Image forming apparatus

Abstract

To provide an image forming apparatus that can be reduced in weight.SOLUTION: An image forming apparatus comprises: an image forming unit; and a housing that accommodates therein the image forming unit, and that has a first frame including a side plate, a second frame arranged below the first frame, a side face cover, and a top face cover. At least one of the top face cover and the first frame has a first column part. The second frame has a second column part arranged below the first column part. The side face cover has a third column part arranged between the first column part and the second column part in the vertical direction.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus that forms an image on a sheet. [Background technology]

[0002] Conventionally, an image forming apparatus has been proposed in which the structure of the image forming unit is configured as a molded frame, and the molded frame is supported by a metal bottom plate that forms the bottom surface of the image forming apparatus main body excluding the sheet feed cassette unit (see Patent Document 1). This image forming apparatus has three support pillars made of sheet metal erected at three corners of the bottom plate, a box-shaped side plate provided at the remaining corner, and a document reading unit supported by these three support pillars and side plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-84517 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the image forming apparatus described in Patent Document 1, the weight of the three support columns and side plates that constitute the frame of the image forming apparatus is heavy, making the image forming apparatus heavy.

[0005] SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can be made lighter in weight. [Means for solving the problem]

[0006] The present invention is characterized in that an image forming apparatus comprises an image forming unit including an image carrier that carries an image and forms an image on a sheet, and a housing that houses the image forming unit and has an outlet through which sheets on which an image has been formed by the image forming unit are discharged, the housing having a first frame with side plates that support longitudinal ends of the image carrier, a second frame that is arranged below the first frame in the vertical direction, a side cover that forms one side of the housing, and a top cover that forms the top surface of the housing, wherein at least one of the top cover and the first frame has a first support portion, the second frame has a second support portion that is arranged below the first support portion, and the side cover has a third support portion that is arranged between the first support portion and the second support portion in the vertical direction, the third support portion being arranged so as to be able to contact the first support portion and the second support portion in the vertical direction, and being arranged in a position where at least a portion of the third support portion overlaps the first support portion and the second support portion when viewed in the vertical direction. [Effects of the Invention]

[0007] According to the present invention, the image forming apparatus can be made lighter in weight. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1A is a schematic overall view showing a printer according to a first embodiment, and FIG. 1B is a perspective view showing a housing. [Figure 2] (a) is an oblique view showing the pillar and bottom frame attached to the frame body, (b) is an oblique view showing the top cover attached to the frame body, and (c) is an oblique view showing the left cover and right cover attached to the frame body. [Figure 3](a) is a perspective view showing the state where the front cover is attached to the frame body, (b) is a perspective view showing the state where the inner rear cover is attached to the frame body, (c) is a perspective view showing the state where the inner rear cover and inner cover are attached to the frame body, (d) is a perspective view showing the state where the paper output tray is attached to the inner cover, and (e) is a perspective view showing the state where the image reading device is attached to the printer body. [Figure 4] (a) is a perspective view showing the printer body just before the inner cover is attached, (b) is a 4B-4B cross-sectional view of Figure 4(a) and a partially enlarged view thereof, (c) is a perspective view showing the printer body when the inner cover has started to be attached, and (d) is a 4D-4D cross-sectional view of Figure 4(c) and a partially enlarged view thereof showing the printer body when the inner cover has started to be attached. [Figure 5] 5A is a perspective view of the printer body with the inner cover positioned, (b) is a cross-sectional view taken along line 5B-5B of FIG. 5A showing the printer body with the inner cover positioned, and (c) is a partially enlarged view of the printer body with the inner cover fixed with screws. [Figure 6] 6A is a perspective view showing the printer body with the frames and exteriors assembled, and FIG. 6B is a cross-sectional view showing the cross section 6B-6B in FIG. 6A and a partially enlarged view thereof. [Figure 7] 1A is a perspective view showing the printer body immediately before the left and right covers are attached, and FIG. 1B is a perspective view and a partially enlarged view showing the printer body with the left and right covers attached. [Figure 8] 10A is another perspective view showing the printer body 50 immediately before the left and right covers are attached, and FIG. 10B is another perspective view and a partially enlarged view showing the printer body with the left and right covers attached. [Figure 9] FIG. [Figure 10] 1A is a perspective view showing the front cover immediately before being attached to the left cover and the front cover, and FIG. 1B is a perspective view showing the front cover in a state where it has been attached to the left cover and the right cover. [Figure 11]FIG. 1A is a perspective view showing a single-function printer according to a comparative example, and FIG. 1B is a perspective view showing a frame of the single-function printer. [Figure 12] FIG. 1A is a perspective view showing a multifunction printer according to a comparative example, and FIG. 1B is a perspective view showing a frame of the multifunction printer. [Figure 13] FIG. [Figure 14] FIG. 1A is a perspective view showing a housing according to a first modified example of the first embodiment, and FIG. 1B is a perspective view showing a housing according to a second modified example of the first embodiment. [Figure 15] FIG. 10 is a perspective view showing a top cover according to a third modified example of the first embodiment. [Figure 16] FIG. 10 is a perspective view showing a printer according to a fourth modified example of the first embodiment. [Figure 17] 17(a) is a side view showing the left side of a printer according to a fifth modified example of the first embodiment, FIG. 17(b) is an exploded perspective view showing the housing when cut along the 17B-17B cross section in FIG. 17(a), and FIG. 17(c) is a perspective view showing the housing when cut along the 17B-17B cross section in FIG. 17(a). [Figure 18] 18(a) is a perspective view showing a printer according to a sixth modified example of the first embodiment, (b) is a cross-sectional view showing the cross section 18B-18B of the printer according to the first embodiment of FIG. 18(a), and (c) is a cross-sectional view showing the cross section 18B-18B of the printer according to the sixth modified example of the first embodiment of FIG. [Figure 19] 19A is a side view showing the left side of the printer according to the second embodiment, and FIG. 19B is a perspective view showing the housing cut along the 19B-19B cross section in FIG. 19A. [Figure 20] 19(b) is a perspective view showing the printer cut along the 20A-20A cross section in FIG. 19(b), and FIG. 19(b) is a perspective view showing the printer cut along the 20B-20B cross section in FIG. 19(b). [Figure 21] FIG. 4A is a perspective view showing the left cover and the right cover, FIG. 4B is a perspective view showing the housing, and FIG. 4C is another perspective view showing the housing. [Figure 22] FIG. 10 is a perspective view showing a top cover according to a first modified example of the second embodiment and a first modified example of the third embodiment. [Figure 23](a) is a perspective view showing a front cover according to a second modified example of the second embodiment, (b) is a perspective view showing a front cover according to the second modified example of the second embodiment, (c) is a perspective view showing a rear cover according to the second modified example of the second embodiment, and (d) is a perspective view showing a rear cover according to the second modified example. [Figure 24] 24A is a side view showing the left side of the printer according to the third embodiment, and FIG. 24B is a perspective view showing the housing cut along the 24B-24B cross section in FIG. 24A. [Figure 25] (a) is a perspective view showing the printer cut along the 25A-25A cross section in Figure 24(b), (b) is a perspective view showing the printer cut along the 25B-25B cross section in Figure 24(b), and (c) is a perspective view showing the printer cut along the 25C-25C cross section in Figure 24(b). [Figure 26] 1A is an exploded perspective view showing the left cover, the right cover, and the front cover, and FIG. 1B is a perspective view showing the left cover, the right cover, and the front cover assembled together. [Figure 27] FIG. 2A is a perspective view showing the housing, and FIG. 2B is another perspective view showing the housing. [Figure 28] (a) is a side view showing the left side of a printer relating to a second variant of the third embodiment, (b) is an oblique view showing a housing relating to the second variant of the third embodiment, and (c) is another oblique view showing a housing relating to the second variant of the third embodiment. [Figure 29] 10(a) is an exploded perspective view showing a housing according to a second modified example of the third embodiment, and FIG. 10(b) is another perspective view showing the housing according to the second modified example of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] First Embodiment [Overall structure] The printer 100 as an image forming apparatus according to the first embodiment is an electrophotographic laser beam printer. As shown in FIG. 1(a), the printer 100 includes a printer main body 50 as the device main body and an image reading device 70 attached to the top of the printer main body 50. In the following description, the term "sheet" refers to not only plain paper but also special paper such as coated paper, recording materials in special shapes such as envelopes and index paper, and plastic film or cloth for overhead projectors, and a document is also an example of a sheet. The document, which is an example of a sheet, may be blank or may have an image formed on one or both sides.

[0010] 13, the printer main body 50 has an image forming unit 80 that consumes toner, which is a consumable material, to form a toner image on a recording medium P, and a feeding unit 61 that feeds the recording medium P. The printer main body 50 also has a fixing unit 74 that fixes the toner image formed by the image forming unit 80 onto the recording medium, a pair of discharge rollers 68, and a processing circuit 90. The image forming unit 80 is housed inside a frame 1 (see FIG. 1(b)) of a housing 60 of the printer main body 50.

[0011] The image forming section 80 has a scanner unit 42, an electrophotographic process unit 41, and a transfer roller 43 that transfers a toner image formed on a photosensitive drum 44 of the process unit 41 onto a recording medium P. The process unit 41 has the photosensitive drum 44, a cleaning unit 46 arranged around the photosensitive drum 44, a charging roller 47, a developing roller 45, and a storage section 48 that stores toner. The process unit 41 may be fastened to the housing 60 of the printer main body 50 with screws, and may also be removable by a service technician.

[0012] The photosensitive drum 44 serving as an image carrier is a cylindrically shaped photosensitive body, and its end in the longitudinal direction (second direction D2) is supported by the frame 1. The photosensitive drum 44 of this embodiment has a photosensitive layer formed of a negatively charged organic photosensitive material on a drum-shaped base body made of aluminum. The photosensitive drum 44 is driven to rotate in a predetermined direction (direction R in the figure) at a predetermined process speed by a motor.

[0013] The charging roller 47 contacts the photosensitive drum 44 with a predetermined pressure to form a charging portion. A desired charging voltage is applied from a charging high-voltage power supply, thereby uniformly charging the surface of the photosensitive drum 44 to a predetermined potential. In this embodiment, the photosensitive drum 44 is negatively charged by the charging roller 47.

[0014] The scanner unit 42 scans and exposes the surface of the photosensitive drum 44 by irradiating the photosensitive drum 44 with laser light corresponding to image information input from an external device using a polygon mirror. This exposure forms an electrostatic latent image corresponding to the image information on the surface of the photosensitive drum 44. Note that the scanner unit 42 is not limited to a laser scanner device, and may, for example, be an LED exposure device having an LED array in which a plurality of LEDs are arranged along the longitudinal direction of the photosensitive drum 44.

