imaging device

Abstract

The present invention relates to an image forming apparatus comprising: a frame having (i) a resin-molded bottom surface and (ii) a side surface that is (a) integrally resin-molded with the bottom surface and (b) extends upward from the bottom surface; an internal structure capable of supporting an image forming portion for forming an image on a recording material; and a screw for fixing the internal structure to the bottom surface of the frame, wherein the side surface is provided so as to surround the internal structure, at least one of the frame and the internal structure includes at least one restriction portion that restricts relative movement between the internal structure and the frame in a direction perpendicular to the bottom surface, and the at least one restriction portion is provided in a position that is less than a distance from the bottom surface in a vertical direction.

Description

[0001] This divisional application is based on a Chinese patent application No. 201910060623.0 filed on January 23, 2019, with the title of “Imaging device”, which claims priority of Japanese application No. 2018-009611 filed on January 24, 2018. TECHNICAL FIELD

[0002] The present invention relates to an imaging device. BACKGROUND

[0003] An imaging device such as a printer and a copier has a frame for storing an internal structure including an image forming unit. FIG. 9 An exemplary frame structure for a conventional imaging device is shown. In FIG. 9 In the conventional structure, a frame for an imaging device 100 includes a lower frame A having a bottom surface and side surfaces 104, 105, and an upper frame B having an upper surface 102 and side surfaces 101, 103, and the lower frame and the upper frame are assembled in a vertical direction. SUMMARY

[0004] As in the conventional structure, when two bottomed frames A and B are assembled in the vertical direction by screw fastening to integrally form a frame for the imaging device 100, the following configuration is used to ensure the total rigidity of the imaging device 100. More specifically, edge portions 107 and 108 extending inwardly from the side surfaces in parallel with the bottom surface (or the upper surface 102) are provided near the opening portions of the frames A and B, and the edge portions 107 and 108 are provided with screw holes 110 so that screws 106 are fastened for fixation. The edge portions 107 and 108 are indicated in FIG. 9 In the conventional structure, the edge portions 107 and 108 are indicated in

[0005] The present invention provides a solution to the described problem, and an object of the present invention is to provide a technology for allowing an imaging device to have sufficient rigidity while limiting an increase in the size of the imaging device.

[0006] An imaging device according to the present invention includes:

[0007] a frame having (i) a resin-molded bottom surface and (ii) a side surface that is (a) integrally resin-molded with the bottom surface and (b) extends upwardly from the bottom surface;

[0008] an internal structure capable of supporting an image forming portion for forming an image on a recording material; and

[0009] screws for fixing the inner structure to a bottom surface of the frame,

[0010] wherein the side surface is provided to surround the inner structure,

[0011] at least one of the frame and the inner structure includes at least one restriction portion which restricts relative movement between the inner structure and the frame in a direction perpendicular to the bottom surface, and

[0012] the at least one restriction portion is provided in a position which is closer to the end of the side surface in a vertical direction than to the bottom surface in the vertical direction.

[0013] According to the present application, it is possible to ensure sufficient rigidity of the image forming apparatus while restricting an increase in size of the image forming apparatus.

[0014] Other features of the present application will become apparent from the following description of exemplary embodiments with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0015] FIG. 1 is a schematic sectional view of an image forming apparatus according to a first embodiment of the present application;

[0016] FIG. 2A and FIG. 2B is a perspective view of the image forming apparatus according to the first embodiment;

[0017] FIG. 3 is a view for explaining how the inner structure and the frame are fixed at a bottom portion of the image forming apparatus according to the first embodiment;

[0018] FIG. 4A to FIG. 4E is a view for explaining an engagement arrangement of the inner structure and the frame according to the first embodiment;

[0019] FIG. 5A and FIG. 5B is a view for explaining deformation of the image forming apparatus in a left-right direction according to the first embodiment;

[0020] FIG. 6 is a view for explaining an engagement arrangement of the inner structure and the frame at an upper portion of the image forming apparatus according to the first embodiment;

[0021] FIG. 7A and FIG. 7B is a view for explaining deformation of the image forming apparatus in a front-rear direction according to the first embodiment;

[0022] FIG. 8A to FIG. 8Eis a view for explaining an internal structure and a frame engagement arrangement according to a second embodiment of the present application; and

[0023] FIG. 9 is a view for explaining a conventional arrangement. DETAILED DESCRIPTION

[0024] First Embodiment

[0025] A first embodiment of the present application will be described. Note that according to the first embodiment, the image forming apparatus according to the present application is applied to an electrophotographic image forming apparatus, and a monochrome electrophotographic printer which can be provided with a single detachable process cartridge will be described by way of example. However, the present application can be applied to an image forming apparatus having an internal structure and a four-sided frame for storing the internal structure, the four-sided frame including a bottom surface, a front surface, a rear surface, a left surface, and a right surface, and is not limited by the exemplary application according to the first embodiment. For example, for an image forming apparatus forming a full-color image, the number of detachable process cartridges can be more than one (e.g., four). The present application can be applied to a copying machine, a facsimile machine, and a multifunction apparatus containing functions of all of the above-described devices, for example.

