Patent ID: 7258057

Claim:
A fluid-driven engine, comprising: a drive unit connectable to a source of pressurized fluid and including a piston movable within a cylinder; a valve assembly controlling the introduction of pressurized fluid into said cylinder, and the discharge of spent fluid therefrom for driving said piston with respect to said cylinder; and a rotatable drive shaft including a crank arm coupled to said drive unit for rotating said drive shaft about a rotary axis; said piston projecting through one end of said cylinder and being pivotally coupled to said crank arm for rotating said drive shaft during forward and return strokes of the piston with respect to the cylinder; the opposite end of said cylinder being pivotally mounted to said valve assembly so as to oscillate with said piston between opposite sides of said drive shaft rotary axis during the forward and return strokes of the piston; said opposite end of the cylinder being formed with a port through which pressurized fluid is introduced and spent fluid is discharged as controlled by said valve assembly during the oscillations of said cylinder and piston; said valve assembly including a valve body pivotally mounting said opposite end of the cylinder for pivotal movement about the longitudinal axis of the valve body; said valve body including a rounded surface serving as the pivotal mounting seat for said opposite end of the cylinder and formed with a pair of valve openings spaced from each other so as to be selectively alignable with said port formed in said opposite end of the cylinder during pivotal movements of said cylinder for controlling the introduction of pressurized fluid into the cylinder and the discharge of spent fluid from the cylinder; said valve body further including a cap for at least one of said valve openings, and an elastomeric sleeve between the valve body and the cap for urging the cap against the surface of said cylinder when pivotally mounted to the valve body.