Rotary actuator

A rotary actuator comprising:

• a hollow motor provided with a motor housing and a hollow motor shaft that is rotatably supported by the motor housing and extends to pass through in an axial direction;
• a strain wave gearing that is coaxially disposed at a front end of the hollow motor in the axial direction and that reduces rotation outputted by the hollow motor;
• an output member that is coaxially disposed at a front end of the strain wave gearing in the axial direction and that transmits the reduced rotation outputted from the strain wave gearing to a load side;
• an output-side detector that detects a rotation state of the output member;
• a cylindrical sleeve extending in the axial direction through the hollow motor shaft, the strain wave gearing, and the output member;
• and
• an actuator hollow portion that is formed by the sleeve and is open at both ends in the axial direction,
• wherein
• the sleeve is a fixed-side member that has a rear end part fixed to a housing rear end part of the motor housing, the housing rear end part being positioned at a rear end of the motor housing in the axial direction, and
• the output-side detector includes
• a fixed-side detector component that is attached to a front end part of the sleeve passing through the output member, and
• a rotation-side detector component that is attached to the output member so as to face the fixed-side detector component.