[0015] The developing roller 45 is rotatably supported by the container 48. The developing roller 45 is disposed to face the photosensitive drum 44. The container 48 may be provided with a supply roller that applies the toner contained in the container 48 to the surface of the developing roller 45.

[0016] The process unit 41 of this embodiment uses a contact development method. That is, a toner layer carried on the development roller 45 comes into contact with the photosensitive drum 44 in a development section (development area) where the photosensitive drum 44 and the development roller 45 face each other. A development voltage is applied to the development roller 45 by a development high-voltage power supply. Under the development voltage, the toner carried on the development roller 45 is transferred from the development roller 45 to the drum surface in accordance with the potential distribution on the surface of the photosensitive drum 44, thereby developing the electrostatic latent image into a toner image.

[0017] The toner of this embodiment does not contain a magnetic component, and is a so-called non-magnetic one-component developer in which the toner is carried on the developing roller 45 mainly by intermolecular forces and electrostatic forces (image forces). However, a one-component developer containing a magnetic component may also be used. In addition to toner particles, a one-component developer may also contain additives (e.g., wax or silica particles) for adjusting the fluidity and charging performance of the toner. A two-component developer composed of non-magnetic toner and a magnetic carrier may also be used as the developer. When a magnetic developer is used, a cylindrical developing sleeve with a magnet disposed inside is used as the developer carrier, for example.

[0018] The fixing unit 74 is a thermal fixing type that fixes an image by heating and melting toner on the recording medium. The fixing unit 74 includes a heating roller 71 that incorporates a fixing heater 73, and a pressure roller 72 that presses against the heating roller 71. The feeding unit 61 has a cassette 62 on which the recording medium P is loaded, a pickup roller 63, and a pair of separation rollers 64. The cassette 62 can be pulled out from the housing 60 of the printer main body 50.

[0019] The processing circuit 90 has multiple electronic components 91, 92, and 93 arranged on a board. For example, the electronic component 91 may be a processor, the electronic component 92 may be a memory, and the electronic component 93 may be an input / output device. The input / output device may include a communication interface. When a job instructing image formation is input to the printer main body 50, an image formation process based on input image data received from, for example, an external computer, is initiated. The processing circuit 90 operates as a controller for controlling the image formation process.

[0020] Next, the image forming process of the printer main body 50 will be described. When the image forming process starts, the scanner unit 42 irradiates the photosensitive drum 44 with laser light based on input image information. At this time, the photosensitive drum 44 is pre-charged by the charging roller 47, and an electrostatic latent image is formed on the photosensitive drum 44 by irradiating it with laser light. Thereafter, the electrostatic latent image is developed by the developing roller 45, and a toner image is formed on the photosensitive drum 44 as an image.

[0021] In parallel with the above-described image forming process, a pickup roller 63 of a feeding unit 61 feeds out recording media P supported in a cassette 62. The recording media P are separated one by one by a separation roller pair 64 and conveyed to the separation roller pair 64. Then, the recording media P are conveyed by the separation roller pair 64 toward a transfer nip N formed by a transfer roller 43 and a photosensitive drum 44.

[0022] A transfer voltage is applied to the transfer roller 43 from a transfer high-voltage power supply, and the toner image carried on the photosensitive drum 44 is transferred to the recording medium P being transported by the separation roller pair 64. The recording medium P with the transferred toner image is transported to the fixing unit 74, where the toner image is heated and pressurized as it passes through the nip between the heating roller 71 and pressure roller 72 of the fixing unit 74. This melts the toner particles and then solidifies them, thereby fixing the toner image to the recording medium P. The recording medium P that has passed through the fixing unit 74 is discharged from the discharge port 81 to the outside of the printer main body 50 (outside the machine) by the discharge roller pair 68, and is stacked on the discharge tray 16. After the toner image is transferred to the recording medium P, any toner remaining on the photosensitive drum 44 is cleaned by the cleaning unit 46.

[0023] It should be noted that, although the printer main body 50 of the present embodiment is configured to be capable of forming an image on only one side of the recording medium P, the present invention is not limited to this. For example, the printer main body 50 may be provided with a double-sided conveying path for reversing the recording medium P with an image formed on the first side thereof, so that the printer main body 50 can form images on both sides of the recording medium P.

[0024] The printer main body 50 has a housing 60 (see FIG. 1(a)) that has multiple frames that form the structure of the printer main body 50 and multiple covers that form the exterior of the printer main body 50. As shown in FIGS. 1(b) to 3(e), the housing 60 has a frame 1, a bottom frame 4 fixed to the frame 1, pillars 17 fixed to the frame 1, a top cover 10, a left cover 11, a right cover 12, and a front cover 13. The housing 60 also has an inner rear cover 14, an inner cover 15, an ejection tray 16, and a rear cover (not shown). More specifically, the frame of the housing 60 is made up of the frame 1, the bottom frame 4, and the pillars 17. The frame 1 is made up of a metal material such as sheet metal, and the bottom frame 4 and the pillars 17 are made up of a resin material. The exterior of the housing 60 is made up of a top cover 10, a left cover 11, a right cover 12, a front cover 13, an inner rear cover 14, an inner cover 15, an output tray 16, and a rear cover (not shown), all of which are made of resin material.

[0025] [Printer frame and exterior assembly] Next, the assembly sequence of the frame and exterior of the printer 100 will be described using Figures 2(a) to 3(e). First, as shown in Figure 2(a), the printer 100 is assumed to be installed on a horizontal surface. With respect to the frame 1, the front cover 13 is referred to as the front, the rear cover as the rear, the left cover 11 as the left, the right cover 12 as the right, and the top cover 10 as the top. In the following, the direction from the rear to the front is referred to as the first direction D1, and the directions from left to right and from right to left, i.e., the width direction of the printer 100, are referred to as the second direction D2. These first direction D1 and second direction D2 are parallel to the horizontal direction. The first direction D1 is the direction along the sheet discharge direction DD (see Figure 1(a)) by the discharge roller pair 68. The directions from top to bottom and from bottom to top, i.e., the up-down direction of the printer 100, are referred to as the vertical direction D3. The second direction D2, which is the longitudinal direction of the photosensitive drum 44, is a direction orthogonal to the first direction D1 and the vertical direction D3. The vertical direction D3 perpendicularly intersects with the horizontal plane formed by the first direction D1 and the second direction D2.

[0026] The worker attaches the bottom frame 4 and pillars 17 to the frame body 1. The frame body 1 and the pillars 17 constitute a first frame 40, and the bottom frame 4, which serves as a second frame, is configured separately from the first frame 40. The frame body 1 has a side plate 1a. The pillars 17, which serve as extension members, are fixed to the upper part of the side plate 1a and extend in the first direction D1. The bottom frame 4 is fixed to the lower part of the side plate 1a via a molded frame and extends in the first direction D1. The bottom frame 4 may support the frame body 1 from below in the vertical direction D3. The length h2 of the bottom frame 4 in the vertical direction D3 is shorter than the length h1 of the side plate 1a in the vertical direction D3. The pillars 17 and the bottom frame 4 extend downstream of the side plate 1a in the first direction D1 and the discharge direction DD.

[0027] 2(a) and 9, the bottom frame 4 is formed in a generally U-shape when viewed from downstream to upstream in the first direction D1. The bottom frame 4 is disposed on the left side of the housing 60 and has a left wall 4a extending in the vertical direction D3, a right wall 4b disposed on the right side of the housing 60 and extending in the vertical direction D3, and a connecting portion 4c extending in the second direction D2 to connect the left wall 4a and the right wall 4b. The left wall 4a is provided with a second support column 32 (described later) extending upward from the left wall 4a. The right wall 4b is provided with a fifth support column 33 (described later) extending upward from the right wall 4b.

[0028] Next, as shown in Fig. 2(b), the worker attaches the top cover 10 to the frame 1 and the pillars 17. Then, as shown in Fig. 2(c), the worker attaches the left cover 11 and the right cover 12 to the frame 1, and further, as shown in Fig. 3(a), the worker attaches the front cover 13 to the front side of the printer 100.

[0029] Next, the worker attaches the inner rear cover 14 to the frame 1 as shown in FIG. 3(b). The inner rear cover 14 is a member having a discharge port 81 (see FIG. 13) formed therein and is provided near the pair of discharge rollers 68. Furthermore, the worker attaches the inner cover 15 to the frame 1 as shown in FIG. 3(c), and then attaches the discharge tray 16 to the inner cover 15 so that it can rotate relative to the inner cover 15 as shown in FIG. 3(d). The inner cover 15 is a member having a supply port 18 and covers the image forming unit 80 from above. The reason why the discharge tray 16 is configured to be rotatable is to allow the user to access the toner supply port 18 provided in the inner cover 15 when replenishing toner. In other words, the inner cover 15 with the supply port 18 is located below the discharge tray 16 when it is closed. The user can easily replenishing toner to the developing container of the printer 100 by attaching a replenishing pack containing toner to the supply port 18 and performing a toner replenishing operation. Finally, as shown in FIG. 3(e), the worker attaches the image reading device 70 to the top of the printer body 50, completing the assembly of the frame and exterior of the printer 100.

[0030] Furthermore, the image reading device 70 is rotatable relative to the printer body 50, and by rotating the image reading device 70, the user can access the sheets discharged onto the discharge tray 16. Furthermore, by rotating the discharge tray 16 in this state, the user can access the toner supply port 18. The image reading device 70 and the discharge tray 16 are configured to be rotatable enough to allow a supply pack to be attached to the supply port 18.

[0031] Next, a method for attaching the inner cover 15 and the discharge tray 16 will be described in more detail with reference to FIGS. 4(a) through 6(b). FIG. 4(a) is a perspective view showing the printer body 50 immediately before the inner cover 15 is attached, and FIG. 4(b) is a cross-sectional view taken along line 4B-4B of FIG. 4(a) and a partially enlarged view thereof, showing the printer body 50 immediately before the inner cover 15 is attached. FIG. 4(c) is a perspective view showing the printer body 50 when the inner cover 15 has begun to be attached, and FIG. 4(d) is a cross-sectional view taken along line 4D-4D of FIG. 4(c) and a partially enlarged view thereof, showing the printer body 50 when the inner cover 15 has begun to be attached. FIG. 5(a) is a perspective view showing the printer body 50 with the inner cover 15 positioned, and FIG. 5(b) is a cross-sectional view taken along line 5B-5B of FIG. 5(a) and a partially enlarged view thereof, showing the printer body 50 with the inner cover 15 positioned. Fig. 5(c) is a partially enlarged view of the printer main body 50 with the inner cover 15 fixed with the screws 24. Note that Figs. 4(a) to 6(b) show the printer main body 50 with the inner rear cover 14 already attached.

