Image forming device

Abstract

To provide an image forming apparatus that can reduce its size while ensuring the rigidity of an apparatus body.SOLUTION: An image forming apparatus 1 comprises: a left frame 21; a right frame 22 arranged at an interval in the left-and-right direction from the left frame 21; and a first sheet metal member 60 fixed to the left frame 21 and the right frame 22. The first sheet metal member 60 has a body part 61 extending in the left-and-right direction, a left extension part 62 extending downward from a left end in the left-and-right direction of the body part 61 and fixed to a front face of the left frame 21, and a right extension part 63 extending downward from a right end in the left-and-right direction of the body part 61 and fixed to a front face of the right frame 22. The left frame 21 has a step part 21a formed in the fore-and-aft direction on the front face and extending along the vertical direction, and the left frame 21 has a bent part 62a bent frontward along the shape of the step part 21a and corresponding to the step part 21a.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] Conventionally, as disclosed in Patent Document 1, there is known an image forming apparatus having a main body casing, which is an example of a housing having a left side wall and a right side wall arranged opposite each other with a gap therebetween in the left-right direction, and a reinforcing part bridged between the left side wall and the right side wall. The reinforcing part has a first bridge part that is bridged between the front upper ends of the left side wall and the right side wall and is L-shaped in cross section and extends in the left-right direction. The first bridge part has both left and right ends fixed to a part that is approximately L-shaped in side view, which is made up of the upper end of the front edge and the front end of the upper edge of the left side wall and the right side wall. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-63076 A Summary of the Invention [Problem to be solved by the invention]

[0004] Further miniaturization is required for the image forming apparatus described in Patent Document 1. When miniaturizing the main body casing in accordance with the miniaturization of the image forming apparatus, it becomes necessary to reduce the number of reinforcing members reinforcing the main body casing and to change the shape of the reinforcing members to match the shape of the main body casing. However, if the shape or size of the first bridge portion reinforcing the front side of the main body casing is changed in accordance with the miniaturization of the main body casing, it becomes difficult to ensure the rigidity of the main body casing.

[0005] Therefore, the present invention provides an image forming apparatus that can be made compact while ensuring the rigidity of the main body of the apparatus. [Means for solving the problem]

[0006] The image forming apparatus that solves the above problem has the following features.

[0007] That is, the image forming apparatus comprises a first frame, a second frame arranged at a distance from the first frame in a first direction, and a sheet metal member fixed to the first frame and the second frame, the sheet metal member having a main body portion extending in the first direction, a one-side extension portion extending downward from one end of the main body portion in the first direction and fixed to a surface of one end of the first frame in a second direction horizontally perpendicular to the first direction, and an other-side extension portion extending downward from the other end of the main body portion in the first direction and fixed to a surface of one end of the second frame in the second direction, the first frame having a step portion formed in the second direction on the surface of one end in the second direction and extending along the up-down direction, the one-side extension portion being bent to one side in the second direction along the shape of the step portion and having a bent portion corresponding to the step portion.

[0008] In this way, since the one-side extending portion has a bent portion bent to one side in the second direction, the rigidity of the one-side extending portion can be ensured. This ensures the rigidity of the sheet metal member, and therefore makes it possible to miniaturize the device while ensuring the rigidity of the device body.

[0009] The image forming apparatus further comprises a first cam movably supported on the first frame and a second cam movably supported on the second frame, the first frame having a first cam hole for inserting the first cam into its one end surface in the second direction, the second frame having a second cam hole for inserting the second cam into its one end surface in the second direction, a lower end of the one side extension portion being positioned below the first cam hole, and a lower end of the other side extension portion being positioned below the second cam hole.

[0010] This allows the one-side extension portion to ensure the rigidity of the portion of the first frame where the first cam hole is formed, and the other-side extension portion to ensure the rigidity of the portion of the second frame where the second cam hole is formed.

[0011] In addition, the other-side extension portion is positioned at a position that does not overlap with the second cam hole when viewed from the second direction, and the one-side extension portion is positioned at a position that does not overlap with the first cam hole when viewed from the second direction.

[0012] The first frame has a bearing portion that supports a shaft portion of a paper feed roller that transports paper, and a lower end of the one-side extension portion that corresponds to the first frame is located above the bearing portion.

[0013] In addition, a rib extending in the vertical direction is formed at least either below the one-side extension portion of the face of one end of the first frame in the second direction and below the other-side extension portion of the face of one end of the second frame in the second direction.

[0014] In this way, by forming the rib below the extension, it is possible to ensure the rigidity of the portion of the frame where the extension is not located.

[0015] At least one of the one-side extension portion and the other-side extension portion has a bead that bulges in the second direction.

