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 fuel pump includes a cam arrangement surrounding a rotor and disposed within a spacer ring. The cam arrangement is configured to deterministically translate relative to the spacer ring and the rotor during stroking of the pump. An involute gear set provides an interface between the cam arrangement and the spacer ring. In some cases, the involute gear set is configured to provide a linear translation of the cam arrangement along a timing line. In other cases, the involute gear set is configured to provide a linear translation of the cam arrangement at an angle relative to the timing line.

A fuel pump includes a cam arrangement surrounding a rotor and disposed within a spacer ring. The cam arrangement is configured to deterministically translate relative to the spacer ring and the rotor during stroking of the pump. An involute gear set provides an interface between the cam arrangement and the spacer ring. In some cases, the involute gear set is configured to provide a linear translation of the cam arrangement along a timing line. In other cases, the involute gear set is configured to provide a linear translation of the cam arrangement at an angle relative to the timing line.

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.

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.

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.

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.

A multistage compressor system with intercooler can include a sealed housing with first and second compressor stages, where the first compressor stage is for receiving refrigerant from outside of the sealed housing, and the second compressor stage is for receiving refrigerant from within the sealed housing. The compressor system can also include a crank for mechanically driving the first compressor stage and/or the second compressor stage, and a heat exchanger outside of the sealed housing for receiving refrigerant from the first compressor stage and exchanging heat with the refrigerant. The compressor system can further include an oil reservoir contained by the sealed housing, where the oil reservoir includes oil for lubricating the crank, receives the refrigerant from the heat exchanger, and exchanges heat with the refrigerant to cool the oil in the oil reservoir, and where the refrigerant can be supplied to the second compressor stage.

A multistage compressor system with intercooler can include a sealed housing with first and second compressor stages, where the first compressor stage is for receiving refrigerant from outside of the sealed housing, and the second compressor stage is for receiving refrigerant from within the sealed housing. The compressor system can also include a crank for mechanically driving the first compressor stage and/or the second compressor stage, and a heat exchanger outside of the sealed housing for receiving refrigerant from the first compressor stage and exchanging heat with the refrigerant. The compressor system can further include an oil reservoir contained by the sealed housing, where the oil reservoir includes oil for lubricating the crank, receives the refrigerant from the heat exchanger, and exchanges heat with the refrigerant to cool the oil in the oil reservoir, and where the refrigerant can be supplied to the second compressor stage.