Compact reciprocating piston machine

Claim 2

In a reciprocating poston machine, means defining a longitudinally extending cylinder having a side wall and at least one closed end, a longitudinally movable piston disposed in the cylinder and cooperating with the means defining the cylinder to form a chamber of variable volume at the closed end of said cylinder, inlet and discharge valve means providing communication with said chamber, means forming a slidable seal between the piston and the side wall of the cylinder, said piston being formed to include a transversely extending aperture, a yoke member disposed in the aperture and movable transversely of the piston, said yoke member being formed to include a cylindrical bore extending normally of both the direction of movement of the piston and the direction of movement of the yoke member within the piston, a shaft mounted for rotation about a fixed axis parallel to the axis of the yoke bore, said shaft having a cylindrical portion eccentric to the shaft axis and rotatably disposed in said bore, bearing means extending transversely between the yoke member and piston to provide rolling movement of the yoke member in the aperture, said bearing means including a pair of generally planar roller bearing assemblies each comprising a plurality of rollers engaging longitudinally spacedapart bearing surfaces formed on said yoke member and generally planar bearing race members carried by the piston and engaging the rollers opposite the bearing surface of the yoke member, and means for exerting a longitudinal force on the bearing means and positioning the yoke member longitudinally in the aperture.

Claim 3

A machine as in claim 1 wherein the means forming the slidable seal includes a ring of resilient material disposed in an annular groove in the side of the piston, said ring having a generally U-shaped cross section defined in part by a pair of spaced apart annular lip portions engaging respectively the side wall of the cylinder and the bottom wall of the groove, the open portion of said seal ring facing toward the high pressure end of the piston.

Claim 4

A machine as in claim 1 together with roller bearing means between the yoke member and the cylindrical portion of the shaft.

Claim 5

A machine as in claim 1 together with means carried by the yoke member for limiting movement of the rollers transversely of said member.

Claim 6

A machine as in claim 1 wherein the cylinder is closed at both ends to form two chambers of variable volume, separate inlet and discharge valve means being provided for each of said chambers.

Claim 7

In a reciprocating piston machine, a block having a pair of longitudinally extending bores disposed side-by-side, head assemblies closing the ends of said bores, longitudinally movable pistons disposed in said bores to provide chambers of variable volume at the ends of said bores, inlet and discharge valve means carried by the head assemblies to provide communication with the chambers, said pistons being formed to include transversely extending apertures, yoke members disposed in the apertures and movable transversely of the pistons, bearing means between the yoke member and the bodies of the pistons, bearing means between the yoke members and the bodies of the pistons to provide a rolling movement of the yoke members in the apertures, the bearing means for each piston including a pair of generally planar roller bearing assemblies each comprising a plurality of rollers engaging longitudinally spaced-apart bearing surfaces formed on the yoke member disposed in the piston aperture and generally planar bearing race members carried by the piston and engaging the rollers opposite the bearing surface of the yoke member, means carried by the pistons for preloading the bearing means and positioning the yoke members longitudinally in the apertures, said yoke members being formed to include cylindrical bores extending normally of both the direction of piston movement and the direction of yoke movement within the pistons, shafts mounted for rotation about fiXed axes parallel to the axis of the yoke bores, said shafts having cylindrical portions eccentric to the shaft axis and rotatably disposed to the yoke bores, and drive means engaging the shafts for rotating the same.

Claim 8

In a reciprocating piston machine, a block having a pair of longitudinally extending bores disposed side-by-side, head assemblies closing the ends of said bores, longitudinally movable pistons disposed in said bores to provide chambers of variable volume at the ends of said bores, inlet and discharge valve means carried by the head assemblies to provide communication with the chambers, said pistons being formed to include transversely extending apertures, yoke members disposed in the apertures and movable transversely of the pistons, bearing means between the yoke member and the bodies of the pistons, bearing means between the yoke members and the bodies of the pistons to provide a rolling movement of the yoke members in the apertures, the bearing means for each piston including a pair of generally planar roller bearing assemblies each comprising a plurality of rollers engaging longitudinally spaced-apart bearing surfaces formed on the yoke member disposed in the piston aperture and generally planar bearing race members carried by the piston and engaging the rollers opposite the bearing surface of the yoke member, means carried by the pistons for preloading the bearing means and positioning the yoke members longitudinally in the apertures, said yoke members being formed to include cylindrical bores extending normally of both the direction of piston movement and the direction of yoke movement within the pistons, shafts mounted for rotation about fiXed axes parallel to the axis of the yoke bores, said shafts having cylindrical portions eccentric to the shaft axis and rotatably disposed to the yoke bores, and drive means engaging the shafts for rotating the same.

Claim 9

In a reciprocating piston machine, means defining a longitudinally extending cylinder, a piston disposed in the cylinder, said piston having a pair of longitudinally spaced end walls and an aperture intermediate the end walls, a yoke member having a transversely extending bore and a pair of longitudinally spaced bearing surfaces disposed in the aperture, an eccentric member rotatively mounted in the bore in the yoke member, a pair of bearing pads disposed in the aperture between the bearing surfaces of the yoke member and the end walls of the piston, said bearing pads having bearing surfaces facing the bearing surfaces of the yoke member and longitudinally extending threaded portions facing toward the ends of the piston, a plurality of rollers disposed between the bearing surfaces of the yoke member and bearing pads, and threaded members engaging the threaded portions of the bearing pads, said threaded members having semispherical heads received in semispherical sockets formed in the end walls of the piston.

Claim 10

In a reciprocating piston machine, means defining a longitudinally extending cylinder, a piston disposed in the cylinder, said piston having a pair of longitudinally spaced end walls and an aperture intermediate the end walls, a yoke member having a transversely extending bore and a pair of longitudinally spaced bearing surfaces disposed in the aperture, an eccentric member rotatively mounted in the bore in the yoke member, a pair of bearing pads disposed in the aperture between the bearing surfaces of the yoke member and the end walls of the piston, said bearing pads having bearing surfaces facing the bearing surfaces of the yoke member and longitudinally extending threaded portions facing toward the ends of the piston, a plurality of rollers disposed between the bearing surfaces of the yoke member and bearing pads, and threaded members engaging the threaded portions of the bearing pads, said threaded members having semispherical heads received in semispherical sockets formed in the end walls of the piston.

Claim 11

A machine as in claim 7 further including roller bearing means mounting the eccentric member in the bore in the yoke member.