| 摘要 |
PROBLEM TO BE SOLVED: To increase a carrying developer quantity by constituting a developing sleeve in such a manner that plural recessed parts arrayed in the rotational direction of the developing sleeve are formed in the outer periphery of a cylindrical tube material and plural projected parts projected outside from the outer periphery are formed in parts adjacent to the recessed parts, respectively. SOLUTION: The developing sleeve 1 is constituted in such a manner that the plural recessed parts 1a arrayed in the rotational direction of the developing sleeve 1 are formed in the outer periphery of the cylindrical tube material 13 and the plural projected parts 1b projected outside from the outer periphery of the tube material 13 are formed in the parts adjacent to the recessed parts 1a, respectively. In such a developing sleeve 1, the projected parts 1b are formed so that the improvement of the depth of grooves is more than that of the grooves of a developing sleeve having the recessed parts merely formed in the outer periphery of the tube material. On the other hand, the thickness of the sleeve 1 is reduced so that the distance from a magnetic force generating means 2 to the surface of the sleeve 1 can be made shorter than that in the case the grooves having the same depth are formed only by the recessed parts. Thus, the carried developer quantity can be increased while the sleeve 1 is made small in diameter. |