[0032] 4(a) and 4(b), the inner cover 15 is provided with positioning holes 19, and the front cover 13 is provided with claws 20 that can engage with the positioning holes 19. The operator inserts the inner cover 15 into the printer body 50 so that the claws 20 engage with the positioning holes 19.

[0033] 4(c) and 4(d), the inner cover 15 is provided with a positioning boss 21 and a hole 25, and the inner rear cover 14 is provided with a positioning hole 22 that can engage with the positioning boss 21. As shown in FIGS. 4(c) to 5(b), the operator inserts the claw 20 into the positioning hole 19 of the inner cover 15 on the front side of the printer body 50. Because the claw 20 extends rearward from the rear side of the front cover 13, the engagement of the claw 20 with the positioning hole 19 determines the position of the inner cover 15 in the vertical direction D3.

[0034] In this state, the rear part of the inner cover 15 is swung downward, whereby the positioning boss 21 is inserted into the positioning hole 22. Because the positioning boss 21 extends downward, the position of the inner cover 15 in the front-to-rear direction is determined by the engagement between the positioning boss 21 and the positioning hole 22.

[0035] Screw holes 23 are provided in the frame 1 below the inner cover 15 engaged with the front cover 13 and the inner rear cover 14. As shown in FIG. 5(c), the inner cover 15 is fastened to the frame 1 by screws 24 inserted into the screw holes 23. The discharge tray 16 may be fixed to a member other than the frame 1.

[0036] Fig. 6(a) is a perspective view showing the printer main body 50 with the frames and exteriors assembled. Fig. 6(b) is a cross-sectional view showing the 6B-6B cross section of Fig. 6(a) and a partially enlarged view thereof. As shown in Figs. 6(a) and 6(b), the ejection tray 16 is configured to be rotatable about the shaft 26 by inserting the shaft 26 provided on the ejection tray 16 into the hole 25 of the inner cover 15. The inner cover 15 also has a curved portion 27 recessed downward to avoid the rotational path of the ejection tray 16.

[0037] The screws 24 fasten the inner cover 15 to the frame 1 near the curved portion 27. The screws 24 are located behind the discharge tray 16 when the printer 100 is open. Therefore, when the discharge tray 16 is open, the screws 24 are hidden by the discharge tray 16 and cannot be seen from the front of the printer 100. When the discharge tray 16 is closed, the screws 24 are located below the discharge tray 16, and the discharge tray 16 is not exposed to the outside. By arranging the screws 24 in this manner, the screws 24 are difficult for the user to see regardless of the position of the discharge tray 16, thereby improving the appearance of the printer 100.

[0038] [Support structure of the housing according to the first embodiment] Next, the support structure of the housing 60 of the printer main body 50 will be described using Figures 7(a) to 10(b). Figure 7(a) is a perspective view showing the printer main body 50 immediately before the left cover 11 and right cover 12 are attached, and Figure 7(b) is a perspective view and partial enlarged view showing the printer main body 50 in a state where the left cover 11 and right cover 12 are attached. Figure 8(a) is another perspective view showing the printer main body 50 immediately before the left cover 11 and right cover 12 are attached, and Figure 8(b) is another perspective view and partial enlarged view showing the printer main body 50 in a state where the left cover 11 and right cover 12 are attached. Figure 9 is a schematic front view showing the housing 60.

[0039] As shown in FIGS. 7(a) and 7(b) and 9, the left cover 11, which serves as a side cover and a first side cover, extends along the first direction D1 and the vertical direction D3 and constitutes one side of the housing 60. In other words, the left cover 11 extends along the ejection direction DD (see FIG. 1(a)) and the vertical direction D3 and covers the side plate 1a. The top cover 10 constitutes the top surface of the housing 60. As described above, in the left front portion of the housing 60, the pillar 17 and the bottom frame 4 extend downstream in the first direction D1 from the side plate 1a, and a space is formed in the area surrounded by the pillar 17, the side plate 1a, and the bottom frame 4. In this embodiment, the left cover 11 is provided with a third support portion 30 so as to enter the space. The support structure of the left front portion of the housing 60 will be described in detail below.

[0040] A portion of each of the top cover 10 and the pillar 17 constitutes a first support column 34. The pillar 17 is arranged so as to be able to come into contact with a third support column 30, which will be described later. The bottom frame 4 has a second support column 32 that is arranged below the first support column 34 and is arranged at a position where at least a portion of the second support column 32 overlaps the first support column 34 when viewed in the vertical direction D3. The second support column 32 is arranged directly below the pillar 17. The left cover 11 has a third support column 30 that protrudes toward the inside of the printer body 50 in the second direction D2, and the third support column 30 is arranged between the first support column 34 and the second support column 32 in the vertical direction D3. The third support column 30 is arranged so as to be able to come into contact with the first support column 34 and the second support column 32 and is arranged at a position where at least a portion of the third support column 30 overlaps the first support column 34 and the second support column 32 when viewed in the vertical direction D3.

[0041] As shown in FIG. 9 , the left wall 4a of the bottom frame 4 extends in the vertical direction D3, and the second support column 32 integrally formed with the left wall 4a is provided so as to be able to come into contact with the third support column 30. The right wall 4b of the bottom frame 4 extends in the vertical direction D3, and the fifth support column 33 integrally formed with the right wall 4b is provided so as to be able to come into contact with the sixth support column 31 (described later). By configuring the bottom frame 4 in this manner, when a load acts on the second support column 32 from above in the vertical direction D3, the left wall 4a can bear the load. When a load acts on the fifth support column 33 from above in the vertical direction D3, the right wall 4b can bear the load. Furthermore, since the left wall 4a and the right wall 4b of the bottom frame 4 are connected by the connecting portion 4c, the bottom frame 4 has high rigidity against forces from the second direction D2.

[0042] In addition, in the vertical direction D3, there may be some gap between the first support column 34 and the third support column 30 and between the second support column 32 and the third support column 30 for assembly purposes, or there may be no gap at all. In either case, it is sufficient that the first support column 34 and the third support column 30 or the second support column 32 and the third support column 30 are arranged so that they can come into contact with each other when an external force is applied to the printer body 50. Furthermore, the first support column 34, the second support column 32, and the third support column 30 are arranged so as to overlap the side plate 1a in the second direction D2. This allows the housing 60 to be configured compactly in the second direction D2.

[0043] In this way, by attaching the left cover 11 to the frame 1, the first support column 34, the second support column 32, and the third support column 30 form a support structure PL1 that is connected in the vertical direction D3. The support structure PL1 is located at one end in the second direction D2 and forms part of the structure of the printer body 50, and when an external force acts on the printer body 50, it can withstand this external force, particularly in the vertical direction D3. For example, a load acting from above on the first support column 34 can be borne by the second support column 32 via the third support column 30.

[0044] 8(a) and 8(b), the right cover 12, which serves as a second side cover, extends in the first direction D1 and the vertical direction D3 and constitutes the side of the housing 60 opposite to the side (the side of the left cover 11). In other words, the right cover 12 extends in the ejection direction DD (see FIG. 1(a)) and the vertical direction D3. In the right front portion of the housing 60, the top cover 10 and the bottom frame 4 extend downstream in the first direction D1 from the side plate 1a, and a space is formed in the area surrounded by the top cover 10, the right side plate 1b, and the bottom frame 4. In this embodiment, a sixth support portion 31 is provided on the right cover 12 so as to enter the space. The support structure of the right front portion of the housing 60 will be described in detail below.

[0045] A portion of the top cover 10 constitutes the fourth support column 35. The bottom frame 4 has a fifth support column 33 that is disposed below the fourth support column 35 and is located at a position where at least a portion of the fifth support column 33 overlaps with the fourth support column 35 when viewed in the vertical direction D3. The right cover 12 has a sixth support column 31 that protrudes toward the inside of the printer body 50 in the second direction D2, and the sixth support column 31 is located between the fourth support column 35 and the fifth support column 33 in the vertical direction D3. The sixth support column 31 is located so as to be able to come into contact with the fourth support column 35 and the fifth support column 33, and is located at a position where at least a portion of the sixth support column 31 overlaps with the fourth support column 35 and the fifth support column 33 when viewed in the vertical direction D3.

[0046] In addition, in the vertical direction D3, there may or may not be a small gap between the fourth support column 35 and the sixth support column 31 and between the fifth support column 33 and the sixth support column 31 for assembly purposes. In either case, it is sufficient that the fourth support column 35 and the sixth support column 31 or the fifth support column 33 and the sixth support column 31 are able to come into contact with each other when an external force is applied to the printer body 50.

[0047] In this way, by attaching the right cover 12 to the frame 1, the fourth support column 35, the fifth support column 33, and the sixth support column 31 form a support structure PL2 that is connected in the vertical direction D3. The support structure PL2 is located on the other end side in the second direction D2 and forms part of the structure of the printer body 50, and when an external force acts on the printer body 50, it can withstand this external force, particularly in the vertical direction D3. For example, a load acting from above on the fourth support column 35 can be withstood by the fifth support column 33 via the sixth support column 31.

[0048] Fig. 10(a) is a perspective view showing the front cover 13 immediately before being attached to the left cover 11 and the right cover 12, and Fig. 10(b) is a perspective view showing the front cover 13 in a state where it has been attached to the left cover 11 and the right cover 12. As shown in Figs. 10(a) and 10(b), the front cover 13, which serves as a third side cover, extends along the second direction D2 and the vertical direction D3, and forms the exterior of the front side of the printer main body 50. The front cover 13 is attached to the left cover 11 and the right cover 12 by a plurality of claws (not shown), connecting the left cover 11 and the right cover 12.