[0016] By forming a bead on the extension portion in this manner, the rigidity of the extension portion can be ensured.

[0017] Further, the width dimension in the first direction of the one-side extending portion is smaller than the width dimension of the other-side extending portion.

[0018] This allows the width of the first frame to be reduced.

[0019] a power supply unit disposed between the first frame and the second frame, the power supply unit having a power supply board on which power supply components are mounted, and a cover for covering the power supply board; The cover is fixed to one of the first frame and the second frame with screws in the axial direction of the bearing portion.

[0020] In this way, since the bearing portion is screwed to one of the first frame and the second frame in the axial direction, the rigidity of the device body can be ensured.

[0021] a power supply unit disposed between the first frame and the second frame, the power supply unit having a power supply board on which power supply components are mounted, and a cover for covering the power supply board; The cover is fixed to both the first frame and the second frame with screws in the axial direction of the bearing portion.

[0022] In this way, since the bearing portion is screwed to both the first frame and the second frame in the axial direction, the rigidity of the device body can be further ensured.

[0023] The cover has a first cover and a second cover, and is provided with an intervening member disposed between one of the first frame and the second frame and the first cover and the second cover, the first cover is screwed together with the intervening member to one of the first frame and the second frame, and the second cover is screwed together with the intervening member to one of the left first frame and the second frame.

[0024] In this way, the first cover and the second cover are screwed to the frame via a common intermediate member, making it possible to reduce the number of parts.

[0025] Further, the lower end of the one-side extending portion and the lower end of the other-side extending portion are disposed at positions overlapping with the cover when viewed from the second direction.

[0026] In this way, by arranging the lower ends of the one-side extension portion and the other-side extension portion at positions overlapping with the cover, it is possible to ensure the rigidity of the device body.

[0027] The image forming apparatus also includes a gear train that drives a driven member, and the first frame supports the gear train.

[0028] As a result, for example, although it is difficult to reduce the size of a gear train in the front-to-rear direction, even if a step occurs between the part where the gear train is arranged and other parts, by providing a bent part in the sheet metal member, it is possible to ensure the strength of the sheet metal member while reducing the size. Effect of the Invention

[0029] According to the present invention, it is possible to reduce the size of the device body while ensuring the rigidity of the device body. [Brief description of the drawings]

[0030] [Figure 1] FIG. 2 is a central cross-sectional view showing the image forming apparatus. [Diagram 2] 1 is a perspective view of a main body of an image forming apparatus as viewed from the front. [Diagram 3] 2 is a perspective view of the main body of the image forming apparatus as viewed from the rear. FIG. [Figure 4] FIG. 2 is a front view showing the main body of the image forming apparatus. [Diagram 5] FIG. 2 is a perspective view showing a first sheet metal member. [Figure 6] FIG. 2 is a front view showing the first sheet metal member. [Figure 7] 11 is a side cross-sectional view of the power supply unit showing the state in which the left end portion of the upper cover is attached to the left frame. FIG. [Figure 8] 11 is a side cross-sectional view of the power supply unit showing a state in which the right end portion of the upper cover is attached to the right frame. FIG. [Figure 9] 8 is a cross-sectional view taken along line AA in FIG. 7. [Figure 10] FIG. 4 is a perspective view showing a state in which a paper feed unit is attached to the left frame. [Figure 11]11 is an enlarged cross-sectional view showing a positioning protrusion and a fixing boss of the left frame in FIG. 10. [Figure 12] FIG. 1 is a front view showing an image forming apparatus. [Figure 13] FIG. 13 is an enlarged cross-sectional view of the line BB in FIG. [Figure 14] 13 is an enlarged cross-sectional view of the line CC in FIG. 12. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0032] [Overall configuration of image forming device] 1 is one embodiment of the image forming apparatus according to the present invention, and includes a device body 2 formed in a substantially rectangular parallelepiped shape, and a top cover 4 disposed at the upper end of the device body 2. The device body 2 includes a left frame 21 which is an example of a first frame, and a right frame 22 which is an example of a second frame (see FIG. 2), which are disposed at a predetermined interval in the left-right direction which is an example of a first direction according to the present invention.

[0033] In the following description, the right side of the paper in Fig. 1 is the "front side" and the left side of the paper in Fig. 1 is the "rear side" based on the state in which image forming apparatus 1 is placed horizontally. Also, the left and right sides are referred to as the "left side" and "right side" when image forming apparatus 1 is viewed from the front side. In other words, the front side of the paper in Fig. 1 is the left side, and the back side of the paper is the right side. Also, the vertically downward direction of image forming apparatus 1 is referred to as the "lower side" and the vertically upward direction is referred to as the "upper side".

