Ignition time adjuster for an internal combustion engine

Claim 1

A pneumatic control valve interposed between a pneumatic pressure soure and an actuator for controlling the air flow there between, comprising: a housing including a bore therein and a radially extending partition wall having surfaces disposed within said bore for dividing said bore into two chambers, one of which is in communication with said actuator and the other of which is in communication with said pneumatic pressure source; a communication passage provided in said partition wall for fluid communication between said two chambers; a resilient valve body provided on said partition wall and sealably engagable with one surface of said partition wall for preventing direct air flow from one of said pneumatic pressure source and actuator through said communication passage to the other of said pneumatic pressure source and actuator and for allowing direct air flow from said other of said pneumatic pressure source and said actuator through said communication passage to said one of said pneumatic pressure source and said actuator; said resilient valve body including an axial bore penetrating therethrough and an orifice means, sealably mounted in said axial bore, for retarding air flow through said axial bore from said one of said pneumatic pressure source and actuator through said axial bore to said the other of said pneumatic pressure source and said actuator.