Abstract: A vacuum pump comprises pumping elements arranged in a pumping chamber. An electric motor drives the pumping element. A frequency inverter is provided for changing the rotational speed of the electric motor. The frequency inverter is arranged in a frequency inverter housing immediately connected to the pump housing. An air cooler and a liquid cooler are arranged in the frequency inverter housing to cool the frequency inverter.

Abstract: A rotary vacuum pump includes a suction chamber (12) in a housing (10). A rotor (14) is eccentrically mounted in the suction chamber (12). Sliding vanes (18) are connected to the rotor (14). Further, a discharge channel (30) is connected to the suction chamber (12) and to an oil chamber (32). A valve (38) is disposed between the discharge channel (30) and the oil chamber (32) in order to prevent the medium from flowing back from the oil chamber (32) into the suction chamber (12). At least one compensating channel (50) is connected to the discharge channel (30) and to the oil chamber (32).

Abstract: In order to provide a simple and energy-efficient rough pumping method for a displacement pump (10), intended to generate a maximum differential pressure (?Pmax) between the inlet (18) and the outlet (20) of the displacement pump (10), the rotational speed (?) of the displacement pump (10) is adjusted such that the maximum differential pressure (?Pmax) to be generated that the power input (3, 4) of the displacement pump (10) approximates the minimum power (2) physically required for compressing the gas in order to establish the maximum differential pressure (?Pmax).

Abstract: A multi-inlet vacuum pump has a first pump device (10) and a second pump device (12). The first pump device (10) includes a first rotor element (18) having a plurality of first rotor discs (20, 21) arranged consecutively in the delivery direction (36). The second rotor disc includes a second rotor element (26) having a plurality of second rotor discs (28) arranged consecutively in the delivery direction (36). A first fluid flow (34) is suctioned through a main inlet (32) by the first pump device (10) and delivered in the direction of the second pump device (12). A second fluid flow (40) is suctioned through an intermediate inlet (38) by the second pump device and delivered in the direction of a pump outlet. The diameter of the last rotor disc (21) of the first pump (10) substantially corresponds to the diameter of the first rotor (28) of the second pump device (12).

Abstract: A multi-inlet vacuum pump includes a first pump device (10) including a first rotor element (18) with a plurality of first rotor disks (20) serially arranged in the conveying direction (36), and a second pump device (12) including a further rotor element (26) with a plurality of second rotor disks (28) serially arranged in the conveying direction (36). A diameter of the second rotor disks (28) is at least partially larger than a diameter of the first rotor disks (20). A main inlet (32) sucks in a first fluid stream (34) with the first pump device (10). The first fluid stream (34) is conveyed in the direction of the further pump device (12). An intermediate inlet (38) sucks in a second fluid stream (40) with the second pump device (12). The second fluid stream (40) is conveyed in the direction of a pump outlet. A process of merging the two fluid streams (34,40) will occur within the second pump device (12), preferably between two adjacent second rotor disks (28) of the second pump device (12).

Abstract: A turbomolecular pump has a rotor element in a housing. The rotor element is arranged on a rotor shaft. The rotor shaft is supported by two bearing elements in the housing. The bearing element on the high-vacuum side is constructed as a roller bearing. In order to guarantee a pressure in the area of the bearing element that is acceptable for the bearing element constructed as a roller bearing, the bearing element is arranged in a chamber. The chamber is connected via a channel to the pre-vacuum area and sealed relative to the high-vacuum area by a gasket.

Abstract: A vacuum pump, in particular a turbomolecular pump or a multi-inlet pump, includes a rotor shaft (12) that supports at least one rotor device (14). The rotor shaft (12) is mounted on the pressure side by way of a bearing arrangement (56) and on the suction side by way of a bearing arrangement (30). The suction-side bearing arrangement (30) is disposed in a high-vacuum area (22) and includes an electromagnetic bearing. Preferably, a coil (32) of the electromagnetic bearing is disposed in a recess (38) of a housing element (40). The recess (38) is pressure-encapsulated, in particular by a tubular closure element (42).

Abstract: A stator-rotor arrangement for a vacuum pump, in particular for a turbomolecular pump, includes a plurality of stator disks (18) that cooperate with a rotor element (14). The stator disks (18) are disposed between rotor disks (16). The stator disks (18) are held by way of stator rings (20, 22). At least two of the stator rings (20) include protrusions (24) that are connected together by way of holding elements (28, 30). This makes pre-installation of the rotor-stator arrangement (12) or placement of the rotor-stator arrangement (12) in a housing (10) possible. The protrusions (24) are disposed in the area of corners (32) of the housing (10).

Abstract: A method for determining the fatigue of the pump rotor of a gas turbopump comprises the following method steps: continuous determination of the rotational speed (n) of the pump rotor, determination of the local rotational speed maxima and minima of a temporal rotational speed profile under consideration, association of the rotational speed maxima and minima with each other to form pairs, determination of a pair fatigue value (L) for each of the rotational speed pairs, and accumulation of all pair fatigue values (L) to form a total fatigue value (Ltot). In this manner it is possible to determine the cyclic stress for the pump rotor of a vacuum pump and to include it in the calculation of a total fatigue value.

