015] The sheet feeding unit 30 has a loading tray (loading cassette, paper feed cassette) 31 for loading sheets S as recording material, and a supply roller 32. The loading tray 31 can be pulled out in the direction of the door 20 to replenish the sheets S. The loading tray 31 has an intermediate plate 33 configured to lift the sheets S so that they come into contact with the supply roller 32.

[0016] The tray unit 50 and the transfer unit 40 form the image (toner image) to be transferred to the sheet S. In other words, the tray unit 50 and the transfer unit 40 function as an image forming unit (IM). To put it another way, the image forming unit (IM) is housed in the housing 100 and includes the tray unit 50 and the transfer unit 40.

[0017] The tray unit 50 includes a tray (support member, drawer) 51 and cartridges PY, PM, PC, and PK. The tray 51 has a tray handle 52. The cartridges PY, PM, PC, and PK are removablely mounted on the tray 51.

[0018] Each of the cartridges PY, PM, PC, and PK is independently removable from the tray 51. Each cartridge contains yellow (Y), magenta (M), cyan (C), and black (K) toner (developer), respectively. The cartridges PY, PM, PC, and PK have the same configuration except for the color of the toner they contain. Therefore, the configuration and operation of one of the cartridges PY, PM, PC, or PK may be described, while the others are omitted. Also, when there is no need to distinguish between cartridges PY, PM, PC, and PK, they may simply be referred to as cartridge P. The tray unit 50 can be said to have multiple cartridges P and a tray 51 into which the multiple cartridges P are removablely mounted.

[0019] In this embodiment, the tray unit 50 has a plurality of photosensitive drums (image carriers) 61, a plurality of charging rollers 62 (charging members), and a plurality of developing rollers (developer carriers) 63. Specifically, the tray unit 50 has four photosensitive drums 61, four charging rollers 62, and four developing rollers 63. The rotational axis directions of the photosensitive drums 61, the developing rollers 63, and the charging rollers 62 are parallel.

[0020] The part that forms the black (K) image is called the black station (first station), the photosensitive drum 61 of the first station is called the first photosensitive drum, the developing roller 63 is called the first developing roller, and the charging roller 62 is called the first charging roller.

[0021] The part that forms the cyan (C) image is called the cyan station (second station), the photosensitive drum 61 of the second station is called the second photosensitive drum, the developing roller 63 is called the second developing roller, and the charging roller 62 is called the second charging roller.

[0022] The part that forms the magenta (M) image is called the magenta station (third station), the photosensitive drum 61 of the third station is called the third photosensitive drum, the developing roller 63 is called the third developing roller, and the charging roller 62 is called the third charging roller.

[0023] The part that forms the yellow (Y) image is called the yellow station (fourth station), the photosensitive drum 61 of the fourth station is called the fourth photosensitive drum, the developing roller 63 is called the fourth developing roller, and the charging roller 62 is called the fourth charging roller.

[0024] Cartridge PK is installed in the black station, cartridge PC in the cyan station, cartridge PM in the magenta station, and cartridge PY in the yellow station. In this embodiment, cartridge PK is referred to as the first cartridge, cartridge PC as the second cartridge, cartridge PM as the third cartridge, and cartridge PY as the fourth cartridge.

[0025] The numbers 1, 2, 3, and 4 are used for explanatory purposes to distinguish each component. Therefore, these numbers can, in principle, be rearranged as appropriate.

[0026] The photosensitive drum 61, the charging roller 62, and the developing roller 63 may be provided in either the cartridge P or the tray 51. In this embodiment, the cartridge P has the photosensitive drum 61, the charging roller 62, and the developing roller 63.

[0027] The transfer unit 40 includes a belt 41, a drive roller 46 that drives the belt 41, a primary transfer roller 42, a cleaning unit 43, and a tension roller (driven roller) 47. In this embodiment, the belt 41 is positioned below the photosensitive drum 61 and is in contact with the photosensitive drum 61 so that a primary transfer section is formed between the belt 41 and the photosensitive drum 61. The printer 1 also has a secondary transfer roller 45 that contacts the belt 41 so that a secondary transfer section is formed. The secondary transfer section is formed between the belt 41 and the secondary transfer roller 45. The rotational axis directions of the primary transfer roller 42, the drive roller 46, the tension roller 47, and the secondary transfer roller 45 are parallel. A pair of registration rollers 4 is positioned in front of the secondary transfer section.

[0028] The fixing device 70 includes a fixing unit 70b and a flapper 5. When an image forming operation is performed on the sheet S, the fixing device 70 is in the use position. The fixing device 70 is housed inside the main body 1A when in the use position. The fixing device 70 is also configured to heat the sheet S when in the use position. In this embodiment, the fixing unit 70b includes a heating unit (heating roller) 71 including a heater and a pressurizing unit (pressurizing roller) 77.

[0029] In this embodiment, at least a portion of the image forming unit is a movable unit that can move outside the housing 100. In this embodiment, the transfer unit 40 and the tray unit 50 each function as a movable unit.

[0030] The movement of the transfer unit 40 and the tray unit 50 will be explained using Figures 1, 2, 3, 4, and 5. Figure 2 shows the printer 1 with the door 20 open. Figure 3 shows the printer 1 with the fuser unit 70 moved. Figure 4 shows the printer 1 with the transfer unit 40 and the tray unit 50 pulled out. Figure 5 shows the printer 1 with the transfer unit 40 pulled out by itself.

[0031] The transfer unit 40 and the tray unit 50 are movable from the inside to the outside of the device body 1A. In the horizontal direction H, the device body 1A has a first end 1b1 with an opening 1A1 and a second end 1b2 opposite to the first end 1b1. The tray unit 50 is movable through the opening 1A1 to a first inner position inside the device body 1A and to a first outer position outside the device body 1A. The transfer unit 40 is movable through the opening 1A1 to a second inner position inside the device body 1A and to a second outer position outside the device body 1A. The opening 1A1 may include an opening through which the tray unit 50 passes and an opening through which the transfer unit 40 passes. When the transfer unit 40 moves from the second inner position to the second outer position, at least the belt 41 moves, and at least a portion of the belt 41 protrudes from the device body 1A toward the outside of the device body 1A.

[0032] The direction in which the tray unit 50 moves from the first inner position to the first outer position is called the tray removal direction Dd1, and the direction opposite to the tray removal direction Dd1 is called the tray mounting direction Da1. The tray removal direction Dd1 can be described as the direction from the second end 1b2 to the first end 1b1.

[0033] The direction in which the transfer unit 40 moves from the second inner position to the second outer position is called the transfer removal direction Dd2, and the direction opposite to the transfer removal direction Dd2 is called the transfer mounting direction Da2. In the transfer removal direction Dd2, the drive roller 46 is located downstream of the tension roller 47. The transfer removal direction Dd2 can be described as the direction from the second end 1b2 to the first end 1b1.

[0034] The tray removal direction Dd1 and the tray mounting direction Da1 are directions that intersect (preferably orthogonal to) the rotation axis direction of the photosensitive drum 61. The transfer removal direction Dd2 and the transfer mounting direction Da2 are directions that intersect (preferably orthogonal to) the rotation axis direction of the drive roller 46. The rotation axis direction of the drive roller 46 is parallel to the rotation axis direction of the photosensitive drum 61.

[0035] In the horizontal direction H, a fixing device 70 is positioned on one end of the device body 1A (the side on which the first end portion 1b1 is located).

[0036] The door 20 attached to the device body 1A is movable between a closed position and an open position. As shown in Figure 1, when the door 20 is in the closed position (closed state), the door 20 covers the opening 1A1. As shown in Figure 2, when the door 20 is in the open position (open state), the opening 1A1 is exposed.

[0037] As shown in Figure 1, when the door 20 is in the closed position, the door 20 covers the fixing device 70 attached to the main body 1A of the device. More specifically, when the door 20 is in the closed position, the upper cover portion 20b of the door 20 is located above the fixing device 70. The upper cover portion 20b of the door 20 functions as part of the exterior.

[0038] The door 20 can move between an open position and a closed position while the fixing device 70 is supported by the device body 1A. In other words, the door 20 moves from the closed position to the open position so as to move away from the fixing device 70 supported by the device body 1A. Therefore, as shown in Figure 2, when the door 20 is in the open position, the door 20 is away from the fixing device 70 supported by the device body 1A.

[0039] As will be described later, the fixing device 70 can be moved from the state in Figure 2 to the state in Figure 3 so that the opening 1A1 is widely exposed. With the door 20 and the fixing device 70 moved (Figure 3), the transfer unit 40 and the tray unit 50 can move from the inside to the outside of the device body 1A through the opening 1A1, and after the move, it will be in the state in Figure 4.