[0049] The front cover 13 has a first engagement portion 13a that can engage with the third support column 30 of the left cover 11 and a second engagement portion 13b that can engage with the sixth support column 31 of the right cover 12. More specifically, the first engagement portion 13a is provided so as to be able to come into contact with the right side surface of the third support column 30, and the second engagement portion 13b is provided so as to be able to come into contact with the left side surface of the sixth support column 31. There may be a small gap between the first engagement portion 13a and the third support column 30, and there may be no gap between the second engagement portion 13b and the sixth support column 31. In either case, it is sufficient that the first engagement portion 13a and the third support column 30, or the second engagement portion 13b and the sixth support column 31, can come into contact with each other when an external force acts on the printer body 50 from the second direction D2. The first engagement portion 13a and the second engagement portion 13b are arranged at approximately the same height in the vertical direction D3. The front cover 13, which engages with the left cover 11 and the right cover 12, forms a support structure PL3 extending in the second direction D2. The support structure PL3 forms part of the structure of the printer body 50, and when an external force acts on the printer body 50, it can withstand this external force, particularly in the second direction D2. In addition, a plurality of ribs 13c extending in the second direction D2 are formed on the rear side of the front cover 13, improving rigidity against loads from the second direction D2.

[0050] [Comparative Example] Next, printers 100A and 100B according to comparative examples will be described with reference to Figs. 11(a) to 12(b). Fig. 11(a) is a perspective view showing a printer 100A that does not have an image reading device and is specialized for image forming functions (hereinafter referred to as a single-function printer). Fig. 11(b) is a perspective view showing a frame 110A of the single-function printer 100A. Fig. 12(a) is a perspective view showing a printer 100B that has an image reading function in addition to an image forming function (hereinafter referred to as a multi-function printer). Fig. 12(b) is a perspective view showing the frame 110B of the multi-function printer 100B.

[0051] In recent years, in order to maximize the efficiency of product development, it has become common to realize a multifunction printer by mounting an image reading device on top of a single function printer. For example, the multifunction printer 100B shown in Fig. 12(a) is a multifunction printer in which an image reading device 103 is added to the top of the single function printer 100A shown in Fig. 11(a). The image reading device 103 can read an image of a document.

[0052] As shown in FIG. 11(b), the frame 110A of the single-function printer 100A is composed of a frame 101. The image reading device 103 of the multi-function printer 100B is larger than that of the single-function printer 100A. Therefore, the frame 110B of the multi-function printer 100B has the frame 101 and an extension frame 105 that is additionally fixed to the frame 101. The extension frame 105 is made of a metal material and extends in the second direction D2 and the vertical direction D3. This ensures the rigidity of the multi-function printer 100B so that it can withstand impacts that may occur if the product is dropped during transportation, and the extension frame 105 forms the structural body of the multi-function printer 100B.

[0053] However, the extension frame 105 has approximately the same height as the side plates 101a and 101b of the frame 1, and is approximately the same size as the product size of the multifunction printer 100B in the second direction D2. This makes the extension frame 105 heavy, which increases the weight and cost of the multifunction printer 100B.

[0054] [Advantages of the first embodiment] 7(a) to 9, in the first embodiment, the left cover 11 is provided with a third support column 30, which constitutes part of the support column structure PL1. The right cover 12 is provided with a sixth support column 31, which constitutes part of the support column structure PL2. Furthermore, the front cover 13 engages with the third support column 30 and the sixth support column 31 to constitute a support column structure PL3 extending in the width direction. In this manner, in this embodiment, the left cover 11, right cover 12, and front cover 13, which are part of the exterior of the housing 60 of the printer 100, are utilized as part of the support column structures PL1, PL2, and PL3, which are the structural components of the printer 100.

[0055] Therefore, for example, when applying the frame body 1 for a single-function printer to a multi-function printer, the pillars 17 and bottom frame 4, which are frame members added to the frame body 1, can be made smaller. Also, the left cover 11, right cover 12, and front cover 13, which are part of the exterior of the housing 60 of the printer 100, are made of a resin material and are therefore relatively lightweight. This allows the printer 100 to be made lighter and less expensive while maintaining its rigidity. The third support pillar 30 of the left cover 11 and the sixth support pillar 31 of the right cover 12 each have a size of at least several centimeters in the vertical direction D3.

[0056] In the above-described embodiment, the third support column 30 provided on the left cover 11 constitutes part of the support column structure PL1, and the sixth support column 31 provided on the right cover 12 constitutes part of the support column structure PL2. However, this is not limiting. Alternatively, the third support column 30 provided on the left cover 11 may constitute part of the support column structure PL1, while the sixth support column 31 is not provided on the right cover 12, and the right cover 12 does not constitute part of the support column structure PL2. Alternatively, the sixth support column 31 provided on the right cover 12 may constitute part of the support column structure PL2, while the third support column 30 is not provided on the left cover 11, and the left cover 11 does not constitute part of the support column structure PL1.

[0057] <Modification of the first embodiment> Next, first to sixth modified examples of this embodiment will be described with reference to FIGS. 14(a) to 18(c). FIG. 14(a) is a perspective view showing a housing 60A according to a first modified example. FIG. 14(b) is a perspective view showing a housing 60B according to a second modified example. FIG. 15 is a perspective view showing a top cover 10C according to a third modified example. FIG. 16 is a perspective view showing a printer 100D according to a fourth modified example. FIG. 17(a) is a side view showing the left side of a printer 100E according to a fifth modified example. FIG. 17(b) is an exploded perspective view showing the housing 60E when cut along the 17B-17B cross section of FIG. 17(a), and FIG. 17(c) is a perspective view showing the housing 60E when cut along the 17B-17B cross section of FIG. 17(a). FIG. 18(a) is a perspective view showing the printers 100 and 100F. Figure 18(b) is a cross-sectional view showing the 18B-18B section of the printer 100 in Figure 18(a), and Figure 18(c) is a cross-sectional view showing the 18C-18C section of the printer 100F according to the sixth modified example in Figure 18(a).

[0058] In the above-described embodiment, the first support column 34 on the left front side of the housing 60 is formed from a part of the top cover 10 and a part of the pillar 17, and the fourth support column 35 on the right front side of the housing 60 is formed from a part of the top cover 10. In other words, the housing 60 has the pillar 17 only on the left side in the second direction D2.

[0059] <First Modification of the First Embodiment> 14(a), the housing 60A according to the first modification has pillars 17 at both ends in the second direction D2. That is, the first support column 34 and the fourth support column 35 are formed from a part of the pillar 17 and a part of the top cover 10, respectively.

[0060] <Second Modification of the First Embodiment> 14(b), the housing 60B according to the second modification has a pillar 17 only at the right end in the second direction D2. That is, the first support column 34 is formed from a part of the top cover 10, and the fourth support column 35 is formed from a part of the top cover 10 and a part of the pillar 17.

[0061] <Third Modification of the First Embodiment> 15, the top cover 10C according to the third modification has a first support pillar 34 and a second support pillar 35 at both ends in the second direction D2. The first support pillar 34 and the second support pillar 35 extend downward from the top surface of the top cover 10C and do not include pillars 17. In other words, the top cover 10C is provided so as to be able to come into contact with the third support pillar 30 and the sixth support pillar 31.

[0062] In this way, the first support column 34 and the fourth support column 35 may or may not include the pillar 17. Furthermore, the first support column 34 and the fourth support column 35 may or may not include the top cover 10C. In other words, at least one of the first frame 40 including the frame body 1 and the pillar 17 and the top cover 10 constitutes the first support column 34 and the fourth support column 35, respectively.

[0063] <Fourth Modification of the First Embodiment> Furthermore, in the above-described embodiment, the printer 100 having the image reading device 70 above the printer main body 50 has been described as an example, but the present invention is not limited to this. For example, as shown in Fig. 16, a printer 100D according to a fourth modification includes an image forming unit 80 but does not include the image reading device 70 shown in Fig. 1(a). In other words, the present invention may be applied not only to multifunction printers that include the image reading device 70, but also to single-function printers that do not include the image reading device 70.

[0064] <Fifth Modification of the First Embodiment> 17(a) to 17(c), the third support column 30 and the sixth support column 31 may be formed on the front cover 13E. That is, as shown in FIGS. 17(b) and 17(c), when the front cover 13E is attached to the left cover 11 and the right cover 12, the third support column 30 of the front cover 13E is disposed between the first support column 34 and the second support column 32 in the vertical direction D3. Furthermore, the sixth support column 31 of the front cover 13E is disposed between the fourth support column 35 and the fifth support column 33 in the vertical direction D3. As a result, the third support column 30 and the sixth support column 31 of the front cover 13E constitute part of the support column structures PL1 and PL2, respectively.

[0065] <Sixth Modification of the First Embodiment> 18(a) and 18(b), the fourth support column 35 and the fifth support column 33 in the first embodiment are arranged so as to overlap each other in the first direction D1. Similarly, the first support column 34 and the second support column 32 are arranged so as to overlap each other in the first direction D1. In other words, the fourth support column 35 and the fifth support column 33 are arranged so as to at least partially overlap each other when viewed in the vertical direction D3. The first support column 34 and the second support column 32 are arranged so as to at least partially overlap each other when viewed in the vertical direction D3.

[0066] However, the fourth support column 35 and the fifth support column 33, and the first support column 34 and the second support column 32 are not limited to such an arrangement. For example, as shown in FIG. 18(c), the fourth support column 35 and the fifth support column 33 of the housing 60 according to the sixth modification are arranged so as not to overlap each other in the first direction D1. Similarly, the first support column 34 and the second support column 32 are arranged so as not to overlap each other in the first direction D1. In other words, the fourth support column 35 and the fifth support column 33 are arranged so as not to overlap each other when viewed in the vertical direction D3. The first support column 34 and the second support column 32 are arranged so as not to overlap each other when viewed in the vertical direction D3.

[0067] At this time, the sixth support column 31 is arranged so as to overlap the fourth support column 35 and the fifth support column 33 in the first direction D1. Also, the third support column 30 is arranged so as to overlap the first support column 34 and the second support column 32 in the first direction D1.

[0068] <Second embodiment> [Support structure of the housing according to the second embodiment] Next, the support structure of the housing 260 of the printer main body 250 according to the second embodiment will be described with reference to FIGS. 19(a) to 21(c). FIG. 19(a) is a side view showing the left side of the printer 200 according to the second embodiment, and FIG. 19(b) is a perspective view showing the housing 260 taken along the line 19B-19B in FIG. 19(a). FIG. 20(a) is a perspective view showing the printer 200 taken along the line 20A-20A in FIG. 19(b), and FIG. 20(b) is a perspective view showing the printer 200 taken along the line 20B-20B in FIG. 19(b). FIG. 21(a) is a perspective view showing the left cover 211 and the right cover 212. FIG. 21(b) is a perspective view showing the housing 260, and FIG. 21(c) is another perspective view showing the housing 260.

