A vane rotary compressor may include a main bearing and a sub bearing provided with a plurality of back pressure pockets each having a different pressure formed on a surface facing the cylinder, a rotational shaft radially supported by the main bearing and the sub bearing, a roller provided with a back pressure chamber that communicates with the plurality of back pressure pockets and having a plurality of vanes configured to divide a compression space into a plurality of compression chambers. At least one of the main bearing or the sub bearing is provided with an oil supply passage that communicates with a back pressure pocket having a relatively low pressure among the plurality of back pressure pockets. Accordingly, oil may be smoothly supplied to a back pressure pocket having a low pressure.

A vane rotary compressor may include a main bearing and a sub bearing provided with a plurality of back pressure pockets each having a different pressure formed on a surface facing the cylinder, a rotational shaft radially supported by the main bearing and the sub bearing, a roller provided with a back pressure chamber that communicates with the plurality of back pressure pockets and having a plurality of vanes configured to divide a compression space into a plurality of compression chambers. At least one of the main bearing or the sub bearing is provided with an oil supply passage that communicates with a back pressure pocket having a relatively low pressure among the plurality of back pressure pockets. Accordingly, oil may be smoothly supplied to a back pressure pocket having a low pressure.

A pump stage assembly including at least two pump suction stages and at least one pump pressure stage. The pump suction stages and the pump pressure stage are arranged spaced apart from one another in a pump housing PG and have a common drive shaft. The pump suction stages are formed by a first assembly of intermeshing external gearwheels that lie in a first plane, and the pump pressure stage is formed by a second assembly of intermeshing external gearwheels that lie in a second plane. A first delivery volume flow can be drawn in from a first region of a dry sump by a first pump suction stage, and a second delivery volume flow can be drawn in from a second region of the dry sump by a second pump suction stage. The two delivery volume flows intermix in the pump housing before they reach an oil tank.

A crankshaft assembly, a compressor and a refrigeration device are provided. The crankshaft assembly has an eccentric shaft component, a spindle component and a main screw oil pump. The eccentric shaft component has an eccentric cavity, and the spindle component has a first cavity communicated with the eccentric cavity. A first through-hole and a second through-hole in a first spindle are each communicated with the first cavity. An outer surface of the first spindle is provided with a first spiral oil groove connecting the first through-hole and the second through-hole. An outer surface of the main screw oil pump is provided with a second spiral oil groove along its length direction, and a spiral direction of the second spiral oil groove is opposite that of the first spiral oil groove.

One embodiment of a modular pump includes a cover and a housing that may be engaged with one another during operation. A gearset may be positioned within an internal portion of the housing. If the modular pump is configured as a rotary pump, the gear set may be comprised of an inner gear positioned within a portion of a ring gear. The modular pump may include a spacer positioned between the cover and the housing to allow the modular pump to be configured with gear sets of varying axial dimensions.

This pump comprises: a housing; a stator which is disposed in the housing and comprises a coil; and pump gears disposed so as to correspond to the stator, wherein the pump gears comprise an outer gear and an inner gear, which is disposed inside the outer gear, and the outer gear is formed of magnetic material.

The disclosure provides a pump device capable of suppressing hydraulic amplitude and reducing noise or vibration associated with hydraulic amplitude while simplifying the structure. The pump device includes: a housing which defines a suction port, a discharge port, and an accommodation chamber; and a pump unit which is arranged in the accommodation chamber and which defines a pump chamber that expands and contracts to exert a pumping action including a suction stroke and a pressurization and discharge stroke on a fluid. The housing includes an air introduction hole that is opened to introduce air into the pump chamber at a predetermined opening timing immediately before the suction stroke is completed.

One embodiment of a method for operating an internal combustion engine under a pressure less than atmospheric pressure includes the steps of positioning a vacuum pump such that said vacuum pump is in fluid communication with a crankcase of said internal combustion engine, connecting a discharge of said vacuum pump to a separator, wherein a portion of said discharge of said vacuum pump condenses in said separator, connecting a vapor discharge of said separator to a filter, wherein said filter removes a portion of volatile organic compounds from said vapor discharge, and venting said filter to an ambient atmosphere.

The present invention provides a vertical, axial flow oil pump (10). The oil pump includes: a casing (11), the casing having a cylindrical shape as a whole and being able to rotate around its own central axis (O); a suction port (12), located at a lower end of the casing in an axial direction, and configured to suck oil into the oil pump; a discharge port (13), located at an upper end of the casing in the axial direction, and configured to discharge the oil from the oil pump to outside; and an impeller (14), provided in and formed integrally with the casing. The impeller rotates together with the casing when the casing rotates, so that the oil is flowed from the suction port to the discharge port. The present invention also provides a scroll compressor having the oil pump.

A vane pump includes a rotor having slits, vanes received in the slits, a cam ring having an inner circumference cam face with which the vanes are brought into sliding contact, a side member, pump chambers formed by the rotor, the cam ring, and adjacent vanes, and back pressure chambers formed in the slits by the vanes. In the vane pump, the side member is provided with a back pressure opening portion opening at a sliding-contact surface in sliding contact with the rotor, the back pressure opening portion being configured to communicate with the back pressure chambers, and a protruding opening portion protruding along the rotating direction of the rotor from an end portion of the back pressure opening portion on the communication-finishing side. An inner-side inner circumferential surface of the protruding opening portion is connected to an inner-side inner circumferential surface of the back pressure opening portion.