Image forming apparatus

Abstract

To provide an image forming apparatus that prevents attachment in a deformed state of placement members having placed thereon optical scanning means for forming electrostatic latent images on photoreceptors.SOLUTION: An image forming apparatus has: optical scanning means that forms electrostatic latent images on photoreceptors; placement members that have the optical scanning means placed thereon; a first support member that has the placement members fixed thereto and supports the placement members; a second support member that faces the first support member and supports the placement members with the first support member; and a connection member that includes a first surface fixed to the second support member and a second surface bent at a substantially right angle to the first surface and fixed to the placement members, and connects the second support member and the placement members to each other.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an image forming apparatus such as a copying machine or a printer using an electrophotographic method or an electrostatic recording method.

Background Art

[0002] Conventionally, in an image forming apparatus using an electrophotographic method or an electrostatic recording method, as shown in Patent Document 1, an optical scanning device for forming an electrostatic latent image on a photoreceptor drum is placed on a stay provided on a frame of the image forming apparatus. The stay for placing the optical scanning device has two mounting surfaces bent at right angles to the mounting surface of the optical scanning device in the opposing direction, and is fastened and fixed to front and rear side plates extending vertically from an installation surface constituting the frame of the image forming apparatus with screws.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the stay for placing the optical scanning device is fastened and fixed to the front and rear side plates in this way, the stay may be deformed.

[0005] The distance between the front side plate and the rear side plate deviates from the design value by a certain amount due to dimensional variations including other components during the frame assembly.

[0006] Similarly, the distance between the mounting surfaces of the stay, which is fastened and fixed to the frame, varies by a certain amount due to manufacturing variations.

[0007] Generally, considering the ease of assembly, the distance between the front and rear side plates is designed to be larger than the distance between the mounting surfaces of the stay.

[0008] As described above, when the stays are fastened to the front and rear side plates with screws while there is a gap between the front and rear side plates and the stays, the opposing mounting surfaces 91b and 91c of the stay 91 are pulled towards the front side plate 92 and the rear side plate 93, respectively, causing the mounting surface 91a of the optical scanning device to deform and changing the distance between the photoreceptor and the optical scanning device.

[0009] In particular, in image forming apparatuses that prioritize image quality, some have reduced the spot diameter of the light beam that forms an image on the photoreceptor. However, reducing the spot diameter results in a shallower depth, and the difference in distance between the optical scanning device and the photoreceptor has a greater impact on image quality.

[0010] The present invention has been made in view of the above circumstances, and aims to provide an image forming apparatus that prevents a mounting member on which an optical scanning means for forming an electrostatic latent image on a photoreceptor is mounted in a deformed state. [Means for solving the problem]

[0011] To achieve the above objective, the present invention provides an optical scanning means for forming an electrostatic latent image on a photoreceptor; a mounting member on which the optical scanning means is mounted; a first support member to which the mounting member is fixed and which supports the mounting member; a second support member facing the first support member and supporting the mounting member together with the first support member; and a connecting member having a first surface fixed to the second support member and a second surface bent at approximately a right angle to the first surface and fixed to the mounting member, and connecting the second support member and the mounting member. Furthermore, the first surface of the connecting member is a plane extending in a direction perpendicular to the vertical direction. It is characterized by the following: [Effects of the Invention]

[0012] According to the present invention, it is possible to provide an image forming apparatus that prevents a mounting member on which an optical scanning means for forming an electrostatic latent image on a photoreceptor is mounted in a deformed state. [Brief explanation of the drawing]

