A compressor unit (10) of a refrigerating machine (100) for domestic or commercial use has a rotary compressor (11) which has a BLDC or BLAC motor (13), connected to a compression element (12) for actuating it, and a control device (16) connected to the motor (13), for driving it at a variable speed. The compressor (11) further has a a housing (17) which encloses the motor (13) and the compression element (16) and which has a side wall (20) inside of which the stator (14) of the motor (13) is fixed. The compressor unit (10) also comprises an operating shell (21) covering the housing (17) and in thermal communication with the side wall (20). The operating shell (21) dissipates heat transmitted to it by the housing (17) and contrasts or absorbs or dissipate sound waves having a frequency of between 4 kHz and 16 kHz.

A hermetic compressor includes a compressor shell, a terminal provided on the compressor shell, a terminal guard erected on the compressor shell and surrounding the terminal, and a terminal cover mounted to the terminal guard and covering the terminal. A terminal chamber is defined by the compressor shell, the terminal guard, and the terminal cover. Except for at least a body of the terminal, metal portions facing the terminal chamber are generally covered with an insulator such that the metal portions are not exposed to the terminal chamber. The insulator includes an insulating portion that covers an inner surface of the terminal guard.

An electric screw coolant pump for integration into a temperature control circuit of an assembly of which the temperature is to be controlled. An accommodation housing includes a feeder line and a return line of the temperature control circuit, which open into a cavity. A part of the cavity surrounds a spindle housing and communicates with an outlet opening of the spindle housing as well as the feeder line. A sealing element, which provides a seal between a suction side and a pressure side, is arranged towards an end surface of the axial end of the inserted spindle housing.

In a scroll compressor, at an end plate surface of a fixed scroll, an annular back pressure groove connected to a back pressure chamber is provided, and an arc-shaped first groove and an arc-shaped second groove are provided inside the back pressure groove in a radial direction. A distance between the second groove and the back pressure groove is shorter than a distance between the first groove and the back pressure groove. A revolving scroll is provided with a first hole and a second hole for guiding lubricant oil from an oil supply path to the end plate surface side of the fixed scroll. At least part of a movement locus of an opening of the first hole is included in the first groove. At least part of a movement locus of an opening of the second hole is included in the second groove. The first groove and the second groove at least partially overlap with each other in the radial direction.

A liquid pump device sucking and discharging liquid includes: a pump unit 50, rotating to make the liquid flow; a housing H, accommodating the pump unit and defining a passage 14 of the liquid; and a temperature sensor 80 having a tip region 80a protruded in the passage 14 of the liquid to measure a temperature of the liquid flowing on the passage 14.

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 rotor assembly and a compressor are provided. The rotor assembly has a crankshaft, a rotor core, a balance weight and an oil baffle shield. The rotor core is provided with a vent hole. The vent hole extends through the rotor core along an axial direction of the rotor core. The balance weight is located at one end of the rotor core approximate to an oil sump of the compressor. The oil baffle shield is arranged to cover the balance weight and is provided with a central opening. The crankshaft extends through the central opening. An accommodating space is defined between the oil baffle shield and the rotor core. The accommodating space is communicated with the vent hole.

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.

An electric compressor includes a housing, a drive shaft, a motor, a movable scroll, and a fixed block. The fixed block is fixed to the housing and disposed between the motor and the movable scroll. The motor includes a stator and a rotor. The rotor has an introduction passage that is formed through the rotor in an axial direction of the drive shaft. The drive shaft includes a balance weight that is disposed between the fixed block and the motor and extends to a position where the balance weight covers at least a part of the introduction passage in a radial direction of the drive shaft in a view in the axial direction. The introduction passage includes a first passage located outward of the balance weight in a circumferential direction of the rotor and the drive shaft, and a second passage facing the balance weight in the axial direction.

A method for controlling the rotational speed (S) of an electric motor driven air compressor (2) that supplies compressed air to a pneumatically operated system (5) of a vehicle (1), characterized by the preliminary steps of: a) determining the efficiency (e) of the air compressor (2) for different values (Si) of the rotational speed (S) of the air compressor (2), the efficiency (e) of the air compressor (2) corresponding to the ratio between the pneumatic power (PI) produced by the air compressor (2) and the power (PO) given to the air compressor (2); b) determining one or several specific values (S2, S4) among said different values (Si), for which the efficiency (e) of the air compressor (2) is higher than a threshold value (emin) and/or comparatively higher than those determined for values (SI, S3) close to said specific value(s) (S2, S4); the preliminary steps a) and b) being preferably implemented only once; and characterized by the further repetitive steps of: c) determining the air consumption rate of the pneumatically operated system (5) receiving compressed air from the air compressor (2); d) determining a minimum rotational speed (Smin) of the air compressor (2) to obtain an air production rate of the air compressor (2) that is equal or substantially equal to said determined air consumption rate; e) determining if the specific value or one of the specific values (S2, S4) is greater than said determined minimum rotational speed (Smin); f) if no specific value is greater than said determined minimum rotational speed (Smin), controlling the rotational speed (S) of the air compressor (2) based on said minimum rotational speed (Smin); g) if only one specific value (S4) is greater than said determined minimum rotational speed (Smin), controlling the rotational speed (S) of the air compressor (2) based on said only one specific value (S4); h) if a plurality of specific values (S2, S4) is greater than said determined minimum rotational speed (Smin), determining the specific value (S2) with the best efficiency among said plurality of specific values (S2, S4) and controlling the rotational speed (S) of the air compressor (2) based on said specific value (S2) with the best efficiency.