US-12625456-B2 - Image forming apparatus and manufacturing method for frame of image forming apparatus

US12625456B2US 12625456 B2US12625456 B2US 12625456B2US-12625456-B2

Abstract

An image forming apparatus includes an image forming unit configured to form an image on a recording material, a first metal plate and a second metal plate that face each other to sandwich the image forming unit, and a third metal plate that is located between the first metal plate and the second metal plate and is joined to the first metal plate and the second metal plate. The first metal plate and the third metal plate are welded together at a plurality of welding positions, an adhesive is applied to between the first metal plate and the third metal plate in a range sandwiched between two welding positions of the plurality of welding positions in a region where the first metal plate and the third metal plate are in contact with each other, and the first metal plate and the third metal plate are thereby joined together.

Inventors

Yasuhiko Fuse
Yoji Misao

Assignees

CANON KABUSHIKI KAISHA

Dates

Publication Date: 20260512
Application Date: 20240730
Priority Date: 20220603

Claims (6)

1 . An image forming apparatus comprising: a first metal plate; a second metal plate; an image forming unit configured to form an image on a recording material and configured to be between the first metal plate and the second metal plate; and a third metal plate that is located between the first metal plate and the second metal plate and is joined to the first metal plate and the second metal plate, wherein the first metal plate and the third metal plate are welded together at a plurality of welding positions, wherein an adhesive is between the first metal plate and the third metal plate so that the first metal plate and the third metal plate are joined by the adhesive, wherein the adhesive is between two welding positions of the plurality of welding positions.
2 . The image forming apparatus according to claim 1 , wherein a bent portion is formed by bending a portion of the third metal plate to lie along a surface of the first metal plate, and wherein the adhesive is applied to the bent portion of the third metal plate.
3 . The image forming apparatus according to claim 1 , wherein the second metal plate and the third metal plate are welded together at a plurality of welding positions, wherein an adhesive is between the second metal plate and the third metal plate so that the second metal plate and the third metal plate are joined by the adhesive and between two welding positions of the plurality of welding positions.
4 . The image forming apparatus according to claim 1 , wherein the image forming unit includes a cartridge including a photosensitive member, a charging unit configured to electrically charge the photosensitive member, and a developing unit configured to develop an electrostatic latent image formed on the photosensitive member, and the cartridge is detachably attached to an apparatus main body of the image forming apparatus, wherein the first metal plate and the second metal plate are configured to position the cartridge, and wherein the third metal plate supports the cartridge.
5 . The image forming apparatus according to claim 1 , further comprising a power supply substrate configured to generate a voltage to be applied to the image forming unit, and wherein the third metal plate supports the power supply substrate.
6 . An assembling method for a frame of an image forming apparatus, the assembling method comprising: applying an adhesive to respective surfaces of a first metal plate and a second metal plate; performing assembly such that the first metal plate and the second metal plate sandwich a third metal plate and that the first metal plate and the second metal plate are joined to the third metal plate with the adhesive; welding the first metal plate and the third metal plate at least at two positions such that a position at which the first metal plate and the third metal plate are joined together with the adhesive is between the two positions; and welding the second metal plate and the third metal plate at least at two places such that a position at which the second metal plate and the third metal plate are joined together with the adhesive is between the two places.

Description

CROSS REFERENCE OF RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 18/325,764, filed May 30, 2023 which claims the benefit of priority from Japanese Patent Application No. 2022-090633, filed Jun. 3, 2022, which are hereby incorporated by reference herein in their entirety. BACKGROUND Field of the Disclosure The present disclosure relates to a frame of an image forming apparatus. Description of the Related Art An electrophotographic image forming apparatus has an image formation unit that forms an image on a recording material and a frame (also called frame body) that supports a conveyance unit for conveying a sheet. It is widely known that the frame has a structure with a plurality of metal plates fastened and assembled by screws. In such a structure, the low rigidity of the frame may result in image failures, such as distortion and misalignment of colors, in an image formed in the sheet. In order to achieve the rigidity of the frame sufficient for an image forming apparatus, some measures for improving the rigidity of the frame are taken by, for example, increasing in number the screw-fastening places in the metal plates and/or thickening the metal plates. Meanwhile, Japanese Patent Application Laid-Open No. 2003-66670 discusses a technique in which a plurality of metal plates is joined together by an adhesive to assembly a frame of an image forming apparatus, for example. Japanese Patent Application Laid-Open No. 2021-071699 discusses a technique in which a frame of an image forming apparatus is assembled by a combination of two methods, screw fastening and an adhesive. In such a manner, assembling a frame by using an adhesive achieves weight reduction of the frame due to the use of fewer screws. However, joining a plurality of metal plates by an adhesive may have the disadvantage described below. In general, an adhesive strength is not high against force acting in the peeling direction. Thus, in the case of joining a plurality of metal plates by an adhesive, the rigidity of the frame in the peeling direction of the adhesive is to be made up by, for example, a screw fastening method. Japanese Patent Application Laid-Open No. 2021-071699 discusses a configuration in which metal plates are fastened together with screws near the adhesive application positions, thus preventing the adhesive from peeling. According to the configuration discussed in Japanese Patent Application Laid-Open No. 2021-071699, the use of an adhesive reduces the number of screws as compared to the typical technique. However, there has been a demand for further weight reduction of a frame in recent years. SUMMARY Aspects of the present disclosure provide, in a structure with a frame of an image forming apparatus assembled by using an adhesive, achieving weight reduction of the frame while securing the rigidity of the frame in the peeling direction of the adhesive. According to an aspect of the present disclosure, an image forming apparatus includes an image forming unit configured to form an image on a recording material, a first metal plate and a second metal plate that face each other to sandwich the image forming unit, and a third metal plate that is located between the first metal plate and the second metal plate and is joined to the first metal plate and the second metal plate. The first metal plate and the third metal plate are welded together at a plurality of welding positions, an adhesive is applied to between the first metal plate and the third metal plate in a range sandwiched between two welding positions of the plurality of welding positions in a region where the first metal plate and the third metal plate are in contact with each other, and the first metal plate and the third metal plate are thereby joined together. Further features of the present disclosure will become apparent from the following description of embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of an overall configuration of an image forming apparatus. FIG. 2 is a three-dimensional view of a frame of the image forming apparatus. FIG. 3 is a flowchart of an assembly process of the frame of the image forming apparatus. FIGS. 4A and 4B are diagrams illustrating an adhesive application process. FIG. 5 is a diagram illustrating a frame assembly process. FIG. 6 is a three-dimensional view of an arm end part of a welding machine. FIG. 7 is a diagram illustrating a frame welding process. FIG. 8 is a diagram illustrating the posture of the arm end part in welding a front side plate and a main stay. FIG. 9 is a cross-sectional view of the front side plate and the main stay that are being welded together. FIGS. 10A and 10B are diagrams illustrating the reason that the center part of the frame cannot be welded. FIG. 11 is a diagram illustrating the welding positions and adhesive application positions in the front side plate and the main stay/substrate stay.