[0069] 2(a) to 2(c), in the first embodiment, the pillar 17 and the bottom frame 4 extend downstream in the first direction D1 beyond the side plate 1a at the left front portion of the housing 60. A space is provided in the area surrounded by the pillar 17, the side plate 1a, and the bottom frame 4, and the third support portion 30 provided on the left cover 11 is configured to enter this space.

[0070] In the second embodiment, as shown in FIG. 19(b), a space S11 is provided between the frame body 201 and the left cover 211 on one side of the housing 260 in the second direction D2. More specifically, the space S11 is provided between the left side plate 201a of the frame body 201 and the left cover 211. The left cover 211 extends along the first direction D1 and the vertical direction D3, constitutes one side of the housing 260, and covers the side plate 201a. Furthermore, a space S12 is provided between the frame body 201 and the right cover 212 on the other side of the housing 260 in the second direction D2. More specifically, the space S12 is provided between the right side plate 201b of the frame body 201 and the right cover 212. Next, a configuration will be described in which a support structure, described later, is provided in the spaces S11 and S12, allowing the printer main body 250 to withstand loads in the second direction D2 and the vertical direction D3.

[0071] 19(a) to 21(c), the frame of the housing 260 is made up of a frame body 201 as a first frame and a feed frame 203 as a second frame. Side plates 201a and 201b of the frame body 201 are made up of a metal material such as sheet metal, and first support columns 234F, 234R and fourth support columns 235F, 235R of the frame body 201, which will be described later, and the feed frame 203 are made up of a resin material. The exterior of the housing 260 is made up of a top cover, a left cover 211, a right cover 212, a front cover 213, an inner rear cover, an inner cover, a discharge tray, and a rear cover 214, all of which are made up of a resin material.

[0072] The front cover 213 extends along the second direction D2 and the vertical direction D3 and is disposed downstream of the photosensitive drum 44 (see FIG. 13) in the first direction D1. The rear cover 214 extends along the second direction D2 and the vertical direction D3 and is disposed upstream of the photosensitive drum 44 (see FIG. 13) in the first direction D1.

[0073] 21(a), the left cover 211 has third support pillars 230F, 230R that protrude in the second direction D2 toward the inside of the printer body 250, i.e., toward the right cover 212. The right cover 212 has sixth support pillars 231F, 231R that protrude in the second direction D2 toward the inside of the printer body 250, i.e., toward the left cover 211. The left cover 211 and the right cover 212 are made of a resin material.

[0074] In the following description, components suffixed with the letter "F" or "R" indicate a pair of components, with one component suffixed with the letter "F" being arranged downstream in the first direction D1 from the other component suffixed with the letter "R." For example, the third support column 230F is arranged downstream in the first direction D1 from the third support column 230R, and the sixth support column 231F is arranged downstream in the first direction D1 from the sixth support column 231R.

[0075] 21(b) and 21(c), first support pillars 234F, 234R and fourth support pillars 235F, 235R are provided on the upper portion of the frame 201. The first support pillars 234F, 234R extend from the left side plate 201a in a direction away from the right side plate 201b, and the fourth support pillars 235F, 235R extend from the right side plate 201b in a direction away from the left side plate 201a. In other words, the first support pillars 234F, 234R and the fourth support pillars 235F, 235R extend toward the outside of the printer body 250 in the second direction D2.

[0076] The feed frame 203 attached to the lower part of the frame 201 is provided with second support columns 232F, 232R and fifth support columns 233F, 233R. The second support columns 232F, 232R and fifth support columns 233F, 233R extend outward from the printer body 250 in the second direction D2. The side plates 201a, 201b of the frame 201 are made of a metal material such as sheet metal. Furthermore, the first support columns 234F, 234R and fourth support columns 235F, 235R provided on the frame 201 and the feed frame 203 are made of a resin material.

[0077] The first support columns 234F, 234R and the second support columns 232F, 232R are arranged on one end side in the second direction D2 of the printer body 250, i.e., on the left side. The fourth support columns 235F, 235R and the fifth support columns 233F, 233R are arranged on the other end side in the second direction D2 of the printer body 250, i.e., on the right side.

[0078] As shown in Figures 20(a) and 20(b), the worker assembles the left cover 211 and the right cover 212 to the frame body 201. Then, as shown in Figure 20(a), the third support column 230F is disposed between the first support column 234F and the second support column 232F in the vertical direction D3 and is able to come into contact with the first support column 234F and the second support column 232F. The third support column 230F is also disposed at a position where at least a portion thereof overlaps with the first support column 234F and the second support column 232F when viewed in the vertical direction D3. The first support column 234F, the second support column 232F, and the third support column 230F constitute a support column structure PL4F at the left front portion of the housing 260.

[0079] 20(b), the third support column 230R is disposed between the first support column 234R and the second support column 232R in the vertical direction D3 and is capable of contacting the first support column 234R and the second support column 232R. The third support column 230R is disposed at a position where at least a portion thereof overlaps the first support column 234R and the second support column 232R when viewed in the vertical direction D3. The first support column 234R, the second support column 232R, and the third support column 230R constitute a support column structure PL4R at the left rear of the housing 260.

[0080] 20(a), the sixth support column 231F is disposed between the fourth support column 235F and the fifth support column 233F in the vertical direction D3 and is capable of contacting the fourth support column 235F and the fifth support column 233F. The sixth support column 231F is provided at a position where at least a portion thereof overlaps with the fourth support column 235F and the fifth support column 233F when viewed in the vertical direction D3. The fourth support column 235F, the fifth support column 233F, and the sixth support column 231F constitute a support column structure PL5F at the right front portion of the housing 260.

[0081] 20(b), the sixth support column 231R is disposed between the fourth support column 235R and the fifth support column 233R in the vertical direction D3 and is capable of contacting the fourth support column 235R and the fifth support column 233R. The sixth support column 231R is disposed at a position where at least a portion thereof overlaps with the fourth support column 235R and the fifth support column 233R when viewed in the vertical direction D3. The fourth support column 235R, the fifth support column 233R, and the sixth support column 231R constitute a support column structure PL5R at the right rear of the housing 260.

[0082] The support structures PL4F, PL4R, PL5F, and PL5R constitute part of the structure of the printer main body 250, and can receive an external force, particularly in the vertical direction D3, when the external force acts on the printer main body 250. For example, a load acting from above on the fourth support portion 235F can be received by the fifth support portion 233F via the sixth support portion 231F, and the load can be distributed over the entire housing 260.

[0083] 19(a) to 21(c), the first support pillars 234F, 234R, the second support pillars 232F, 232R, and the third support pillars 230F, 230R are disposed on the opposite side of the side plate 201a from the photosensitive drum 44 (see FIG. 13) in the second direction D2. Similarly, the fourth support pillars 235F, 235R, the fifth support pillars 233F, 233R, and the sixth support pillars 231F, 231R are disposed on the opposite side of the side plate 201b from the photosensitive drum 44 (see FIG. 13) in the second direction D2.

[0084] 20(a), the third support column 230F and the sixth support column 231F engage with the frame body 201 in the second direction D2, and the third support column 230F, the sixth support column 231F, and a portion of the frame body 201 form a support column structure PL6F. Similarly, as shown in FIG. 20(b), the third support column 230R and the sixth support column 231R engage with the frame body 201 in the second direction D2, and the third support column 230R, the sixth support column 231R, and a portion of the frame body 201 form a support column structure PL6R. The support columns PL6F and PL6R form part of the structure of the printer body 250, and can withstand an external force acting on the printer body 250, particularly in the second direction D2.

[0085] In the present embodiment, the third support columns 230F, 230R and the sixth support columns 231F, 231R are engaged with the frame body 201 in the second direction D2, but this is not limiting. For example, the third support columns 230F, 230R and the sixth support columns 231F, 231R may be engaged with the feed frame 203 in the second direction D2 to form support structures PL6F, PL6R.

[0086] [Advantages of the second embodiment] In this embodiment, the left cover 211 and the right cover 212, which are part of the exterior of the housing 260 of the printer 200, are utilized as part of the support structure PL4F, PL4R, PL5F, PL5R, PL6F, and PL6R, which are the structural components of the printer body 250. The first support members 234F and 234R, the fourth support members 235F and 235R, the second support members 232F and 232R, and the fifth support members 233F and 233R extend outward from the printer body 250 in the second direction D2.

[0087] For example, consider a case where a frame for a single-function printer is used in common with a frame for a multi-function printer, which has a larger product size in the second direction D2 than the single-function printer. In this case, first support columns 234F, 234R and fourth support columns 235F, 235R are added to the side panels 201a, 201b of the frame for the single-function printer, and a feed frame 203 is also added. As described above, portions of the support columns PL4F, PL4R, PL5F, PL5R, PL6F, and PL6R are made from portions of the left cover 211 and right cover 212, which are made of a resin material. This allows the printer 200 to be made lighter and less expensive while maintaining its rigidity.

[0088] <First Modification of the Second Embodiment> In the second embodiment, the first support pillars 234F, 234R and the fourth support pillars 235F, 235R are provided on the frame body 201, but this is not limiting. Fig. 22 is a perspective view showing a top cover 210 according to a first modified example. For example, in the first modified example of the second embodiment, the top cover 210 shown in Fig. 22 may be attached to the upper part of the frame body 201. That is, the first support pillars 234F, 234R and the fourth support pillars 235F, 235R may be provided on the top cover 210 instead of the frame body 201.

[0089] <Second Modification of the Second Embodiment> In the second embodiment, the third support pillars 230F, 230R and the sixth support pillars 231F, 231R are provided on the left cover 211 and the right cover 212, but this is not limiting. Figures 23(a) and 23(b) are perspective views showing a front cover 213 according to a second modified example, and Figures 23(c) and 23(d) are perspective views showing a rear cover 214 according to the second modified example. For example, in the second modified example of the second embodiment, the front cover 213 shown in Figures 23(a) and 23(b) and the rear cover 214 shown in Figures 23(c) and 23(d) may be attached to the front and rear of the frame 201.

[0090] 23(a) and 23(b), the front cover 213 has a third support pillar 230F and a sixth support pillar 231F. As shown in Figures 23(c) and 23(d), the rear cover 214 has a third support pillar 230R and a sixth support pillar 231R. That is, the third support pillars 230F, 230R and the sixth support pillars 231F, 231R may be provided on the front cover 213 and the rear cover 214 instead of the left cover 211 and the right cover 212.