[0013] [Figure 1]This is a schematic front cross-sectional view of an image forming apparatus according to an embodiment of the present invention. [Figure 2] This is a perspective view of the frame of an image forming apparatus according to an embodiment of the present invention. [Figure 3] This is a perspective view of the frame body as seen from the rear, showing the frame body with the stays and intermediate members arranged according to an embodiment of the present invention. [Figure 4] This is a perspective view of the frame body as seen from the front, showing the frame body according to an embodiment of the present invention with the stays and intermediate members arranged on it. [Figure 5] This is an exploded perspective view of a frame body showing a configuration in which a stay and an intermediate member are fastened and fixed to the frame body according to an embodiment of the present invention. [Figure 6] This is an explanatory diagram illustrating the configuration and assembly procedure of the stay and intermediate member according to the first embodiment of the present invention. [Figure 7] This is an explanatory diagram illustrating the configuration and assembly procedure of the stay and intermediate member according to a second embodiment of the present invention. [Figure 8] This is an explanatory diagram illustrating the configuration and assembly procedure of a stay and intermediate member according to a third embodiment of the present invention. [Figure 9] This is an explanatory diagram illustrating the configuration and assembly procedure of a stay and intermediate member according to a fourth embodiment of the present invention. [Figure 10] This is an explanatory diagram illustrating the configuration and assembly procedure of a stay and intermediate member according to a fifth embodiment of the present invention. [Figure 11] This is an explanatory diagram illustrating the conventional assembly method of the stay. [Modes for carrying out the invention]

[0014] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the components described in the following embodiments are merely illustrative, and the configuration, function, dimensions, materials, shape, relative arrangement, and other conditions of the apparatus to which the present invention is applied can be modified or changed as appropriate without departing from the spirit of the invention, and the invention is not limited to the following embodiments.

[0015] FIG. 1 is a schematic front cross-sectional view of an image forming apparatus according to an embodiment of the present invention.

[0016] In FIG. 1, the image forming apparatus 100 has a document reading unit 8, an image forming unit 10, and a paper feeding unit 9.

[0017] The document reading unit 8 reads an image of a document placed on the document table glass. The document reading unit 8 has a line sensor 81, lenses 82, and mirrors 83, 84, 85, and a platen 86. The document placed on the document table glass 87 is pressed by the platen 86. When reading an image of the document, the document is irradiated with light. The reflected light from the document is imaged on the line sensor 81 by the lens 82 via the mirrors 85, 84, 83. The line sensor 81 converts the reflected light from the document into an electrical signal. The electrical signal is input as image information to a control unit (not shown).

[0018] The control unit controls the laser drive units of the optical scanning devices 1a, 1b, 1c, 1d, which are optical scanning means described later, according to the image information, and outputs a light beam (laser beam) modulated according to the image information from the optical scanning device 1.

[0019] The image forming unit 10 has four image forming stations Pa, Pb, Pc, and Pd, an intermediate transfer belt 61, and a fixing device 7. The image forming stations Pa, Pb, Pc, Pd form cyan, magenta, yellow, and black images, respectively. Each of the image forming stations Pa, Pb, Pc, Pd has a photosensitive drum 2a, 2b, 2c, 2d as an image carrier. Note that the rotational axis direction of the photosensitive drums 2a, 2b, 2c, 2d is the front-rear direction of the image forming apparatus 100.

[0020] Around each of the photoreceptor drums 2a, 2b, 2c, and 2d, in order along the rotational direction of the photoreceptor drums 2a, 2b, 2c, and 2d, are the charging devices 3a, 3b, 3c, and 3d, the optical scanning devices 1a, 1b, 1c, and 1d, the developing devices 5a, 5b, 5c, and 5d, the primary transfer devices 6a, 6b, 6c, and 6d, and the drum cleaning devices 4a, 4b, 4c, and 4d.

[0021] The charging devices 3a, 3b, 3c, and 3d uniformly charge the surfaces of the photoreceptor drums 2a, 2b, 2c, and 2d.

[0022] Optical scanning devices 1a, 1b, 1c, and 1d irradiate the surfaces of uniformly charged photoreceptor drums 2a, 2b, 2c, and 2d with light beams modulated according to the image information of each color, thereby forming electrostatic latent images on the surfaces of the photoreceptor drums 2a, 2b, 2c, and 2d. Optical scanning devices 1a, 1b, 1c, and 1d are equipped with pre-adjusted optical scanning devices using a special tool to adjust the rotational irradiation position relative to the photoreceptor drums 2a, 2b, 2c, and 2d, as well as the misalignment with the busbars of the photoreceptor drums 2a, 2b, 2c, and 2d, and to adjust the focus so that the light beams are imaged on the surfaces of the photoreceptor drums 2a, 2b, 2c, and 2d.

[0023] The developing units 5a, 5b, 5c, and 5d develop the electrostatic latent images formed on the surface of the photoreceptor drums 2a, 2b, 2c, and 2d with their respective colored developers (toners) to form toner images of their respective colors.