[0040] With the tray unit 50 moved outside the main body 1A of the device (Figure 4), it is permissible to remove cartridges PY, PM, PC, and PK from the tray 51 and to install cartridges PY, PM, PC, and PK onto the tray 51. This allows the user to replace cartridges PY, PM, PC, and PK with new cartridges PY, PM, PC, and PK. In this embodiment, cartridge P is detachable from the tray 51 in a direction intersecting (preferably perpendicular to) the rotation axis of the photosensitive drum 61.

[0041] Cartridges PY, PM, PC, and PK are removed from tray 51 by moving away from the transfer unit 40 relative to the tray 51. In other words, cartridges PY, PM, PC, and PK are removed from tray 51 by moving away from the transfer unit 40 relative to the tray 51. In this embodiment, the transfer unit 40 is located below the tray unit 50. Therefore, cartridges PY, PM, PC, and PK are removed from tray 51 by moving upward relative to the tray 51.

[0042] Furthermore, the transfer unit 40 can be removed from the main body 1A of the device independently of the tray unit 50, and can be replaced with a new transfer unit 40.

[0043] [Image Formation Process] The image formation operation of printer 1 will be explained using Figure 1. Printer 1 is connected to an external host device (external equipment) 400, and starts the image formation operation on sheet S based on the image signal received from the external host device 400. The external host device 400 is, for example, a personal computer, an image reader, and a facsimile machine.

[0044] When an image is formed on the sheet S, the fixing device 70 is in the use position, the tray unit 50 is in the first inner position, the transfer unit 40 is in the second inner position, and the door 20 is in the closed position. With the transfer unit 40 in the second inner position, the belt 41 can contact the photosensitive drum 61. At this time, the tray unit 50 is positioned above the transfer unit 40.

[0045] A charging voltage is applied to the charging roller 62, causing the photosensitive drum 61 to rotate. A laser corresponding to the image information is shone from the scanner 6 onto the photosensitive drum 61, exposing the surface of the photosensitive drum 61 that has been charged by the charging roller 62. As a result, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 61.

[0046] The developing roller 63 carries toner. A developing voltage is applied to the developing roller 63, and the electrostatic latent image formed on the photosensitive drum 61 is developed by the toner supplied from the developing roller 63, forming a toner image on the surface of the photosensitive drum 61. In this embodiment, the developing roller 63 develops the electrostatic latent image while in contact with the photosensitive drum 61, but the developing roller 63 may develop the electrostatic latent image with a gap between the developing roller 63 and the photosensitive drum 61.

[0047] When a full-color image is formed, toner images of each color are formed on each photosensitive drum 61.

[0048] In this embodiment, with the tray unit 50 in the first inner position, the developing roller 63 is movable between a contact position in contact with the photosensitive drum 61 and a separated position away from the photosensitive drum 61. Specifically, a switching device provided in the main body 1A switches between the developing roller 63 being in the contact position and the developing roller 63 being in the separated position. This allows the developing roller 63 to be kept away from the photosensitive drum 61 when no image forming operation is being performed.

[0049] Furthermore, printer 1 can perform monochrome printing with the developing roller 63 and photosensitive drum 61 corresponding to cartridge PK in contact, and with the developing roller 63 and photosensitive drum 61 corresponding to cartridges PY, PM, and PC separated. In addition, printer 1 can perform full-color printing with the photosensitive drum 61 and belt 41 corresponding to cartridges PY, PM, PC, and PK in contact.

[0050] The toner images formed on each photosensitive drum 61 are transferred onto the belt 41 by the primary transfer roller 42 in the primary transfer section and transported toward the secondary transfer section formed by the belt 41 and the secondary transfer roller 45.

[0051] Meanwhile, the main body 1A of the device has a transport path (first path, first transport path) 1c through which the sheet S heading toward the fixing device 70 passes. The door 20 also has a double-sided transport path (second path, second transport path) 20a through which the sheet S that has passed through the fixing device 70 passes. When the door 20 is closed, it covers the transport path 1c. When the door 20 is opened, the transport path 1c and the double-sided transport path 20a are exposed (Figure 2).

[0052] In the sheet feeding unit 30, one sheet S is separated and fed from the sheets S loaded on the loading tray 31 by the supply roller 32 at a predetermined timing, and the skew is corrected by the registration roller pair 4. The sheet S is then transported through the transport path 1c toward the secondary transfer unit and the fixing device 70.

[0053] In the secondary transfer section, the toner image is transferred from the belt 41 to the sheet S. Toner that is not transferred to the sheet S is removed from the belt 41 by a cleaning blade (cleaning member) 43A provided in the cleaning section 43.

[0054] The sheet S onto which the toner image has been transferred in the secondary transfer section is transported toward the fuser unit 70. In the fuser unit 70, the sheet S is heated and pressurized in the fuser section 70b, and the toner image is fixed to the sheet S. The sheet S with the fixed toner image is transported toward the flapper 5, which acts as a path switching section.

[0055] The flapper 5 is movable between a paper discharge position that guides the sheet S that has passed through the fuser 70 toward the paper discharge path 1d, and a reversal position that guides it toward the reversal path 1e.

[0056] When single-sided printing is performed, in which an image is formed on one side of the sheet S, the sheet S is guided by the flapper 5 to the paper output path 1d and discharged into the output tray 1f formed on the top of the main body 1A of the device.

[0057] On the other hand, when double-sided printing is performed in which an image is printed on one side and the other side of the sheet S, the sheet S is guided to the reversal path 1e by the flapper 5. After the sheet S is guided to the reversal path 1e, the transport direction of the sheet S is reversed, and the sheet S is transported through the double-sided transport path 20a formed in the door 20 toward the secondary transfer section. In the secondary transfer section, after the toner image is transferred to the back side of the sheet S, the sheet S passes through the fuser 70, is guided to the paper discharge path 1d by the flapper 5, and is discharged into the discharge tray 1f of the main body 1A.

[0058] [Removal of tray unit and transfer unit, and placement of fixing device] Figures 1, 2, 3, 4, and 5 will be used to explain the removal of the tray unit 50 and the transfer unit 40 from the main body 1A of the apparatus, and the arrangement of the fixing device 70.

[0059] As described above, the fuser unit 70 of the printer 1 is located horizontally on one end of the device body 1A. The transfer unit 40 and the tray unit 50 move from one end of the device body 1A to the outside of the device body 1A through the opening 1A1.

[0060] In other words, with respect to the horizontal direction H, the fixing device 70 is closer to the first end 1b1 than to the second end 1b2. That is, with respect to the horizontal direction H, the distance between the fixing device 70 and the first end 1b1 is shorter than the distance between the fixing device 70 and the second end 1b2. The fixing device 70 is positioned closer to the first end 1b1 than to the center of the device body 1A in the horizontal direction H, and it can be said that the distance between the first end 1b1 and the fixing device 70 in the horizontal direction H is shorter than the distance between the first end 1b1 and the center of the device body 1A.

[0061] Furthermore, as described above, when the tray unit 50 moves from the first inner position to the first outer position, the direction of movement of the tray unit 50 is in a direction that intersects the rotation axis of the photosensitive drum 61. At this time, the tray unit 50 moves away from the second end 1b2.

[0062] As described above, when the transfer unit 40 moves from the second inner position to the second outer position, the direction of movement of the transfer unit 40 is in a direction that intersects the rotation axis of the drive roller 46. At this time, the transfer unit 40 moves away from the second end 1b2.

[0063] As described above, the door 20 in this embodiment covers the opening 1A1 when closed and also covers at least a portion of the sheet S transport path 1c. The door 20 also has a double-sided transport path 20a. If a sheet S jams (hereinafter referred to as a jam), the user of the printer 1 can remove the sheet S from one end of the device body 1A to clear the jam. Specifically, the door 20 can be moved to the open position to access the inside of the device body 1A and remove the sheet S. Also, if a portion of the sheet S that has passed through the fuser 70 is exposed to the outside of the device body 1A, the sheet S can be pulled from the outside of the device body 1A and removed without opening the door 20.

[0064] Furthermore, the user of printer 1 can move the transfer unit 40 and tray unit 50 from one end of the main unit 1A to the outside of the main unit 1A to perform tasks such as checking the condition of the transfer unit 40 and cartridge P, maintenance, and replacement.

[0065] In other words, the printer 1 has a fuser unit 70 located at one end of the main body 1A, while the transfer unit 40 and tray unit 50 can be moved in and out of the main body 1A through the same end. As a result, the user can clear jams, access the fuser unit 70, and operate the transfer unit 40 and tray unit 50 from one direction.