[0026] Description of General Structure of Overall Image Forming Apparatus

[0027] FIG. 1 is a schematic cross-sectional view taken along a direction perpendicular to the left-right direction of the image forming apparatus according to the first embodiment. Note that the left-right direction herein refers to a left-right direction observed from the front of the image forming apparatus and a direction parallel to the mounting surface of the image forming apparatus and perpendicular to the sheet surface of FIG. 1 . The front-rear direction refers to a direction connecting the front and the rear of the image forming apparatus and a direction parallel to the mounting surface of the image forming apparatus and parallel to the left-right direction of the sheet surface of FIG. 1 . In FIG. 1 , the rightward in the sheet surface corresponds to the frontward direction, and the leftward corresponds to the rearward direction.

[0028] The image forming apparatus 10 forms an image on a recording medium using an electrophotographic image forming process. The image forming apparatus 10 includes a detachable process cartridge 11 as an image forming unit. The detachable process cartridge 11 includes an electrophotographic photosensitive member (hereinafter as "photosensitive drum") and a developing unit 15 that develops a latent image formed on the photosensitive drum 1. The image forming apparatus 10 has an optical unit 18 that forms an electrostatic latent image by laser exposure to the photosensitive drum 1 as a photosensitive member based on image data. The image forming apparatus 10 forms a monochrome image on a recording material S (for example, a paper sheet, a plastic sheet, and a fabric sheet) as a recording medium based on the image data. The process cartridge 11 stores black toner. The recording material S is inserted into the image forming apparatus 10 from an opening at a front face of the image forming apparatus 10 and is fed by a paper feed device 13 to a nip portion between a transfer roller 12 and the photosensitive drum 1 as a photosensitive member. An electrostatic latent image is formed on the photosensitive drum 1 by the optical unit 18 based on the image data, and the electrostatic latent image is developed into a toner image by the developing unit 15. The transfer roller 12 presses the recording material S toward the photosensitive drum 1 in a process in which the recording material S passes through the nip portion between the photosensitive drum 1 and the transfer roller 12. The transfer roller 12 is supplied with a bias voltage of a polarity opposite to a polarity with which the toner is charged by a bias power source, and the toner image formed on a surface of the photosensitive drum 1 is transferred onto a surface of the recording material S. A fixing unit 14 is provided downstream of the nip portion between the transfer roller 12 and the photosensitive drum 1, and the recording material S carrying the toner image passes through the fixing unit 14 at which the toner is heated and pressed to be fused and fixed on the recording material S. By these operation steps, a monochrome printed image is formed on a surface of the recording material S using the photosensitive member.

[0029] Outside of the image forming apparatus

[0030] The outside of the image forming apparatus 10 will now be described with reference to FIG. 2A and FIG. 2B The outside of the image forming apparatus 10 will now be described with reference to

[0031] FIG. 2Ais a perspective view of the imaging device 10 as viewed from the front and above. The imaging device 10 has an internal structure 20 capable of supporting an imaging unit for forming an image on a recording material S and a frame 30 for storing the internal structure. The frame 30 has a resin-molded bottom surface 31 and side surfaces 32 that are integrally resin-molded with the bottom surface 31 and extend upward from the bottom surface 31 and are open on the upper side. The frame 30 is formed by so-called resin integral molding. Thus, the resin-molded bottom surface 31 and the side surfaces 32 that are integrally resin-molded with the bottom surface 31 are formed continuously. The side surfaces 32 are provided so as to surround the internal structure 20. The imaging device 10 has an upper cover 35 provided so as to cover an opening on an upper surface of the frame 30 and an upper side portion of the internal structure 20 and a pivotally openable cover 36 having a rotation center at the upper cover 35.

[0032] The paper feed port 17 is provided at a front portion of the side surface 32 of the frame 30, and a paper feed tray 25 having a rotation center located near the paper feed port 17 is attached to the paper feed port 17. The paper feed tray 25 has a guide member 16 that guides the recording material S.

[0033] FIG. 2B is a perspective view of the imaging device 10 indicating a schematic partial cross-sectional view as viewed from the front and above. The upper cover 35 engages with a rear end portion of the side surface 32 of the frame 30 and is fastened and fixed to an upper portion of the internal structure 20 by screws 34.

[0034] The openable cover 36 is attached to have a rotation center at the upper cover 35 and is rotatable with respect to the imaging device 10 between a closed position and an open position. When the openable cover 36 is in the closed position, the imaging device 10 is allowed to form an image, and when the openable cover 36 is in the open position, the process cartridge 11 can be inserted into / from the imaging device 10. Note that, according to the embodiment, the openable cover 36 is attached to have a rotation center at the upper cover 35, but the openable cover 36 can be attached to have a rotation center at the internal structure 20 or the frame 30.