[0024] The primary transfer devices 6a, 6b, 6c, and 6d transfer the toner image on the surface of the photoreceptor drum 2 to the intermediate transfer belt 61.

[0025] The drum cleaning devices 4a, 4b, 4c, and 4d remove any toner remaining on the photoreceptor drums 2a, 2b, 2c, and 2d after transfer.

[0026] The developing units 5a, 5b, 5c, and 5d each have developer containers 51a, 51b, 51c, and 51d, which contain toner of their respective colors. The developer containers 51a, 51b, 51c, and 51d are cylindrical developer cartridges that can be attached to and removed from the main body of the image forming apparatus 100. The developer containers 51a, 51b, 51c, and 51d replenish toner to the developing units 5a, 5b, 5c, and 5d.

[0027] The photoreceptor drums 2a, 2b, 2c, and 2d, the charging devices 3a, 3b, 3c, and 3d, and the drum cleaning devices 4a, 4b, 4c, and 4d are each integrated to form a process cartridge that can be attached to and detached from the main body of the image forming apparatus 100.

[0028] An endless belt-shaped intermediate transfer belt 61 is positioned beneath the photoreceptor drums 2a, 2b, 2c, and 2d. The intermediate transfer belt 61 contacts the four photoreceptor drums 2a, 2b, 2c, and 2d and passes through the four image forming stations Pa, Pb, Pc, and Pd. The intermediate transfer belt 61 is stretched over the drive roller 62 and the driven rollers 63 and 65. A belt cleaning device 64 is positioned opposite the driven roller 63. The belt cleaning device 64 can move in and out of the intermediate transfer belt 61. The belt cleaning device 64 removes toner remaining on the intermediate transfer belt 61 after secondary transfer.

[0029] The paper feeding unit 9 has a manual feed tray 70 and paper feed cassettes 78 and 79 that store sheet material. The direction in which the paper feed cassettes 78 and 79 are pulled out is from the rear to the front of the image forming apparatus 100. The paper feeding unit 9 transports the sheet material fed from the manual feed tray 70, paper feed cassette 78, or paper feed cassette 79 to the secondary transfer unit ST using a registration roller 73, in time with the toner image on the intermediate transfer belt 61. The secondary transfer unit ST is formed by a driven roller 65 and a secondary transfer roller (transfer device) 66. In the secondary transfer unit ST, the toner image on the intermediate transfer belt 61 is transferred to the sheet material.

[0030] The fuser unit 7 has a fuser roller pair 74. The fuser roller pair 74 heats and pressurizes the sheet material onto which the toner image has been transferred, fixing the toner image to the sheet material and forming a full-color image on the sheet material. The sheet material on which the full-color image has been formed is conveyed by the outlet roller pair 75 of the fuser unit 7 and discharged onto the discharge tray 77 by the discharge roller pair 76.

[0031] Figure 2 is a perspective view of the frame 20 of the image forming apparatus 100 shown in Figure 1, with the various units removed.

[0032] In Figure 2, the frame 20 is a support frame that supports various units within the image forming apparatus 100, such as the photoreceptor drums 2a, 2b, 2c, 2d, the charging devices 3a, 3b, 3c, 3d, and the developing devices 5a, 5b, 5c, 5d.

[0033] The base plate 21 is made by combining and fixing two steel plates, each with vertical walls created by drawing or bending processes around its entire circumference.

[0034] The bottom of the base plate 21 is equipped with casters (not shown) at its four corners, which allow the image forming apparatus 100 to be moved.

[0035] Support columns 22a and 23a are erected at the two corners of the upper surface of the front bottom plate 21 of the frame 20, and the contact points with the bottom plate 21 are joined by welding.

[0036] Support columns 22b and 23b are joined to support columns 22a and 23a by welding in a manner that extends them upward.

[0037] A front plate 24, serving as a first support member, is positioned on the upper front of the frame 20 and is welded to the support columns 22b and 23b, respectively.

[0038] A rear plate 25 with a bent portion is erected on the upper surface of the bottom plate 21 at the rear of the frame 20, and the contact portion with the bottom plate 21 is joined by welding.