[0066] In this embodiment, the printer 1 has its front facing the door 20. Therefore, it is sufficient to have enough space to perform tasks such as clearing jams and operating the transfer unit 40 and tray unit 50 from the front of the printer 1. On the other hand, it is not necessary to have enough space to perform these tasks from the left, right, back, or top of the printer 1. Therefore, the printer 1 can be installed in a space-saving manner.

[0067] If the transfer unit 40 or tray unit 50 is pulled out from the other end of the device body 1A, the user needs to access both ends of the device body 1A to clear the jam and pull out the transfer unit 40 or tray unit 50. Similarly, if one of the transfer unit 40 or tray unit 50 is pulled out from one end of the device body 1A and the other is pulled out from the other end, the user also needs to access both ends of the device body 1A. As a result, space is required to work from both the front and the back of the device body 1A, increasing the area required to install the printer 1.

[0068] Furthermore, in this embodiment, the sheets S can be replenished from one end of the device body 1A. Therefore, it is sufficient to have space to replenish the sheets S from the front of the printer 1, and the printer 1 can be installed in a space-saving manner.

[0069] [Relationship between tray unit and fuser] The relationship between the tray unit 50 and the fixing device 70 will be explained using Figures 1, 2, 3, 4, 6, and 7. Figures 6 and 7 illustrate the movement of the transfer unit 40 and the tray unit 50.

[0070] The tray unit 50 passes through a predetermined space when moving from a first inner position where an image forming operation is performed on the sheet S to a first outer position where cartridge P can be replaced. The space through which the tray unit 50 passes when moving from the first inner position to the first outer position is called the first space (the space through which the tray unit 50 moves). The first space can also be called the path or trajectory (first movement path, first movement trajectory) through which the tray unit 50 passes when moving from the first inner position to the first outer position.

[0071] As the transfer unit 40 moves from the second inner position where the image forming operation on the sheet S is performed to the second outer position, it passes through a predetermined space. The space through which the transfer unit 40 moves from the second inner position to the second outer position is called the second space (the movement space of the transfer unit 40). The second space can also be called the path or trajectory (second movement path, second movement trajectory) through which the transfer unit 40 moves from the second inner position to the second outer position.

[0072] The position (usage position) of the fixing device 70 when the image forming operation is performed on the sheet S, and the first space and the second space have the following relationship.

[0073] In other words, as shown in Figures 6 and 7, at least a portion of the fixing device 70 in the operating position overlaps with the first space. To put it another way, when the fixing device 70 is in the operating position, at least a portion of the fixing device 70 is inside the first space.

[0074] In this embodiment, at least a portion of the fixing device 70 overlaps with the space through which the cartridge P passes when the tray unit 50 moves from the first inner position to the first outer position, but it may also be arranged to overlap with the space through which the tray 51 passes.

[0075] This allows the main body of the device 1A to be made smaller compared to a configuration in which the fixing device 70 at the point of use is located outside the first space.

[0076] As shown in Figure 6, in this embodiment, when the door 20 is closed, at least a portion of the double-sided transport path 20a overlaps with the first space. That is, when the door 20 is closed, at least a portion of the double-sided transport path 20a is inside the first space.

[0077] As described above, at least a portion of the fixing device 70 in the use position is inside the first space. Therefore, when the fixing device 70 is in the use position, the tray unit 50 is restricted from moving from the first inner position to the first outer position. On the other hand, the fixing device 70 is configured to be retractable from the use position. When the fixing device 70 is retracted from the use position, the tray unit 50 is permitted to move from the first inner position to the first outer position. When the tray unit 50 moves from the first inner position to the first outer position, the tray unit 50 passes below the fixing device 70. The fixing device 70 is outside the second space in both the use position and the retracted position. Therefore, in both the use position and the retracted position, the transfer unit 40 can move from the second inner position to the second outer position. When the transfer unit 40 moves from the second inner position to the second outer position, the transfer unit 40 passes below the fixing device 70.

[0078] The fixing device 70 has a fixing frame 70a that supports the fixing section 70b. When the fixing device 70 is moved away from the operating position, the fixing frame 70a is displaced relative to the device body 1A while supporting the fixing section 70b.

[0079] When pulling the tray unit 50 out of the main body 1A of the device, first, the door 20 is moved to the open position as shown in Figure 2. In this embodiment, with the fixing device 70 in the use position, the door 20 can be moved to the open position and the closed position. Then, with the door 20 in the open position, and with the door 20 in the open position, the fixing device 70 is moved from the use position to the retracted position so as to move it out of the first space as shown in Figure 3.

[0080] In the printer 1 of this embodiment, the fuser unit 70 is movable between a working position and a retracted position when it is moved away from the working position, while attached to the main unit 1A of the device. In this embodiment, when the fuser unit 70 is in the retracted position, the entire fuser unit 70 is located outside the first space.

[0081] The fuser unit 70 is lifted from its operating position and positioned in a retracted position above the operating position. In other words, the retracted position is higher than the operating position. As shown in Figure 7, when the fuser unit 70 is in the retracted position, at least a portion of the fuser unit 70 protrudes from the device body 1A toward the outside. Furthermore, when the fuser unit 70 is in the retracted position, at least a portion of the fuser unit 70 is higher than the position of the upper cover portion 20b of the cover 20 in the closed position. This allows the size of the printer 1 to be kept small in the vertical direction V when the fuser unit 70 is in the operating position, while the movement of the fuser unit 70 to the retracted position secures space for the tray unit 50 to move. Note that when the fuser unit 70 is in the retracted position, the door 20 is restricted from taking the closed position.

[0082] Specifically, the printer 1 has a connecting member (fuser connecting member, fuser link, arm) 75 that is movably connected to the main body 1A of the device. The fuser device 70 is connected to the main body 1A of the device via the connecting member 75.

[0083] The connecting member 75 is rotatable about a rotation center 75A, and when the tray unit 50 is pulled out to the outside of the device body 1A, the connecting member 75 is moved to the outside of the first space. A fixing device 70 is rotatably connected to one end of the connecting member 75, and the other end of the connecting member 75 is rotatably connected to the device body 1A about a rotation center 75A. The fixing device 70 is movable from the use position to the retracted position and from the retracted position to the use position while supported by the connecting member 75 (connected to the device body 1A via the connecting member 75). The connecting member 75 is configured to be movable (oscillating) relative to the device body 1A and the fixing device 70. In other words, the fixing device 70 is connected to the device body 1A via the connecting member 75. As a result, the amount of movement of the fixing device 70 when it moves between the retracted position and the use position can be increased compared to a configuration in which the fixing device 70 is directly connected to the device body 1A.

[0084] As shown in Figure 7, when the tray unit 50 moves from the first inner position to the first outer position, the angle between the direction of movement of the tray unit 50 and the horizontal direction H is smaller than the angle between the direction of movement of the tray unit 50 and the vertical direction V. Furthermore, when the fixing device 70 moves from the use position to the retracted position, the amount of movement of the fixing device 70 in the vertical direction V is greater than the amount of movement of the fixing device 70 in the horizontal direction H. In other words, when the fixing device 70 moves from the use position to the retracted position, the amount of movement of the fixing device 70 in the direction perpendicular to the direction of movement of the tray unit 50 is greater than the amount of movement of the fixing device 70 in the direction parallel to the direction of movement of the tray unit 50.

[0085] Furthermore, the fixing device 70 may be attached to the device body 1A via a guide fixed to the device body 1A, and move between the operating position and the retracted position. In this case, the shape of the guide is arbitrary.

[0086] However, the method for moving the fixing device 70 outside the first space is not limited to this. For example, the fixing device 70 may be detachable from the main body 1A so as to be moved out of the operating position, thereby moving the fixing device 70 outside the first space. In other words, the fixing device 70 may be positioned outside the first space by separating it from the main body 1A and the door 20 (separating it from the housing 100). Alternatively, the fixing device 70 may be connected to the door 20, and the fixing device 70 may be moved outside the first space by opening the door 20.

[0087] The horizontal direction H described above can be called the direction perpendicular to the vertical direction V. Furthermore, the horizontal direction H described above is the direction that intersects (preferably perpendicular to) the rotation axis direction of the photosensitive drum 61 and the direction that intersects (preferably perpendicular to) the rotation axis direction of the drive roller 46. Figures 1 to 7 can be said to be views of the printer 1 as seen in the direction of the rotation axis direction of the photosensitive drum 61. The rotation axis direction of the photosensitive drum 61 can also be called the width direction. The width direction is parallel to the rotation axis direction of the transport roller that transports the sheet S. In other words, the rotation axis direction of the photosensitive drum 61, the width direction, and the rotation axis direction of the transport roller are parallel to each other.

