A progressive cavity pump (PCP) system includes a PCP with a rotor rotatably disposed in a stator, a permanent magnet motor, sucker rod(s), and a control system. The rotor is coupled to one of the sucker rods via a high-torque connection that allows for counter clockwise rotation without loosening the connection between the rotor and sucker rod. The control system operates the system in a production mode by rotating the rotor clockwise. Upon manual input by a user, or automatic triggering when protections settings of the control system call for a shutdown or cleanout or when the control system senses an imminent pump shutdown, the control system operates the system in a reverse mode by rotating the rotor counterclockwise. The reverse mode pumps fluids and suspended solid particles down into the well prior to pump shutdown to inhibit the solids from clogging the pump or preventing the pump from restarting.

A pumping method in a pumping system comprises: a main vacuum pump with a gas inlet port connected to a vacuum chamber and a gas outlet port leading into a conduit before coming out into the gas outlet of the pumping system, a non-return valve positioned in the conduit between the gas outlet port and the gas outlet, and an auxiliary vacuum pump connected in parallel to the non-return valve. The main vacuum pump is activated in order to pump the gases contained in the vacuum chamber through the gas outlet port, simultaneously the auxiliary vacuum pump is activated and continues to operate all the while that the main vacuum pump pumps the gases contained in the vacuum chamber and/or all the while that the main vacuum pump maintains a defined pressure in the vacuum chamber. Also included is a pumping system.

A dry-type primary vacuum pump includes an injection device to distribute a purging gas in the pumping stages. The injection device includes: a first pressure sensor arranged on a common portion of the distributor, a second pressure sensor arranged on each branch of the distributor, and a control unit to generate a pulse width modulation command signal for the control of the regulation valves independently of one another as a function of the pressure measurement differences between the first pressure sensor and the second pressure sensors.

A gas treatment device treats, at atmospheric pressure, the gases pumped by at least one rough pumping device. The gas treatment device includes a treatment chamber and at least one discharge pipe to connect a discharge of the at least one rough pumping device to an inlet of the treatment chamber. The gas treatment device further includes at least one auxiliary pumping device to lower the pressure in the at least one discharge pipe, situated less than 1 meter from the inlet of the treatment chamber, such as less than 50 cm.

A compressor may include a shell assembly, first and second scrolls, a floating seal assembly, a modulation-valve ring, and a modulation-control-valve assembly. The shell assembly may define a suction-pressure region. The first scroll may include a discharge passage, a modulation port, and a biasing passage. The modulation-valve ring may cooperate with the floating seal assembly and the first scroll to define an axial-biasing chamber in fluid communication with the biasing passage. The modulation-valve ring may be axially displaceable between a closed position to close the modulation port and an open position to open the modulation port. The modulation-control-valve assembly may be mounted to the modulation-valve ring and may be movable between a first position corresponding to the closed position and a second position corresponding to the open position.

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.

An automatic transmission has an oil pump driven by a travelling driving source. An air vent structure that expels air bubbles contained in automatic transmission fluid during pump operation has an air vent hole whose one end communicates with an outlet port of the oil pump and whose other end opens toward the oil pan. An air vent tube is connected to an opening end of the air vent hole. The air vent tube is extended up to a strainer lower side gap area located between a strainer and the oil pan, and a tube opening end of the air vent tube is placed in oil of the automatic transmission fluid.

A digital pressure switch is configured to be connected to a fluid pump. The digital pressure switch includes a pressure sensor configured to measure pressure inside a closed system, one or more relays configured to be connected to the fluid pump for activation and deactivation of the fluid pump, an amperage sensor configured to measure an amperage draw of an electric motor of the fluid pump, and a controller configured to process data from the pressure sensor and/or data from the amperage sensor and to activate or deactivate the motor of the fluid pump based on the data from the pressure sensor and/or the data from the amperage sensor, using the relays.

Variable displacement pump has first control hydraulic chamber 21 giving force to cam ring 5 in direction that decreases volume variation of each pump chamber 13 by internal pressure, second control hydraulic chamber 22 giving force to cam ring in direction that increases volume variation of each pump chamber by internal pressure, first seal surface 44 formed on both end surfaces of cam ring, which are in sliding-contact with both opposing inside surfaces of pump body 1 and cover member 2, and sealing gap between each pump chamber and first control hydraulic chamber, and second seal surface 45 sealing gap between each pump chamber and second control hydraulic chamber at outlet section side. Radial direction width W2 of second seal surface is greater than that W1 of first seal surface. Increase in weight of the pump can be suppressed while suppressing increase in pump control pressure against intention of control.

Disclosed are a variable capacity compressor operation mode determination method and device, a variable capacity compressor and an air conditioner. The variable capacity compressor operation mode determination method includes: detecting a current value of a compressor at present as A1 before switching an operation mode of the compressor; detecting the current value of the compressor at present as A2 after switching the operation mode of the compressor and reaching a preset time; comparing A1 and A2, determining that the switching of the operation mode of the compressor is successful when a ratio relationship between A1 and A2 satisfies a preset condition, and determining that switching of the operation mode of the compressor is failed when the ratio relationship between A1 and A2 dissatisfies a preset condition.