Patent ID: 9206888
Filing Date: 2015-12-08
Classification: F16H

Abstract:
1. An auto-tensioner comprising: a stationary member having a first cylindrical portion; a rotatable member which has a second cylindrical portion of which at least a part is disposed to overlap the first cylindrical portion in a radial direction, and is supported rotatably relative to the stationary member; a coil spring which is accommodated on insides of the first cylindrical portion and the second cylindrical portion and has one end locked to the stationary member and the other end locked to the rotatable member; and a drainage mechanism provided at a boundary part of the first cylindrical portion and the second cylindrical portion, wherein the drainage mechanism comprises a water inlet configured by a gap between an outer peripheral surface of the first cylindrical portion and an outer peripheral surface of the second cylindrical portion and being open along a peripheral direction, a water passage which is configured by a gap between a water collecting groove formed along the peripheral direction in the outer peripheral surface of one of the two cylindrical portions and the other cylindrical portion, and communicates with the water inlet, and at least one drainage port formed in a peripheral wall on an outside in the radial direction of the water passage.