[0035] In this way, the upper cover 35 and the openable cover 36 are members mainly for covering the upper portion of the internal structure 20 and, in combination with the lower frame, are not expected to function as members for ensuring the rigidity of the device as a whole, which is the case with the conventional device shown, in which the upper cover and the openable cover function to ensure the rigidity of the device as a whole. Thus, the upper cover 35 and the openable cover 36 can be formed to have a simple and flat structure, which is advantageous in that an increase in the size and cost of the device can be limited as compared to the conventional device shown.

[0036] The connection between the frame and the internal structure

[0037] Now, refer to FIG. 3 to FIG. 6 Describe the method of fixing the frame 30 and the internal structure 20.

[0038] First, the connection between the frame 30 at the bottom of the imaging device 10 and the internal structure 20 will be described.

[0039] FIG. 3 This is a perspective view of the frame 30 and internal structure 20 as seen from the front and bottom. For ease of description, only a portion of the frame 30 near the bottom surface 31 is shown.

[0040] The imaging device 10 has screws 40 for securing the internal structure 20 to the bottom surface 31 of the frame 30. A positioning boss 201 for positioning relative to the frame 30 is formed on the bottom surface 21 of the internal structure 20, and a positioning boss hole 301 for inserting the positioning boss 201 is formed on the bottom surface 31 of the frame 30. When the internal structure 20 and the frame 30 are assembled such that the bottom surface 21 of the internal structure 20 is supported by the bottom surface 31 of the frame 30, the positioning boss 201 of the internal structure 20 and the positioning boss hole 301 of the frame 30 engage with each other. The bottom surface 31 of the frame 30 and the bottom surface 21 of the internal structure 20 are fastened together by the screws 40, thereby securing the internal structure 20 and the frame 30 to the bottom portion of the imaging device 10.

[0041] Now, refer to FIG. 4A to FIG. 4E and FIG. 5A and FIG. 5B Describes the connection between the frame 30 and the internal structure 20 in the upper part of the imaging device 10. FIG. 4A It is a schematic cross-sectional view of the frame 30 and the internal structure 20 taken along a section perpendicular to the front-back direction.

[0042] FIG. 4B It is by FIG. 4A An enlarged view of the portion indicated by B near the first limiting portion 401 on the left side surface of the imaging device 10. FIG. 4C It is by FIG. 4A An enlarged view of the portion indicated by C near the second limiting portion 402 on the right surface of the imaging device 10.

[0043] FIG. 4D It is along FIG. 4B A schematic cross-sectional view of the first restricted portion 401 cut from the AA section shown. FIG. 4E It is along FIG. 4C A schematic cross-sectional view of the second limiting portion 402 cut from the BB section shown.

[0044] The frame 30 and the internal structure 20 are joined to each other near the left and right side surfaces of the upper portion of the image forming apparatus 10. The image forming apparatus 10 includes a first restriction portion 401 and a second restriction portion 402 as a plurality of restriction portions for restricting relative movement between the internal structure 20 and the frame 30 in the up-and-down direction perpendicular to the bottom surface 31. According to the embodiment, the frame 30 has the first restriction portion 401 and the second restriction portion 402. The first restriction portion 401 and the second restriction portion 402 are provided near the left and right sides of the side surface 32 of the frame 30 so that the distance between the first restriction portion 401 and the second restriction portion 402 in the direction parallel to the bottom surface 31 can be as large as possible. As shown in FIG. 4A D1 indicates the distance in the vertical direction between the position of the first restriction portion 401 or the second restriction portion 402 and the position of the bottom surface 31 of the frame 30, and D2 indicates the distance in the vertical direction between the position of the first restriction portion 401 or the second restriction portion 402 and the position of the upper end portion 33 of the side surface 32 of the frame 30. The first restriction portion 401 and the second restriction portion 402 are provided so that the distance D2 is smaller than the distance D1. Note that although the positional relationship between the bottom surface, the upper end portion, and the restriction portion has been described here, the distance from the end portion on the side opposite to the bottom surface of the side surface to each of the restriction portions only needs to be smaller than the distance from the bottom surface to each of the restriction portions.

[0045] The first restriction portion 401 and the second restriction portion 402 restrict relative movement between the internal structure 20 and the frame 30 in the up-and-down direction by joining the internal structure 20 and the frame 30 in the up-and-down direction. Note that the up-and-down direction here refers to the direction perpendicular to the bottom surface of the frame 30. In FIG. 4A FIG. 4B and FIG. 4C , the up-and-down direction of the sheet surface corresponds to the up-and-down direction of the frame 30, the left-and-right direction of the sheet surface corresponds to the front-and-rear direction of the frame 30, and the direction perpendicular to the sheet surface corresponds to the left-and-right direction of the frame 30. In FIG. 4D and FIG. 4E , the up-and-down direction of the sheet surface corresponds to the up-and-down direction of the frame 30, the left-and-right direction of the sheet surface corresponds to the front-and-rear direction of the frame 30, and the direction perpendicular to the sheet surface corresponds to the left-and-right direction of the frame 30.

