Drum unit including photosensitive drum, drum frame, and pressure member pressing developing cartridge attached to drum frame toward photosensitive drum

Abstract

A drum unit includes: a photosensitive drum rotatable about a drum axis extending in a first direction; a drum frame to which a developing cartridge including a developing roller is attachable; and a pressure member. The drum frame includes a guide frame positioned at one end portion in the first direction of the drum frame. The guide frame has a guide groove allowing a portion of the developing cartridge to be inserted therein. The pressure member is provided at the guide frame at a position inward relative to the guide groove in the first direction. The pressure member is pivotally movable about a pressure axis extending in the first direction. The pressure member presses the developing cartridge toward the photosensitive drum in a state where the developing cartridge is attached to the drum frame.