[0039] The rear plate 26, which serves as the second support member, is joined to the rear plate 25 by welding in a manner that extends upward. The rear plate 26 has a flat portion 26b formed by bending it at approximately a right angle to the vertical portion 26a. In this embodiment, the flat portion 26b is a horizontal plane. In this embodiment, "approximately a right angle" includes an error of ±1° from a right angle (the same applies to the other embodiments described below). Therefore, the flat portion 26b is bent at a range of 89° to 91° relative to the vertical portion 26a (the same applies to the other flat portions described below).

[0040] Furthermore, in this embodiment, the planar portion 26b is formed in two parts due to the configuration of the device, but it may also be formed as a single unit. In addition, the rear plate 26 includes a vertical surface portion 26c formed by bending from the vertical surface portion 26a.

[0041] The beam members 27a and 27b mainly have an L-shaped cross-section and are fixed to the support columns 22b and 23b and the rear side plate 26, respectively.

[0042] The beam members 27c, 27d, and 27e mainly have a U-shaped cross-section and are fixed to the support columns 22b, 23b and the rear side plate 26, respectively.

[0043] The beam member 27f is fixed to the support column 22b and to the support column 23b, respectively, maintaining rigidity as a frame.

[0044] Figure 3 is a perspective view of the frame 20, viewed from the rear, showing the frame 20 with stays and intermediate members for mounting the optical scanning devices 1a, 1b, 1c, and 1d, respectively. Figure 4 is a perspective view of the frame 20, viewed from the front, showing the frame 20 with stays and intermediate members for mounting 1b, 1c, and 1d, respectively. Note that in Figures 3 and 4, the beam member 27b shown in Figure 2 is not shown in order to make the stays and intermediate members easier to see.

[0045] In Figures 3 and 4, the stays 31a, 31b, 31c, and 31d, which serve as mounting members on which the optical scanning devices 1a, 1b, 1c, and 1d are respectively mounted, are made of steel plates, and each supports the optical scanning devices 1a, 1b, 1c, and 1d shown in Figure 1.

[0046] The stay 31a has a vertical surface portion 31a(b) that is substantially perpendicular to the plane 31a(a) on which the optical scanning device 1a is mounted. The opposite side similarly has a vertical surface portion 31a(c) that is substantially perpendicular to the plane 31a(a).

[0047] The intermediate member 32, as a connecting member, is made of steel plate and comprises the aforementioned planar portion 32b, which is a plane extending in a direction perpendicular to the vertical direction, and a vertical surface portion 32a, which is a plane extending in the vertical direction and formed by bending approximately perpendicular to the planar portion 32b. In this embodiment, the intermediate member 32 has an integrated shape at the attachment points of all the stays 31a, 31b, 31c, and 31d in order to prioritize ease of assembly, but this may be provided for each stay.

[0048] The vertical surface portion 31a(b) of the stay 31a is fastened and fixed to the front side plate 24.

[0049] The vertical surface portion 31a(c) of the stay 31a is fastened and fixed to the vertical surface portion 32a of the intermediate member 32.

[0050] The flat portion 32b of the intermediate member 32 is fastened and fixed to the flat portion 26b of the rear plate 26.

[0051] Figure 5 is an exploded perspective view of the frame 20 showing the fastening and fixing configuration.

[0052] In Figure 5, the front plate 24 has an elongated hole 24a that extends vertically. When the stay 31a is adjusted vertically using a tool described later so that the distance between the rotation center of the photoreceptor drum 2a in Figure 1 and the optical scanning device 1a on which it is mounted is the desired distance, the screw 41 passes through the elongated hole 24a and screws into the hole 31a(d) in the vertical surface portion 31a(b) of the stay 31a, thereby fastening and fixing the vertical surface portion 31a(b) of the stay 31a to the front plate 24.

[0053] The vertical surface portion 32a of the intermediate member 32 has an elongated hole 32c that extends vertically and serves as a vertical surface adjustment means. When the stay 31a is adjusted vertically using a tool described later so that the distance between the rotation center of the photoreceptor drum 2a in Figure 1 and the optical scanning device 1a on which it is mounted is a desired distance, the screw 42 passes through the elongated hole 32c and screws into the hole 31a(e) in the vertical surface portion 31a(c) of the stay 31a, thereby fastening and fixing the vertical surface portion 31a(c) of the stay 31a to the vertical surface portion 32a of the intermediate member 32.