[0088] In the following explanation, with respect to the vertical direction V, the top of the printer 1 is referred to as the top side, and the bottom side as the bottom side. With respect to the horizontal direction H, one side of the printer 1 is referred to as the front side, and the other side as the rear side. The first end 1b1 is located on the front side, and the second end 1b2 is located on the rear side. When viewing the printer 1 from the front side, with respect to the width direction, the right side of the printer 1 is referred to as the right side, and the left side as the left side.

[0089] <Frame structure> The frame structure of printer 1 will be explained using Figures 8, 9, and 10. Figure 8 is a diagram illustrating the overall configuration of the printer of Example 1. Figure 9 is an exploded view illustrating the main frame of Example 1. Figure 10 is a perspective view illustrating the main frame of Example 1.

[0090] The casing 100 of printer 1 includes an exterior part E1 and a main frame F. The main frame F is included in the main body 1A of the device. The exterior part E1 is at least a portion of the part of printer 1 that is exposed to the outside. The door 20 functions as part of the exterior part E1.

[0091] As shown in Figures 9 and 10, the main frame F includes a first side plate 91 and a second side plate 90. The first side plate 91 and the second side plate 90 support the conveying rollers that transport the sheet S. In this embodiment, the first side plate 91 and the second side plate 90 are configured to guide the movement of the tray unit 50 and the transfer unit 40. The first side plate 91 and the second side plate 90 are also configured to support the tray unit 50 and the transfer unit 40.

[0092] The first side plate 91 includes a first surface 91a, and the second side plate 90 includes a second surface 90a. The first surface 91a and the second surface 90a intersect in the direction of the rotation axis of the photosensitive drum 61 of the photosensitive drum 6. In other words, the direction in which the first surface 91a expands (first stretching direction) and the direction in which the second surface 90a expands (second stretching direction) intersect in the direction of the rotation axis and width direction of the photosensitive drum 61. With respect to the rotation axis direction of the photosensitive drum 61, the first surface 91a and the second surface 90a face each other, and the image forming unit IM is positioned between the first surface 91a and the second surface 90a.

[0093] The first side plate 91 has a first outer edge 91b. A recess 91b1 is formed in the first outer edge 91b. When viewed in the direction of the rotation axis of the photosensitive drum 61, the first outer edge 91b is located on the outermost side of the first side plate 91. Similarly, the second side plate 90 has a second outer edge 90b. When viewed in the direction of the rotation axis of the photosensitive drum 61, the second outer edge 90b is located on the outermost side of the second side plate 90.

[0094] The first outer edge 91b includes a first extended portion 91e extending in the direction of the rotation axis of the photosensitive drum 61. The first extended portion 91e extends outward from the main frame F relative to the first surface 91a. The first extended portion 91e includes a first front extended portion 91ef, a first top extended portion 91et, a first bottom extended portion 91eb, an upper extended portion 91eR1, a lower extended portion 91eR2, and an intermediate extended portion 91eR3. The first extended portion 91e also includes a connecting portion 91d, and the upper extended portion 91eR1 and the intermediate extended portion 91eR3 are connected via the connecting portion 91d.

[0095] The intermediate extension 91eR3 can be called a forming part that creates the recess 91b1. Similarly, the connecting part 91d can also be called a forming part that creates the recess 91b1. Specifically, the intermediate extension 91eR3 and the connecting part 91d are positioned between the upper extension 91eR1 and the lower extension 91eR2. As shown in Figure 9, the intermediate extension 91eR3 and the connecting part 91d are positioned set back from the imaginary straight line LI connecting the upper extension 91eR1 and the lower extension 91eR2.

[0096] The recess 91b1 can be defined as the region enclosed by the virtual straight line LI, the intermediate extension portion 91eR3, and the connecting portion 91d.

[0097] The recess 91b1 is located between the upper extension 91eR1 and the lower extension 91eR2. The upper extension 91eR1 and the lower extension 91eR2 are not directly connected.

[0098] The first front extension 91ef, the upper extension 91eR1, the lower extension 91eR2, and the intermediate extension 91eR3 each extend in a direction that intersects the horizontal direction (more preferably the vertical direction) when viewed in the direction of the rotation axis of the photosensitive drum 61. Note that these do not necessarily have to be parallel to each other.

[0099] The first top extension portion 91et and the first bottom extension portion 91eb each extend in a direction that intersects the vertical direction (more preferably the horizontal direction) when viewed in the direction of the rotation axis of the photosensitive drum 61. These extensions do not necessarily have to be parallel to each other.

[0100] The first side plate 91 is preferably formed from sheet metal. In this embodiment, the first extended portion 91e is formed by plastic deformation (e.g., bending, drawing) of the sheet metal. The rigidity of the first side plate 91 is increased by forming the first extended portion 91e on the front, top, bottom, and back sides of the first outer edge 91b of the first side plate 91. Furthermore, the first top extended portion 91et and the first front extended portion 91ef are connected by a curved connecting portion 91z, thereby increasing the rigidity of the first side plate 91 against bending and twisting.

[0101] The second outer edge 90b includes a second extended portion 90e extending in the direction of the rotation axis of the photosensitive drum 61. The second extended portion 90e extends outward from the main frame F relative to the second surface 90a. The second extended portion 90e includes a second front extended portion 90ef, a second top extended portion 90et, a second bottom extended portion 90eb, and a second back extended portion 90eR.

[0102] The second front extension 90ef and the second back extension 90eR each extend in a direction that intersects the horizontal direction (more preferably the vertical direction) when viewed in the direction of the rotation axis of the photosensitive drum 61. Note that these do not necessarily have to be parallel to each other.

[0103] The second top extension portion 90et and the second bottom extension portion 90eb each extend in a direction that intersects the vertical direction (more preferably the horizontal direction) when viewed in the direction of the rotation axis of the photosensitive drum 61. Note that they do not have to be parallel to each other.

[0104] The second side plate 90 is preferably formed from sheet metal. In this embodiment, the second extension portion 90e is formed by plastically deforming sheet metal. The rigidity of the second side plate 90 is increased by forming the second extension portion 90e on the front, top, bottom, and back sides of the second outer edge 90b of the second side plate 90. Furthermore, the second top extension portion 90et and the second front extension portion 90ef are connected by a curved connecting portion 90z, thereby increasing the rigidity of the second side plate 90 against bending and twisting.

[0105] The main frame F includes support stays (lower rear stay, stay) 92, upper rear stay 94, bottom stay 95, first top stay 93, second top stay 97, and main stay 96. Each of the support stays 92, upper rear stay 94, bottom stay 95, first top stay 93, second top stay 97, and main stay 96 is connected to the first side plate 91 and the second side plate 90. More specifically, each of the support stays 92, upper rear stay 94, bottom stay 95, first top stay 93, second top stay 97, and main stay 96 is coupled to the first side plate 91 and the second side plate 90 and fixed to the first side plate 91 and the second side plate 90.

[0106] The support stay 92, upper rear stay 94, bottom stay 95, first top stay 93, second top stay 97, and main stay 96 are preferably formed from sheet metal. The support stay 92, upper rear stay 94, bottom stay 95, first top stay 93, second top stay 97, main stay 96, first side plate 91, and second side plate 90 are each joined to each other at the joint W. Crimping, welding, adhesive, etc., can be used as the joining method at the joint W. It is not necessary to use the same joining method at all joints W. Also, fastening members such as screws and rivets may be used as the joining method at the joint W. In the following description, joining means that one member is fixed to the other member so that it does not move relative to it.

[0107] The bottom stay 95 has a horizontal plane 95a perpendicular to the first surface 91a and the second surface 90a. The bottom stay 95 is connected to the first outer edge 91b, more specifically to the lower extension 91eR2. The bottom stay 95 may also be connected to the first bottom extension 91eb and the first front extension 91ef. The first side plate 91 is reinforced by fixing the bottom stay 95 to the first outer edge 91b so as to straddle the corner between the first bottom extension 91eb and the lower extension 91eR2, and the corner between the first bottom extension 91eb and the first front extension 91ef.

[0108] The bottom stay 95 is connected to the second outer edge 90b, and more specifically to the second back extension 90eR. The bottom stay 95 may also be connected to the second bottom extension 90eb and the second front extension 90ef. The second side plate 90 is reinforced by fixing the bottom stay 95 to the second outer edge 90b so as to straddle the corner between the second bottom extension 90eb and the second back extension 90eR, and the corner between the second bottom extension 90eb and the second front extension 90ef.

