A scroll compressor of an air conditioner includes a refrigerant discharge tube through which refrigerant discharged to an inner space of a casing is discharged into a refrigeration cycle. The scroll compressor further including a venturi tube disposed adjacent to the refrigerant discharge tube in the inner space of the casing, and a liquid refrigerant discharge tube having a first end connected to the venturi tube and a second end opposite to the first end and communicating with the inner space of the casing at a lower side of the refrigerant discharge tube, where liquid refrigerant can be suppressed from excessively stagnating in the inner space of the casing.

The present invention relates to a pumping method in a pumping system (SP) comprising: a primary dry screw-type vacuum pump (3) with a gas entry orifice (2) connected to a vacuum chamber (1) and a gas exit orifice (4) leading into a conduit (5) before coming out into the gas outlet (8) of the pumping system (SP), a non-return valve (6) positioned in the conduit (5) between the gas exit orifice (4) and the gas outlet (8), and an ejector (7) connected in parallel to the non-return valve (6). According to this method, the primary dry screw-type vacuum pump (3) is put into operation in order to pump the gases contained in the vacuum chamber (1) through the gas exit orifice (4); in a simultaneous way, the ejector (7) is fed with working fluid, and the ejector (7) continues to be fed with working fluid all the time that the primary dry screw-type vacuum pump (3) pumps the gases contained in the vacuum chamber (1) and/or all the time that the primary dry screw-type vacuum pump (3) maintains a defined pressure in the vacuum chamber (1). The present invention also relates to a pumping system (SP) able to be used for implementing this method.

A system and method for increasing the capacity and efficiency of natural gas liquefaction processes by debottlenecking the refrigerant compression system. A secondary compression circuit comprising at least one positive displacement compressor is provided in parallel fluid flow communication with at least a portion of a primary compression circuit comprising at least one dynamic compressor.

An air compressor unit for vehicle (2) includes an air compressor (13) for compressing sucked air, an electric motor (14) for driving the air compressor (13), an after-cooler (17) for cooling compressed air generated in the air compressor (13) and an after-cooler cooling fan (18) for generating cooling air for the after-cooler (17) by being driven by a drive force of the electric motor (14). The air compressor (13) and the electric motor (14) are arranged one above the other.

A pump device having a drive shaft which has a drive section that can be coupled with a drive system. The pump device includes a vacuum pump that can be driven by the drive shaft. The vacuum pump includes a rotor and at least one blade that can be moved in radial direction in the rotor and that divides pressure chambers. The pump device also includes a lubrication pump that can be driven by the drive shaft. The vacuum pump is arranged between the drive section and the lubrication pump. A locking device is provided between the rotor and the lubrication pump in which, when activated, the at least one blade remains in a radially internal position when the rotor is rotating.

A rough vacuum pump system includes a primary vacuum pump and a secondary vacuum pump. The primary vacuum pump is an oil-free positive displacement pump, and has an inlet opening, an outlet opening, a compression stage between the inlet and outlet openings, and an intermediate gas passageway that connects to a gas flow path running through the compression stage. The secondary vacuum pump is connected to the intermediate gas passageway of the primary vacuum pump. The compression ratio of the primary and secondary vacuum pumps operating in combination is greater than that of the compression ratio of either of the primary and secondary vacuum pumps operating individually. A vacuum apparatus includes a tracer gas detector connected to an inlet of the primary vacuum pump.

A screw pump comprising a housing defining a chamber and two screw rotors. Wherein each screw rotor comprises a rotor shaft and at least two displacement elements connected with the rotor shaft. Each displacement element having at least one helical protrusion. One of the displacement elements is a suction-side displacement element arranged in a suction-side section of the chamber. Another one of the displacement elements is a pressure-side displacement element arranged in a pressure-side section of the chamber. The suction-side displacement element is designed tapering in the conveying direction. The clearance between the pressure-side displacement element and the pressure-side section of the chamber at least partly decreases in the conveying direction. Furthermore, a screw rotor, a method of manufacturing a screw rotor and a use of a screw pump or a screw rotor.

A compressor includes a housing, and a drive assembly, a compression assembly and an expansion assembly which are provided in the housing; the compression assembly is connected to and driven by the drive assembly, and is configured to perform multi-stage compression on a refrigerant under drive of the drive assembly; the expansion assembly is connected to the drive assembly and is configured to expand the refrigerant compressed by the compression assembly. A refrigeration cycle device includes the above-mentioned compressor.

A vacuum pump system includes a secondary pumping mechanism incorporated into a stationary portion of a scroll pump. The stationary portion includes the stationary plate scroll of the scroll pump and defines a gas passageway in which the secondary pumping mechanism is disposed. The gas passageway is connected to a gas flow path through the scroll pump at a location upstream of an exhaust check valve of the scroll pump. The secondary pumping mechanism is displaceable within the gas passageway to draw residual gas in the compression stage upstream of the check valve into the gas passageway, and may pump the residual gas back out through the exhaust check valve, to evacuate residual gas from the compression stage.

The invention relates to a turbine engine, such as a turbojet engine or a turboprop engine of an aeroplane, including at least one oil circuit (8) and cooling means (16) for cooling the oil of said circuit (8), the cooling means (16) including a refrigerant circuit (17) provided with a first heat exchanger (18) capable of exchanging heat between the refrigerant and the air and forming a condenser, a second heat exchanger (19) capable of exchanging heat between the refrigerant and the oil of the oil circuit and forming an evaporator, a pressure reducer (20), a compressor (21) and first regulator means (31) capable of regulating the pressure of the refrigerant entering the first exchanger (18).