[0054] Furthermore, the flat portion 32b of the intermediate member 32 has an elongated hole 32d that extends in the front-rear direction as a means for adjusting the flat portion. When fastening the vertical surface portion 32a of the intermediate member 32 to the vertical surface portion 31a(c) of the stay 31, the screw 43 passes through the elongated hole 32d at the position where the intermediate member 32 has slid, so as not to deform the stay 31, and screws into the hole 26d in the flat portion 26b of the rear plate 26 in which the screw is formed, thereby fastening and fixing the flat portion 32b of the intermediate member 32 to the flat portion 26b of the rear plate 26.

[0055] In addition, stays 31b, 31c, and 31d are similarly fastened and fixed to the front plate 24 and the intermediate member 32, so corresponding reference numerals are used for the corresponding components and their explanations are omitted.

[0056] Next, the assembly procedure for the stay 31a and the intermediate member 32 will be explained using Figure 6.

[0057] Figure 6 is an explanatory diagram illustrating the assembly procedure of the stay 31a and the intermediate member 32.

[0058] In Figure 6, the first step is to set a tool (not shown) into the frame, which accurately sets the distance between the rotation center of the photoreceptor drum 2a in Figure 1 and the plane 31a(a) of the stay 31a.

[0059] As the second step, the stay 31a is placed on the tool, as shown in Figure 6(A). In Figure 6, this mounting surface is schematically represented by a triangle (upward-pointing triangle) 40.

[0060] As a third step, as shown in Figure 6(B), the flat portion 32b of the intermediate member 32 is set on the flat portion 26b of the rear plate 26, and a force is applied in the direction of arrow A such that the flat portion 32b of the intermediate member 32 can slide on the flat portion 26b of the rear plate 26.

[0061] As the fourth step, as shown in Figure 6(C), the vertical surface portion 31a(b) of the stay 31a is fastened and secured to the front side plate 24 with screws 41 so as to be pulled in.

[0062] As the fifth step, as shown in Figure 6(D), the vertical surface portion 32a of the intermediate member 32 is fastened and secured with screws 42 so as to be pulled into the vertical surface portion 31a(c) of the stay 31a.

[0063] As the sixth step, as shown in Figure 6(E), the intermediate member 32 is fastened and fixed to the vertical surface portion 32a of the intermediate member 32 with screws 43 at the position where the intermediate member 32 has slid so as not to deform the stay 31a in the fifth step of fastening and fixing the stay 31a to the vertical surface portion 32a of the intermediate member 32 with screws 43.

[0064] By following the above procedure, it becomes possible to accurately set the distance between the photoreceptor drum 2a and the optical scanning device 1a while suppressing deformation of the stay 31a.

[0065] Although Figure 6 describes stay 31a, stays 31b, 31c, and 31d can be assembled using the same procedure.

[0066] Furthermore, in this embodiment, the intermediate member 32 is configured to be fastened and secured to the rear plate 26 with screws, but the same effect can be obtained by forming a flat surface on the front plate 24 and reversing the fastening configuration with the intermediate member 32.

[0067] Next, a second embodiment of the present invention will be described using Figure 7 to illustrate the configuration and assembly procedure of the stay and intermediate member. The other configurations of this embodiment are the same as those shown in the first embodiment above, and the same reference numerals are used for members having the same configuration and function, and the description of the first embodiment will be referenced, with detailed explanations omitted.

[0068] Figure 7 is an explanatory diagram illustrating the configuration and assembly procedure of the stay and intermediate member.

[0069] In Figure 7, the stay 33a, which corresponds to the stay 31a in Figures 3 and 4, is made of steel plate and supports the optical scanning device 1a.

[0070] The stay 33a has a vertical surface portion 33a(b) that is substantially perpendicular to the plane 33a(a) on which the optical scanning device 1a is mounted, and the opposite side has a flat surface portion 33a(c) that extends from the plane 33a(a).

[0071] The vertical surface portion 33a(b) of the stay 33a is provided with a screw-filled hole, similar to the first embodiment. Using the tool described below, the stay 33a is adjusted vertically so that the distance between the rotation center of the photoreceptor drum 2a in Figure 1 and the optical scanning device 1a on which it is mounted is a desired distance. At this position, the screw 46 passes through the elongated hole in the front plate 24 and screws into the hole in the vertical surface portion 33a(b) of the stay 33a, thereby fastening and fixing the vertical surface portion 33a(b) of the stay 33a to the front plate 24.

