Patent ID: 8445837

Claim:
A vibration actuator comprising: a drive unit that generates a drive force; a vibrating component that vibrates according to the drive force from the drive unit; a rotating body that receives the vibration of the vibrating component to rotate; and a converting section that changes a contact force between the vibrating component and the rotating body according to size of a load acting on the rotating body, wherein the converting section converts displacement between the rotating body and the vibrating component due to an increase in a rotational load of the rotating body into a change in the contact force, the vibrating component includes a vibrating member that is arranged coaxially with the rotating body and that vibrates according to drive from the drive unit, the converting section includes (i) a transmission member that rotates upon receiving the vibration of the vibrating member and transmits the rotational movement to the rotating body and (ii) a biasing member that generates a bias force biasing the transmission member toward the vibrating member, and the converting section converts displacement between the rotating body and the transmission member due to an increase in the rotational load of the rotating body into a change in the bias force of the biasing member.