[0091] <Third embodiment> [Support structure of the housing according to the third embodiment] Next, the support structure of the housing 360 of the printer main body 350 according to the third embodiment will be described with reference to FIGS. 24(a) to 27(b). FIG. 24(a) is a side view showing the left side of the printer 300 according to the third embodiment, and FIG. 24(b) is a perspective view showing the housing 360 taken along the cross section 24B-24B in FIG. 24(a). FIG. 25(a) is a perspective view showing the printer 300 taken along the cross section 25A-25A in FIG. 24(b), and FIG. 25(b) is a perspective view showing the printer 300 taken along the cross section 25B-25B in FIG. 24(b). FIG. 25(c) is a perspective view showing the printer 300 taken along the cross section 25C-25C in FIG. 24(b). Fig. 26(a) is an exploded perspective view showing the left cover 311, the right cover 312, and the front cover 313, and Fig. 26(b) is a perspective view showing the assembled left cover 311, the right cover 312, and the front cover 313. Fig. 27(a) is a perspective view showing the housing 360, and Fig. 27(b) is another perspective view showing the housing 360.

[0092] In the third embodiment, as shown in FIG. 24(b), a space S21 is provided between the frame body 301 and the left cover 311 on one side of the housing 360 in the second direction D2. More specifically, the space S21 is provided between the left side plate 301a of the frame body 301 and the left cover 311. The left cover 311 extends along the first direction D1 and the vertical direction D3, constitutes one side of the housing 360, and covers the side plate 301a. Furthermore, a space S22 is provided between the frame body 301 and the right cover 312 on the other side of the housing 360 in the second direction D2. More specifically, the space S22 is provided between the right side plate 301b of the frame body 301 and the right cover 312. Furthermore, a space S30 is provided on the downstream side of the frame body 301 in the first direction D1. More specifically, the space S30 is provided between the frame body 301 and the front cover 313. Then, a configuration will be described in which support structures, which will be described later, are provided in the spaces S21, S22, and S30, so that the printer main body 350 can withstand loads in the second direction D2 and the vertical direction D3.

[0093] 24(a) to 27(b), the frame of the housing 360 is composed of a frame body 301 as a first frame, and a feed frame 303 and a bottom frame 304 as a second frame. Side plates 301a and 301b of the frame body 301 are made of a metal material such as sheet metal, while first support columns 334F, 334R and fourth support columns 335F, 335R of the frame body 301, which will be described later, as well as the feed frame 303 and the bottom frame 304, are made of a resin material. The exterior of the housing 360 is composed of a top cover, a left cover 311, a right cover 312, a front cover 313, an inner rear cover, an inner cover, a discharge tray, and a rear cover 314, all of which are made of a resin material.

[0094] The front cover 313 extends along the second direction D2 and the vertical direction D3 and is disposed downstream of the photosensitive drum 44 (see FIG. 13) in the first direction D1. The rear cover 314 extends along the second direction D2 and the vertical direction D3 and is disposed upstream of the photosensitive drum 44 (see FIG. 13) in the first direction D1.

[0095] As shown in FIGS. 27(a) and 27(b), a feed frame 303 and a bottom frame 304 are attached to the lower part of the frame body 301 of the housing 360. The bottom frame 304 extends downstream in the first direction D1 from the side plates 301a and 301b of the frame body 301. First support columns 334F and 334R and fourth support columns 335F and 335R are provided on the upper part of the frame body 301. The first support columns 334F and 334R extend from the left side plate 301a in a direction away from the right side plate 301b. The first support column 334F extends downstream in the first direction D1 from the side plate 301a. The fourth support columns 335F and 335R extend from the right side plate 301b in a direction away from the left side plate 301a. The fourth support column 335F extends downstream in the first direction D1 from the side plate 301b. That is, the first support columns 334F, 334R and the fourth support columns 335F, 335R extend toward the outside of the printer body 250 in the second direction D2, and the first support column 334F and the fourth support column 335F extend downstream in the first direction D1.

[0096] A second support column 332R and a fifth support column 333R are provided on the feed frame 303 attached to the lower part of the frame 301. The second support column 332R and the fifth support column 333R extend toward the outside of the printer body 250 in the second direction D2. In addition, a second support column 332F and a fifth support column 333F are provided on the bottom frame 304 attached to the lower part of the frame 301. The second support column 332F and the fifth support column 333F extend toward the outside of the printer body 250 in the second direction D2 and downstream in the first direction D1.

[0097] The second support columns 332F, 332R and the fifth support columns 333F, 333R are disposed directly below the first support columns 334F, 334R and the fourth support columns 335F, 335R, respectively. The side plates 301a, 301b of the frame 301 are made of a metal material such as sheet metal. The first support columns 334F, 334R and the fourth support columns 335F, 335R provided on the frame 301, as well as the feed frame 303 and the bottom frame 304, are made of a resin material.

[0098] 24(b) and 26(a) and 26(b), the left cover 311 has third support pillars 330F, 330M, and 330R that protrude in the second direction D2 toward the inside of the printer body 350, i.e., toward the right cover 312. The right cover 312 has sixth support pillars 331F, 331M, and 331R that protrude in the second direction D2 toward the inside of the printer body 350, i.e., toward the left cover 311. The left cover 311 and the right cover 312 are made of a resin material.

[0099] As shown in Fig. 24(b), the worker assembles the left cover 311 and the right cover 312 to the frame 301. Then, as shown in Fig. 24(b), the third support column 330F and the sixth support column 331F are disposed in the space S30, the third support columns 330M and 330R are disposed in the space S21, and the sixth support columns 331M and 331R are disposed in the space S22. As a result, the third support columns 330F, 330M, and 330R of the left cover 311 and the sixth support columns 331F, 331M, and 331R of the right cover 312 form part of a support structure, which will be described later.

[0100] 25(a), on the left side of the rear portion of the printer 300, the third support column 330R is disposed between the first support column 334R and the second support column 332R in the vertical direction D3 and is capable of contacting the first support column 334R and the second support column 332R. Furthermore, the third support column 330R is disposed in a position where at least a portion thereof overlaps the first support column 334R and the second support column 332R when viewed in the vertical direction D3. The first support column 334R, the second support column 332R, and the third support column 330R constitute a support column structure PL7 at the left rear of the housing 360.

[0101] Similarly, on the right side of the rear of the printer 300, the sixth support column 331R is disposed between the fourth support column 335R and the fifth support column 333R in the vertical direction D3 and is capable of contacting the fourth support column 335R and the fifth support column 333R. The sixth support column 331R is also disposed in a position where at least a portion thereof overlaps the fourth support column 335R and the fifth support column 333R when viewed in the vertical direction D3. The fourth support column 335R, the fifth support column 333R, and the sixth support column 331R constitute a support column structure PL8 at the right rear of the housing 360.

[0102] The support structures PL7 and PL8 constitute part of the structure of the printer body 350, and can withstand an external force, particularly in the vertical direction D3, when the external force acts on the rear surface of the printer body 350. For example, a load acting from above on the fourth support portion 335R can be received by the fifth support portion 333R via the sixth support portion 331R, and the load can be distributed over the entire housing 360.

[0103] Furthermore, the third support column 330R and the sixth support column 331R engage with the frame body 301 in the second direction D2, and the third support column 330R, the sixth support column 331R, and a portion of the frame body 301 constitute a support column structure PL9R. Similarly, as shown in Figure 25(b), the third support column 330M and the sixth support column 331R engage with the frame body 301 in the second direction D2, and the third support column 330M, the sixth support column 331M, and a portion of the frame body 301 constitute a support column structure PL9M. The support columns PL9R and PL9M constitute part of the structure of the printer body 350, and can withstand an external force acting on the printer body 350, particularly in the second direction D2.

[0104] In the present embodiment, the third support columns 330M, 330R and the sixth support columns 331M, 331R are engaged with the frame body 301 in the second direction D2, but this is not limiting. For example, the third support columns 330M, 330R and the sixth support columns 331M, 331R may be engaged with the feed frame 303 or the bottom frame 304 in the second direction D2 to form support structures PL9M, PL9R.

[0105] 25(c), on the left side of the front surface of the printer 300, the third support column 330F is disposed between the first support column 334F and the second support column 332F in the vertical direction D3 and is capable of contacting the first support column 334F and the second support column 332F. The third support column 330F is disposed at a position where at least a portion thereof overlaps the first support column 334F and the second support column 332F when viewed in the vertical direction D3. The first support column 334F, the second support column 332F, and the third support column 330F constitute a support column structure PL10 at the left front portion of the housing 360.

[0106] Similarly, on the right side of the front of the printer 300, the sixth support column 331F is disposed between the fourth support column 335F and the fifth support column 333F in the vertical direction D3 and is capable of contacting the fourth support column 335F and the fifth support column 333F. The sixth support column 331F is disposed at a position where at least a portion thereof overlaps with the fourth support column 335F and the fifth support column 333F when viewed in the vertical direction D3. The fourth support column 335F, the fifth support column 333F, and the sixth support column 331F constitute a support column structure PL11 at the right front of the housing 360.

[0107] The support structures PL10, PL11 constitute part of the structure of the printer body 350, and can withstand an external force, particularly in the vertical direction D3, when the external force acts on the front surface of the printer body 350. For example, a load acting from above on the fourth support portion 335F can be received by the fifth support portion 333F via the sixth support portion 331F, and the load can be distributed over the entire housing 360.

[0108] 24(a) to 27(b), the first support pillars 334F, 334R, the second support pillars 332F, 332R, and the third support pillars 330F, 330M, 330R are disposed on the opposite side of the side plate 301a from the photosensitive drum 44 (see FIG. 13) in the second direction D2. Similarly, the fourth support pillars 335F, 335R, the fifth support pillars 333F, 333R, and the sixth support pillars 331F, 331M, 331R are disposed on the opposite side of the side plate 301b from the photosensitive drum 44 (see FIG. 13) in the second direction D2. Furthermore, the first support column 334F, the second support column 332F, the third support column 330F, the fourth support column 335F, the fifth support column 333F and the sixth support column 331F are arranged downstream of the side plates 301a and 301b in the first direction D1.

[0109] 26(a) and 26(b), a seventh support column 336 is provided on the front cover 313, which is part of the housing 360. The third support column 330F and the sixth support column 331F engage with the seventh support column 336 of the front cover 313 in the second direction D2, and the third support column 330F, the sixth support column 331F, and the seventh support column 336 form a support structure PL12. The support structure PL12 forms part of the structure of the printer body 350, and can withstand an external force acting on the printer body 350, particularly in the second direction D2.