[0072] The intermediate member 34, which corresponds to the intermediate member 32 in Figure 4, is made of steel plate and comprises a vertical surface portion 34a that is a plane extending in the vertical direction and a flat surface portion 34b that is formed by bending approximately perpendicular to the vertical surface portion 34a.

[0073] The vertical surface portion 26c of the rear plate 26 has an elongated hole that extends vertically and serves as a vertical adjustment means. When the stay 33a is adjusted vertically using the tool described below so that the distance between the rotation center of the photoreceptor drum 2a in Figure 1 and the optical scanning device 1a on which it is mounted is the desired distance, the screw 47 passes through the elongated hole formed in the vertical surface portion 26c of the rear plate 26 and screws into the hole in the vertical surface portion 34a of the intermediate member 34, which has a screw thread, thereby fastening and fixing the vertical surface portion 34a of the intermediate member 34 to the vertical surface portion 26c of the rear plate 26.

[0074] The flat portion 33a(c) of the stay 33a has an elongated hole that extends in the front-rear direction and serves as a flat portion adjustment means. When fastening the vertical surface portion 34a of the intermediate member 34 to the vertical surface portion 26c of the rear plate 26, the screw 48 passes through the elongated hole formed in the flat portion 33a(c) of the stay 33a at a position where the intermediate member 34 has slid, so as not to deform the stay 33, it screws into the hole in the flat portion 34b of the intermediate member 34 where the screw is formed, thereby fastening and fixing the flat portion 34b of the intermediate member 34 to the flat portion 33a(c) of the stay 33a.

[0075] Next, the assembly procedure for the stay 33a and the intermediate member 34 will be explained.

[0076] As the first step, a tool (not shown) is set into the frame, which precisely sets the distance between the rotation center of the photoreceptor drum 2a and the plane 33a(a) of the stay 33a.

[0077] In the second step, as shown in Figure 7(A), the intermediate member 34 and the stay 33a are placed on the tool, and a force is applied in the direction of arrow B such that the flat portion 33a(c) of the stay 33a can slide on the flat portion 34b of the intermediate member.

[0078] As a third step, as shown in Figure 7(B), the vertical surface portion 33a(b) of the stay 33a is fastened and secured to the front plate 24 with screws 46 so as to be pulled in.

[0079] As the fourth step, as shown in Figure 7(C), the vertical surface portion 34a of the intermediate member 34 is fastened and secured with screws 47 so as to be pulled into the vertical surface portion 26c of the rear plate 26.

[0080] As the fifth step, as shown in Figure 7(D), in the fourth step of fastening and fixing the vertical surface portion 34a of the intermediate member 34 to the vertical surface portion 26c of the rear plate 26, the flat portion 34b of the intermediate member 34 and the flat portion 33a(c) of the stay 33a are fastened and fixed with screws 48 in the position where the intermediate member 34 has slid to prevent deformation of the stay 33a.

[0081] Here, screws 46, 47, and 48 are arranged in multiple locations in the direction of the paper.

[0082] By following the above procedure, it becomes possible to accurately set the distance between the photoreceptor drum and the optical scanning device while suppressing deformation of the stay 33a.

[0083] Although Figure 7 describes stay 33a, the stays corresponding to stays 31b, 31c, and 31d in Figures 3 and 4 can be assembled using the same procedure.

[0084] Furthermore, in this embodiment, the intermediate member 34 is configured to be fastened and fixed to the rear plate 26 with screws, but the same effect can be obtained by fastening and fixing the intermediate member 34 to the front plate 24.

[0085] Next, a third embodiment of the present invention will be described using Figure 8 to illustrate the configuration and assembly procedure of the stay and intermediate member. The other configurations of this embodiment are the same as those shown in the first embodiment above, and the same reference numerals are used for members having the same configuration and function, and the description of the first embodiment will be referenced, with detailed explanations omitted.

[0086] Figure 8 is an explanatory diagram illustrating the configuration and assembly procedure of the stay and intermediate member.

[0087] In Figure 8, the first step is to set a tool (not shown) into the frame, which accurately sets the distance between the rotation center of the photoreceptor drum 2a and the plane 31a(a) of the stay 31a.

