A screw rotor which is hollow has improved performance against heat, pressure, rust, and the like. A screw rotor includes a screw portion of which an outer periphery has teeth and grooves having a helical shape and extending by a predetermined length in an axial direction. A radial cross section of at least a part of the screw portion includes a cross section of an outer surface portion forming the teeth and the grooves, a cross section of an axial center portion, a cross section of a support portion that connects an axial center side of the outer surface portion and an outer diameter side of the axial center portion, and a cross section of a hollow portion formed by the support portions adjacent to each other in a rotational direction and an axial center side inner surface of a tooth bottom or a tooth tip. In at least the radial cross section of the screw portion, different members are continuously joined as an integral structure in a cross section of at least one of the axial center portion and the support portion and the outer surface portion.

A rotary compressor may include a rotational shaft, a first bearing and a second bearing each supporting the rotational shaft in a radial direction, a cylinder disposed between the first bearing and the second bearing and forming a compression space, a roller disposed in the compression space to form a contact point spaced at a predetermined interval from the cylinder and coupled to the rotational shaft to compress a refrigerant in response to rotation of the roller, and at least one vane slidably inserted into the roller and in contact with an inner circumferential surface of the cylinder and dividing the compression space into a plurality of compression chambers.

The invention comprises a rotary engine apparatus and method of use thereof, where the rotary engine comprises multiple injection ports. Optional injection ports include a first port in an expansion chamber, a second port in the expansion chamber after a first rotation of the rotor, a third port into the expansion chamber after a second rotation of the rotor, a fourth port from a fuel path through a shaft of the rotary engine, and/or a fifth port into a rotor-vane chamber between the rotor and a vane. Optionally, one or more of the injection ports are controlled through mechanical valving and/or through electronic and/or computer control.

A displacement device including an inner rotor and an outer rotor with meshing projections. Points on each rotor trace a hypotrochoidal path relative to the other. The tips of the outer rotor projections may contact the inner rotor at Top Dead Center (TDC) and Bottom Dead Center (BDC) to form higher and lower pressure regions. Various elements may shape other elements to form seals.

A rotary piston and cylinder device comprising a rotor (2), comprising a rotor surface (2a), a stator (4), a rotatable shutter (3), a piston (5) which extends from the rotor surface, the rotor surface and the stator together defining an annular chamber, and the piston arranged to rotate, through the annular chamber, and the rotor surface being orientated at an incline to a plane (P-P) substantially perpendicular to the axis of rotation (A-A) of the rotor and the rotor surface faces generally away from, or outwardly of, the axis of rotation of the rotor.

A rotary piston and cylinder device comprising a rotor (2), comprising a rotor surface (2a), a stator (4), a rotatable shutter (3), a piston (5) which extends from the rotor surface, the rotor surface and the stator together defining an annular chamber, and the piston arranged to rotate, through the annular chamber, and the rotor surface being orientated at an incline to a plane (P-P) substantially perpendicular to the axis of rotation (A-A) of the rotor and the rotor surface faces generally away from, or outwardly of, the axis of rotation of the rotor.

A pump body assembly and a compressor with the pump body assembly. The pump body assembly includes: an oil supply passage for circulating oil; and two back pressure members, at least one of the two back pressure members being provided with a back pressure groove, the back pressure groove including a first groove section and a second groove section, the first groove section and the second groove section are disposed at intervals, the first groove section communicating with the oil supply passage, the second groove section communicating with the oil supply passage, wherein the communication area of the first groove section and the oil supply passage is a, the communication area of the second groove section and the oil supply passage is b, and a<b.

Apparatus and associated methods relate to a modular rotary engine with a rotating valve shaft assembly. The rotating valve shaft assembly controls the timing of operations that alternately load and seal compressed air in a plurality of adjacent combustion chambers and alternately unload the high-temperature, high-pressure combustion gases from the adjacent combustion chambers into one or more expansion modules. The rotating valve shaft assembly includes at least two rotating valve shafts. Each rotating valve shaft includes ports that alternately open to allow a flow of compressed air from the compression module into a combustion chamber; and close to allow the injection of fuel into the combustion chamber and ignition of the compressed air and fuel mixture. The rotation of the drive shaft of the rotary engine is powered by the expansion of expanding combustion gases that turns the expansion rotor.

A rotary machine, for directing a quantity of fluid from an inlet to an outlet, comprises one or more elliptical or near-elliptical rotors having planetary rotation within a housing. The interior cavity of the housing comprises an inverse apex region that is in contact with the rotor during its rotation. In various embodiments the rotor and housing can be symmetric or asymmetric in cross-section. Features are described that can improve the operation of the machine for various end-use applications. Such features include cut-outs that are fluidly connected to the inlet or outlet ports of the machine, mechanisms for reducing variation in output flow rate from the rotary machine, linings for the interior cavity of the housing, pressure relief mechanisms, dynamic apex seals and other sealing mechanisms.

A rotary machine, for directing a quantity of fluid from an inlet to an outlet, comprises one or more elliptical or near-elliptical rotors having planetary rotation within a housing. The interior cavity of the housing comprises an inverse apex region that is in contact with the rotor during its rotation. In various embodiments the rotor and housing can be symmetric or asymmetric in cross-section. Features are described that can improve the operation of the machine for various end-use applications. Such features include cut-outs that are fluidly connected to the inlet or outlet ports of the machine, mechanisms for reducing variation in output flow rate from the rotary machine, linings for the interior cavity of the housing, pressure relief mechanisms, dynamic apex seals and other sealing mechanisms.