Abstract: A color image forming device in which an operator with no special trained experience can easily replace photosensitive bodies one by one without inviting deterioration in print quality due to shear in printing. The color image forming device has photosensitive bodies having rotational shafts parallelized nearly, the photosensitive bodies being driven respectively and rotatably in a box. The color image forming device forms a color image on a transfer paper sheet by transferring sequentially color manifest images developed on the photosensitive bodies on the transfer paper sheets. The color image forming device includes a positioning and fixing implement coupled axially and removably to the front end of the rotational shaft of each of the photosensitive bodies, for positioning and fixing to the box while the end of the rotational shaft is supported rotatably; and a coupling for coupling axially and detachably the rotational shaft on the base side of the photosensitive body with a drive system fixed on the box.

Abstract: To provide a transmission/coupling device simple in structure and capable of carrying out uniform velocity transmission and quick coupling/decoupling of shafts. A shaft 101 of a photo-sensitive drum 23 has a taper section 103 and a first coupling member 105, mounted on the shaft 101, having a projection 107. An output shaft 111 of a drive motor 67 has a second coupling member 113, mounted on the shaft 111, having a cylindrical bore 115 and a projection 119. When the shafts 101 and 111 are coupled to each other, the taper section 103 is in line-contact with the cylindrical bore 115 to define an engagement circle, and the projections 107 and 119 are engaged with each other to define a power transmission point P which exists in a bisector plane A including the engagement circle, whereby uniform velocity transmission is realized.

Abstract: A plurality of electrostatic recording units are arranged in series along a path for moving a recording sheet of paper, and charged toner images having different colors are formed on the sheet of paper travelled through the path. A paper feeder unit is arranged beneath a paper introduction side of the paper moving path. The sheet of paper carrying the toner image formed thereon is ejected from a paper ejection side of the paper moving path, and is sent to a fixer in which the toner image is fixed on the sheet of paper. The sheet of paper carrying the toner image fixed thereon is sent to a paper receiver tray positioned above the fixer.