Rotary piston apparatus

Rotary piston assembly comprising a housing having a bore, a piston rotatably mounted in the housing, a plurality of slide vanes distributed about the circumference of said piston, each side vane supported for pivotal movement about an axis parallel to the axis of rotation of said piston, said slide vanes operable to pivot and engage the bore of the housing during rotation of the piston due to the effect of centrifugal force, each of said slide vanes being of arcuate, vane shaped configuration having an enlarged end section of generally circular cross section, means defining a plurality of axially directed, circumferentially spaced arcuate recesses on the outer peripheral surface of said rotary piston to receive the end sections of said pivoted slide vanes and means for controlling pivotal movement of said slide vanes comprising an axially movable member having a conical peripheral surface mounted in a bore of the rotary piston shaft and a plurality of elongated pins engaging in radially disposed slots in the piston disposed at an angle to a radial plane through the axis of the conical member and pivot axis of the slide vane, one terminal end of said pins engaging an arcuate recess in an end section of the slide vane and the opposite end engaging the outer peripheral surface of said conical member.