Abstract: In order to provide an improved multistage oil separator, in particular for the use with compressors in cryogenics, the oil separator includes a housing (10) having a gas inlet (18) and a gas outlet (20), and at least two filter elements (26, 28) arranged as a cascade in the housing between the gas inlet (18) and the gas outlet (20).

Abstract: A vacuum pump, in particular a pump of the type with rolling bodies, includes rotary bodies (12) arranged in a suction chamber (10). The pressure side (30) of the pump is connected to the suction side (20) by a connecting channel (22). In the connecting channel (22), a valve (24) is arranged which closes a through opening (32). On exceeding a set pressure difference between the pressure side (30) and the suction side (20), the valve opens automatically. In order to reduce the necessary space and to reduce the switching noise from the valve, the valve body is embodied as a valve flap (28).

Abstract: A multi-stage pump rotor (10) for a turbomolecular pump has at least two separate blade disk rings (17), each having a motor ring (12) and at least one blade disk (14). A cylindrical reinforcement pipe (18), which surrounds the rotor rings (12) of the blade disk rings (17) on the outside without clearance, is provided between the blade disks (14) of adjacent blade disk rings (17). The reinforcement pipe (18) absorbs a large part of the tangential forces occurring during operation such that the pump rotor (10) has improved stability at high rotor speeds.

Abstract: A rotary vacuum pump includes a suction chamber (12) in a housing (10). A rotor (14) is eccentrically mounted in the suction chamber (12). Sliding vanes (18) are connected to the rotor (14). Further, a discharge channel (30) is connected to the suction chamber (12) and to an oil chamber (32). A valve (38) is disposed between the discharge channel (30) and the oil chamber (32) in order to prevent the medium from flowing back from the oil chamber (32) into the suction chamber (12). At least one compensating channel (50) is connected to the discharge channel (30) and to the oil chamber (32).

Abstract: A rotary vacuum pump includes a suction chamber (12) in a housing (10). A rotor (14) is eccentrically mounted in the suction chamber (12). Sliding vanes (18) are connected to the rotor (14). Further, a discharge channel (30) is connected to the suction chamber (12) and to an oil chamber (32). A valve (38) is disposed between the discharge channel (30) and the oil chamber (32) in order to prevent the medium from flowing back from the oil chamber (32) into the suction chamber (12). At least one compensating channel (50) is connected to the discharge channel (30) and to the oil chamber (32).

Abstract: In order to provide an improved multistage oil separator, in particular for the use with compressors in cryogenics, the oil separator includes a housing (10) having a gas inlet (18) and a gas outlet (20), and at least two filter elements (26, 28) arranged as a cascade in the housing between the gas inlet (18) and the gas outlet (20).

Abstract: A multi-inlet vacuum pump has a first pump device (10) and a second pump device (12). The first pump device (10) includes a first rotor element (18) having a plurality of first rotor discs (20, 21) arranged consecutively in the delivery direction (36). The second rotor disc includes a second rotor element (26) having a plurality of second rotor discs (28) arranged consecutively in the delivery direction (36). A first fluid flow (34) is suctioned through a main inlet (32) by the first pump device (10) and delivered in the direction of the second pump device (12). A second fluid flow (40) is suctioned through an intermediate inlet (38) by the second pump device and delivered in the direction of a pump outlet. The diameter of the last rotor disc (21) of the first pump (10) substantially corresponds to the diameter of the first rotor (28) of the second pump device (12).

Abstract: In order to provide a simple and energy-efficient rough pumping method for a displacement pump (10), intended to generate a maximum differential pressure (?Pmax) between the inlet (18) and the outlet (20) of the displacement pump (10), the rotational speed (?) of the displacement pump (10) is adjusted such that the maximum differential pressure (?Pmax) to be generated that the power input (3, 4) of the displacement pump (10) approximates the minimum power (2) physically required for compressing the gas in order to establish the maximum differential pressure (?Pmax).

Abstract: The invention relates to a process for the coating of objects made of valve metals selected from aluminum, magnesium, titanium, niobium and/or zirconium and their alloys with an oxide ceramic layer formed from the metal which has a thin barrier layer as a boundary layer towards the metal whose surface has been coated with polymers, characterized in that said polymers are introduced into the capillary system of the oxide ceramic layer in the form of dimers or halogenated dimers of general formula I wherein R1 represents one or more hydrogen or halogen residues; each R2 represents hydrogen or halogen; and R3 commonly represent a corresponding xylylene residue for completing a dimeric structure; by vacuum coating, followed by polymerizing the dimers.

Abstract: The invention refers to a mass spectrometer arrangement (10) comprising a housing (86) having a mass spectrometer forevacuum vacuum chamber (20) with a mass spectrometer forevacuum outlet (30), at least two mass spectrometer high-vacuum vacuum chambers (21, 22, 23), and an integrated turbomolecular pump (12) connected with the high-vacuum vacuum chambers (21, 22, 23) and having a forevacuum outlet (89). The two forevacuum outlets (30, 89) open into a common forevacuum chamber (98) in the housing (86), which in turn opens into a housing outlet (88).