Patent ID: 7563086

Claim:
An oscillating piston machine, comprising a housing having an inside of spherical construction, four pistons arranged in said housing, said four pistons being arranged to rotate together in said housing about an axis of rotation which is essentially central in said housing and is fixed with respect to said housing, and to execute reciprocating oscillating movements about a common oscillation axis running essentially through a center of said housing as said pistons rotate in said housing, wherein in each case two adjacent pistons of said four pistons execute oscillating movements in opposite directions, wherein each piston has a working side and a rear side turned away from said working side, a respective working chamber being formed in each case between two of said working sides, which respectively face one another, of two adjacent of said four pistons and said housing, while in each case a secondary chamber which increases or decreases in volume in inverse proportion to said two working chambers is formed between two respective of said rear sides of two adjacent of said four pistons and said housing, and wherein said two secondary chambers together communicate alternatively with one of said two working chambers via at least one inlet valve which permits fluid after compression in said two secondary chambers to pass from both secondary chambers into one of said two working chambers.