| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device having a spline coupling of a drive transmission device, which is configured to have a gear shape to be mass-produced by injection molding, while improving detachability and rotation transmission performance.SOLUTION: A drive transmission device transmits rotation drive of a motor 20Y of an image forming device body to a photoreceptor drum 1Y detachably mounted on the image forming device body in an axial direction of a shaft 55 thereof. The drive transmission device includes two outer gears 81, 83 with teeth formed on the outer periphery and extended in the axial direction of the shaft 55 of the photoreceptor drum 1Y, and a cylindrical internal gear 82 with teeth formed on the inner periphery of the cylindrical shape so as to be engaged with the outer gears. The cylindrical internal gear 82 engages with one of the two outer gears 81, 83 at one end of the inner periphery, and engages with the other at the other end. The two outer gears 81, 83 have the same shape, and a concave or convex mark is formed in a part other than a tooth surface. The outer gears 81, 83 are connected via the internal gear 82 with the marks facing each other. |