[0046] In FIG. 4A , the outermost U-shaped frame member is the frame 30, and the structure inside the frame constitutes the internal structure 20.

[0047] As shown in FIG. 4B ​As shown, the first contact portion 202 located on the internal structure 20 and the second contact portion 302 located on the frame 30 are in vertical contact with each other at the first limiting portion 401 located on the upper part of the left side surface of the imaging device 10. Here, the vertical direction is perpendicular to the bottom surface of the imaging device 10. In this way, the relative movement between the frame 30 and the internal structure 20 in the direction perpendicular to the bottom surface 31 is restricted. Note that in FIG. 4B In the reference numeral 210, a component as part of the internal structure 20 includes a user operation button, a light source for illuminating the button, and a light guide for directing light from the light source. Reference numeral 211 refers to a part of the main frame as part of the internal structure. Reference numeral 212 indicates screw holes associated with the positioning and fixing of the internal structure 20, and reference numeral 213 indicates a positioning boss. Reference numeral 214 refers to a component for holding wiring at a part of the internal structure.

[0048] like FIG. 4C As shown, the third contact portion 203 disposed on the internal structure 20 and the fourth contact portion 303 disposed on the frame 30 are in vertical contact with each other in the second limiting portion 402 disposed on the upper portion of the right side surface of the imaging device 10. The second limiting portion 402 has a recessed fourth contact portion 303, and the third contact portion 203, as a protruding portion, is adapted to the fourth contact portion 303. In this way, the relative movement between the frame 30 and the internal structure 20 in the direction perpendicular to the bottom surface 31 is restricted. It should be noted that in FIG. 4C In the figures, reference numeral 215 indicates a part of the main frame that is a component of the internal structure 20. Reference numeral 216 indicates a component for positioning the processing box that serves as the imaging unit. Reference numeral 217 indicates a gear associated with the drive of the photosensitive drum 1. In the first limiting portion 401 and the second limiting portion 402, a part of the internal structure 20 is configured to engage with a part of the frame 30 from above in the vertical direction.

[0049] like FIG. 4DAs shown, the first contact portion 202 of the first restriction portion 401 is formed by a member having a rectangular cross section and extending along the side surface 32 of the frame 30 in a direction (front-rear direction, a direction parallel to the bottom surface 31) perpendicular to the up-down direction (a direction perpendicular to the bottom surface 31) of the frame 30. The second contact portion 302 of the first restriction portion 401 is formed by one or more members arranged at intervals along the side surface 32 of the frame 30 in the direction (in the front-rear direction) perpendicular to the up-down direction of the frame 30 and having a rectangular cross section and a smaller size than the first contact portion 202. More specifically, the length of the second contact portion 302 in the front-rear direction is smaller than the length of the first contact portion 202 in the front-rear direction. As shown, the first contact portion 202 and the second contact portion 302 are in contact with each other in the up-down direction. In the description of the embodiment, two second contact portions 302 are provided, but the number of second contact portions 302 is not limited to two when more than one contact portion is provided. FIG. 4D As shown, the first contact portion 202 and the second contact portion 302 are in contact with each other in the up-down direction. In the description of the embodiment, two second contact portions 302 are provided, but the number of second contact portions 302 is not limited to two when more than one contact portion is provided.

[0050] As shown, the first contact portion 202 and the second contact portion 302 are in contact with each other in the up-down direction. In the description of the embodiment, two second contact portions 302 are provided, but the number of second contact portions 302 is not limited to two when more than one contact portion is provided. FIG. 4E As shown, the third contact portion 203 of the second restriction portion 402 is formed by a member having a rectangular cross section and extending along the side surface 32 of the frame 30 in a direction (front-rear direction, a direction parallel to the bottom surface 31) perpendicular to the up-down direction (a direction perpendicular to the bottom surface 31) of the frame 30. The fourth contact portion 303 of the second restriction portion 402 is formed by one or more members arranged at intervals along the side surface 32 of the frame 30 in the direction (in the front-rear direction) perpendicular to the up-down direction of the frame 30 and having a rectangular cross section and a smaller size than the third contact portion 203. As shown, the third contact portion 203 and the fourth contact portion 303 are in contact with each other in the up-down direction. In the description of the embodiment, two fourth contact portions 303 are provided, but the number of fourth contact portions is not limited to two when more than one contact portion is provided. FIG. 4E As shown, the first contact portion 202 and the second contact portion 302 are in contact with each other in the up-down direction. In the description of the embodiment, two second contact portions 302 are provided, but the number of second contact portions 302 is not limited to two when more than one contact portion is provided.