[0110] [Advantages of the third embodiment] In this embodiment, the left cover 311 and the right cover 312, which are part of the exterior of the housing 360 of the printer 300, are utilized as part of the support structures PL7, PL8, PL9M, PL9R, PL10, PL11, and PL12, which are structural components of the printer main body 350. The first support structures 334F and 334R, the fourth support structures 335F and 335R, the second support structures 332F and 332R, and the fifth support structures 333F and 333R extend toward the outside of the printer main body 250 in the second direction D2. The first support structure 334F, the second support structure 332F, the fourth support structure 335F, and the fifth support structure 333F extend downstream in the first direction D1 from the side plates 301a and 301b of the frame 301.

[0111] For example, consider a case where a frame for a single-function printer is used in common with a frame for a multi-function printer, which has a larger product size in the first direction D1 and the second direction D2 than the single-function printer. In this case, first support columns 334F, 334R and fourth support columns 335F, 335R are added to the side panels 301a, 301b of the frame for the single-function printer, and a feed frame 303 and a bottom frame 304 are also added. As described above, portions of the support structures PL7, PL8, PL9M, PL9R, PL10, PL11, and PL12 are made from portions of the left cover 311 and right cover 312, which are made of a resin material. This allows the printer 300 to be made lighter and less expensive while maintaining its rigidity.

[0112] <First Modification of the Third Embodiment> In the third embodiment, the first support columns 334F, 334R and the fourth support columns 335F, 335R are provided on the frame body 301, but this is not limiting. For example, in a first modified example of the third embodiment, the top cover 310 shown in Fig. 22 may be attached to the top of the frame body 301. That is, the first support columns 334F, 334R and the fourth support columns 335F, 335R may be provided on the top cover 310 instead of the frame body 301.

[0113] <Second Modification of the Third Embodiment> In the third embodiment, the third support columns 330F, 330R and the sixth support columns 331F, 331R are provided on the left cover 311 and the right cover 312, but this is not limiting. Fig. 28(a) is a side view showing the left side of the printer 300 according to the second modified example, Fig. 28(b) is a perspective view showing the housing 360 according to the second modified example, and Fig. 28(c) is another perspective view showing the housing 360 according to the second modified example. Fig. 29(a) is an exploded perspective view showing the housing 360 according to the second modified example, and Fig. 29(b) is another perspective view showing the housing 360 according to the second modified example.

[0114] For example, in a second modified example of the third embodiment, the front cover 313 and the rear cover 214 shown in FIGS. 28(b)(c) and 29(a)(b) may be attached to the front and rear of the frame 301. FIG. 28(a) is a side view showing the left side of the printer 300 according to the second modified example. FIGS. 28(b)(c) are perspective views showing the housing 360 taken along the cross section 28BC-28BC in FIG. 28(a). FIGS. 29(a)(b) are exploded perspective views showing the housing 360 taken along the cross section 28BC-28BC in FIG. 28(a).

[0115] As shown in FIGS. 28(b) and 28(c) and 29(a) and 29(b), the front cover 313 has a third support column 330F and a sixth support column 331F. The rear cover 314 has a third support column 330R and a sixth support column 331R. That is, the third support columns 330F, 330R and the sixth support columns 331F, 331R may be provided on the front cover 313 and the rear cover 314 instead of the left cover 311 and the right cover 312. In this case, the left cover 311, which serves as the fourth side cover, is provided with a third support column 330M as a third engagement portion that engages with the side plate 301a, the feed frame 303, or the bottom frame 304 in the second direction D2. The right cover 312 is provided with a sixth support column 331M that engages with the side plate 301b, the feed frame 303, or the bottom frame 304 in the second direction D2.

[0116] <Other embodiments> In the first embodiment, the support structures PL1 and PL2 are provided at the front left and front right parts of the printer body 50, respectively, but this is not limiting. For example, the support structures PL1 and PL2 may be provided at the rear left and rear right parts of the printer body 50, respectively, and the locations are not limited.

[0117] Furthermore, in the first embodiment, the pillars 17 are provided separately from the side plates 1a, but they may be formed integrally with the side plates 1a.

[0118] Furthermore, while the above-described embodiments have been described using an electrophotographic printer, the present invention is not limited to this. For example, the present invention can also be applied to an inkjet image forming apparatus that forms an image on a sheet by ejecting ink liquid from nozzles. For example, an inkjet printer houses a print head inside a frame 1. The print head ejects ink onto a recording material while moving in a second direction D2 along a head guide suspended on side plates 1a and 1b of the frame 1.

[0119] In addition, in all of the above-described embodiments, the left cover and the right cover are formed to extend along the discharge direction DD and the vertical direction D3, but this is not limiting. For example, the left cover and the right cover may be formed to extend along the pull-out direction of the cassette that stores sheets and the vertical direction D3.

[0120] In addition, in all of the above-described embodiments, the bottom frame and the feed frame are made of a resin material, but this is not limiting. For example, the bottom frame and the feed frame may be made of a metal material such as sheet metal. Furthermore, the first support column and the second support column provided on the frame body may also be made of a metal material such as sheet metal. In this case, the first support column and the second support column may be provided integrally with the side plate of the frame body or separately.

[0121] The above-described embodiments and modifications may be combined in any desired manner. Preferably, each support column in the above-described embodiments has a size of at least several centimeters in the vertical direction.

[0122] The disclosure of the present embodiment also includes the following configuration examples and method examples. (Configuration 1) an image forming section including an image carrier that carries an image and forms an image on a sheet; a housing that houses the image forming unit therein and has a discharge port formed therein for discharging a sheet on which an image is formed by the image forming unit, the housing having a first frame with side plates that support longitudinal ends of the image carrier, a second frame that is disposed below the first frame in the vertical direction, a side cover that constitutes one side of the housing, and a top cover that constitutes a top surface of the housing; At least one of the top cover and the first frame has a first support portion, the second frame has a second support column disposed below the first support column, The side cover has a third support column disposed between the first support column and the second support column in the vertical direction, the third support column being provided so as to be able to come into contact with the first support column and the second support column in the vertical direction, and at least a portion of the third support column being provided at a position overlapping the first support column and the second support column when viewed in the vertical direction. An image forming apparatus characterized by: (Configuration 2) A load acting from above on the first support column can be received by the second support column via the third support column. 2. The image forming apparatus according to claim 1, (Configuration 3) The length of the second frame in the vertical direction is shorter than the length of the first frame in the vertical direction. 3. The image forming apparatus according to claim 1, wherein: (Configuration 4) the side plate is made of a metal material, The side cover is made of a resin material. 4. The image forming apparatus according to any one of configurations 1 to 3. (Configuration 5) The first support column and the second frame are made of a resin material. 5. The image forming apparatus according to configuration 4. (Configuration 6) the first support portion is made of a resin material, The second frame is made of a metal material. 5. The image forming apparatus according to configuration 4. (Configuration 7) The second support column is disposed at a position where it at least partially overlaps with the first support column when viewed in the vertical direction. 7. The image forming apparatus according to any one of configurations 1 to 6. (Configuration 8) The second support column is disposed at a position where it does not overlap with the first support column when viewed in the vertical direction. 7. The image forming apparatus according to any one of configurations 1 to 6. (Configuration 9) the first frame includes the side plate and an extension member fixed to the side plate and extending downstream of the side plate in a discharge direction in which sheets are discharged from the discharge port, The extension member constitutes at least a part of the first support column and is provided so as to be able to come into contact with the third support column. 9. The image forming apparatus according to any one of configurations 1 to 8. (Configuration 10) the second frame extends downstream of the side plate in a discharge direction in which the sheets are discharged from the discharge port, The second support portion is disposed directly below the extension member. 10. The image forming apparatus according to configuration 9, (Configuration 11) the first support column, the second support column, and the third support column are arranged so as to overlap the side plates in the longitudinal direction of the image carrier. 11. The image forming apparatus according to any one of configurations 1 to 10. (Configuration 12) the first support column, the second support column, and the third support column are disposed on the opposite side of the side plate from the image carrier in the longitudinal direction of the image carrier. 9. The image forming apparatus according to any one of configurations 1 to 8. (Configuration 13) the first support column, the second support column, and the third support column are disposed on the opposite side of the side plate from the image carrier in the longitudinal direction of the image carrier, and downstream of the side plate in the discharge direction in which the sheet is discharged from the discharge port. 11. The image forming apparatus according to any one of configurations 1 to 10. (Configuration 14) The top cover constitutes the first support column and is provided so as to be in contact with the third support column. 14. The image forming apparatus according to any one of configurations 1 to 13. (Configuration 15) The side cover extends along the discharge direction in which sheets are discharged from the discharge port and along the vertical direction, and covers the side plate. 15. The image forming apparatus according to any one of configurations 1 to 14. (Configuration 16) the third support column engages with the side plate or the second frame in the longitudinal direction of the image carrier; 16. The image forming apparatus according to configuration 15. (Configuration 17) the side cover is a first side cover, the housing has a second side cover that extends along the discharge direction and the vertical direction and forms a side of the housing opposite to the one side in the longitudinal direction of the image carrier; At least one of the top cover and the first frame has a fourth support column, the second frame has a fifth support column disposed below the fourth support column, the second side cover has a sixth support column disposed between the fourth support column and the fifth support column in the vertical direction, the sixth support column being provided so as to be able to come into contact with the fourth support column and the fifth support column in the vertical direction, and being provided at a position where at least a portion of the sixth support column overlaps with the fourth support column and the fifth support column when viewed in the vertical direction; 17. The image forming apparatus according to configuration 15 or 16. (Configuration 18) the first support column, the second support column, and the third support column are disposed on one end side of the housing in the longitudinal direction, the fourth support column, the fifth support column, and the sixth support column are disposed on the other end side of the housing in the longitudinal direction. 18. The image forming apparatus according to configuration 17. (Configuration 19) the third support column and the sixth support column engage with the side plate or the second frame in the longitudinal direction of the image carrier; 19. The image forming apparatus according to configuration 18. (Configuration 20) the housing has a third side cover extending along the longitudinal direction and the vertical direction, The third side cover has a first engagement portion that engages with the third support column and a second engagement portion that engages with the sixth support column, and connects the first side cover and the second side cover. 20. The image forming apparatus according to claim 18 or 19, (Configuration 21) The first engagement portion and the second engagement portion are disposed at approximately the same height in the vertical direction. 21. The image forming apparatus according to configuration 20. (Configuration 22) The third side cover has a rib extending in the longitudinal direction. 22. The image forming apparatus according to configuration 20 or 21. (Configuration 23) the side cover extends along the longitudinal direction and the vertical direction of the image carrier and is disposed downstream of the image carrier in a discharge direction in which a sheet is discharged from the discharge port. 15. The image forming apparatus according to any one of configurations 1 to 14. (Configuration 24) the housing has a fourth side cover that extends along the discharge direction in which sheets are discharged from the discharge port and the vertical direction and covers the side plate; the fourth side surface cover has a third engagement portion that engages with the side plate or the second frame in the longitudinal direction; 24. The image forming apparatus according to configuration 23. (Configuration 25) At least one of the top cover and the first frame has a fourth support column, the second frame has a fifth support column disposed below the fourth support column, The side cover has a sixth support column disposed between the fourth support column and the fifth support column in the vertical direction, the sixth support column being provided so as to be able to come into contact with the fourth support column and the fifth support column in the vertical direction, and being provided at a position where at least a portion of the sixth support column overlaps with the fourth support column and the fifth support column when viewed in the vertical direction. 25. The image forming apparatus according to configuration 23 or 24. (Configuration 26) the first support column, the second support column, and the third support column are disposed on one end side of the housing in the longitudinal direction, the fourth support column, the fifth support column, and the sixth support column are disposed on the other end side of the housing in the longitudinal direction. 26. The image forming apparatus according to configuration 25. (Configuration 27) the side cover extends along the longitudinal direction and the vertical direction of the image carrier, and is disposed upstream of the image carrier in a discharge direction in which a sheet is discharged from the discharge port. 15. The image forming apparatus according to any one of configurations 1 to 14. (Configuration 28) the housing has a fourth side cover that extends along the discharge direction in which sheets are discharged from the discharge port and the vertical direction and covers the side plate; the fourth side surface cover has a third engagement portion that engages with the side plate or the second frame in the longitudinal direction; 28. The image forming apparatus according to configuration 27. (Configuration 29) At least one of the top cover and the first frame has a fourth support column, the second frame has a fifth support column disposed below the fourth support column, The side cover has a sixth support column disposed between the fourth support column and the fifth support column in the vertical direction, the sixth support column being provided so as to be able to come into contact with the fourth support column and the fifth support column in the vertical direction, and being provided at a position where at least a portion of the sixth support column overlaps with the fourth support column and the fifth support column when viewed in the vertical direction. 29. The image forming apparatus according to configuration 27 or 28. (Configuration 30) the first support column, the second support column, and the third support column are disposed on one end side of the housing in the longitudinal direction, the fourth support column, the fifth support column, and the sixth support column are disposed on the other end side of the housing in the longitudinal direction. 30. The image forming apparatus according to claim 29, (Configuration 31) The image reading device is disposed above the housing and is capable of reading an image on the sheet. 31. The image forming apparatus according to any one of configurations 1 to 30. [Explanation of symbols]