[0088] As the second step, the stay 31a is placed on the tool, as shown in Figure 8(A).

[0089] As a third step, as shown in Figure 8(B), the flat portion 32b of the intermediate member 32 is set on the flat portion 26b of the rear plate 26, and a force is applied in the direction of arrow A so that the flat portion 32b of the intermediate member 32 can slide on the flat portion 26b of the rear plate 26, and the gap is further biased to 0.3 mm or less.

[0090] As the fourth step, as shown in Figure 8(C), the stay 31a is clamped so that the gap between the vertical surface portion 31a(b) and the front plate 24 is 0.3 mm or less.

[0091] Here, the clamp is schematically represented by opposing arrows.

[0092] As the fifth step, as shown in Figure 8(D), the intermediate member 32 is clamped so that the gap between the vertical surface portion 32a of the intermediate member 32 and the vertical surface portion 31a(c) of the stay 31a is 0.3 mm or less.

[0093] In the sixth step, the area near the biased point indicated by arrow A and the area near the clamping point are fastened and secured by welding, integrating the intermediate member and stay with the frame.

[0094] By following the above procedure, it becomes possible to accurately set the distance between the photoreceptor drum 2a and the optical scanning device 1a while suppressing deformation of the stay.

[0095] Although Figure 8 describes stay 31a, stays 31b, 31c, and 31d can be assembled using the same procedure.

[0096] Furthermore, although in this embodiment the intermediate member 32 is welded to the rear plate 26, the same effect can be obtained by forming a flat portion on the front plate 24 and reversing the fastening and fixing configuration with respect to the intermediate member 32, thereby welding the intermediate member 32 to the flat portion on the front plate 24.

[0097] Furthermore, by fastening the vertical surfaces together by welding, it becomes possible to eliminate concerns about displacement that might occur if the fastening were done with screws, due to vertical impacts that occur during equipment transportation, etc.

[0098] Next, the configuration and assembly procedure of the stay and intermediate member will be described using Figure 9 as an example of a fourth embodiment of the present invention. The other configurations of this embodiment are the same as those shown in the second embodiment, and the same reference numerals are used for members that have the same configuration and function, and the description of the second embodiment will be referenced, with further detailed explanations omitted.

[0099] Figure 9 is an explanatory diagram illustrating the configuration and assembly procedure of the stay and intermediate member.

[0100] In Figure 9, the first step is to set a tool (not shown) into the frame, which accurately sets the distance between the rotation center of the photoreceptor drum 2a and the plane 33a(a) of the stay 33a.

[0101] In the second step, as shown in Figure 9(A), the intermediate member 34 and the stay 33a are placed on the tool, and a force is applied in the direction of arrow B such that the flat portion 33a(c) of the stay 33a can slide on the flat portion 34b of the intermediate member, and the gap is further biased to 0.3 mm or less.

[0102] As a third step, as shown in Figure 9(B), the stay 33a is clamped so that the gap between the vertical surface portion 33a(b) and the front plate 24 is 0.3 mm or less.

[0103] As the fourth step, as shown in Figure 9(C), the intermediate member 34 is clamped so that the gap between the vertical surface portion 34a of the intermediate member 34 and the vertical surface portion 26c of the rear plate is 0.3 mm or less.

[0104] In the fifth step, the area near the biased point indicated by arrow B and the area near the clamping point are fastened and secured by welding, integrating the intermediate member and stay with the frame.

[0105] By following the above procedure, it becomes possible to accurately set the distance between the photoreceptor drum 2a and the optical scanning device 1a while suppressing deformation of the stay 33a.

[0106] Although Figure 9 describes stay 33a, the stays corresponding to stays 31b, 31c, and 31d in Figures 3 and 4 can be assembled using the same procedure.

[0107] Furthermore, although the intermediate member 34 is welded to the rear plate 26 in this embodiment, the same effect can be obtained by welding the intermediate member 34 to the front plate 24.

[0108] Next, the configuration and assembly procedure of the intermediate member and stay will be described using Figure 10, as is the fifth embodiment of the present invention. The other configurations of this embodiment are the same as those shown in the first embodiment, and the same reference numerals are used for members that have the same configuration and function, and the description of the first embodiment will be referenced, with detailed explanations omitted.

