| 摘要 |
PROBLEM TO BE SOLVED: To suitably use a contact member having rubber-like property and to restrain generation of abnormal sound caused by vibration of the contact member when a developer carrier is rotated. SOLUTION: This developing device includes the developer carrier having recessed parts regularly arranged on the surface thereof and being rotatable with a developer thereon; and a contact member, which is made of elastic rubber body, abutted on the surface of the developer carrier, and vibrated with the rotation of the developer carrier, wherein a value obtained by dividing a movement speed of the surface at the time of rotation of the developer carrier by a pitch of the recessed parts in a peripheral direction of the developer carrier is equal to the number of vibrations in which the storage elastic modulus gets smaller than the loss elastic modulus out of the number of vibrations smaller than the number of vibrations of the contact member when a loss tangent obtained by dividing a loss elastic modulus of the contact member by a storage elastic modulus is the greatest. COPYRIGHT: (C)2009,JPO&INPIT |
