A variable capacity screw compressor comprises a suction port, at least two screw rotors and a discharge port being configured in relation to a selected rotational speed that operates at least one screw rotor at an optimum peripheral velocity that is independent of a peripheral velocity of the at least one screw rotor at a synchronous motor rotational speed for a rated screw compressor capacity. A motor is configured to drive the at least one screw rotor at a rotational speed at a full-load capacity that is substantially greater than the synchronous motor rotational speed at the rated screw compressor capacity. A variable speed drive receives a command signal from a controller and generates a control signal that drives the motor at the selected rotational speed.

A motor-driven compressor includes an inverter that includes a circuit board and an electrical component, and an inverter cover that defines an inverter accommodating chamber together with an end wall of a motor housing member. The inverter accommodating chamber accommodates a first conductive member and a second conductive member. A first end of the first conductive member and a lead of the electrical component extend through the circuit board from a first surface, which faces the end wall, and are soldered to the circuit board on a second surface on a side opposite to the first surface. A first end of the second conductive member is electrically connected to a power supply connector. Second ends of the first conductive member and the second conductive member are mated to each other so as to be electrically connected to each other when the inverter cover is joined to the motor housing member.

A flange is held by a peripheral wall of an intermediate housing member and a peripheral wall of a motor housing member. In this state, bolts are passed through the intermediate housing member and the flange and are threaded to a peripheral wall of the motor housing member, thereby integrally fixing a shaft support housing member to the intermediate housing member and the motor housing member. Thus, the shaft support housing member sufficiently receives the fastening force of the bolts. Vibration of the shaft support housing member is therefore easily suppressed. The intermediate housing member includes a peripheral wall. Thus, the intermediate housing member has a higher stiffness than in a case in which the intermediate housing member does not have the peripheral wall.

A compressor includes a casing that stores lubricant at a bottom, a compression mechanism disposed in the casing to suck and compress a refrigerant, and an oil return member forming an oil return flow path that extends in a top-to-bottom direction to guide the lubricant discharged from the compression mechanism downward. The oil return flow path includes a uniform-cross-section flow path, and a varying-cross-section flow path continuous with a lower end of the uniform-cross-section flow path. A lower end of the varying-cross-section flow path forms an outlet of the oil return flow path and lies along an inner surface of the casing. A the lower end of the varying-cross-section flow path has a greater width than an upper end of the varying-cross-section flow path, and the lower end of the varying-cross-section flow path has a smaller thickness than the upper end of the varying-cross-section flow path.

A rotary compressor is provided that may include a cylinder having an inner peripheral surface defining a compression space; a roller rotatably provided in the compression space, and including a plurality of vane slots at a predetermined interval along an outer peripheral surface, each providing a back pressure; and a plurality of vanes slidably inserted into the plurality of vane slots to rotate together with the roller, front end surfaces of which come into contact with the inner peripheral surface of the cylinder due to the back pressure to partition the compression space into a plurality of compression chambers. The cylinder may further include a suction flow path for refrigerant that may include a suction port that communicates with the compression space to suction the refrigerant in a lateral direction, and a suction passage disposed in a direction that crosses the suction port to provide communication between the compression space and the suction port.

There is disclosed a scroll compressor according to the present disclosure in which a discharge port is formed at a central portion thereof, and a pair of two compression chambers continuously moving toward the discharge port are formed, and a plurality of bypass portions are formed at each interval along a movement path of each compression chamber in the both compression chambers, and compression gradients of the both compression chambers are formed to be different from each other, wherein when an interval between a bypass portion closest to the discharge port and another bypass portion adjacent to the bypass portion among the bypass portions of each compression chamber is defined as a first interval, respectively, a first interval of a second bypass portion belonging to a compression chamber having a relatively larger compression gradient is formed to be smaller than that of a first bypass portion belonging to the other compression chamber between the both compressor chambers.

A method of manufacturing a two-piece counterweight for a scroll compressor is provided. The method includes molding an outer plate, and molding a base having a first opening configured to receive a scroll compressor drive shaft having a longitudinal axis. The method further includes configuring the base for assembly and attachment to the drive shaft. The method also includes attaching the outer plate to the base such that the outer plate is axially offset from the base. In a particular embodiment of this method, the base and outer plate are molded from powdered metal. In certain embodiments, the base and outer plate include one or more openings aligned to permit attachment by inserting a mechanical fastener through the aligned openings. In alternate embodiments, the base and outer plate are attached via brazing or welding.

A scroll compressor includes a housing; a motor provided in the housing; a rotating shaft rotated by the motor; an orbital scroll orbital moved by the rotating shaft; and a fixed scroll forming a compression chamber together with the orbital scroll, wherein the fixed scroll includes an injection hole guiding an intermediate pressure refrigerant to the compression chamber, wherein the compression chamber is formed in a pair, and wherein the injection hole is formed to communicate with any one of the pair of compression chambers when communicating with the other one of the pair of compression chambers. Thereby, an amount of refrigerant discharged from the compression chamber is increased, and thus the performance and efficiency of the compressor may be improved.

A vane rotary compressor includes a roller rotatably supported in a cylinder and including a plurality of vane slots formed along a circumferential direction with back pressure chambers formed at one end of each of the vane slots. A plurality of vanes are slidably supported in the vane slots protruding toward an inner circumferential surface of the cylinder. A compression space formed by the vanes between the roller and the cylinder includes an inlet port and an outlet port formed at both sides of a contact point between the roller and the cylinder. A vane positioned between the inlet port and the outlet port is configured such that a front gap between a front surface of the vane and the inner circumferential surface of the cylinder is smaller than a rear gap between a rear surface of the vane and an inner surface of the back pressure chamber.

A compressor according to embodiments of the present invention may comprise: a first fluid channel provided to communicate with an oil supply fluid channel so as to allow oil to flow therethrough; a second fluid channel provided to extend from the first fluid channel so as to allow the oil to flow to the outside of a case; a third fluid channel extending from the second fluid channel and provided outside the case; and a main fluid channel extending from the third fluid channel and provided through a fixed scroll or a main frame. Accordingly, the oil is supplied to a compression part by passing along the outside of the case, so that oil can be effectively supplied when a high-pressure operation is performed. Moreover, the present invention may not have a facility such as a pressure reduction pin, so that oil can be effectively supplied when a low-pressure operation is performed.