Developing apparatus

Abstract

The present invention relates to a developing apparatus which has a developer bearing member for bearing developer to develop an electrostatic image formed on an image bearing member with the developer, a developing frame for supporting the developer bearing member, a developer containing frame containing the developer and having a supply opening for supplying the developer to the developing frame and joined to the developing frame, an unsealable sheet member covering the supply opening, and an elastic seal member provided at a drawing opening portion formed between the developing frame and the developer containing frame and through which the sheet member is drawn. The present invention is featured that the seal member can be urged against the sheet member when the sheet member is drawn and sealing the drawing opening portion after the sheet member was drawn, and a deformed amount of the seal member is varied along a drawing direction of the sheet member.

Dependencies are inferred from the claim text.