[0034] The image forming apparatus 1 includes a plurality of (four) process cartridges 6 arranged in parallel at intervals from each other in the front-to-rear direction within the apparatus main body 2, a power supply unit 9 as an example of a power supply section that supplies power to each section (e.g., a driving source such as a motor) within the image forming apparatus 1, and an LED unit 12 as an example of an exposure member.

[0035] The process cartridge 6 is configured so as to be detachable from the apparatus main body 2 with the top cover 4 in the open position. The process cartridge 6 further includes a photosensitive drum 7 as an example of a photosensitive member, and a developing roller 8.

[0036] The photosensitive drum 7 is formed in a cylindrical shape with the left-right direction being the longitudinal direction, and is provided to be rotatable about its central axis.

[0037] The developing roller 8 extends in the left-right direction and is in contact with the photosensitive drum 7 from the upper front side.

[0038] Moreover, the process cartridge 6 contains toner, which is an example of a developer, above the developing roller 8.

[0039] The LED unit 12 is supported on the lower surface of the top cover 4 so as to be disposed opposite the upper side of the photosensitive drum 7 .

[0040] The toner in the process cartridge 6 is charged positively by friction and carried on the surface of the developing roller 8 as a thin layer of a constant thickness.

[0041] Meanwhile, the surface of the photosensitive drum 7 is uniformly charged by a charger (not shown) and then exposed to light based on predetermined image data by the LED unit 12. As a result, an electrostatic latent image based on the image data is formed on the surface of the photosensitive drum 7. Then, toner carried by the developing roller 8 is supplied to the electrostatic latent image on the surface of the photosensitive drum 7, so that a toner image (developer image) is carried on the surface of the photosensitive drum 7.

[0042] The power supply unit 9 is configured as, for example, a low-voltage power supply unit, and is located above and behind the paper feed tray 13 inside the device body 2. The power supply unit 9 is disposed between the left frame 21 and the right frame 22, and is supported by the left frame 21 and the right frame 22.

[0043] The paper P is stored in a paper feed tray 13 provided at the bottom of the device main body 2, and is transported by various rollers such as the paper feed roller 5 so as to make a U-turn toward the upper rear side, and is fed one sheet at a time between the photosensitive drum 7 and the conveyor belt 14 at a predetermined timing. The paper P is then transported by the conveyor belt 14 from the front side to the rear side so as to sequentially face all the photosensitive drums 7. At this time, the toner image carried on the photosensitive drum 7 is transferred onto the paper P by the transfer bias of a transfer roller 15 arranged opposite the lower side of the photosensitive drum 7 with the conveyor belt 14 in between.

[0044] The paper P is heated and pressed when passing between the heating roller 16 and the pressure roller 17, which are rotated by a driving force. As a result, the toner image is thermally fixed to the paper P.

[0045] Thereafter, the paper sheet P is transported so as to make a U-turn toward the upper front side, and is discharged onto a paper discharge tray 18 provided on the top surface of the device body 2.

[0046] [Device body] As shown in Figure 2, the device main body 2 comprises a left frame 21, a right frame 22 arranged opposite the left frame 21 and spaced apart in the left-right direction, and a reinforcing part 50 installed between the left frame 21 and the right frame 22.

[0047] (Left frame) 2 and 3, the left frame 21 is formed in a generally flat plate shape that is generally rectangular in side view and extends in the front-rear direction. The front-rear direction is an example of a second direction that is perpendicular to the first direction in the horizontal direction. The left frame 21 includes a step portion 21a, a drive unit 23, a first cam hole 24, a bearing portion 25 that supports a shaft portion 5a of the paper feed roller 5 that transports the paper P, and a rib 26.

[0048] The step portion 21a is formed in the front-rear direction on the front surface of the left frame 21, and extends in the up-down direction to approximately the center of the left frame 21 in the up-down direction. The front surface is an example of a surface on one end side in the second direction. The drive unit 23 is configured to input a driving force to the four photosensitive drums 7, and includes a drive cam 23a which is an example of a first cam and extends in the front-rear direction, a gear train 23b (see FIG. 3) which is an example of a drive input member that inputs a driving force to a driven member such as the photosensitive drum 7 by the drive cam 23a, and a compression spring (not shown) which biases the drive cam 23a forward.

[0049] The drive cam 23a is supported by the drive unit 23 so as to be movable in the front-rear direction. The first cam hole 24 is provided in the approximate center in the up-down direction on the front surface of the left frame 21, and is a through hole for inserting the front end portion of the drive cam 23a. The rib 26 extends in the up-down direction, and is formed below the left extension portion 62 (see FIG. 4). The gear train 23b is supported on the left side surface of the left frame 21.

[0050] In this embodiment, the rib 26 is formed below the left extension portion 62, but a rib may also be formed below the right extension portion 63, for example.

