The present invention provides an oil pump device capable of preventing foreign matters from getting caught at a sliding part of an oil pump, and thus of preventing a situation where the oil pump is locked and prevented from rotating. The oil pump device includes an oil pump connected to a supply target apparatus by a hydraulic circuit, the oil pump discharging and supplying oil to the supply target apparatus through the hydraulic circuit; a motor driving the oil pump; a trapping member interposed along the hydraulic circuit, the trapping member trapping a foreign matter mixed in the oil discharged from the oil pump; and a motor control unit controlling the motor to perform a normal control mode of driving the oil pump in a normal control rotation range and perform, at operational start of the oil pump, a lock-avoiding mode of driving the oil pump with a lock-avoiding rotational speed set in advance as a lower limit.

A method for determining a flow volume of a fluid delivered by a pump. The flow volume is determined as a function of predefined pump information depending on a pump geometry, rotation speed information, which correlates with the rotation speed of the pump, and pressure information, which correlates with a differential pressure at the pump.

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.

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 pump configured to pump operating liquid into the liquid ring pump via the operating liquid line and the liquid input; a motor configured to drive the pump; a first sensor configured to measure a first parameter, the first parameter being a parameter of an exhaust fluid of the liquid ring pump; a second sensor configured to measure a second parameter, the second parameter being a parameter of a fluid received by the liquid ring pump; 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. The control system advantageously tends to reduce or eliminate the wear caused by cavitations.

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 pump configured to pump operating liquid into the liquid ring pump via the operating liquid line and the liquid input; a motor configured to drive the pump; a first sensor configured to measure a first parameter, the first parameter being a parameter of an exhaust fluid of the liquid ring pump; a second sensor configured to measure a second parameter, the second parameter being a parameter of a fluid received by the liquid ring pump; 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. The control system advantageously tends to reduce or eliminate the wear caused by cavitations.

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 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.

A method for determining a flow volume of a fluid delivered by a pump, wherein the flow volume is determined as a function of predefined pump information depending on a pump geometry, rotation speed information, which correlates with the rotation speed of the pump, and pressure information, which correlates with a differential pressure at the pump.

Provided is an oil feed type air compressor which can increase the determination accuracy regarding a deterioration state of oil. An oil feed type air compressor 1 includes a compressor main body 3, a separator 6 that separates oil from compressed air discharged from the compressor main body 3, and an oil feeding system 8 that feeds the oil separated by the separator 6 into a compression chamber of the compressor main body 3. The oil feeding system 8 includes a temperature control valve 20 that adjusts a diversion ratio for an oil cooler 18 and a diversion ratio for a bypass pipe 19 according to a temperature of the oil. The oil feed type air compressor 1 includes pressure sensors 22A and 22B located in the oil feeding system 8, a discharge temperature sensor 11 located on the discharge side of the compressor main body 3, and a controller 9 that computes, when it is estimated that the diversion ratio for the oil cooler 18 is 100% from the temperature sensed by the discharge temperature sensor 11 exceeding a predetermined value Td1, a difference ?P between the pressure sensed by the pressure sensor 22A and the pressure sensed by the pressure sensor 22B and determines a deterioration state of the oil in reference to the difference ?P.

A gas compressor includes a compression mechanism, a separator tank that introduces lubricating oil to be supplied to the compression mechanism and a mixed fluid of a working fluid and lubricating oil discharged from the compression mechanism and separates the lubricating oil. An oil cooler cools the lubricating oil from the separator tank. An oil circulation path supplies cooled lubricating oil to the compression mechanism. The gas compressor includes a suction temperature sensor that detects suction temperature of the working fluid, a discharge pressure sensor that detects discharge pressure of the compressed working fluid, a rotation speed sensor that detects rotation speed of the motor. A lubricating oil state estimation unit estimates the temperature of the lubricating oil based on the detected suction temperature, discharge pressure, and rotation speed of the motor. The lubricating oil state estimation unit uses this result to estimate the deterioration state of the lubricating oil.