Patent ID: 7571632

Claim:
A method of manufacturing a chain tensioner including a tubular housing having a bottom, a plunger installed in an inner periphery of the housing so as to smoothly slide therein, a return spring providing the plunger with a force pushing outward, a resister ring installed between the inner periphery of the housing and an outer periphery of the plunger, and plural latching grooves and a first stopper each capable of mating with the resister ring; and limiting backward movement of the plunger by mating the latching groove with the first stopper via the resister ring, the method comprising: forming the latching grooves on the outer peripheral surface of the plunger, each latching groove having a tapered face on which the register ring slides back and forth along with a reciprocating movement of the plunger, each latching groove that includes the tapered face being formed by rolling.