[0051] (Right frame) 2, 3 and 4, the right frame 22 is formed in a generally flat plate shape that is generally rectangular in side view and extends in the front-rear direction. The right frame 22 is equipped with a second cam 27 that extends in the front-rear direction and a second cam hole 28 (see FIG. 4). The second cam 27 is supported by the right frame 22 so as to be movable in the front-rear direction. The second cam hole 28 is provided in the approximate center in the up-down direction on the front surface of the right frame 22, and is a through hole for inserting the front end portion of the second cam 27 therethrough.

[0052] (Reinforcement) As shown in Figures 2 and 3, the reinforcing portion 50 comprises a first sheet metal member 60 installed between the upper end of the front end of the left frame 21 and the upper end of the front end of the right frame 22, a second sheet metal member 70 installed between the upper end of the rear end of the left frame 21 and the upper end of the rear end of the right frame 22, a front lower end member 80 installed between the lower end of the front end of the left frame 21 and the lower end of the front end of the right frame 22, a rear lower end member 81 installed between the lower end of the rear end of the left frame 21 and the lower end of the rear end of the right frame 22, and a pipe member 90 installed between a vertical midpoint at the front end of the left frame 21 and a vertical midpoint at the front end of the right frame 22.

[0053] The first sheet metal member 60, the second sheet metal member 70, the front lower end member 80 and the rear lower end member 81 are arranged to connect each end, i.e., the four corners in side view, of the left frame 21 and the right frame 22, which are arranged with a gap in the left-right direction.

[0054] The first sheet metal member 60 and the second sheet metal member 70 are each a member made of sheet metal fixed to the left frame 21 and the right frame 22, and are made of a metal such as stainless steel. The first sheet metal member 60 and the second sheet metal member 70 are formed with a generally L-shaped cross section extending in the left-right direction.

[0055] The left end of the first sheet metal member 60 is fixed to a generally L-shaped portion in side view made up of the upper front edge and front end of the upper edge of the left frame 21. The right end of the first sheet metal member 60 is fixed to a generally L-shaped portion in side view made up of the upper front edge and front end of the upper edge of the right frame 22.

[0056] The first sheet metal member 60 has a main body 61 extending in the left-right direction, a left side extension portion 62 which is a one-side extension portion that extends downward from one end portion (left end portion) of the main body 61 in the left-right direction and is fixed to the surface of one end side in the front-to-rear direction of the left frame 21 (the front surface in this embodiment), a right side extension portion 63 which is the other-side extension portion that extends downward from the other end portion (right end portion) of the main body 61 in the left-right direction and is fixed to the surface of one end side in the front-to-rear direction of the right frame 22 (the front surface in this embodiment), and an upper left mounting portion 64 and an upper right mounting portion 65 which extend rearward from both the left and right ends.

[0057] The main body 61 is a generally rectangular portion extending left and right when viewed from the front. The main body 61 has a rear edge 61a extending rearward from an upper end in the left and right direction (see FIG. 5). The rear edge 61a of the main body 61 can increase the bending rigidity of the main body 61.

[0058] The left side extending portion 62 is a portion corresponding to the left frame 21, and is formed so as to extend to approximately the center in the up-down direction of the front surface of the left frame 21 (see FIG. 4). As shown in FIGS. 5 and 6, the left side extending portion 62 is bent forward along the shape of the step portion 21a, and has a bent portion 62a corresponding to the step portion 21a, a notched portion 62b, a screw fastening portion 62c at the lower end for screwing to the front surface of the left frame 21, an upper through hole 62d, and a lower through hole 62e. The lower end of the left side extending portion 62 is located below the first cam hole 24 of the left frame 21.

[0059] The bent portion 62a is formed in a generally U-shape in cross section so as to conform to the shape of the stepped portion 21a. The left side extending portion 62 is disposed at a position that does not overlap with the first cam hole 24 when viewed from the front-rear direction. The lower end of the left side extending portion 62 is disposed above the bearing portion 25 of the left frame 21. The cutout portion 62b is a portion formed by cutting out the right edge portion on the lower side of the left side extending portion 62 so as not to interfere with the driving cam 23a protruding from the first cam hole 24 on the front surface of the left frame 21. The width dimension of the left side extending portion 62 in the left-right direction is smaller than the width dimension of the right side extending portion 63.

