Patent ID: 8678965
Filing Date: 2014-03-25
Classification: F16H

Abstract:
1. An automatic tensioner, comprising: a base; a rotary member which is supported rotatably on the base and to which a pulley around which a belt is wound can be attached; a coil spring including one end locked on the base and an other end locked on the rotary member and adapted to bias the rotary member in one direction with respect to the base; an elastic element having an arc shape including one end locked with a projection member on one of the rotary member and the base and an other end which is a free end, the other end extending along an inner circumferential surface of the other one of the rotary member and the base; and a friction members connected so as to be brought into contact with the inner circumferential surface of the other one of the rotary member and the base and so as not to move in a circumferential direction relatively to the elastic element, wherein the coil spring is disposed in such a state that the coil spring is compressed in an axial direction, and the friction members are pressed against the one of the rotary member and the base by a repulsive force attempting to expand in the axial direction, wherein the arc shape of the elastic member is disposed along the circumferential direction of the inner circumferential surface of the other one of the rotary member and the base, and the one end is bent radially inwards at 90 degrees from the inner circumferential surface of the other one of the rotary member and the base, and the friction members are disposed at equal intervals around the elastic member, wherein individual ones of the friction members become gradually thicker as a distance from the one end of the elastic member increases.