Dual action control mechanism

Claim 1

In a dual action control mechanism for supplying fluid under pressure to a first and a second fluid actuatable device having: a. a valve body having an inner end and an outer end; b. a valve chamber located within said valve body; c. an opening in said valve body for communicating a source of fluid under pressure with said valve chamber; d. an exhaust chamber communicating with the atmosphere located at the outer end of said valve body; e. a connecting passageway communicating the valve chamber with the exhaust chamber; f. a reciprocal valve rod located within said valve chamber, which said valve rod is reciprocally movable from a first position adjacent the inner end of said valve chamber to a second position removed from said inner end, a valve stem extending outwardly from said valve rod and into said connecting passageway, said valve stem having a passageway therein communicating said valve chamber with said connecting passageway in the first position of said valve rod; g. a thermal sensor located at the inner end of said valve body, said thermal sensor having a push pin extending into the valve chamber and into contact with the inner end of said valve rod, said valve rod being in its first position when said push pin is unextended and in its second position when said push pin is fully extended; h. a housing member located at the outer end of said valve body, said housing member having a bore communicating with said exhaust chamber, a reciprocal needle valve located and movable within said bore, said needle valve having a conical head portion at its inner end which extends through said exhaust chamber into sealing relationship with the outer terminus of said connecting passageway at the first position of said valve rod and into sealing relationship with the passageway of that portion of the valve stem extending into said connecting passageway at said second position of said valve rod, the bore of said housing member communicating with the atmosphere through a peripherally located exhaust port; i. a first fluid passageway for communicating the valve chamber with a first fluid actuatable device; and j. a second fluid passageway for communicating the connecting passageway with a second fluid actuatable device; the improvement comprising: an exhaust port communicating said valve chamber with the atmosphere; and means for sealing communicating between said valve chamber and said first fluid passageway while said valve rod is in said first position, and means for sealing communication between said valve chamber and said exhaust port while said valve rod is in said second position.