Developing device, process cartridge, electrophotographic image forming apparatus, and developer container and method of assembling the developer container

摘要

A developer container with an increased capacity that does not enlarge a process cartridge or an apparatus main body used therewith includes flanges on an opposite surface of a developing frame respectively contacting flanges formed on the upper part and the lower part on a wall surface of a container frame, on which a developer feeding opening is formed. To form the developer, container the flanges are welded at their connection portions by ultrasonic welding. Then, a flange of a lid frame is connected to a flange of the container frame by ultrasonic waves, thereby forming a developer container, in which the container frame is connected with the developing frame with the developer feeding opening being put between the frames.