[0051] Note that the first and second restricting portions 401 and 402 can have any other structure than the above-described example. The first and second restricting portions 401 and 402 can include at least one of a member having a rectangular cross section and extending in the front-rear direction and one or more members arranged at intervals and having a rectangular cross section along the side surface 32 of the frame 30. More specifically, the first and third contact portions 202 and 203 can include one or more members arranged at intervals in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30 and having a rectangular cross section. The second and fourth contact portions 302 and 303 can include a member having a rectangular cross section and extending in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30. All the contact portions can include one or more members arranged at intervals in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30 and having a rectangular cross section. All the contact portions can include a member having a rectangular cross section and extending in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30. The cross-sectional shape is not limited to a rectangular shape as long as the first and second contact portions 202 and 302 can contact each other in the up-down direction and the third and fourth contact portions 203 and 303 can contact each other in the up-down direction.

[0052] The functions of the first to fourth contact portions will be described with reference to FIG. 5A and FIG. 5B The functions of the first to fourth contact portions will be described with reference to

[0053] FIG. 5A and FIG. 5B is a diagram showing a case where a deformation-causing force acts on the entire apparatus. In FIG. 5A , the apparatus is installed with the right front portion of the apparatus in a raised state. This can occur when the image forming apparatus 10 is installed on a mounting surface having a step 50 and the right rear portion of the image forming apparatus 10 is placed on the step 50. In this state, a force that can deform the right front portion of the image forming apparatus 10 downward can act on the image forming apparatus 10. When the image forming apparatus 10 is used in a deformed state as in FIG. 5A , the relative positions between the optical unit 18 and the photosensitive drum 1 can be offset, which can cause image degradation.

[0054] In contrast, in the image forming apparatus 10 according to the first embodiment, when the right front portion of the internal structure 20 is about to be deformed downward, for example, the third contact portion 203 of the internal structure 20 contacts the fourth contact portion 303 of the frame 30, and the internal structure 20 is supported due to the rigidity of the frame 30. In this way, the relative movement between the internal structure 20 and the frame 30 in the vertical direction is restricted, and the deformation of the internal structure 20 is restricted. When the right front portion of the frame 30 is about to be deformed downward, the second contact portion 302 of the frame 30 starts to move upward due to the rigidity of the frame 30. However, the second contact portion 302 contacts the first contact portion 202 of the internal structure 20, so that the relative movement between the internal structure 20 and the frame 30 in the vertical direction is restricted, and thus the deformation of the frame 30 is restricted. Therefore, when the image forming apparatus 10 is installed while the right front portion of the image forming apparatus 10 is in the raised state, the deformation of the right front portion of the frame 30 and the internal structure 20 can be restricted as shown in FIG. 5B .

[0055] Now, the engagement between the frame 30 and the internal structure 20 on the front side of the image forming apparatus 10 will be described with reference to FIG. 6 , FIG. 7A and FIG. 7B . The frame 30 and the internal structure 20 engage with each other near the center of the image forming apparatus 10 on the front side.

[0056] FIG. 6 is a perspective view of the internal structure 20 and the frame 30 viewed from the back and the bottom. For ease of description, only a portion of the upper portion of the internal structure 20 and the frame 30 is shown.

[0057] The image forming apparatus 10 includes a third restriction portion 403 as a restriction portion for restricting the relative movement between the internal structure 20 and the frame 30 in the up-and-down direction perpendicular to the bottom surface 31. The third restriction portion 403 is provided so that the third restriction portion 403 contacts the upper end portion 33 (see FIG. 4AThe distance in the vertical direction between the third restriction portion 403 and the bottom surface 31 of the frame 30 is smaller than the distance in the vertical direction between the fourth restriction portion 404 and the bottom surface 31 of the frame 30. In the fourth restriction portion 404, the seventh contact portion 207 provided at the inner structure 20 and the eighth contact portion 307 provided at the frame 30 contact each other in the up-down direction. Here, the seventh contact portion 207 is a hole provided on the front side of the inner structure 20, and the eighth contact portion 307 is a protrusion provided on the front side of the frame 30. Here, the engagement arrangement between the hole and the protrusion is shown as an example, but the engagement arrangement can be any arrangement other than the above-described example, as long as the arrangement allows the members to contact each other in the up-down direction to restrict the positions of the frame 30 and the inner structure 20 from shifting from each other in the up-down direction. The fourth restriction portion 404 restricts the relative movement between the inner structure 20 and the frame 30 in the up-down direction by the engagement structure.

[0058] The functions of the fifth to eighth contact portions will be described with reference to FIG. 7A and FIG. 7B

[0059] FIG. 7A and FIG. 7B are diagrams showing a case where a deformation-causing force acts on the entire apparatus. FIG. 7A A case where the apparatus is installed with the front portion thereof in a raised state is shown. This can occur when the image forming apparatus 10 is installed on an installation surface having a step 70 and the center portion of the image forming apparatus 10 is arranged on the step 70. In this state, a force that can deform the front portion of the image forming apparatus 10 downward can act on the image forming apparatus 10. When the image forming apparatus 10 is used in the deformed state as in FIG. 7A , the relative positions between the optical unit 18 and the photosensitive drum 1 can shift, which can cause image degradation.