[0060] Fig. 10 is a perspective view showing a state in which the paper feed unit 10 is attached to the left frame 21. Fig. 11 is an enlarged cross-sectional view showing the positioning protrusion 21e and the fixing boss portion 21f of the left frame 21 in Fig. 10. The paper feed unit 10 is provided in the apparatus main body 2 at a position sandwiched vertically between the paper feed tray 13 and the process cartridge 6. The paper feed unit 10 has various rollers (pickup roller, transport roller) such as the above-mentioned paper feed roller 5, and a unit frame 11 that supports these rollers. The unit frame 11 has positioning holes 11a for positioning the paper feed unit 10 in the left frame 21 and screw fastening parts 11b for fixing the paper feed unit 10 to the left frame 21, which are arranged vertically on the front part of one end side (left side) in the left-right direction.

[0061] As shown in FIG. 11, a positioning protrusion 21e and a fixing boss 21f are provided on the front portion of the left frame 21, which are arranged above and below the bearing portion 25 of the left frame 21. The positioning protrusion 21e is formed to protrude forward. The positioning protrusion 21e is inserted into a positioning hole 11a of the unit frame 11 to position the paper feed unit 10 between the paper feed tray 13 and the process cartridge 6 in the apparatus main body 2. The fixing boss 21f is formed to protrude forward. The fixing boss 21f is a screw-fastening boss for screwing the screw-fastening portion 11b of the unit frame 11. The screw-fastening portion 11b is fixed to the fixing boss 21f by a screw member.

[0062] The upper insertion hole 62d is provided at a position corresponding to the positioning protrusion 21e, and is a hole through which the positioning protrusion 21e is inserted. The upper insertion hole 62d is an escape hole for avoiding interference with the positioning protrusion 21e.

[0063] The lower insertion hole 62e is provided at a position corresponding to the fixing boss portion 21f, and is a hole through which the fixing boss portion 21f is inserted. The lower insertion hole 62e is an escape hole for avoiding interference with the fixing boss portion 21f.

[0064] In this way, by providing the upper insertion hole 62d, which serves as an escape hole for the positioning protrusion 21e, and the lower insertion hole 62e, which serves as an escape hole for the fixing boss portion 21f, in the left side extension portion 62 of the first sheet metal member 60, the length dimension in the front-to-rear direction of the device main body 2 can be shortened, and the device can be made more compact.

[0065] The upper left mounting portion 64 and the upper right mounting portion 65 are fixed to the front ends of the upper surfaces of the left frame 21 and the right frame 22, respectively, by screwing.

[0066] The right extension 63 is a portion corresponding to the right frame 22, and is formed so as to extend to approximately the center in the up-down direction of the front surface of the right frame 22. The right extension 63 is formed so as to extend downward from the left extension 62. The right end of the right extension 63 and the right end of the main body 61 are formed so as to be linearly continuous. The right extension 63 has a notch 63a, a bead 63b that bulges in the front-rear direction (forward direction in this embodiment), a screw fastening portion 63c at the lower end for screwing to the front surface of the right frame 22, an upper insertion hole 63d, and a lower insertion hole 63e. The lower end of the right extension 63 is located below the second cam hole 28 of the right frame 22.

[0067] The right side extending portion 63 is disposed at a position that does not overlap with the second cam hole 28 when viewed from the front-rear direction. The cutout portion 63a is a portion formed by cutting out a vertical midway portion of the right edge portion of the right side extending portion 63 so as not to interfere with the second cam 27 protruding from the second cam hole 28 in the front surface of the right frame 22. The bead 63b extends linearly in the vertical direction and is formed adjacent to the right side of the cutout portion 63a.

[0068] Fig. 12 is a front view showing the image forming apparatus 1. Fig. 13 is an enlarged cross-sectional view taken along line BB in Fig. 12. Fig. 14 is an enlarged cross-sectional view taken along line CC in Fig. 12. 13, a front frame 30 extending in the left-right direction is disposed inside the front part of the housing cover 1a that covers the outer peripheral surface of the image forming apparatus 1. The front frame 30 is disposed at one end side (right side) in the left-right direction and has a vertical plate-shaped locking claw part 30a formed to protrude rearward and a screw fastening part 30b for fixing the front frame 30 to the right frame 22.

[0069] As shown in FIG. 13, a frame locking hole 22e and a fixing boss 22f are provided on the front surface of the right frame 22, which are arranged above and below. The frame locking hole 22e is a rectangular hole extending in the vertical direction. The frame locking hole 22e is a hole with which the tip (rear end) of the locking claw 30a of the front frame 30 is locked. The fixing boss 22f is formed to protrude forward. The fixing boss 22f is a screw fastening boss for screwing the screw fastening portion 30b of the front frame 30. The screw fastening portion 30b is fixed to the fixing boss 22f by a screw member.

[0070] As shown in Fig. 14, the upper insertion hole 63d is provided on the right side of the bead 63b in the right extension portion 63. The upper insertion hole 63d is a rectangular hole that is slightly larger than the frame locking hole 22e and extends in the vertical direction. The upper insertion hole 63d is provided at a position corresponding to the frame locking hole 22e, and is a hole through which the locking claw portion 30a is inserted. The upper insertion hole 63d is an escape hole provided so that the locking claw portion 30a engaged with the frame locking hole 22e does not interfere.

