ELECTROPHOTOGRAPHIC IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To improve the image quality and to miniaturize an image forming device when a means for transmitting driving from a drum driving gear to a process cartridge is constituted of a shaft coupling capable of moving in a thrust direction. SOLUTION: This device is equipped with a caulking shaft 25 coaxially provided with shafts respectively fit in a round hole formed in the center of the drum driving gear 22 and a round hole 18d formed in the center of the shaft coupling 18. The shaft 25 may be a stepped caulking shaft consisting of a large-diameter shaft 25a and a small-diameter shaft 25b. The large-diameter shaft is made cylindrical and the small-diameter shaft is formed to be extended inside the large-diameter shaft side, so that a device main body is constituted to be compact in the thrust direction.