[0060] In contrast, in the image forming apparatus 10 according to the first embodiment, when the front portion of the inner structure 20 is about to be deformed downward, the fifth contact portion 204 of the inner structure 20 contacts the sixth contact portion 304 of the frame 30, so that the relative movement between the inner structure 20 and the frame 30 in the vertical direction is restricted. In this way, the deformation of the inner structure 20 is restricted. When the front portion of the frame 30 is about to be deformed downward, the fifth contact portion 204 of the inner structure 20 and the sixth contact portion 304 of the frame 30 contact each other, so that the relative movement between the inner structure 20 and the frame 30 in the vertical direction is restricted. In this way, the deformation of the frame 30 is restricted. Therefore, as shown in FIG. 7B , it is possible to restrict the front portions of the frame 30 and the inner structure 20 from being deformed downward.

[0061] ​Note that the frame 30 and the internal structure 20 are illustrated as being joined in the up-down direction near the front side of the image forming apparatus 10, but the same joining arrangement can also be provided near the rear side of the image forming apparatus 10. In this way, it is possible to ensure that it is possible to limit deformation of the frame 30 and the internal structure 20.

[0062] As described above, according to the first embodiment, the internal structure 20 is fixed to the bottom surface 31 of the frame 30 by the screws 40, and the limiting portions 401, 402, and 403 for limiting relative movement between the frame 30 and the internal structure 20 in a direction perpendicular to the bottom surface 31 are provided at the side surfaces 32 extending upward from the bottom surface 31 of the frame 30. In this way, using the rigidity of both the frame 30 and the internal structure 20 to resist the external deformation-causing force acting on the image forming apparatus 10, it is possible to limit deformation of the image forming apparatus 10. Therefore, when the upper cover 35 is not formed to have high rigidity, it is possible to ensure the rigidity of the image forming apparatus 10 as a whole. In this way, it is possible to ensure the rigidity of the entire image forming apparatus 10 including the internal structure without using a plurality of frames having high rigidity, which limits an increase in cost and size.

[0063] The foregoing description sets forth examples of the present application and is not intended to limit the present application. For example, according to the first embodiment, the first and second restriction portions 401 and 402 for restricting the relative movement between the frame 30 and the internal structure 20 in the vertical direction are linearly provided along the left and right sides of the side surface 32 of the frame 30, but an engagement arrangement including a hole and a protrusion similar to the third restriction portion 403 can be provided. One third restriction portion 403 is provided in the center of the image forming apparatus 10 in an exemplary manner, but the restriction portions can be provided in a plurality of prescribed intervals. According to the first embodiment, a plurality of restriction portions are provided, but only one restriction portion can be provided. The restriction portion can be any arrangement other than the engagement arrangement between the contact portion provided at the frame 30 and the contact portion provided at the internal structure 20 or the engagement arrangement between the protrusion provided at the frame 30 and the hole provided at the internal structure 20. The contact portion forming the restriction portion is provided at both the frame 30 and the internal structure 20, but the contact portion can be provided at at least one of the frame 30 and the internal structure 20. According to the first embodiment, the side surface 32 of the frame 30 includes front, rear, left, and right planes and curved surfaces smoothly connecting these planes in an exemplary manner. However, the frame 30 according to the present application can have any other structure as long as the frame 30 has a bottom surface and a side surface extending upward from the bottom surface and the surfaces other than the upper opening are connected to surround the internal structure 20. For example, the frame 30 can have a bottomed cylindrical shape having a circular bottom surface and a tubular side surface extending upward. The side surface extending upward from the bottom surface does not necessarily extend upward at a right angle with respect to the bottom surface. When the present application is applied to an image forming apparatus having a bottomed cylindrical frame, a plurality of restriction portions can be provided near the intersection between a straight line passing through the central axis of the cylinder and parallel to the bottom surface and the side surface. In this manner, the interval of the plurality of restriction portions in the direction parallel to the bottom surface can be as large as possible.

[0064] Second Embodiment

[0065] According to the first embodiment, the engagement portion of the internal structure 20 contacts the engagement portion of the frame 30 from above in the engagement arrangement between the frame 30 and the internal structure 20 at the upper portion of the image forming apparatus 10 in an exemplary manner. However, the arrangement is not intended to limit the present application.

[0066] FIG. 8A is a schematic cross-sectional view taken along a front-rear cross section perpendicular to the frame 30 and the internal structure 20. FIG. 8B is an enlarged view of a portion indicated by B near the first restriction portion 401 on the left side surface of the image forming apparatus 10 in FIG. 8A FIG. 8C is an enlarged view of a portion indicated by B near the first restriction portion 401 on the left side surface of the image forming apparatus 10 in FIG. 8A ​An enlarged view of a portion indicated by C near the second regulating portion 402 on the right side surface of the image forming apparatus 10 in FIG. 1. FIG. 8D is a schematic cross-sectional view of the first regulating portion 401 taken along FIG. 8B FIG. 8E is a schematic cross-sectional view of the second regulating portion 402 taken along FIG. 8C FIG. 8A , FIG. 8B and FIG. 8C In FIG. 8D and FIG. 8E , the up-and-down direction of the sheet surface corresponds to the up-and-down direction of the frame 30, the left-and-right direction of the sheet surface corresponds to the front-and-rear direction of the frame 30, and the direction perpendicular to the sheet surface corresponds to the left-and-right direction of the frame 30.