[0109] The paper feed cassette 31 is positioned on the horizontal surface 95a of the bottom stay 95. As shown in Figure 8, one end of the paper feed cassette 31 can be made to protrude outside the housing 100. This allows the paper feed cassette 31 to accommodate large-sized sheets S.

[0110] The upper rear stay 94 is connected to the first outer edge 91b, and more specifically to the first top extension 91et and the upper extension 91eR1. The first side plate 91 is reinforced by fixing the upper rear stay 94 to the first outer edge 91b so as to straddle the corners of the first top extension 91et and the upper extension 91eR1.

[0111] The upper rear stay 94 is connected to the second outer edge 90b, and more specifically to the second top extension 90et and the second rear extension 90eR. The second side plate 90 is reinforced by fixing the upper rear stay 94 to the second outer edge 90b so as to straddle the corners of the second top extension 90et and the second rear extension 90eR.

[0112] The support stay 92 is connected to the first side plate 91 at the joint W1 and to the second side plate 90 at the joint W0. In this embodiment, the support stay 92 is also connected to the upper rear stay 94 at the joint W4. The number of joints W1, W0, and W4 may be one, but it is preferable to have multiple joints.

[0113] The support stay 92 is connected to the first outer edge 91b, and more specifically to the lower extension 91eR2 and the intermediate extension 91eR3. The lower extension 91eR2 and the intermediate extension 91eR3 each function as a receiving portion extending in the direction of the rotation axis of the photosensitive drum 61. The first side plate 91 is reinforced by the support stay 92 being fixed to the upper rear stay 94, the lower extension 91eR2 and the intermediate extension 91eR3.

[0114] The support stay 92 is connected to the second outer edge 90b, and more specifically to the second rear extension 90eR. The support stay 92 is also connected to the second surface 90a. The second side plate 90 is reinforced by the support stay 92 being fixed to the upper rear stay 94, the second rear extension 90eR, and the second surface 90a.

[0115] The first top stay 93 is positioned on the top of the scanner 6. The first top stay 93 is connected to the first outer edge 91b, and more specifically to the first top extension 91et. The first top stay 93 may also be connected to the first surface 91a.

[0116] The first top stay 93 is connected to the second outer edge 90b, and more specifically to the second top extension 90et. The first top stay 93 may also be connected to the second surface 90a.

[0117] The second top stay 97 is coupled to the first surface 91a and the second surface 90a. The second top stay 97 may support the scanner 6. The main stay 96 is located between the paper feed cassette 31 and the intermediate transfer unit 40 and is coupled to the first surface 91a and the second surface 90a.

[0118] As described above, the main frame F has high rigidity because the support stay 92, upper rear stay 94, bottom stay 95, first top stay 93, second top stay 97, and main stay 96 are connected to the first side plate 91 and the second side plate 90. The image forming unit IM and scanner 6 are housed in such a main frame F, so that high positional accuracy is maintained relative to each other.

[0119] The number of stays connected to the first side plate 91 and the second side plate 90 may be less or more than those described above.

[0120] <Support Stay> The support stay 92 of this embodiment will be described in more detail using Figures 9, 10, and 11. Figure 11 is a perspective view illustrating the support stay 92 of Embodiment 1.

[0121] The support stay 92 has a mounting portion 92a for attaching a connection board (external connection board) 83, which will be described later, and a first protective portion 92b1 and a second protective portion 92b2. The first protective portion 92b1 and the second protective portion 92b2 extend in a direction intersecting the mounting portion 92a. The support stay 92 also has a third protective portion 92b3. The third protective portion 92b3 extends in a direction intersecting the first protective portion 92b1, the second protective portion 92b2, and the mounting portion 92a.

[0122] The mounting portion 92a is connected to the intermediate extension portion 91eR3 at the connecting portion W(W1).

[0123] The first protective portion 92b1 is connected to the first connected portion 92c1. The first connected portion 92c1 is a bent portion relative to the first protective portion 92b1. The first connected portion 92c1 is connected to the upper rear stay 94 at the joint portion W(W4).

[0124] The second protective portion 92b2 is connected to the second connected portion 92c2. The second connected portion 92c2 is a bent portion relative to the second protective portion 92b2. The second connected portion 92c2 is connected to the lower extended portion 91eR2 at the joint portion W(W1).

[0125] The connecting portion 92f is connected to the second protective portion 92b2. The connecting portion 92f is a bent portion relative to the second protective portion 92b2. The connecting portion 92f overlaps with the third protective portion 92b3 and, as shown in Figure 10, is joined together with the third protective portion 92b3 to the second surface 90a at the connecting portion W(W0).

[0126] The third protective portion 92b3 is connected to the third connected portion 92c3. The third connected portion 92c3 is a bent portion relative to the third protective portion 92b3. The third connected portion 92c3 is connected to the second back extension portion 90eR at the joint portion W(W0).

[0127] The distance between the first protective section 92b1 and the second protective section 92b2 is longer than the distance h between the boundary between the intermediate extension section 91eR3 and the connecting section 91d and the lower extension section 91eR2.

[0128] The step between the mounting portion 92a and the second connected portion 92c2 is the same as the step between the intermediate extension portion 91eR3 and the lower extension portion 91eR2. The step between the mounting portion 92a and the third connected portion 92c3 is the same as the step between the intermediate extension portion 91eR3 and the second back extension portion 90eR. When the support stay 92 is attached to the first side plate 91 and the second side plate 90, the intermediate extension portion 91eR3 and the mounting portion 92a come into contact, the lower extension portion 91eR2 and the second connected portion 92c2 come into contact, and the second back extension portion 90eR and the third connected portion 92c3 come into contact.

[0129] The support stay 92 can also be said to have the function of reinforcing the first side plate 91 around the recess 91b1.

[0130] <Electric Scale> The electrical components provided in printer 1 will be explained using Figure 12. Figure 12 is a perspective view illustrating printer 1 according to Embodiment 1.

[0131] Printer 1 has an image motor M1, a paper feed motor M2, and a fuser motor M3. Each of the image motor M1, paper feed motor M2, and fuser motor M3 is an example of a drive source. Printer 1 has a fuser drive unit D2 which includes the fuser motor M3. Printer 1 has an image drive unit D1 which includes the image motor M1 and the paper feed motor M2. The image drive unit D1 and the fuser drive unit D2 are supported by a second side plate 90.

[0132] The driving force of the image-making motor M1 is transmitted to the tray unit 50. In this embodiment, the image-making motor M1 also drives the drive roller 46 of the transfer unit 40. The paper feed motor M2 drives the intermediate plate 33 to lift the recording material S in the paper feed cassette 31 up to the supply roller 32. The paper feed motor M2 also drives the supply roller 32. The fuser motor M3 drives the pressure roller (fusing roller) 77 provided in the fuser device 70.

[0133] Printer 1 comprises a power supply board 82, a connection board (formatter) 83, and a control board 81. The power supply board 82 is supplied with AC voltage from the commercial power supply via an inlet 82a. The power supply board 82 has electrical components. Examples of electrical components include capacitors and transformers. The power supply board 82 has the function of a so-called AC-DC converter, which converts AC voltage to DC voltage. Therefore, the power supply board 82 has rectifier elements, smoothing capacitors, transformers, switching elements, and control ICs. The power supply board 82 is supported by a second side plate 90.

[0134] The connection board 83 includes a connector (connection connector, external connection connector) 83a that allows electrical connection to an external device (external equipment) 400, and a wiring board 83b on which the connector 83a is attached. The connection board 83 is supported by a support stay 92. The wiring board 83b has a mounting surface 83b1 on which the connector 83a is mounted.

[0135] The mounting surface 83b1 extends along the vertical direction. The angle (narrow angle) between the mounting surface 83b1 of the connecting board 83 and the vertical direction can be less than 30 degrees. The mounting surface 81b1 of the connecting board 83 may be parallel to the vertical direction. The mounting surface 83b1 extends along the rotation axis direction of the photosensitive drum 61. The mounting portion 92a of the support stay 92 extends along the mounting surface 83b1. The angle (narrow angle) between the mounting surface 83b1 of the connecting board 83 and the rotation axis direction of the photosensitive drum 61 can be less than 30 degrees. The mounting surface 81b1 of the connecting board 83 and the rotation axis direction of the photosensitive drum 61 may be parallel.

[0136] The mounting portion 92a of the support stay 92 extends along the mounting surface 83b1. The angle (narrow angle) between the direction in which the mounting portion 92a extends and the mounting surface 83b1 can be less than 30 degrees. The direction in which the mounting portion 92a extends and the mounting surface 81b1 may be parallel.