[0071] The lower insertion hole 63e is provided at a position corresponding to the fixing boss portion 22f, and is a hole through which the fixing boss portion 22f is inserted. The lower insertion hole 63e is an escape hole for avoiding interference with the fixing boss portion 22f.

[0072] In this way, by providing the upper insertion hole 63d, which serves as an escape hole for the locking claw portion 30a, and the lower insertion hole 63e, which serves as an escape hole for the fixing boss portion 22f, in the right side extension portion 63 of the first sheet metal member 60, the length dimension in the front-to-rear direction of the image forming device 1 can be shortened, and the device can be made more compact.

[0073] In this embodiment, the bead 63b is formed on the right-side extending portion 63, but a bead may also be formed on the left-side extending portion 62, for example.

[0074] As shown in FIG. 4, the lower end of the left extension portion 62 and the lower end of the right extension portion 63 are disposed at positions overlapping with the lower cover 92 and the upper cover 93 when viewed from the front-rear direction.

[0075] [Power supply unit] As shown in Fig. 1, the power supply unit 9 includes a power supply board 91 on which power supply components (not shown) are mounted, a lower cover 92 covering the lower side of the power supply board 91, an upper cover 93 covering the upper side of the power supply board 91, and intervening members 94, 95 (see Figs. 7 to 9). The power supply board 91 is disposed in such a position that a mounting surface 91a for the power supply components faces upward, and is supported by the lower cover 92. The lower cover 92 and the upper cover 93 can be made of, for example, a sheet metal member. The lower cover 92 and the upper cover 93 are examples of the covers of the present invention. The lower cover 92 and the upper cover 93 are members having a fireproof function.

[0076] The lower cover 92 supports the power supply board 91 and includes a lower cover portion 92a that covers the lower side of the power supply board 91 and a rear cover portion 92b that covers the rear side of the power supply board 91. The upper cover 93 includes a first cover portion 93a that covers the front of the power supply board 91 and a second cover portion 93b that covers the rear of the power supply board 91. The lower cover 92 and the upper cover 93 are connected to each other, and the power supply board 91 is entirely covered by the lower cover 92 and the upper cover 93 in the front-rear and up-down directions.

[0077] The power supply board 91, the lower cover 92, and the upper cover 93 each extend in the left-right direction, and an end of a lower cover portion 92a of the lower cover 92 on the right frame 22 side is supported by a support portion (not shown) of the right frame 22. Also, an end of the lower cover portion 92a of the lower cover 92 on the left frame 21 side is supported by a support portion 21d formed on the left frame 21 (see FIG. 9).

[0078] The interposing members 94, 95 are frame-shaped members formed along the cross-sectional shape of the power supply unit 9, and each include elongated holes 94a, 95a extending in the front-rear direction. The interposing members 94, 95 are integrally formed from, for example, resin.

[0079] 7, the interposing member 94 has an outer shape that is substantially the same as the cross-sectional shape of the left end portions of the lower cover 92 and the upper cover 93. The interposing member 94 is disposed between the left frame 21 and the left end portions of the first cover portion 93a and the second cover portion 93b. The long hole 94a faces the right side surface of the left frame 21. The front end side of the long hole 94a faces the opening 21b in the left frame 21, and the rear end side faces the honeycomb-shaped opening 21c in the left frame 21. The lower end portion of the long hole 94a is formed so as to be flush with the mounting surface 91a of the power supply board 91.

[0080] 8, the interposing member 95 has an outer shape substantially the same as the cross-sectional shape of the right end portions of the lower cover 92 and the upper cover 93. The interposing member 95 is disposed between the right frame 22 and the right end portions of the first cover portion 93a and the second cover portion 93b. The long hole 95a faces the left side surface of the right frame 22. The front end side of the long hole 95a faces the opening 22b in the right frame 22, and the rear end side faces the vertical lattice-shaped opening 22c in the right frame 22. The bottom end portion of the long hole 95a is formed so as to be flush with the mounting surface 91a of the power supply board 91.

[0081] A connecting piece 93c is formed on the first cover portion 93a by bending downward an end portion of the first cover portion 93a on the side of the left frame 21. The connecting piece 93c is screwed together with a front end portion of the intermediate member 94 to the left frame 21 in the axial direction of the bearing portion 25 by a screw member.

[0082] A connecting piece 93d is formed on the second cover portion 93b by bending downward an end portion of the second cover portion 93b on the side of the left frame 21. The connecting piece 93d is screwed together with a rear end portion of the intermediate member 94 to the left frame 21 in the axial direction of the bearing portion 25 by a screw member.