[0067] In FIG. 8A , the outermost upward U-shaped frame is the frame 30, and the structure inside the frame constitutes the internal structure 20. As shown in FIG. 8A , D1 indicates a distance in the vertical direction between the position of the first regulating portion 401 or the second regulating portion 402 and the position of the bottom surface 31 of the frame 30, and D2 indicates a distance in the vertical direction between the position of the first regulating portion 401 or the second regulating portion 402 and the position of the upper end portion 33 of the side surface 32 of the frame 30. The first regulating portion 401 and the second regulating portion 402 are provided so that the distance D2 is smaller than the distance D1. Note that, although the positional relationship between the bottom surface, the upper end portion, and the regulating portion has been described, the distance from the end portion of the side surface on the side opposite to the bottom surface to each of the regulating portions only needs to be smaller than the distance from the bottom surface to each of the regulating portions.

[0068] As shown in FIG. 8B , in the first regulating portion 401 provided at the upper portion of the left side surface of the apparatus, the first contact portion 202 provided at the internal structure 20 and the second contact portion 302 provided at the frame 30 are in contact with each other in the up-and-down direction. Note that, FIG. 8B the reference numerals 210, 211, 212, 214 indicating the components of the internal structure 20 in FIG. 4B indicate the same components in

[0069] As shown in FIG. 8C ​​As shown, in the second restriction portion 402 provided at the upper portion of the right side surface of the device, the third contact portion 203 provided at the internal structure 20 and the fourth contact portion 303 provided at the frame 30 contact each other in the up-down direction. Note that, FIG. 8C the reference numerals 215, 216, and 217 that denote the components of the internal structure 20 in FIG. 4C denote the same components.

[0070] As shown in FIG. 8D , the second contact portion 302 of the first restriction portion 401 is formed by a member that has a rectangular cross section and extends along the side surface 32 of the frame 30 in a direction (the front-rear direction, a direction parallel to the bottom surface 31) perpendicular to the up-down direction (a direction perpendicular to the bottom surface 31) of the frame 30. The first contact portion 202 of the first restriction portion 401 is formed by one or more members that are arranged at intervals in the direction (in the front-rear direction) perpendicular to the up-down direction of the frame 30 along the side surface 32 of the frame 30 and have a rectangular cross section and have a smaller size than the second contact portion 302. In other words, the length of the first contact portion 202 in the front-rear direction is greater than the length of the second contact portion 302. As shown in FIG. 8D , the first contact portion 202 and the second contact portion 302 contact each other in the up-down direction. In the description of the embodiment, two first contact portions 202 are provided in an exemplary manner, but the number of contact portions can be two or more.

[0071] As shown in FIG. 8E , the fourth contact portion 303 of the second restriction portion 402 is formed by a member that has a rectangular cross section and extends along the side surface 32 of the frame 30 in a direction (in the front-rear direction) perpendicular to the up-down direction of the frame 30. The third contact portion 203 of the second restriction portion 402 is formed by one or more members that are arranged at intervals in the direction (in the front-rear direction) perpendicular to the up-down direction of the frame 30 along the side surface 32 of the frame 30 and have a rectangular cross section and have a smaller size than the fourth contact portion 303. As shown in FIG. 8E , the third contact portion 203 and the fourth contact portion 303 contact each other in the up-down direction. In the description of the embodiment, two third contact portions 203 are provided in an exemplary manner, but the number of contact portions is not limited to two.

[0072] Note that the first and second restricting portions 401 and 402 can have other structures than the above-described examples. The first and second restricting portions 401 and 402 can include at least one of a member having a rectangular cross section and extending in the front-rear direction along the side surface 32 of the frame 30 and one or more members arranged at intervals and having a rectangular cross section. More specifically, the second and fourth contact portions 302 and 303 can include one or more members arranged at intervals in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30. The first and third contact portions 202 and 203 can include a member having a rectangular cross section and extending in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30. All the contact portions can include one or more members arranged at intervals in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30 and having a rectangular cross section. All the contact portions can include a member having a rectangular cross section and extending in a direction perpendicular to the up-down direction of the frame 30 (in the front-rear direction) along the side surface 32 of the frame 30. The cross-sectional shape is not limited to a rectangular shape, as long as the first and second contact portions 202 and 302 can be in contact with each other in the up-down direction and the third and fourth contact portions 203 and 303 can be in contact with each other in the up-down direction.