[0137] The connection board 83 may have at least one electrical element 83c. The at least one electrical element 83c may include multiple electrical elements. The at least one electrical element 83c may include an arithmetic unit such as a central processing unit (CPU), and a storage device such as random access memory (RAM) or read-only memory (ROM). The at least one electrical element 83c is mounted on the mounting surface 81b1.

[0138] Connector 83a is electrically connected to the part to be connected to it. Connector 83a can be connected to, for example, terminals of a local area network communication cable or terminals compliant with the Universal Serial Bus standard in the direction of the rotation axis of the photosensitive drum 61. Examples of external devices 400 include storage devices, communication devices, and devices capable of outputting print instructions to the printer 1 (e.g., personal computers or servers). In this embodiment, the connection board 83 can generate an image signal based on the print instructions (image information) sent from the external device 400 connected via connector 83a.

[0139] As shown in Figure 12, with respect to the rotation axis direction of the photosensitive drum 61, the connecting board 83 is positioned between the first side plate 91 and the second side plate 90, and the connector 83a is closer to the first side plate 91 than to the second side plate 90.

[0140] Furthermore, with respect to the rotation axis direction of the photosensitive drum 61, the intermediate position CP is defined as the position midway between the first surface 91a and the second surface 90a. In other words, with respect to the rotation axis direction of the photosensitive drum 61, the distance between the intermediate position CP and the first surface 91a is equal to the distance between the intermediate position CP and the second surface 90a. And, with respect to the rotation axis direction of the photosensitive drum 61, the connector 83a is closer to the first surface 91a than to the intermediate position CP.

[0141] The control board 81 may have a processing unit such as a central processing unit (CPU), and a storage device such as random access memory (RAM) or read-only memory (ROM). The control board 81 is configured to receive signals such as image signals output from the connection board 83. In this embodiment, the control board 81 is configured to control the image motor M1, the paper feed motor M2, and the fuser motor M3. The control board 81 has a CPU and a drive circuit that control the driving of the image motor M1, the paper feed motor M2, and the fuser motor M3.

[0142] The control board 81 is positioned between the first side plate 91 and the second side plate 90 in the direction of the rotation axis of the photosensitive drum 61 and is supported by the first top stay 93.

[0143] In this embodiment, the power supply board 82 and the control board 81 are connected by a cable K2. DC voltages of 24V and 3.3V are supplied to the control board 81 via cable K2.

[0144] In this embodiment, the power supply board 82 and the control board 81 are connected by cable FFC2. Cable FFC3 is a flexible flat cable. Signals controlling the operation of the power supply board 82 are transmitted from the control board 81 via cable FFC2. These signals include signals that change the operating mode of the AC-DC converter of the power supply board 82 when the printer 1 is in power-saving mode.

[0145] In this embodiment, the control board 81 and the connection board 83 are connected by a cable K1. A DC voltage of 3.3V is supplied from the control board 81 to the connection board 83 via this cable K1, causing the control elements (e.g., the central processing unit) within the connection board 83 to operate.

[0146] The connection board 83 is connected to the control board 81 via the cable FFC1. Cable FFC1 is a flexible flat cable, and the image signal generated by the connection board 83 is sent to the control board 81 through this cable FFC1.

[0147] Furthermore, the control board 81 in this embodiment has the function of generating a high voltage that is supplied to the cartridge P and the transfer unit 40.

[0148] The control board 81 is an example of a first connected board connected to the connection board 83, and the power supply board 82 is an example of a second connected board connected to the first connected board. In this embodiment, the direction in which the connection board 83 expands, the direction in which the control board 81 expands, and the direction in which the power supply board 82 expands intersect with each other.

[0149] As shown in Figure 8, the connection board 83 is located above the paper feed cassette 31. The connection board 83 is also located below the scanner 6. Furthermore, the connection board 83 is located below the output tray 1f.

[0150] As described above, the image-making drive unit D1 having motors M1 to M3, the fixing drive unit D2, and the power supply board 82 having a transformer are supported by the second side plate 90. Since the second side plate 90 does not have a shape corresponding to the recess 91b1, it is suitable for stably supporting these components which are relatively heavy.

[0151] <Layout of connection boards> The arrangement of the connection board 83 will be explained using Figures 12, 13, 14(a), and 14(b).

[0152] Figure 13 shows the relationship between the connection board 83 and the first side plate 91 and the second side plate 90. Specifically, it shows the connection board 83 and the first side plate 91 and the second side plate 90 as viewed in the direction of the rotation axis of the photosensitive drum 61. Figures 14(a) and (b) are perspective views showing the external appearance of the printer 1. In Figure 13, the support stay 92 is drawn with a dotted line.

[0153] In this embodiment, the connection board 83 functions as a communication board connected to external devices 400 such as computers and servers. The connection board 83 can be connected to the external devices 400 via cables or the like to enable communication.

[0154] As shown in Figures 14(a) and (b), the connector 83a is exposed to the outside of the housing 100 (outside the printer 1) and is accessible from outside the housing 100. Specifically, the outer casing E1 has an exposed portion E1a formed therein to expose the connector 83a to the outside of the housing 100.

[0155] With respect to the rotation axis direction of the photosensitive drum 61, at least a portion of the connecting board 83 is positioned between the first side plate 91 and the second side plate 90. In this embodiment, with respect to the rotation axis direction of the photosensitive drum 61, the connector 83a is positioned between the first side plate 91 and the second side plate 90. The connector 83a is provided with an interface portion 83a1. In this embodiment, with respect to the rotation axis direction of the photosensitive drum 61, the entire connecting board 83 is positioned between the first side plate 91 and the second side plate 90.

[0156] The interface portion 83a1 includes a projection or opening that engages with the terminals connected to the connector 83a. This establishes an electrical connection between the connector 83a and the various terminals. As described above, the various terminals are detachably attached to the interface portion 83a1 in the direction of the rotation axis of the photosensitive drum 61. Therefore, the interface portion 83a1 faces in the direction of the rotation axis of the photosensitive drum 61.

[0157] As shown in Figure 13, when viewed in the direction of the rotation axis of the photosensitive drum 61, the connector 83a overlaps with the second side plate 90. Also, when viewed in the direction of the rotation axis of the photosensitive drum 61, the connector 83a overlaps with the recess 91b1 formed in the first outer edge 91b of the first side plate 91. In other words, when viewed in the direction of the rotation axis of the photosensitive drum 61, the connector 83a is housed inside the recess 91b1.

[0158] As shown in Figure 13, when viewed in the direction of the rotation axis of the photosensitive drum 61, the virtual straight line LI connecting the upper extension portion 91eR1 and the lower extension portion 91eR2 coincides with the second outer edge 90b of the second side plate 90, more specifically the second back extension portion 90eR. The intermediate extension portion 91eR3 can be said to be the portion that is set back from the virtual straight line LI. In other words, when viewed in the direction of the rotation axis of the photosensitive drum 61, the intermediate extension portion 91eR3 is further from the second end portion 1b2 than the virtual straight line LI. Also, when viewed in the direction of the rotation axis of the photosensitive drum 61, the connector 83a is positioned between the virtual straight line LI and the intermediate extension portion 91eR3.

[0159] If the connection board 83 has multiple connectors 83a, the multiple connectors 83a overlap with the second side plate 90. Also, when viewed in the direction of the rotation axis of the photosensitive drum 61, the multiple connectors 83a overlap with the recess 91b1 formed on the first outer edge 91b of the first side plate 91. In other words, if the connection board 83 has a first connector and a second connector, the first connector and the second connector overlap with the second side plate 90. Also, when viewed in the direction of the rotation axis of the photosensitive drum 61, the first connector and the second connector overlap with the recess 91b1 formed on the first outer edge 91b of the first side plate 91.

[0160] With the arrangement of the connection board 83 described above, the connection board 83 can be compactly placed inside the main frame F. In addition, the connection board 83 can be protected by the main frame F.

[0161] Furthermore, in this embodiment, as shown in Figure 13, when viewed in the direction of the rotation axis of the photosensitive drum 61, at least one connector 83a has a length LcL in the longitudinal direction and a length LcS in the short direction perpendicular to the longitudinal direction. Length LcL is longer than length LcS. In this case, the distance Ldc between the connector 83a and the virtual straight line LI is shorter than length LcL. Also, distance Ldc may be shorter than length LcS.