[0083] In addition, a connecting piece 93f is formed on the first cover portion 93a by bending downward an end portion of the first cover portion 93a on the side of the right frame 22. The connecting piece 93f is screwed together with a front end portion of the intermediate member 95 to the right frame 22 in the axial direction of the bearing portion 25 by a screw member.

[0084] A connecting piece 93g is formed on the second cover portion 93b by bending downward an end portion of the second cover portion 93b on the side of the right frame 22. The connecting piece 93g is screwed together with a rear end portion of the intermediate member 95 to the right frame 22 in the axial direction of the bearing portion 25 by a screw member.

[0085] In addition, in the image forming apparatus 1 of this embodiment, a so-called electrophotographic image forming apparatus is described as an example, but this is not limited to this, and the present invention may also be applied to a so-called inkjet image forming apparatus.

[0086] [Effects of this embodiment] In this embodiment, the image forming apparatus 1 is configured as described above. In other words, the image forming apparatus 1 comprises a left frame 21, a right frame 22 arranged at a distance from the left frame 21 in the left-right direction, and a first sheet metal member 60 fixed to the left frame 21 and the right frame 22, the first sheet metal member 60 having a main body portion 61 extending in the left-right direction, a left side extension portion 62 extending downward from the left end of the main body portion 61 in the left-right direction and fixed to the front surface of the left frame 21, and a right side extension portion 63 extending downward from the right end of the main body portion 61 in the left-right direction and fixed to the front surface of the right frame 22, the left frame 21 having a step portion 21a formed in the front-rear direction on the front surface and extending along the up-down direction, and the left frame 21 is bent forward following the shape of the step portion 21a and has a bent portion 62a corresponding to the step portion 21a.

[0087] As a result, the left extending portion 62 has the bent portion 62a bent forward, which ensures the rigidity of the left extending portion 62. As a result, the rigidity of the first sheet metal member 60 can be ensured, and the rigidity of the device main body 2 can be ensured while the device can be made compact.

[0088] In addition, the image forming device 1 is provided with a drive cam 23a which is a first cam movably supported on the left frame 21, and a second cam 27 which is movably supported on the right frame 22, the left frame 21 is provided with a first cam hole 24 for inserting the left frame 21 at the front side, the right frame 22 is provided with a second cam hole 28 for inserting the second cam 27 at the front side, the lower end of the left frame 21 is located below the first cam hole 24, and the lower end of the right frame 22 is located below the second cam hole 28.

[0089] This allows the left side extension portion 62 to ensure the rigidity of the portion of the left frame 21 where the first cam hole 24 is formed, and the right side extension portion 63 to ensure the rigidity of the portion of the right frame 22 where the second cam hole 28 is formed.

[0090] Furthermore, the left frame 21 has a bearing portion 25 that supports the shaft portion 5a of the paper feed roller 5 that transports the paper P, and the lower end of the left extension portion 62 corresponding to the left frame 21 is located above the bearing portion 25.

[0091] Further, below the left extension portion 62 on the front surface of the left frame 21, a rib 26 extending in the vertical direction is formed.

[0092] By forming the rib 26 in this manner, the rigidity of the portion of the left frame 21 where the left extension portion 62 is not disposed can be ensured.

[0093] Further, the right extension portion 63 has a bead 63b that bulges forward.

[0094] By forming the bead 63b in the right extension portion 63 in this manner, the rigidity of the right extension portion 63 can be ensured.

[0095] Furthermore, the width dimension in the left-right direction of the left extending portion 62 is smaller than the width dimension of the right extending portion 63 .

[0096] This allows the width dimension of the left extension 62 to be reduced.

[0097] In addition, the image forming apparatus 1 is provided with a power supply unit 9 that is disposed between the left frame 21 and the right frame 22 and has a power supply board 91 on which power supply components are mounted, and an upper cover 93 that covers the power supply board 91, and the upper cover 93 is screwed to both the left frame 21 and the right frame 22 in the axial direction of the bearing portion 25.

[0098] In this way, since the upper cover 93 is fixed to both the left frame 21 and the right frame 22 with screws in the axial direction of the bearing portion 25, the rigidity of the device body 2 can be further ensured.

[0099] In addition, the upper cover 93 has a first cover portion 93a and a second cover portion 93b, and is provided with interposing members 94, 95 arranged between the left frame 21 and the right frame 22 and the first cover portion 93a and the second cover portion 93b, and the first cover portion 93a is screwed to the left frame 21 and the right frame 22 together with the interposing members 94 and 95, and the second cover portion 93b is screwed to the left frame 21 and the right frame 22 together with the interposing members 94 and 95.

