A refrigerant filling rotary compressor includes a shell, a compressing mechanism, an injection tube and an injection valve assembly. The compressing mechanism includes a cylinder, a main bearing, an auxiliary bearing, a crank shaft, a piston and a sliding vane. An inner wall of the cylinder chamber of the cylinder is formed with a filling mouth, and the cylinder is provided with a filling channel with a filling hole. The injection valve assembly is in a closed state when a pressure inside the cylinder chamber is higher than that in the filling hole so as to separate the filling hole from the filling mouth, and the injection valve assembly is in an open state when the pressure inside the cylinder chamber is lower than that in the filling hole so as to communicate the filling hole with the filling mouth, in which when the injection valve assembly is in the closed state, a space between the injection valve assembly and the filling mouth where a compressed gas exists is termed a clearance volume formed by the injection valve assembly, and a ratio between the clearance volume formed by the injection valve assembly and a reserve volume of the cylinder ranges from 0.3% to 1.5%.

A fixed scroll compressor body includes a scroll compressor body casting. The casting has a central body portion having a plate-like base with a spiral scroll rib projecting from the base at a right angle thereto. The spiral scroll rib includes a volume between the spiraled ribs for the compressing of refrigerant. The spiral scroll rib spirals from a central region of the plate-like base to an outer wall of the central body portion. The casting further includes a first inward-protruding portion that protrudes from the outer wall into the volume. A distance that the first inward-protruding portion protrudes into the volume is greater than a thickness of the first inward-protruding portion such that removal of the first inward-protruding portion results in a first intake opening in the outer wall. The first intake opening provides a path for a flow of refrigerant into the volume.

A rotary pump for delivering fluid includes: a pump housing having a low-pressure inlet and a high-pressure outlet for the fluid to be delivered; and a delivery rotor rotatable about a rotational axis in the pump housing and including a rotor base body and multiple deliverers distributed over the circumference of the rotor base body for delivering fluid from the low-pressure inlet to the high-pressure outlet. When the delivery rotor rotates, the radial and axial outer edges of the deliverers define a delivery region of the pump. The pump includes a flow channeling structure protruding axially into the low-pressure inlet in relation to the rotational axis of the delivery rotor from the pump housing wall in order to influence fluid flowing in the low-pressure inlet. The flow channeling structure arranged axially next to the delivery region and overlaps at least in portions with the delivery region in the radial direction.

A system and method are presented for improved performance of gerotor compressors and expanders. Certain aspects of the disclosure reduce porting losses in a gerotor system. Other aspects of the disclosure provide for reduced deflection in lobes of an outer rotor of a gerotor system. Still other aspects of the disclosure provide for reduced leakage through tight gaps between components of a gerotor system.

A system and method are presented for improved performance of gerotor compressors and expanders. Certain aspects of the disclosure reduce porting losses in a gerotor system. Other aspects of the disclosure provide for reduced deflection in lobes of an outer rotor of a gerotor system. Still other aspects of the disclosure provide for reduced leakage through tight gaps between components of a gerotor system.

A hermetic compressor includes a compression mechanism in a hermetic container. The compression mechanism is driven by an electric motor through a rotation shaft, and includes a cylinder including a cylinder chamber having a cylindrical shape. The cylinder has a cylinder suction hole extending in a radial direction of the cylinder and allowing fluid to be sucked into the cylinder chamber. In an outer circumferential surface of the cylinder, a cylindrical groove is formed in such a manner as to surround the cylinder suction hole. Between the cylinder suction hole and the cylindrical groove, a cylinder tubular portion is provided. To an outer circumferential surface of the cylinder tubular portion, a suction pipe or a connecting pipe provided at one end of the suction pipe is connected, the suction pipe being a pipe through which the fluid is guided from outside of the hermetic container to the cylinder chamber.

In a gear pump, an outer inner wall surface of a suction port which is located on a downstream side in a rotor rotation direction, that is, a first inner wall surface, is located inward of a bottom land between internal teeth of an outer rotor, and the suction port has a shallow portion extended inward from the first inner wall surface on the downstream side in the rotor rotation direction, and a deep portion that is formed so as to be continuous with the shallow portion and that is deeper than the shallow portion. Communication between an inter-tooth chamber and the suction port is cut off with the inter-tooth chamber facing only the shallow portion.

A fixed scroll compressor body includes a scroll compressor body casting. The casting has a central body portion having a plate-like base with a spiral scroll rib projecting from the base at a right angle thereto. The spiral scroll rib includes a volume between the spiraled ribs for the compressing of refrigerant. The spiral scroll rib spirals from a central region of the plate-like base to an outer wall of the central body portion. The casting further includes a first inward-protruding portion that protrudes from the outer wall into the volume. A distance that the first inward-protruding portion protrudes into the volume is greater than a thickness of the first inward-protruding portion such that removal of the first inward-protruding portion results in a first intake opening in the outer wall. The first intake opening provides a path for a flow of refrigerant into the volume.

A parallel connected multiple shaft roots vacuum pump includes an electric motor (30); a pump body which has N (N is an integers and is greater or equal to 2) parallel pump chambers (11); a bladed rotor set (4) installed within the pump body and including an active bladed rotor (3), and 2N1 driven bladed rotors (41, 42, 43); wherein the active bladed rotor includes an active driving gear (8); each driven bladed rotor includes a respective driven gear (401, 402, 403) which are installed at two sides of the active driving gear; a bridge gear set (9) is installed between the active driving gear (8) and two driven gears (402, 403) at a right side of the active driving gear,

A parallel connected multiple shaft roots vacuum pump includes an electric motor (30); a pump body which has N (N is an integers and is greater or equal to 2) parallel pump chambers (11); a bladed rotor set (4) installed within the pump body and including an active bladed rotor (3), and 2N-1 driven bladed rotors (41, 42, 43); wherein the active bladed rotor includes an active driving gear (8); each driven bladed rotor includes a respective driven gear (401, 402, 403) which are installed at two sides of the active driving gear; a bridge gear set (9) is installed between the active driving gear (8) and two driven gears (402, 403) at a right side of the active driving gear.