Patent ID: 7822364

Claim:
An image forming apparatus comprising: an apparatus main-body that includes a rotatable driving shaft rotated by a driving force of a driving source; a processing unit that includes a rotatable driven shaft and a rotating member arranged on the driven shaft and that is configured to be detachably installed in the apparatus main-body; a coupling mechanism that couples the driving shaft to the driven shaft, the coupling mechanism including a male connector being fixed on either one of the driving shaft and the driven shaft and a female connector being fixed on either one of the driving shaft and the driven shaft on which the male connector is not fixed; and a positioning mechanism that, when the processing unit is installed in the apparatus main-body, performs positioning of the processing unit with respect to the apparatus main-body, the positioning mechanism including a first positioning member in the apparatus main-body and a second positioning member in the processing unit and the first positioning member engages with the second positioning member when the processing unit is installed in the apparatus main-body thereby performing positioning of the processing unit with respect to the apparatus main-body, wherein an end of the driving shaft facing the processing unit is movable in directions orthogonal to the driving shaft, the female connector has an external wall and an internal wall forming therebetween an open-ended ring-like space, and includes a plurality of grooves that run in a direction of depth of the ring-like space on at least one of the external wall and the internal wall, the male connector includes a plurality of spherical bodies that, upon entering into the ring-like space, slide along the track grooves, and when the processing unit is installed in the apparatus main-body, the male connector is coupled with the female connector by inserting the spherical bodies in the ring-like space.