A liquid ring screw pump includes a housing with a suction inlet section and a pressure outlet section. Within the housing an Archimedes screw rotor is driven by a motor via a shaft. The inlet section and outlet section are each provided with connecting structure for suction and pressure piping respectively. The displacement CD of the screw rotor in relation to the center axis of the housing is determined by an equation based on the screw rotor radius, a minimum screw rotor core radius, and a variable k that is between 0.14 and 0.29.

A vacuum pump system comprising a main vacuum pump that is connected to a chamber that is to be evacuated. An auxiliary pump is connected to an outlet of the main vacuum pump. Furthermore, a sealing gas supply device is connected to the main vacuum pump. The sealing gas supply device is switched on and off with the aid of a control device as a function of a predetermined control variable. Additionally, a method for controlling the vacuum pump system.

A vacuum pump system comprising a main vacuum pump that is connected to a chamber that is to be evacuated. An auxiliary pump is connected to an outlet of the main vacuum pump. Furthermore, a sealing gas supply device is connected to the main vacuum pump. The sealing gas supply device is switched on and off with the aid of a control device as a function of a predetermined control variable. Additionally, a method for controlling the vacuum pump system.

A scroll compressor (100) comprises an orbiting scroll component (160); a fixed scroll component (150); sealing components (PS1, PS2, PS3, PS4, PS5, PS6), wherein the sealing components match a concave part (158) on the orbiting scroll component (50) so as to form a back pressure chamber (BC) together, and the sealing components are constructed to separate the back pressure chamber from a high-pressure side and a low-pressure side in the scroll compressor (100); and a leakage path (L), wherein the leakage path (L) is constructed to allow fluid in the back pressure chamber (BC) to leak.

A scroll compressor (100) comprises an orbiting scroll component (160); a fixed scroll component (150); sealing components (PS1, PS2, PS3, PS4, PS5, PS6), wherein the sealing components match a concave part (158) on the orbiting scroll component (50) so as to form a back pressure chamber (BC) together, and the sealing components are constructed to separate the back pressure chamber from a high-pressure side and a low-pressure side in the scroll compressor (100); and a leakage path (L), wherein the leakage path (L) is constructed to allow fluid in the back pressure chamber (BC) to leak.

A rotary screw vacuum pump 10 comprises a housing 12 that has a lower pressure inlet region 14 and a higher pressure outlet region 16 and two intermeshing screws 18 disposed in the chamber and configured to cooperably rotate to compress a gas in working chambers formed between them and the housing while pumping the gas from the lower pressure inlet region to the higher pressure outlet region. The housing 12 has a least one liquid inlet 20 to admit a sealing liquid to seal the working chambers. The intermeshing screws 18 comprise Quimby-type screws.

A screw compressor includes a housing having an inlet for receiving gas to be compressed by the compressor and an outlet for discharging pressurized compressed gas. A pair of meshing threaded rotors, each rotor having an axis and being rotatably received in the housing, each rotor having a first end near the inlet and a second end near the outlet. A bearing rotatably carrying each rotor about its axis and positioned near the first end and the second end of each rotor. A conduit formed in the housing in selectable fluid communication with at least one bearing and a force generating source from a pressurized fluid source, the force generating source selectably providing a force in a radial direction relative to the axis of the at least one bearing.

A screw compressor and a chiller unit are provided. An oil separator of the screw compressor may include an outer cylinder, an inner cylinder positioned inside the outer cylinder, and an introducing flow path. The upper end of the inner cylinder is held by the oil separator and the outer wall of the inner cylinder is held independently of the inner wall of the outer cylinder. The diameter of the inner wall of the outer cylinder may gradually be reduced along the swirl flow path. The refrigerant via the introducing passage swirls and goes down along the swirl flow path and is separated into gas refrigerant and oil. The separated gas refrigerant flows from the lower end of the inner cylinder into the inner cylinder and goes up, and the separated oil flows down along the inner wall surface of the outer cylinder.

A rotary piston compressor is disclosed, comprising a housing having an epitrochoidal shaped inner bore, peripheral inlet and exhaust ports located in the bore, and a rotary piston rotatably mounted within the housing. The central portion of each rotary piston flank is configured such that, at the closest point between the flank central portion and the housing between the exhaust port of the trailing compression cycle and the inlet port of the leading compression cycle, the radial spacing between the rotary piston flank and the housing is maintained such that, the volumes enclosed by the rotary piston on either side of the closest point in the respective trailing and leading compression cycles are substantially sealed from one another. The end portions of each rotary piston flank are configured such that radial spacing between the rotary piston flank and the housing exceeds to that between the central portion and the housing.

A rotary piston compressor is disclosed, comprising a housing having an epitrochoidal shaped inner bore, peripheral inlet and exhaust ports located in the bore, and a rotary piston rotatably mounted within the housing. The central portion of each rotary piston flank is configured such that, at the closest point between the flank central portion and the housing between the exhaust port of the trailing compression cycle and the inlet port of the leading compression cycle, the radial spacing between the rotary piston flank and the housing is maintained such that, the volumes enclosed by the rotary piston on either side of the closest point in the respective trailing and leading compression cycles are substantially sealed from one another. The end portions of each rotary piston flank are configured such that radial spacing between the rotary piston flank and the housing exceeds to that between the central portion and the housing.