[0109] As the intermediate member 32 shown in Figure 6 of the first embodiment has a cantilevered shape, if the vibration of the drive motor or the like during image formation is large, the optical scanning device 1 may vibrate, causing image defects.

[0110] By implementing this embodiment, image defects caused by vibration can be suppressed.

[0111] Figure 10 is an explanatory diagram illustrating the configuration and assembly procedure of the stay and intermediate member.

[0112] In Figure 10, the state shown in Figure 10(A) is the same as the state after progressing to the sixth step shown in Figure 6(E).

[0113] The intermediate member 32 has a vertical surface portion 32e which is an extension of the vertical surface portion 32a in Figure 6.

[0114] The rear plate 26 includes a vertical surface portion 26e formed by bending from the vertical surface portion 26a.

[0115] As the seventh step, as shown in Figure 10(B), the vertical surface portion 32e of the intermediate member 32 is fastened and secured with screws 49 on the opposite side of the screws 43 so as to pull it into the vertical surface portion 26e of the rear plate 26.

[0116] By forming the intermediate member 32 from a steel plate thinner than the stay 31a, deformation of the stay 31a can be suppressed when fastening and fixing the intermediate member 32 to the rear side plate 26, making it possible to accurately set the distance between the photoreceptor drum 2a and the optical scanning device 1a.

[0117] Here, multiple screws 49 are arranged in the direction of the paper.

[0118] Although Figure 10 describes stay 31a, stays 31b, 31c, and 31d can be assembled using the same procedure.

[0119] Furthermore, in this embodiment, the same effect can be obtained even if the fastening and fixing of the intermediate member 32 to the front plate 24 and the rear plate 26 is reversed. [Explanation of Symbols]

[0120] 1a, 1b, 1c, 1d... Optical scanning devices 2a, 2b, 2c, 2d... Photoconductor drum 20...Frame 21…Bottom plate 22a, 22b, 23a, 23b...posts 24…Front side panel 24a…long hole 25…Rear side plate 26…Rear side plate 26b…Plane part 26c…Vertical surface part 26e…Vertical surface part 31a, 31b, 31c, 31d…ステー 31a(a), 31b(a), 31c(a), 31d(a)... plane 31a(b), 31b(b), 31c(b), 31d(b)... Vertical face 31a(c), 31b(c), 31c(c), 31d(c)... Vertical face 32…Intermediate Components 32a…Vertical face 32b… Planar section 32c…long hole 32d…long hole 32e…Vertical face 33a…ステー 33a(a)…plane 33a(b)...Vertical face 33a(c)... Planar part 34…Intermediate Components 34a…Vertical face 34b… Planar section 100…Image forming device

Claims

1. An optical scanning means for forming an electrostatic latent image on a photoreceptor, A mounting member on which the optical scanning means is mounted, The mounting member is fixed to a first support member that supports the mounting member, A second support member, which faces the first support member and supports the aforementioned mounting member together with the first support member, A connecting member comprising a first surface fixed to the second support member and a second surface bent at approximately a right angle to the first surface and fixed to the aforementioned mounting member, the second support member and the aforementioned mounting member, It has, The image forming apparatus is characterized in that the first surface of the connecting member is a plane extending in a direction perpendicular to the vertical direction.

2. The image forming apparatus according to claim 1, further comprising a first surface adjustment means for adjusting the fixing position between the first surface of the connecting member and the second support member.

3. The image forming apparatus according to claim 1 or 2, characterized in that it has a second surface adjustment means for adjusting the fixing position between the second surface of the connecting member and the aforementioned mounting member.

4. The image forming apparatus according to any one of claims 1 to 3, characterized in that the mounting member is made of a steel plate, and the connecting member is made of a steel plate thinner than the mounting member.

5. The image forming apparatus according to any one of claims 1 to 4, characterized in that at least the second surface of the connecting member is fixed by welding.

6. The image forming apparatus according to any one of claims 1 to 5, characterized in that the side of the mounting member that is fixed to the first support member has a surface that is bent at substantially a right angle to the first surface of the connecting member.

7. The image forming apparatus according to any one of claims 1 to 6, characterized in that the second support member is provided at a rearward position of the first support member in the front-rear direction of the image forming apparatus.

Images