[0123] 1a, 201a, 301a: Side plate / 4, 203, 303, 304: Second frame (bottom frame, feed frame) / 10: Top cover / 11, 211, 311: Side cover, first side cover, fourth side cover (left cover) / 12: Second side cover (right cover) / 13: Third side cover (front cover) / 13a: First engagement part / 13b: Second engagement part / 13c: Rib / 17: Extension member (pillar) / 30, 230F, 330F, 330R: Third support part / 31, 231F, 331F, 331R: Sixth support part / 32, 23 2F, 332R: second support column / 33, 233F, 333R: fifth support column / 34, 234F, 334R: first support column / 35, 235F, 335R: fourth support column / 40: first frame / 44: image carrier (photosensitive drum) / 60, 260, 360: housing / 70: image reading device / 80: image forming unit / 81: discharge port / 100: image forming device (printer) / 201, 301: frame body (first frame) / 331M: third engagement section (third support column) / DD: discharge direction / D2: longitudinal direction (second direction) / D3: vertical direction / h1, h2: length

Claims

1. an image forming section including an image carrier that carries an image and forms an image on a sheet; a housing that houses the image forming unit therein and has a discharge port formed therein for discharging sheets on which images are formed by the image forming unit, the housing having a first frame, a second frame, a side cover that constitutes one side of the housing, and a top cover that constitutes a top surface of the housing; At least one of the top cover and the first frame has a supported portion, the second frame has a first supporting portion disposed below the supported portion, the side cover has a second support portion that is disposed between the supported portion and the first support portion in the vertical direction and is capable of supporting the supported portion, the first support portion supports the second support portion in the vertical direction, the second support portion is provided at a position where at least a portion thereof overlaps with the supported portion and the first support portion when viewed in the vertical direction, the first frame includes a side plate that supports one end of the image carrier in a longitudinal direction, and an extension member that is an exterior member fixed to the side plate and extends downstream of the side plate in a direction intersecting the vertical direction, The extension member forms at least a part of the supported portion and supports the second support portion. An image forming apparatus characterized by:

2. The first support portion can receive a load acting from above on the supported portion via the second support portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. The length of the second frame in the vertical direction is shorter than the length of the first frame in the vertical direction.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

4. the side plate is made of a metal material, The side cover is made of a resin material.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

5. the supported portion and the second frame are made of a resin material.

5. The image forming apparatus according to claim 4.

6. the supported portion is made of a resin material, The second frame is made of a metal material.

5. The image forming apparatus according to claim 4.

7. The first support portion is disposed at a position where it at least partially overlaps with the supported portion when viewed in the vertical direction.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

8. The first support portion is disposed at a position that does not overlap with the supported portion when viewed in the vertical direction.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. the second frame extends downstream of the side plate in a discharge direction in which the sheets are discharged from the discharge port, The first support portion is disposed directly below the extension member.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

10. the supported portion, the first supporting portion, and the second supporting portion are arranged so as to overlap with the side plates in the longitudinal direction of the image carrier.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

11. the supported portion, the first supporting portion, and the second supporting portion are disposed on the side opposite to the image carrier with respect to the side plate in the longitudinal direction of the image carrier.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

12. the supported portion, the first supporting portion, and the second supporting portion are disposed on the opposite side of the side plate from the image carrier in the longitudinal direction of the image carrier, and downstream of the side plate in the discharge direction in which the sheet is discharged from the discharge port.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

13. The top cover constitutes the supported portion and is provided so as to be in contact with the second supporting portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

14. The side cover extends along the discharge direction in which sheets are discharged from the discharge port and along the vertical direction, and covers the side plate.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

15. the second support portion engages with the side plate or the second frame in the longitudinal direction of the image carrier; 15. The image forming apparatus according to claim 14.

16. the side cover is a first side cover, the supported portion is a first supported portion, the housing has a second side cover that extends along the ejection direction and the vertical direction and forms a side of the housing opposite to the one side in the longitudinal direction of the image carrier; At least one of the top cover and the first frame has a second supported portion, the second frame has a third supporting portion disposed below the second supported portion, the second side cover has a fourth support portion that is disposed between the second supported portion and the third supported portion in the vertical direction and is capable of supporting the second supported portion, the third support portion supports the fourth support portion in the vertical direction, the fourth support portion is provided at a position where at least a portion thereof overlaps with the second supported portion and the third support portion when viewed in the vertical direction; 15. The image forming apparatus according to claim 14.

17. the first supported portion, the first supporting portion, and the second supporting portion are disposed on one end side of the housing in the longitudinal direction, the second supported portion, the third supporting portion, and the fourth supporting portion are disposed on the other end side of the housing in the longitudinal direction.

17. The image forming apparatus according to claim 16.

18. the second support portion and the fourth support portion engage with the side plate or the second frame in the longitudinal direction of the image carrier; 18. The image forming apparatus according to claim 17.

19. the housing has a third side cover extending along the longitudinal direction and the vertical direction, the third side cover has a first engaging portion that engages with the second support portion and a second engaging portion that engages with the fourth support portion, and connects the first side cover and the second side cover; 18. The image forming apparatus according to claim 17.

20. The first engaging portion and the second engaging portion are disposed at approximately the same height in the vertical direction.

20. The image forming apparatus according to claim 19.

21. the third side cover has a rib extending in the longitudinal direction; 20. The image forming apparatus according to claim 19.

22. the side cover extends along the longitudinal direction and the vertical direction of the image carrier and is disposed downstream of the image carrier in a discharge direction in which a sheet is discharged from the discharge port.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

23. the housing has a fourth side cover that extends along the ejection direction and the vertical direction and covers the side plate, the fourth side cover has a third engagement portion that engages with the side plate or the second frame in the longitudinal direction; 23. The image forming apparatus according to claim 22.

24. The supported portion is a first supported portion, At least one of the top cover and the first frame has a second supported portion, the second frame has a third supporting portion disposed below the second supported portion, the side cover has a fourth support portion that is disposed between the second supported portion and the third supported portion in the vertical direction and is capable of supporting the second supported portion, the third support portion supports the fourth support portion in the vertical direction, the fourth support portion is provided at a position where at least a portion thereof overlaps with the second supported portion and the third support portion when viewed in the vertical direction; 23. The image forming apparatus according to claim 22.

25. the supported portion, the first supporting portion, and the second supporting portion are disposed on one end side of the housing in the longitudinal direction, the second supported portion, the third supporting portion, and the fourth supporting portion are disposed on the other end side of the housing in the longitudinal direction.

25. The image forming apparatus according to claim 24.

26. the side cover extends along the longitudinal direction and the vertical direction of the image carrier, and is a cover disposed upstream of the image carrier in a discharge direction in which a sheet is discharged from the discharge port.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

27. the housing has a fourth side cover that extends along the ejection direction and the vertical direction and covers the side plate, the fourth side cover has a third engagement portion that engages with the side plate or the second frame in the longitudinal direction; 27. The image forming apparatus according to claim 26.

28. The supported portion is a first supported portion, At least one of the top cover and the first frame has a second supported portion, the second frame has a third supporting portion disposed below the second supported portion, the side cover has a fourth support portion that is disposed between the second supported portion and the third supported portion in the vertical direction and is capable of supporting the second supported portion, the third support portion supports the fourth support portion in the vertical direction, the fourth support portion is provided at a position where at least a portion thereof overlaps with the second supported portion and the third support portion when viewed in the vertical direction; 27. The image forming apparatus according to claim 26.

29. the first supported portion, the first supporting portion, and the second supporting portion are disposed on one end side of the housing in the longitudinal direction, the second supported portion, the third supporting portion, and the fourth supporting portion are disposed on the other end side of the housing in the longitudinal direction.

29. The image forming apparatus according to claim 28.

30. The image reading device is disposed above the housing and is capable of reading an image on the sheet.

30. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

Images