Patent ID: 7752943

Claim:
An actuator provide with a reduction gear comprising: a motor; a wave reduction gear coaxially connected to a distal end of the motor; and a position detector for detecting a rotational position of a rotating shaft of the motor; wherein the wave reduction gear comprises an annular rigid internal gear, a flexible external gear coaxially disposed inside the rigid internal gear and provided with a cylindrical trunk portion, and a wave generator coaxially fitted inside the flexible external gear; the rotating shaft is passed through an interior of the coaxial trunk portion and is coaxially connected and fixed to the wave generator; the position detector comprises an angle detecting unit having a sensor magnet mounted on the rotating shaft and a magnetic sensor facing the sensor magnet, and a sensor signal converter for processing detection signals from the magnetic sensor; the angle detecting unit is disposed in a portion positioned inside the cylindrical trunk portion around the rotating shaft, and the sensor signal converter is disposed at a rear end of the motor; the motor is provided with wiring holes whose interiors pass through and extend from an angle detecting side to a sensor signal converter side; and the angle detecting unit and the sensor signal converter are electrically connected by wires through the wiring holes.