An oilcooled air compressor is provided with: an oilcooled air compressor for compressing sucked-in air and discharging the compressed air; an oil separator for separating the compressed air and lubricating oil, which are discharged from the air compressor body; an oil cooler for cooling, by outside air, lubricating oil discharged from the oil separator; oil supply pipe passage for supplying lubricating oil, which is discharged from the oil cooler, to a bearing of the air compressor body and to an intermediate section in the process of compression by the air compressor; and an after-cooler for cooling, by outside air, air discharged from the oil separator. The oil-cooled air compressor in which the air compressor, the oil separator, the oil cooler, and the after-cooler are connected to supply high-pressure air to the outside of the compressor is provided with a vapor compression type refrigeration cycle.

The lubricant level within a reservoir is difficult to monitor, leading to the reservoir being refilled more often than necessary to ensure that the reservoir always contains lubricant. A lubricant level sensing system is connected to and monitors various aspects of the pump assembly that draws lubricant from the reservoir. The pump assembly displaces a known volume of lubricant with each pump stroke. A lubricant-level estimator calculates an estimated lubricant level remaining in the reservoir based on a stroke-count value as sensed from the pump assembly and on a reference value stored in a memory. The estimated lubricant level provides the lubricant remaining and the rate of usage such that maintenance can be scheduled ahead of time to prevent the reservoir running dry.

A compressor may include a shell containing a motor, a compression mechanism and a lubricant sump. The compressor may also include first and second temperature sensors, and a control module. The first temperature sensor may be at least partially disposed within the lubricant sump and may measure a first temperature of a lubricant at a first position. The second temperature sensor may be at least partially disposed within the lubricant sump and may measure a second temperature of the lubricant at a second position that is vertically higher than the first position. The control module is in communication with the first and second temperature sensors. The control module may determine a first difference between the first temperature and the second temperature. The control module may determine whether a liquid level of the lubricant in the lubricant sump is below a predetermined level based on the first difference.

A compressor includes a compression mechanism configured to compress refrigerant, an electromotive mechanism configured to drive the compression mechanism, a shell accommodating the compression mechanism and the electromotive mechanism, a reservoir provided inside the shell and configured to store mixed liquid including liquid refrigerant and refrigerating machine oil, and an electrode provided inside the reservoir and facing an inner surface of the shell.

Compressor device that comprises a compressor element that is equipped with a compression chamber with at least one coolant inlet, and which furthermore comprises a gas outlet, a gas/coolant separation tank connected to it, and, a cooling circuit with a cooler that extends between the separation tank and the coolant inlet, and which is equipped with control means to adjust the temperature of the coolant flow supplied to the compressor element, whereby the aforementioned control means comprise a first and a second sub-controller, each with a different target parameter, whereby the control means also comprise switching means to place one of the two sub-controllers in an activated state and the other sub-controller in a deactivated state.

A compressor system includes a first compressor and a second compressor. A common equalization line fluidly couples the first compressor and the second compressor and provides a single path for passage of fluids between the first compressor and the second compressor. An obstruction device is disposed in the common equalization line. Responsive to one of the first compressor and the second compressor being deactivated while the other of the first compressor and the second compressor remains active, the obstruction device is in a closed configuration. When in the closed configuration, the obstruction device prevents flow of fluid between the first compressor and the second compressor. Prevention of fluid flow between the first compressor and the second compressor causes at least minimum prescribed fluid levels to be maintained in the first compressor and the second compressor.

A compressor includes a shell, a first temperature sensor, a second temperature sensor, and a control module. The shell includes a motor, a compression mechanism and a lubricant sump. The first temperature sensor is at least partially disposed within the shell and configured to measure a first temperature of a lubricant at a first position. The second temperature sensor is at least partially disposed within the shell and configured to measure a second temperature of the lubricant at a second position that is vertically higher than the first position. The control module is in communication with the first and second temperature sensors and configured to determine a first difference between the first temperature and the second temperature. The control module is configured to determine whether a liquid level of the lubricant in the lubricant sump is below a predetermined level based on the first difference.

Systems and methods are provided and include a compressor for a refrigeration system and a duct assembly that includes a duct frame and a sensor unit. The duct frame provides a path for evaporating refrigerant from a lubricant sump of the compressor. The sensor unit obtains temperature measurements of the refrigerant and a lubricant within the lubricant sump and heats and evaporates the refrigerant located within the duct frame of the duct assembly. A control module receives temperature measurements from the sensor unit, determines a presence of liquid refrigerant within the lubricant sump of the compressor in response to a determination that an actual temperature change does not correspond with an expected temperature change for the lubricant, and in response to a determination that the actual temperature change corresponds with the expected temperature change for the lubricant, operates the compressor.

A fluid flow monitoring and management device that includes a fluid flow body having a magnet and a sensor secured to the fluid flow body. The sensor includes a magnetometer in a signal relationship with the magnet.

Refrigerant compressor installation comprising at least three compressors which are arranged in parallel between an intake conduit and a pressure conduit and which each comprise a lubricant sump unit, wherein the compressors, when in operation, work in such a way that the respective pressures in the respective lubricant sump units of the respective compressors form a pressure cascade according to which the compressors have a successively slightly decreasing pressure in the respective lubricant sump unit in a defined cascade sequence, and wherein the lubricant sump units are connected to each other in a manner corresponding to the cascade sequence by way of a lubricant conduit system for lubricant transport, and wherein each lubricant sump unit comprises a port to which is connected an insert element which on the one hand establishes communication with the lubricant conduit system and on the other hand is configured such that it predetermines, for the respective lubricant sump unit, a lubricant level from which lubricant is transported to the lubricant sump unit that follows next in the cascade sequence.