Patent attributes
Provided, for example, is a rotary actuator that is equipped with a rotation restricting mechanism for restricting the rotation of a stopped rotor. The rotation restricting mechanism is provided with: a rotation-side restricting member fixed to the rotor; a fixed-side restricting member that engages with the rotation-side restricting member and restricts the movement of the rotation-side restricting member in the circumferential direction of the rotor; and a drive mechanism that moves the fixed-side restricting member in the axial direction of the rotor. A plurality of protrusions that project toward the outer side of the radial direction of the rotor are formed in the rotation-side restricting member. A restricting part 46a that penetrates in between the protrusions in the circumferential direction and restricts the movement of the rotation-side restricting member in the circumferential direction is formed in the fixed-side restricting member.