[0100] In this way, the first cover and the second cover are screwed to the left frame 21 and the right frame 22 via the common intermediate members 94, 95, so that the number of parts can be reduced.

[0101] Further, the lower end of the left extension portion 62 and the lower end of the right extension portion 63 are disposed at positions overlapping with the lower cover 92 and the upper cover 93 when viewed from the front-rear direction.

[0102] In this way, by arranging the lower ends of the left extension portion 62 and the right extension portion 63 at positions overlapping with the lower cover 92 and the upper cover 93, the rigidity of the device body 2 can be ensured.

[0103] The image forming apparatus 1 also includes a gear train 23b that drives a driven member, and the left frame 21 supports the gear train 23b.

[0104] As a result, for example, although it is difficult to reduce the size of gear train 23b in the front-to-rear direction, even if a step is created between the part where gear train 23b is arranged and other parts, by providing bent portion 62a in first sheet metal member 60, it is possible to ensure the strength of first sheet metal member 60 while reducing the size. [Explanation of symbols]

[0105] 1. Image forming device 2. Device body 21 Left frame (first frame) 21a Step 22 Right frame (2nd frame) 60 First sheet metal member (sheet metal member) 61 Main body 62 Left side extension (one side extension) 63 Right side extension (other side extension)

Claims

1. a first frame; and a second frame disposed at an interval from the first frame in a first direction; a sheet metal member fixed to the first frame and the second frame, the sheet metal member has a main body portion extending in the first direction, a one-side extension portion extending downward from one end of the main body portion in the first direction and fixed to a surface of one end of the first frame in a second direction that is perpendicular to the first direction in a horizontal direction, and an other-side extension portion extending downward from the other end of the main body portion in the first direction and fixed to a surface of one end of the second frame in the second direction, the first frame has a step portion formed by shifting a surface on one end side in the second direction in the second direction, and the step portion has a longitudinal direction extending along a vertical direction perpendicular to the first direction and the second direction; The one-side extension portion is bent to one side in the second direction along the shape of the step portion, and has a bent portion corresponding to the step portion.

2. a first cam movably supported by the first frame and a second cam movably supported by the second frame, the first frame includes a first cam hole for inserting the first cam in a surface on one end side in the second direction, the second frame includes a second cam hole for inserting the second cam in a surface on one end side in the second direction, a lower end of the one-side extension portion is located below the first cam hole, The lower end of the other side extension portion is located below the second cam hole. The image forming apparatus according to claim 1 .

3. The other-side extending portion is disposed at a position not overlapping with the second cam hole when viewed from the second direction, and the one-side extending portion is disposed at a position not overlapping with the first cam hole when viewed from the second direction. The image forming apparatus according to claim 2 .

4. the first frame has a bearing portion that supports a shaft portion of a paper feed roller that transports paper; The lower end of the one-side extension portion corresponding to the first frame is located above the bearing portion. The image forming apparatus according to any one of claims 1 to 3.

5. A rib having a longitudinal direction extending in the up-down direction is formed on at least one of a surface of one end side of the first frame in the second direction below the one-side extending portion and a surface of one end side of the second frame in the second direction below the other-side extending portion. The image forming apparatus according to any one of claims 1 to 4.

6. At least one of the one-side extension portion and the other-side extension portion has a bead that bulges in the second direction. The image forming apparatus according to any one of claims 1 to 5.

7. The width dimension of the one-side extending portion in the first direction is smaller than the width dimension of the other-side extending portion. The image forming apparatus according to claim 1 .

8. a power supply unit that is disposed between the first frame and the second frame and includes a power supply board on which power supply components are mounted, and a cover that covers the power supply board; The cover is fixed to one of the first frame and the second frame with screws in the axial direction of the bearing portion. The image forming apparatus according to claim 4 .

9. a power supply unit that is disposed between the first frame and the second frame and has a power supply board on which power supply components are mounted and a cover that covers the power supply board; The cover is fixed to both the first frame and the second frame with screws in the axial direction of the bearing portion. The image forming apparatus according to claim 4 .

10. The cover includes a first cover and a second cover, an interposition member disposed between one of the first frame and the second frame and the first cover and the second cover, the first cover is fixed to one of the first frame and the second frame together with the intermediate member with a screw; The second cover is fixed to one of the first frame and the second frame together with the intermediate member by screws.

10. The image forming apparatus according to claim 8 or 9.

11. A lower end of the one-side extending portion and a lower end of the other-side extending portion are disposed at positions overlapping with the cover when viewed from the second direction. The image forming apparatus according to any one of claims 8 to 10.

12. A gear train for driving a driven member is provided, The first frame supports the gear train. The image forming apparatus according to claim 1 .

Images