Thermostatically controlled valve assembly

Claim 1

A thermostatically controlled valve assembly suitable for use as an inlet air temperature control device in an internal combustion engine, said engine including duct structure, said valve assembly including a flap member pivotally movable between first and second extreme positions to regulate flow through said duct structure, said flap member being pivotable about a first axis fixed relative to said duct structure, spring means including at least one uncoiled segment coaxial with said first axis pin joining said flap member to said duct structure, a first coiled portion coaxial with said first axis acting between said flap member and said duct structure to bias said flap member toward said first position, a second coiled portion coaxial with a second axis parallel to but spaced from said first axis, said second coiled portion including a lever means pivotable substantially about said second axis, retaining means on said flap member engaging said second coiled portion and maintaining said second coiled portion in a preloaded condition, temperature sensitive means mounted to said duct structure and having an element movable relative to said duct structure in response to changes in temperature, motion transfer means interconnecting said lever means and said movable element for at least a portion of the range of movement of said movable element to move said flap member toward said second position in response to increases in temperature sensed by said temperature sensitive means, said lever means being biased against said flap member by said second coiled portion and fixed relative to said flap member during movement of said flap member about said first axis from the first position to the second position, said lever means being pivotable about said second axis relative to said flap member upon continued movement of said movable element in direction from the first position to the second position when said flap member is in the second position.