Patent ID: 8562465

Claim:
A clip-type tensioner mechanism comprising: a housing in which a hole is formed which is open at one end; a piston which can move in and out of said hole; and a spring which urges said piston so as to protrude from said hole; and a ratchet mechanism; said ratchet mechanism comprising: a plurality of rack teeth comprising a plurality of first rack teeth and a plurality of second rack teeth, which are formed on the outer periphery of said piston; a clip member having a circular portion whereof the diameter can be enlarged, which elastically engages with said rack teeth in a diametric direction; and a recess provided in said housing, having a first face which comes into contact with said clip member when said piston advances, allowing said piston to advance, and a second face which comes into contact with said clip member when said piston retracts, thereby holding said clip member between said rack teeth and restricting retraction of said piston; said second face being inclined obliquely to the axis of said piston; and the position on said oblique second face of said recess where said clip member makes contact when said piston has retracted with said clip member in a state of engagement with any of plurality of first rack teeth, is different than the position on said oblique second face of said recess where said clip member makes contact when the abovementioned piston has retracted with said clip member in a state of engagement with any of said plurality of second rack teeth; wherein wear on said second face is reduced.