[0162] When viewed in the direction of the rotation axis of the photosensitive drum 61, at least a portion of the wiring board 83b overlaps with the recess 91b1. In this embodiment, when viewed in the direction of the rotation axis of the photosensitive drum 61, the wiring board 83b overlaps with the first side plate 91. Also, when viewed in the direction of the rotation axis of the photosensitive drum 61, the support stay 92 overlaps with the first side plate 91.

[0163] As shown in Figures 14(a) and (b), the inlet 82a of the power supply board 82 is exposed to the outside of the housing 100. A plug for connecting the commercial power supply and the printer 1 is inserted into the inlet 82a. In other words, the inlet 82a is configured to receive AC voltage supplied from the commercial power supply.

[0164] The printer 1 of this embodiment is equipped with a door 20 at the first end 1b1, and the tray unit 50, transfer unit 40, paper feed cassette 31, fuser unit 70, transport path 1c, and double-sided transport path 20a can be accessed from the first end 1b1. The inlet 82a is located on the rear of the housing 100. This prevents the operation of these units from being obstructed by a power cable with a plug inserted into the inlet 82a.

[0165] Furthermore, as shown in Figure 8, in the horizontal direction, the connecting substrate 83 is closer to the second end 1b2 than to the first end b1. Also, when viewed in the direction of the rotation axis of the photosensitive drum 61, the image forming unit IM is positioned on the opposite side of the connecting substrate 83 from the support stay 92. In other words, the support stay 92 is positioned between the image forming unit IM and the connecting substrate 83. Therefore, operation of each unit is not hindered by the support stay 92 or the connecting substrate 83.

[0166] Furthermore, as shown in Figures 12 and 13, the connection board 83 is positioned inside the housing space 92d formed by the first protective part 92b1, the second protective part 92b2, and the mounting part 92a of the support stay 92. Therefore, the connection board 83 is protected by the support stay 92. In addition, the main frame F is grounded. As a result, the effects of radiated noise generated by the connection board 83 communicating with the control board 81 are suppressed by the support stay 92. Since the cables K1 and FFC1 are positioned along the upper rear stay 94, the effects of radiated noise generated from the cables K1 and FFC1 are suppressed by the upper rear stay 94.

[0167] Here, the arrangement of the connection board 83 in the comparative example will be explained using Figure 15. Figure 15 is a diagram showing the relationship between the connection board 83 and the first side plate 91' in the comparative example, and specifically, it is a view of the connection board 83 and the first side plate 91' in the direction of the rotation axis of the photosensitive drum 61. Note that the same reference numerals are used for components that are the same in the comparative example and this embodiment, and detailed explanations are omitted in principle.

[0168] The first side plate 91' of the comparative example has an opening (hole) 91b2 instead of the recess 91b1 of the first side plate 91 in this embodiment. Therefore, the first side plate 91' of the comparative example has a connecting portion 91eR4 that connects the upper extended portion 91eR1 and the lower extended portion 91eR2.

[0169] In the comparative example configuration, it is necessary to ensure the strength of the connection portion 91eR4 in order to prevent deformation (plastic deformation) of the connection portion 91eR4 when a load is applied to the first side plate 91'. In contrast, the first side plate 91 of this embodiment does not have a physical portion corresponding to the connection portion 91eR4, so there is no risk of deformation of the connection portion 91eR4.

[0170] Furthermore, in the comparative example configuration, it is difficult to shorten the distance between the connector 83a and the first outer edge 91b' of the first side plate 91' in order to ensure the strength of the connection portion 91eR4. In contrast, according to the configuration of this embodiment, it is easy to position the connector 83a closer to the virtual straight line LI. [Examples]

[0171] Example 2 will now be described. In Example 2, components similar to those described in the previous example will be denoted by the same reference numerals, and detailed explanations will be omitted in principle.

[0172] Figure 16 is an exploded view illustrating the main frame F' of Example 2. Figure 17 is a perspective view illustrating the main frame F' of Example 2.

[0173] The main frame F of Embodiment 1 has a support stay 92 and an upper rear stay 94, with the support stay 92 and the upper rear stay 94 being connected. On the other hand, the main frame F' of Embodiment 2 has a support stay 192 in which the support stay 92 and the upper rear stay 94 of Embodiment 1 are integrated. In other words, the support stay 192 can be said to be a stay that combines the features of the support stay 92 and the features of the upper rear stay 94 of Embodiment 1.

[0174] In the first embodiment, the support stay 92 was connected to the upper rear stay 94 at the joint W4 (see Figure 10). The support stay 192 has a shape in which the support stay 92 and the upper rear stay 94 are integrated in the portion where the joint W4 is located.

[0175] The support stay 192 is connected to the first side plate 91 and the second side plate 90. At this time, the position of the connection point where the support stay 192 is connected to the first side plate 91 and the second side plate 90 is the same as the position of the connection point where the support stay 92 and the upper rear stay 94 are connected to the first side plate 91 and the second side plate 90 in Embodiment 1.

[0176] The rigidity of the support stay 192 is higher compared to the combination of the support stay 92 and the upper rear stay 94. Therefore, the rigidity of the main frame F' can be increased. [Examples]

[0177] Example 3 will now be described. In Example 3, components similar to those described in the previous example will be denoted by the same reference numerals, and detailed explanations will be omitted in principle.

[0178] Figure 18 is a perspective view illustrating printer 1 of Example 3. Figures 19(a) and (b) are perspective views showing the external appearance of printer 1 of Example 3.

[0179] In Examples 1 and 2, the power supply board 82 was supported by the second side plate 90, but in Example 3, the power supply board 82 is supported by the first side plate 91. In this example as well, as shown in Figures 19(a) and (b), the inlet 82a of the power supply board 82 is exposed to the outside of the housing 100.

[0180] In this embodiment, the printer 1 is equipped with a door 20 at the first end 1b1, and the tray unit 50, transfer unit 40, paper feed cassette 31, fuser unit 70, transport path 1c, and duplex transport path 20a can be accessed from the first end 1b1. In this embodiment, the inlet 82a is located on the rear of the housing 100. This prevents the operation of these units from being obstructed by a power cable with a plug inserted into the inlet 82a.

[0181] Furthermore, since the power supply board 82 is supported by the first side plate 91, the inlet 82a and the connector 83a can be brought closer together. This makes it easier to connect the power cable to the inlet 82a and to connect the various terminals to the connector 83a. [Examples]

[0182] Example 4 will now be described. In Example 4, components similar to those described in the previous example will be denoted by the same reference numerals, and detailed explanations will be omitted in principle.

[0183] Figure 19 is a perspective view illustrating printer 1 of Example 4. Figures 21(a) and (b) are perspective views showing the external appearance of printer 1 of Example 4.

[0184] The connection board 83 in Examples 1, 2, and 3 included at least one electrical element 83c, such as a processing unit (CPU), a memory device (RAM), or a read-only memory (ROM). Furthermore, the connector 83a of the connection board 83 could be connected to, for example, terminals of a local area network communication cable or terminals conforming to the Universal Serial Bus standard. The connection board 83 was configured to generate an image signal based on print instructions (image information) sent from an external device 400 connected via the connector 83a.

[0185] However, the external connection board is not necessarily limited to the connection board 83 described above. In this embodiment, instead of the connection board 83 in embodiments 1, 2, and 3, the connector 82a of the power supply board 82 is exposed to the outside of the housing 100 (outside the printer 1). In other words, the power supply board 82 in this embodiment is just one example of a connection board. In this embodiment, the connection board 83 is supported by the second side plate 90.

[0186] The casing 100 of printer 1 includes an outer casing E3 and a main frame F. The main frame F is included in the device body 1A. The outer casing E3 is at least a portion of the part of printer 1 that is exposed to the outside.

[0187] The relationship between the power supply board 82, the first side plate 91, the second side plate 90, and the support stay 92 in this embodiment can be the same as the relationship between the connection board 83, the first side plate 91, the second side plate 90, and the support stay 92 in embodiments 1, 2, and 3.

[0188] In Examples 1, 2, and 3, the connector 83a was positioned between the first side plate 91 and the second side plate 90 in the axial direction of the photosensitive drum 61. In this embodiment, the position of the connector 82a coincides with the position of the first side plate 91 in the axial direction of the photosensitive drum 61. Allowing such an arrangement improves the design flexibility of the electrical circuit board 82. The connector 82a of the connection board 83 in Examples 1, 2, and 3 may also be arranged as shown in this embodiment.

[0189] Furthermore, the configurations of each embodiment can be combined as needed.