[0073] In contrast to the first embodiment, according to the second embodiment, in the first and second restricting portions 401 and 402, a portion of the frame 30 is configured to engage with a portion of the internal structure 20 from above in the up-down direction. Note that, also according to the second embodiment, at least one of the first and second restricting portions 401 and 402 can have the same recessed structure as the second restricting portion 402 according to the first embodiment. In this case, in contrast to the second restricting portion 402 according to the first embodiment, the fourth contact portion 303 according to the second embodiment can be formed to have a downwardly recessed structure, and the third contact portion 203 can be formed to fit into the fourth contact portion 303 as a recessed structure from below.

[0074] When, for example, the right front portion of the internal structure 20 is about to be deformed downward, the first and second restriction portions 401 and 402 allow the second contact portion 302 of the frame 30 to contact the first contact portion 202, which would otherwise move upward due to the rigidity of the internal structure 20. In this way, relative movement between the internal structure 20 and the frame 30 in the vertical direction can be restricted, so that deformation of the internal structure 20 can be restricted. When the right front portion of the frame 30 is about to be deformed downward, the third and fourth contact portions 203 and 303 contact each other, so that the frame 30 is supported by the internal structure 20. In this way, relative movement between the internal structure 20 and the frame 30 in the vertical direction is restricted, so that deformation of the frame 30 can be restricted. Thus, when the device is installed while the right front portion of the device is in the raised state, deformation of the right front portion of the frame 30 and the internal structure 20 downward can be restricted, as FIG. 5B shown.

[0075] As described above, according to the second embodiment, the internal structure 20 is fixed to the bottom surface 31 of the frame 30 by the screws 40, and the first and second restriction portions 401 and 402 for restricting relative movement between the frame 30 and the internal structure 20 in a direction perpendicular to the bottom surface 31 are provided at the side surface 32 extending upward from the bottom surface 31 of the frame 30. In this way, using the rigidity of both the frame 30 and the internal structure 20 to resist external forces causing deformation acting on the image forming device 10, deformation of the image forming device 10 can be restricted. Thus, similarly to the first embodiment, the total rigidity of the image forming device 10 including the internal structure 20 can be ensured without using a plurality of frames having high rigidity, which can restrict an increase in cost and size.

[0076] While the present application has been described with reference to exemplary embodiments, it is to be understood that the application is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. An image forming apparatus comprising: a resin frame molded by a resin, having (i) a bottom portion and (ii) a side portion integrally formed with the bottom portion so as to extend upward from the bottom portion, the frame being located outside the image forming apparatus; an internal structure capable of supporting an image forming portion for forming an image on a recording material; and a screw for fixing the internal structure to the bottom portion of the frame, wherein the image forming portion includes a photosensitive member and a developing unit configured to develop a latent image formed on the photosensitive member, wherein the side portion is provided so as to surround the internal structure, and the side portion includes a first surface located on a first side of the photosensitive member in a longitudinal direction, a second surface located on a second side opposite to the first side in the longitudinal direction, and a third surface located on a third side provided between the first side and the second side in the longitudinal direction, wherein the first surface and the internal structure form a first restriction portion configured to restrict relative movement in a vertical direction between the internal structure and the frame, wherein the second surface and the internal structure form a second restriction portion configured to restrict relative movement in the vertical direction between the internal structure and the frame, wherein the third surface and the internal structure form a third restriction portion configured to restrict relative movement in the vertical direction between the internal structure and the frame, and the third restriction portion includes a hole and a protrusion fitted in the hole.

2. The imaging device of claim 1, wherein, The hole is provided at the internal structure, and the protrusion is provided at the third surface.

3. The imaging device of claim 1, wherein, The first restriction portion includes a first contact portion provided at the internal structure and a second contact portion provided at the first surface, the first contact portion and the second contact portion being in contact with each other in the vertical direction, and wherein the second restriction portion includes a third contact portion provided at the internal structure and a fourth contact portion provided at the second surface, the third contact portion and the fourth contact portion being in contact with each other in the vertical direction.

4. The imaging device of claim 3, wherein, The first contact portion engages with the second contact portion from above, and the third contact portion engages with the fourth contact portion from above.

5. The imaging device of claim 3, wherein, The second contact portion engages with the first contact portion from above, and the fourth contact portion engages with the third contact portion from above.

6. The imaging device of claim 1, wherein, The first surface and the internal structure form a plurality of first restriction portions.

7. The imaging device of claim 6, wherein, The plurality of first restriction portions are provided at a maximum interval within an allowable range in a direction parallel to the bottom portion.

8. The imaging device of claim 1, wherein, The image forming portion is a process cartridge capable of being attached to and detached from the image forming apparatus.

9. The image forming apparatus according to any one of claims 1 to 8, wherein a distance in the vertical direction between the first restriction portion and an upper end portion of the side portion is smaller than a distance in the vertical direction between the first restriction portion and the bottom portion, wherein a distance in the vertical direction between the second restriction portion and the upper end portion of the side portion is smaller than a distance in the vertical direction between the second restriction portion and the bottom portion, and wherein a distance in the vertical direction between the third restriction portion and the upper end portion of the side portion is smaller than a distance in the vertical direction between the third restriction portion and the bottom portion.

Images