Abstract: A mechanical kinetic vacuum pump with a stator (1), a rotor (6, 7) made from an aluminum or magnesium alloy and a rotor (6, 7) and a bearing shaft (3). The shaft (3) and the rotor (6, 7) are connected by a shrink- or screw-fit in a secure permanent connection. The rotor (6, 7) is made by spray forming. The main alloying component in the aluminum or magnesium alloy is silicon which is present in an amount such that the alloy has an expansion coefficient which essentially corresponds to the expansion coefficient of the shaft material.

Abstract: A reciprocating piston drive mechanism, especially for a reciprocating piston vacuum pump, includes a cylinder (3) embodied in a housing (12). A piston (4) is moved back and forth in the cylinder by an electromagnetic drive that has an electromagnet (11) on the stator side and at least one permanent magnet (18, 19) on the piston side. In order to increase service life of said drive mechanism, permanent magnets (15, 16) are also provided on the stator side. The piston permanent magnet(s) (18, 19) and the stator permanent magnets (15, 16) are configured and disposed in such a way that the piston (4) is magnetically biased to a substantially central axial position in the idle state.

Abstract: A friction vacuum pump (1) has at least one turbomolecular pump stage (6, 7) with a molecular pump stage (12, 13, 15) that is subsequently connected on the pressure side (3), and with a transition stage (23) mounted between the turbomolecular pump stage and the molecular pump stage. In order to improve the transition from the turbomolecular zone to the molecular zone, the transition stage has a flow section that is continuously tapered in the tangential by limiting surfaces (27, 28).

Abstract: A rotor (12) is mounted in a stator (14) with radial magnetic bearings (16, 19) and with an axial magnetic bearing (40) in a contactless manner. The axial magnetic bearing (40) produces an axial magnetic field with a magnet coil (40) and a yoke iron (44) mounted on the stator (14). An axially magnetized permanent magnet (50) is provided on the rotor (12), located approxaimately axially opposite the yoke iron (44). A permanently axially magnetized compensating magnet (54) is provided on the stator (14) and arranged axially opposite the permanent magnet of the rotor (50) and polarized in the opposite direction, such that the permanent magnet (50) of the rotor and the compensating magnet (54) repel each other. In a center position, the rotor is bias-free by compensating the forces of attraction between the permanent magnet of the rotor and the yoke iron. As a result, the center position of the rotor can be adjusted with relatively small magnet coil flows.

Abstract: A vacuum line (10) comprising a vacuum-tight flexible tube section (22) and a vibration damper (16) axially parallel to the flexible tube section (22) serves to connect tow vacuum devices (12, 14). The vibration damper (16) is an actively regulated axial magnetic bearing. Thereby, a vibration damper with good dampening properties is realized. By changing the regulation parameters, the vibration damper is adaptable and not subjected to any mechanical wear. The transmission of structure-borne noise is avoided by the contactless vibration dampening.

Abstract: A vacuum pump has two shafts (3, 4) and two rotors (1, 2) which co-operate with each other and which are fixed to the shafts. The rotors are cantilevered on the shafts. The rotors are fixed to the shafts in a manner which is devoid of backlash, even during temperature changes. In order to achieve this, the shafts (3, 4) are made of a material having a modulus of elasticity which is as high as possible, e.g., steel. The rotors (1, 2) are made of a material having a density which is as low as possible, e.g., aluminum or a titanium alloy. Structures (8; 11, 12, 13; 14, 15; 25, 27; 38, 41; 43, 44, 45; etc.) are provided to ensure that the rotors (1, 2) are fixed to the shafts (3, 4) in a manner which is devoid of backlash at all operating temperatures.

Abstract: A magnetic bearing for rapidly rotating machines (1), in particular, for turbo compressors, drag vacuum pumps, or similar, includes two bearings (3, 4), each with a stator magnetic-ring set (5, 7) and a rotor magnetic-ring set (6, 8). Movement of the rotor is damped by magnetic-ring sets (5, 6; 7, 8) arranged concentrically to each other. The stator magnetic-ring set (5 or 7) is arranged externally and the rotor magnetic-ring set (6 or 8) is arranged internally. Non-magnetic elements with good electrical conducting properties (32, 54, 55) are connected to the outer circumference surfaces of at least one part of the magnetic ring of each of the stator-side magnetic-ring sets (5, 7).

Abstract: A vacuum pump (1) includes a housing (2) in which a suction inlet opening (5) is defined. A vibration absorber (7) includes a suspension body (8) and an absorber jacket (9). The housing (2) of the vacuum pump (1) is connected directly to one end of the suspension body (8) in vacuum-tight connection and an opposite end of the suspension body carries a connecting port (14). By connecting the suspension body directly with the housing without mechanically releasable interconnection elements, the overall height of the pump and suspension body assembly is reduced.

Abstract: A dry compressing vacuum pump (1) has a continuous or graduated inner compression. A gas ballast device (8) selectively adds a ballast gas to a pumped gas. The gas ballast device has an isolating valve (11), a non-return valve (12) which prevents the escape of gases from the pump through the gas ballast device to the outside, and a pressure differential valve (13).

Abstract: A screw vacuum pump (1) has shafts (7, 8) and rotors (3, 4) secured to the shafts. Each rotor has a central hollow chamber (31) which receives the shaft or contains in built-in components rotating along with the rotor to define a relatively thin annular slot segment (32) for cross-flow circulation of coolant. The annular slot segment is disposed between the built-in components and an inner wall of the rotor's hollow chamber and between a suction side and a delivery side of the rotor. Separate feed and discharge lines (41, 55, 63, 77, 78, 81, 89, 99, 101, 103) circulate the coolant through the annular slot segment in such a way that the coolant remains cavitation-free and bubble-free.

