Engine cooling control device

Claim 1

A cooling system for an internal combustion engine having coolant cavities including: a. a fan; b. a power shaft adapted to be driven by an internal combustion engine; c. fluid clutch means for engaging and disengaging said fan from rotation by said power shaft, said clutch means being actuated by a reciprocating piston carried within an extension of said power shaft; d. a pump, driven by said power shaft, and having within it a closed volume containing a liquid coolant; e. means responsive to a change in pressure in said closed volume of said liquid coolant for actuating said clutch means; f. said means (e) including a bore longitudinally through said power shaft, one end of said bore being in fluid communication with said closed volume of liquid coolant; g. the other end of said bore positioned within a cylinder having one end of said reciprocating piston slidable therein, said other bore end having a bellows around it to thereby define an expansible chamber whose volume is responsive to pressure within said bore, said expansible chamber actuating said piston; h. said cylinder, reciprocating piston, and bellows lying axially outside of said pump; and i. said reciprocating piston provided with a seal therearound, said seal beinG in sealing and sliding engagement with said cylinder.