An electric vacuum pump applied to a vacuum boosting brake system is provided. The pump has a water containing capacity that is greater than a backflow water capacity of an internal space defined in a pump housing which forms vacuum pressure. The pump includes a watertight chamber that is coupled to an exhaust port of a pump housing.

A control system comprising: a suction line; an exhaust line; an operating liquid line; a liquid ring pump comprising a suction input coupled to the suction line, an exhaust output coupled to the exhaust line, and a liquid input coupled to the operating liquid line; one or more regulating devices configured to control flow of the operating liquid into the liquid ring pump; a first sensor configured to measure a first parameter of an exhaust fluid of the liquid ring pump; a second sensor configured to measure a second parameter of an operating liquid received by the liquid ring pump; and a controller operatively coupled to the sensors and the regulating device(s), and configured to control the regulating device(s) based on measurements by the sensors.

A gerotor pump assembly, and a system and method for operating a gerotor pump assembly, result in a lubrication strategy for operating in a loss-of-prime mode. An inner drive gear may be rotated in a first direction and in a second opposite direction about an axis of rotation. The inner drive gear has a number of projections extending outwardly therefrom. An outer driven gear surrounds the inner drive gear and defines a number of recessions along an inner surface configured to engage with the projections of the inner drive gear. The outer driven gear and the inner drive gear further define at least one dynamically-changing fluid cavity therebetween. The inner drive gear and the outer driven gear define an oil transfer volume clearance between a projection and a recession in a fully engaged position. Oil is maintained within the oil transfer volume clearance as the inner drive gear is rotated.

A control system comprising: a suction line; an exhaust line; an operating liquid line; a liquid ring pump comprising a suction input coupled to the suction line, an exhaust output coupled to the exhaust line, and a liquid input coupled to the operating liquid line; a motor configured to drive the liquid ring pump; a first sensor configured to measure a first parameter of an exhaust fluid of the liquid ring pump; a second sensor configured to measure a second parameter of a gas being received by the liquid ring pump via the suction line; and a controller operatively coupled to the first sensor, the second sensor, and the motor, and configured to control the motor based on sensor measurements of the first sensor and the second sensor.

In the method according to the invention for operating an oil level regulator on a compressor, the oil level regulator monitors an oil level in the compressor and causes oil to be refilled when an oil deficiency is recognized. The oil level regulator provides operating recognition of the compressor in which a check is made as to whether the compressor is in a switched-on or switched-off state, the refilling with oil being carried out only when the compressor is in the switched-on state.

An electric vacuum pump applied to a vacuum boosting brake system is provided. The pump has a water containing capacity that is greater than a backflow water capacity of an internal space defined in a pump housing which forms vacuum pressure. The pump includes a watertight chamber that is coupled to an exhaust port of a pump housing.

A system may include a first compressor, a second compressor, a first heat exchanger and a second heat exchanger. The first compressor has a first inlet and a first outlet. The second compressor is a sumpless compressor and has a second inlet and a second outlet. The second compressor provides working fluid discharged from the second outlet to the first compressor. The first heat exchanger is disposed upstream of the second compressor and provides working fluid to the second compressor. The second heat exchanger is disposed upstream of the first compressor and provides working fluid to the first compressor.

Systems and methods for providing lubricant from a first compressor to a second compressor are provided. A control module receives a start command for a climate-control system having the first and second compressors, allows lubricant from the first compressor to flow into an inlet of the second compressor, turns the second compressor to an ON-mode, and prevents lubricant from the first compressor from flowing into the inlet of the second compressor after the second compressor has been in the ON-mode for a predetermined time period.

A system may include a first compressor, a second compressor, a first heat exchanger and a second heat exchanger. The first compressor has a first inlet and a first outlet. The second compressor is a sumpless compressor and has a second inlet and a second outlet. The second compressor provides working fluid discharged from the second outlet to the first compressor. The first heat exchanger is disposed upstream of the second compressor and provides working fluid to the second compressor. The second heat exchanger is disposed upstream of the first compressor and provides working fluid to the first compressor.

An oil balancing system for a multiple compressor system is provided. The oil balancing system includes an oil equalization line disposed between a first compressor and a second compressor. A first solenoid valve is provided in the oil equalization line. A first signal corresponds to a first oil level in the first compressor. A second signal corresponds to a second oil level in the second compressor. An oil balancing module uses the first signal and the second signal to diagnose an oil imbalance between the first compressor and the second compressor, and applies corrective action, whereby the corrective action includes sending control signals to operate at least one of the first compressor, the second compressor, or the first solenoid valve in a way that eliminates the oil imbalance.