[0190] <Summary> This application discloses at least the following:

[0191] (Composition 1) In an image forming apparatus that forms an image on a recording material, An image forming unit including an image carrier, A housing for the image forming unit, Exterior parts and A first side plate having a first surface that intersects the rotation axis direction of the image carrier, A second side plate having a second surface that intersects the rotation axis direction, wherein the second surface of the second side plate faces the first surface in the rotation axis direction, A stay connected to the first side plate and the second side plate, A housing having the image forming unit positioned between the first side plate and the second side plate in the direction of the rotation axis, A connecting board supported by the stay, comprising a connector exposed to the outside of the housing and a wiring board to which the connector is attached, It has, When viewed in the direction of the rotation axis, the connector overlaps with the recess formed on the outer edge of the first side plate and also overlaps with the second side plate. An image forming apparatus characterized by the following:

[0192] (Configuration 2) With respect to the rotation axis direction, the connecting board is positioned between the first side plate and the second side plate, and the connector is closer to the first side plate than to the second side plate. The image forming apparatus according to configuration 1, characterized in that it is a picture forming apparatus.

[0193] (Composition 3) With respect to the rotation axis direction, when the position midway between the first and second surfaces is defined as the intermediate position, the distance between the intermediate position and the first surface is equal to the distance between the intermediate position and the second surface. With respect to the rotation axis direction, the connector is closer to the first surface than to the intermediate position. The image forming apparatus according to configuration 2, characterized in that...

[0194] (Composition 4) When the connector is designated as the first connector, the connecting board has a second connector. The image forming apparatus according to any one of configurations 1 to 3, characterized in that, when viewed in the direction of the rotation axis, the second connector overlaps with the recess and also overlaps with the second side plate.

[0195] (Composition 5) When viewed in the direction of the rotation axis, at least a portion of the wiring board overlaps with the recess. An image forming apparatus according to any one of configurations 1 to 4, characterized by the above.

[0196] (Composition 6) The stay is connected to the second surface. An image forming apparatus according to any one of configurations 1 to 5, characterized by the above.

[0197] (Composition 7) The outer edge includes a forming portion that forms the recess, and the stay is coupled to the forming portion. An image forming apparatus according to any one of configurations 1 to 6 characterized by the above.

[0198] (Composition 8) The first side plate includes a receiving portion extending in the direction of the rotation axis, The image forming apparatus according to any one of configurations 1 to 7, characterized in that the stay is coupled to the receiving portion.

[0199] (Composition 9) An image forming apparatus according to any one of configurations 1 to 8, characterized in that the stay overlaps with the first side plate when viewed in the direction of the rotation axis.

[0200] (Composition 10) The image forming apparatus according to any one of configurations 1 to 9, characterized in that the wiring board has a mounting surface to which the connector is attached, and the mounting surface extends along the direction of the rotation axis.

[0201] (Composition 11) The image forming apparatus according to configuration 10, characterized in that the mounting surface extends along the vertical direction.

[0202] (Composition 12) Viewed in the direction of the rotation axis, the housing has a first end in the horizontal direction and a second end opposite to the first end. The image forming apparatus according to any one of configurations 1 to 11, characterized in that, in the horizontal direction, the connecting substrate is closer to the second end than to the first end.

[0203] (Composition 13) The fixing device is configured to heat the recording material, The image forming apparatus according to configuration 12, characterized in that, with respect to the horizontal direction, the fixing device is closer to the first end than to the second end.

[0204] (Composition 14) At least a portion of the image forming unit is a movable unit that can move outside the housing, The image forming apparatus according to configuration 12 or 13, characterized in that the first end is provided with an opening through which the moving unit passes.

[0205] (Composition 15) An image forming apparatus according to any one of configurations 1 to 14, characterized by having a first connected substrate connected to the connecting substrate and a second connected substrate connected to the first connected substrate.

[0206] (Composition 16) The image forming apparatus according to configuration 15, characterized in that the direction in which the connecting substrate expands, the direction in which the first connected substrate expands, and the direction in which the second connected substrate expands intersect with each other.

[0207] (Composition 17) With respect to the rotation axis direction, the first connected substrate is positioned between the first side plate and the second side plate. The second connected substrate is supported by the second side plate. The image forming apparatus according to configuration 15 or 16, characterized by the above.

[0208] (Composition 18) The image forming apparatus according to any one of configurations 1 to 17, characterized in that the aforementioned connection board is a communication board.

[0209] (Composition 19) The image forming apparatus according to any one of configurations 1 to 17, characterized in that the aforementioned connection board is a power supply board.

[0210] (Composition 20) The image forming apparatus according to any one of configurations 1 to 19, characterized in that, when viewed in the direction of the rotation axis, the image forming unit is arranged on the opposite side of the connecting substrate from the stay. [Explanation of Symbols]

[0211] 91 1st side plate 91b1 recess 90 Second side plate 92 Support Stay 83 Connection board 83a connector F Mainframe

Claims

1. In an image forming apparatus that forms an image on a recording material, An image forming unit including an image carrier, A housing for the image forming unit, Exterior parts and A first side plate having a first surface that intersects the rotation axis direction of the image carrier, A second side plate having a second surface that intersects the rotation axis direction, wherein the second surface of the second side plate faces the first surface in the rotation axis direction, A stay connected to the first side plate and the second side plate, A housing having the image forming unit positioned between the first side plate and the second side plate in the direction of the rotation axis, A connecting board supported by the stay, comprising a connector exposed to the outside of the housing and a wiring board to which the connector is attached, It has, When viewed in the direction of the rotation axis, the connector overlaps with the recess formed on the outer edge of the first side plate and also overlaps with the second side plate. An image forming apparatus characterized by the following:

2. With respect to the rotation axis direction, the connecting board is positioned between the first side plate and the second side plate, and the connector is closer to the first side plate than to the second side plate. The image forming apparatus according to feature 1.

3. With respect to the rotation axis direction, when the position midway between the first and second surfaces is defined as the intermediate position, the distance between the intermediate position and the first surface is equal to the distance between the intermediate position and the second surface. With respect to the rotation axis direction, the connector is closer to the first surface than to the intermediate position. The image forming apparatus according to feature 2.

4. When the connector is designated as the first connector, the connecting board has a second connector. The image forming apparatus according to claim 1, characterized in that, when viewed in the direction of the rotation axis, the second connector overlaps with the recess and overlaps with the second side plate.

5. When viewed in the direction of the rotation axis, at least a portion of the wiring board overlaps with the recess. The image forming apparatus according to feature 1.

6. The stay is connected to the second surface. The image forming apparatus according to feature 1.

7. The outer edge includes a forming portion that forms the recess, and the stay is coupled to the forming portion. The image forming apparatus according to feature 1.

8. The first side plate includes a receiving portion extending in the direction of the rotation axis, The image forming apparatus according to claim 1, characterized in that the stay is coupled to the receiving portion.

9. The image forming apparatus according to claim 1, characterized in that the stay overlaps with the first side plate when viewed in the direction of the rotation axis.

10. The image forming apparatus according to claim 1, characterized in that the wiring board has a mounting surface to which the connector is attached, and the mounting surface extends along the direction of the rotation axis.

11. The image forming apparatus according to claim 10, characterized in that the mounting surface extends along the vertical direction.

12. Viewed in the direction of the rotation axis, the housing has a first end in the horizontal direction and a second end opposite to the first end. The image forming apparatus according to claim 1, characterized in that, with respect to the horizontal direction, the connecting substrate is closer to the second end than to the first end.

13. The fixing device is configured to heat the recording material, The image forming apparatus according to claim 12, characterized in that, with respect to the horizontal direction, the fixing device is closer to the first end than to the second end.

14. At least a portion of the image forming unit is a movable unit that can move outside the housing, The image forming apparatus according to claim 12, characterized in that the first end is provided with an opening through which the moving unit passes.

15. The image forming apparatus according to claim 1, characterized by having a first connected substrate connected to the connecting substrate and a second connected substrate connected to the first connected substrate.

16. The image forming apparatus according to claim 15, characterized in that the direction in which the connecting substrate expands, the direction in which the first connected substrate expands, and the direction in which the second connected substrate expands intersect with each other.

17. With respect to the rotation axis direction, the first connected substrate is positioned between the first side plate and the second side plate. The second connected substrate is supported by the second side plate. The image forming apparatus according to feature 15.

18. The image forming apparatus according to claim 1, characterized in that the connecting board is a communication board.

19. The image forming apparatus according to claim 1, characterized in that the connection board is a power supply board.

20. The image forming apparatus according to any one of claims 1 to 19, characterized in that, when viewed in the direction of the rotation axis, the image forming unit is arranged on the opposite side of the connecting substrate from the stay.

Images