Patent ID: 7465248

Claim:
A planetary gear type reduction gear with torque limiter including at least one stage of a planetary gear type reduction mechanism, the planetary gear type reduction gear comprising: a stationary member; an input shaft rotatably supported in the stationary member: an output shaft rotatably supported in the stationary member; a central gear; a planetary gear meshed with the central gear; an inner gear meshed with the planetary gear; and a carrier rotatably supporting the planetary gear, wherein the torque limiter is formed between the input shaft and the output shaft, the torque limiter being comprised by the inner gear, which is opposed to a surface of the stationary member and disposed with a clearance in a radial direction relative to the stationary member, and the inner gear is opposed in the axial direction relative to the stationary member by means of a friction member, and the inner gear is under pressure from the friction member in the axial direction such that the inner gear is retained at a side of the stationary member by the friction member, wherein the friction member is provided at each side of the inner gear, and the inner gear is opposed and disposed to the side of the stationary member by means of the friction member, and both sides of the inner gear are caused to contact the side of the stationary member by means of the friction member, and the inner gear is retained at the side of the stationary member by the friction force between the friction member and the side of the stationary member and by the friction force between the friction member and the inner gear under pressure from the friction member.