Abstract: A reciprocating piston drive mechanism, especially for a reciprocating piston vacuum pump, includes a cylinder (3) embodied in a housing (12). A piston (4) is moved back and forth in the cylinder by an electromagnetic drive that has an electromagnet (11) on the stator side and at least one permanent magnet (18, 19) on the piston side. In order to increase service life of said drive mechanism, permanent magnets (15, 16) are also provided on the stator side. The piston permanent magnet(s) (18, 19) and the stator permanent magnets (15, 16) are configured and disposed in such a way that the piston (4) is magnetically biased to a substantially central axial position in the idle state.

Abstract: A ball bearing (18) that carries a rotor side portion of a rotor shaft (16) includes an inner race (23), an outer race (24), and a plurality of balls (25). The inner race has an enlarged end face (S1) which supports a supporting part (22) of a rotor (13). The enlarged end face has a diameter (D1) which is at least as large as a reference diameter (D3) minus 34% of a diameter of the balls (25). The flexural strength of the rotor shaft is increased at the location of the ball bearing (18). The natural bending frequency also increases and is caused to be above an operating frequency of the rotor shaft. Resonances are also avoided.

Abstract: A seal is disposed between a rotating part and a stationary part. At least one of the parts is provided with projections which protrude into the seal gap. The seal gap (5) extends approximately radially so that both parts are provided with projections which extend in an axial direction, which are located concentrically in relation to the axis of rotation of the rotating parts and which engage with each other. Said projections are configured in the form of rows of blade-like elements. This effectively seals approximately radially extending seal gaps.

Abstract: A friction vacuum pump for use in a system for regulating the pressure in a vacuum chamber includes a multistage turbomolecular vacuum pump section (6) whose stages each consist of a row of stator vanes and rotor vanes (14 or 13). The pump regulates the pressure of heavy gases or of a gas mixture containing heavy gases. To this end, the friction vacuum pump (1) is equipped with a molecular pump section (11) located on the fore-vacuum side and a space (21, 22, 23), in which the pump action is interrupted. The space is provided in the transition area from the turbomolecular vacuum pump section (6) to the molecular pump section (11) or in the transition area from the molecular flow to viscous flow.

Abstract: The radial turbo-blower comprises a stator (35) that is housed in a stator housing (10) and a rotor (13) that rotates within a pump housing (11). The rotor (13) comprises a cavity (23) with a bearing arrangement (26) that is received by a protruding bearing pin (25). A pump chamber (12) is separated from a stator chamber (22) by a thin partition wall (21). Thereby, an atmospheric pressure is maintained in the stator chamber (22). The blower consists of few components and has a short structural length. It is substantially maintenance-free and the rotor area is protected from being contaminated by oil.

Abstract: A molecular vacuum pump (1) has a stator unit (9) and a rotor unit (8) disposed within a housing (2). A narrow gap is maintained during operation between the stator unit (9) and the rotor unit (8). The stator unit (9) and the rotor unit (8) are coupled together with respect to vibration to form a rotor/stator system (3). Elastic vibration elements (4, 5) mount the rotor/stator system in the housing such that the rotor/stator system rotates as a unit relative to the housing. Because the rotor and stator units vibrate together rather than relative to each other, very small, precise tolerances are maintained between them.

Abstract: A molecular vacuum pump (1) includes a stator unit (9) which has a stator blade package including one or more rows of stator blades (42), and a rotor unit (8) which has rotor blade package including one or more rows of rotor blades (41). The rotor blades (41) and the state blade (42) intermesh with each other in the functionally assembly state. The rotor blades 941) include slots (61) whose arrangement, depth and width are selected such that the stator unit (9) and the rotor unit (8) may be screwed together or unscrewed from one another. Alternatively, the stator blades (42) include slots (61) whose arrangement, depth and width are selected such that the stator unit (9) and the rotor unit (8) may be screwed together or unscrewed from one another.

Abstract: A friction pump (1), such as turbomolecular pump, includes a steel housing (2) in which a steel shaft (15) is supported by a bearing (16). A rotor (4) with a central bore (21) is mounted on the shaft. In order to reduce the risk of the joint area between the rotor and the shaft becoming loose, a ring groove (26, 31) which encompasses the joint area between the rotor is provided in an area adjacent at least one of the faces of the rotor. A reinforcing ring (34, 35, 38) of a high strength, low thermal expansion material encompasses one of a thrust member (28) and cylindrical rotor sections (32, 37) adjacent the shaft.

Abstract: During the pumping of corrosive gases, it is advantageous to admit a seal gas to endangered pumping chambers at a lower flow rate and a higher pressure than the corrosive gases. Inert gas from a supply (3) has its pressure reduced by a pressure reducer (6). An on/off valve (7) controls a flow of the inert gas through a flow restriction (8) which restricts the flow of inert gas to appropriate sealing gas rates at an outlet (4). After pumping the corrosive gas, a control valve (12) in a bypass line (11) causes the inert gas to be supplied to the outlet (4) at a higher flow rate for purging the pump.

Abstract: A cooled screw vacuum pump has a housing (4) two rotating systems (5, 6) consisting each of a screw rotor (5) and a shaft (6), a floating device supporting the rotors having, on each shaft, two mutually spaced bearings (7, 8) and an empty space (31) arranged in each rotor (5) open on the bearing side, wherein is respectively located an element cooling the rotor internally. In order to improve cooling it is suggested that the bearing (7) of the support located on the rotor side, is placed outside the rotor (5) empty space (31), such that in said empty space (31) there is more room available for obtaining efficient cooling.