Abstract: A vehicle comprising a kinetic energy recovery system having a flywheel supported for rotation in a vacuum enclosure wherein a first vacuum pumping arrangement evacuates the vacuum enclosure and a second vacuum pumping arrangement of the vehicle evacuates the recovery system. The flywheel is supported for rotation on a common drive shaft with the first vacuum pumping mechanism.

Abstract: A kinetic energy recovery system is provided comprising a flywheel located in a first vacuum enclosure and a second vacuum enclosure comprising an inlet in fluid communication with the exhaust of the first vacuum enclosure and arranged to be maintained at a pressure less than atmosphere for reducing the pressure at the outlet of the first vacuum enclosure, the second vacuum enclosure comprising an exhaust through which gas can be pumped periodically at indeterminate intervals for maintaining the second vacuum enclosure at a pressure less than atmosphere. Thus an improved efficiency Kinetic energy system.

Abstract: A differentially pumped mass spectrometer system comprises a mass spectrometer having first and second pressure chambers through which, during use, ions are conveyed along a path. A pump assembly for differentially evacuating the chambers is attached to the mass spectrometer. The pump assembly comprises a housing attached to the mass spectrometer and a cartridge inserted into the housing. The cartridge has a plurality of inlets each for receiving fluid from a respective pressure chamber and a pumping mechanism for differentially pumping fluid from the chambers. The cartridge is inserted into the housing such that the pumping mechanism is inclined relative to the ion path, but with the cartridge protruding into the mass spectrometer to such an extent that at least one of the inlets at least partially protrudes into its respective chamber without crossing the ion path.

Abstract: A vacuum pump comprises a first pumping section (106), and, downstream therefrom, a second pumping section (108), The pump comprises a first pump inlet (120) through which fluid can enter the pump and pass through both the first and second pumping sections towards a pump outlet, and a second pump inlet (122) through which fluid can enter the pump and pass through only the second pumping section towards the outlet. The second pumping section (108) comprises an externally threaded rotor (109).

Abstract: A differentially pumped mass spectrometer system comprises a mass spectrometer having first and second pressure chambers through which, during use, ions are conveyed along a path. A pump assembly for differentially evacuating the chambers is attached to the mass spectrometer. The pump assembly comprises a housing attached to the mass spectrometer and a cartridge inserted into the housing. The cartridge has a plurality of inlets each for receiving fluid from a respective pressure chamber and a pumping mechanism for differentially pumping fluid from the chambers. The cartridge is inserted into the housing such that the pumping mechanism is inclined relative to the ion path, but with the cartridge protruding into the mass spectrometer to such an extent that at least one of the inlets at least partially protrudes into its respective chamber without crossing the ion path.

Abstract: A differentially pumped mass spectrometer system comprises a mass spectrometer having first and second pressure chambers through which, during use, ions are conveyed along a path. A pump assembly (10) for differentially evacuating the chambers (62, 66, 68) is attached to the mass spectrometer. The pump assembly comprises a housing (12) attached to the mass spectrometer and a cartridge (14) inserted into the housing. The cartridge has a plurality of inlets (16, 18, 20) each for receiving fluid from a respective pressure chamber (62, 68, 66) and a pumping mechanism (30, 32, 34) for differentially pumping fluid from the chambers. The cartridge is inserted into the housing such that the pumping mechanism (10) is inclined relative to the ion path (76), but with the cartridge protruding into the mass spectrometer to such an extent that at least one of the inlets (16, 18) at least partially protrudes into its respective chamber (62, 68) without crossing the ion path.

Abstract: A scroll compressor having a scroll wall arrangement with a fixed scroll having fixed scroll walls and an orbiting scroll having orbiting scroll wall, an inlet at a radially outer portion and an outlet at a radially central portion, a first flow path defined by the orbiting and fixed scroll walls and extending from the inlet to the outlet, gas entering through inlet at a pressure and exhausting through outlet at a second pressure higher than the first pressure. Scroll wall arrangement having a second inlet through which gas enters at a third pressure and follows a second fluid path where it is exhausted through the outlet at the second pressure to form two flow paths having respective inlets. The third pressure at which gas enters through inlet is different from the first pressure, and lower than the second pressure.

Abstract: A differentially pumped mass spectrometer system comprises a mass spectrometer having first and second pressure chambers through which, during use, ions are conveyed along a path. A pump assembly (10) for differentially evacuating the chambers (62, 66, 68) is attached to the mass spectrometer. The pump assembly comprises a housing (12) attached to the mass spectrometer and a cartridge (14) inserted into the housing. The cartridge has a plurality of inlets (16, 18, 20) each for receiving fluid from a respective pressure chamber (62, 68, 66) and a pumping mechanism (30, 32, 34) for differentially pumping fluid from the chambers. The cartridge is inserted into the housing such that the pumping mechanism (10) is inclined relative to the ion path (76), but with the cartridge protruding into the mass spectrometer to such an extent that at least one of the inlets (16, 18) at least partially protrudes into its respective chamber (62, 68) without crossing the ion path.

Abstract: A scroll compressor which comprises a scroll assembly comprising two scroll walls, and a drive for causing a relative orbiting motion between the scroll walls for compressing fluid on two fluid flow paths between an inlet and an exhaust of the scroll assembly. A first fluid flow path is formed between a wall surfaces of the scroll walls and a second fluid flow path is formed between another facing wall surfaces of the scroll walls. A first ambient clearance A1 is selected between the first two facing surfaces, and a second ambient clearance A2 is selected between the second two facing surfaces, and where the first and the second ambient clearances are selected independently from each other. Independent selection permits each ambient clearance to be designed according to its own performance requirements, to take into account thermal expansion and manufacturing tolerances.

Abstract: A scroll compressor which comprises a scroll assembly comprising two scroll walls, and a drive for causing a relative orbiting motion between the scroll walls for compressing fluid on two fluid flow paths between an inlet and an exhaust of the scroll assembly. A first fluid flow path is formed between a wall surfaces of the scroll walls and a second fluid flow path is formed between another facing wall surfaces of the scroll walls. A first ambient clearance A1 is selected between the first two facing surfaces, and a second ambient clearance A2 is selected between the second two facing surfaces, and where the first and the second ambient clearances are selected independently from each other. Independent selection permits each ambient clearance to be designed according to its own performance requirements, to take into account thermal expansion and manufacturing tolerances.

Abstract: A vacuum pump comprising a shaft rotatable by means of a motor, at least two spaced pump stages mounted on the shaft, a first pump inlet through which gas can pass for passage through all the pump stages for evacuating a first system and a second pump inlet through which gas can enter the pump at an inter-stage location for passage through only subsequent stages of the pump for evacuating a second system, said first and second systems each having a gas outlet flange for attachment to a first or a second pump inlet, in which the vacuum pump is mounted relative to the respective first and second systems such that the longitudinal axis of the shaft is inclined to each of the gas outlet flanges.