Abstract: A turbomolecular pump includes a plurality of alternatively axially arranged one behind another, rotor and stator discs (8,9) provided with blades (10), with the blades (10) located in vicinity of the high vacuum side (2) having a blade angle (?) that is steeper than blade angle (?) of the blades (10) located in vicinity of the vacuum side (3), and with the blade angle (?) of the blades (10) located in the vicinity of the vacuum side (3) amounting to less than 8°.

Abstract: A gas friction pump including stationary (6) and rotatable (5), secured on a rotatable rotor shaft (4), pump-active elements, wherein the rotor shaft (4) and the rotatable pump-active elements (5) form components of the rotor, and the rotor shaft (4) is supported by two, spaced from each other, radial bearings (8, 9), of which one is located closer to the gravity center of the rotor than the other, and an axial bearing (16), characterized in that the radial bearing (9), which is located closer to the gravity center of the rotor, is formed as a gas bearing. In an advantageous embodiment, the gas bearings are formed as modules and can be brought into engagement with a cylindrical housing section and secured.

Abstract: A gas friction pump, comprising stationary pump-active components (14) and rotatable pump-active components (15) secured on a rotatable rotor shaft (4), wherein the rotor shaft is supported with a bearing (5) at the high-vacuum-side end and a bearing arrangement at a fore-vacuum side end, characterized in that the high-vacuum side bearing is formed as a conventional bearing, and the fore-vacuum bearing arrangement contains at least one gas bearing. In an advantageous embodiment, the gas bearing is formed as a module and can be brought in engagement with a cylindrical portion of the housing and secured therein.

Abstract: A vacuum pump system for delivering light gases and including at least one high-vacuum pump and at least one intermediate pump connected directly with the outlet of the high-vacuum pump and with small conductance losses.

Abstract: A gas friction pump, including a housing having a suction opening, a gas outlet opening, and a plurality of rotatable and stationary components arranged in the housing and having a pump-active structure for pumping gases and maintaining a pressure ratio, and an additional gas inlet formed as a longitudinal opening extending, in a longitudinal direction thereof, over a portion of an outer edge of a rotatable component.

Abstract: A gas friction pump including a housing (1) having a suction opening (2) and a gas outlet opening (3), rotor (12) and stator (14) components arranged in the housing (1) for delivery of gases and for obtaining a pressure ratio; and an additional, at least one-stage, concave pump unit (20, 30, 40) provided at a side of the suction opening (2) and having a gas delivery structure, with the additional pump unit (20, 30, 40) being so formed that gas delivery takes place in a radial direction, and with rotor components (21, 31, 41) of the additional pump unit (20, 30, 40) being supported on the same rotor shaft (4) as the rotor components of the pump itself.

Abstract: A gas friction pump including a plurality of pumping active rotor and stator components arranged in the pump housing for delivery of gases and for producing a compression ration and having a diameter larger than a diameter of the suction opening formed in the housing, and a modified rotor component located adjacent to the suction opening and having a radial extent which increases starting from the suction opening in a direction of a radial extent of the pumping active rotor and stator components.

Abstract: A gas friction pump including a housing having a suction opening and an exhaust opening, main rotor and stator components arranged in the housing and cooperating with each other for delivering gases and for producing a pressure difference, and an auxiliary pumping unit provided at a side of the suction opening and having a gas delivery structure that provides for gas delivery in a radial direction, with the auxiliary pumping unit being formed of at least one stage and having auxiliary rotor and stator components, with the auxiliary rotor components being supported on the shaft which supports the main rotor components.

Abstract: A vacuum pump, including a housing having inlet and outlet; a shaft arranged in the housing and supported bearing provided in the housing, drive for rotating the shaft; and a plurality of pumping units arranged in the housing and formed each of rotational and stationary gas delivery components with the rotational components being supported on the shaft and the stationary components being connected with the housing, at least one of the pumping units consisting of a plurality of connected parallel to each other and arranged one after another in an axial direction, molecular pumping stages with each pumping stage being formed based on Gaede principle; with the molecular pumping stages being connected with each other in common connection channels.

Abstract: A gas friction pump, including a housing having a suction opening, a gas outlet opening, and a plurality of rotatable and stationary components arranged in the housing and having a pump-active structure for pumping gases and maintaining a pressure ratio, and an additional gas inlet formed as a longitudinal opening extending, in a longitudinal direction thereof, over a portion of an outer edge of a rotatable component.

Abstract: A gas friction pump including a housing (1) having a suction opening (2) and a gas outlet opening (3), rotor (12) and stator (14) components arranged in the housing (1) for delivery of gases and for obtaining a pressure ratio; and an additional, at least one-stage, concave pump unit (20, 30, 40) provided at a side of the suction opening (2) and having a gas delivery structure, with the additional pump unit (20, 30, 40) being so formed that gas delivery takes place in a radial direction, and with rotor components (21, 31, 41) of the additional pump unit (20, 30, 40) being supported on the same rotor shaft (4) as the rotor components of the pump itself.

Abstract: A vacuum pump including a housing having a suction flange and an outlet opening, a plurality of stationary and rotatable pump-active elements arranged in the housing, a rotor shaft for supporting the rotatable elements, a system of gas bearings for supporting the rotor shaft, with the gas bearings being substantially formed of stator elements with gas delivery conduits and gas outlets, and a system of resilient elements for connecting the stator elements with the bearing housing.

Abstract: A gas friction pump including a plurality of pumping active rotor and stator components arranged in the pump housing for delivery of gases and for producing a compression ration and having a diameter larger than a diameter of the suction opening formed in the housing, and a modified rotor component located adjacent to the suction opening and having a radial extent which increases starting from the suction opening in a direction of a radial extent of the pumping active rotor and stator components.

Abstract: A gas friction pump including a housing having a suction opening and an exhaust opening, main rotor and stator components arranged in the housing and cooperating with each other for delivering gases and for producing a pressure difference, and an auxiliary pumping unit provided at a side of the suction opening and having a gas delivery structure that provides for gas delivery in a radial direction, with the auxiliary pumping unit being formed of at least one stage and having auxiliary rotor and stator components, with the auxiliary rotor components being supported on the shaft which supports the main rotor components.

Abstract: A vacuum apparatus including at least one vacuum pump having at least one stage and high-vacuum and fore vacuum connections, and a connection line communicating a point located between the high vacuum and fore vacuum connections with the high vacuum connection; and a method for controlling a suction speed of the at least one vacuum pump.

Abstract: A gas friction pump including a rotor located in the pump housing and formed of a plurality of coaxial first cylindrical elements, and a stator located in the housing and formed of a plurality of second cylindrical elements coaxial with the first cylindrical elements and surrounding respective first cylindrical elements, with the first cylindrical elements or the second cylindrical elements having smooth inner and outer surfaces, and another ones of the first cylindrical elements and the second cylindrical elements have a plurality of parallel discharge channels formed on their inner and outer surfaces, arranged one beneath another and separated by a respective plurality of webs, the parallel discharge channels defining a plurality of parallel discharge chambers forming a plurality of parallel operating pumping chambers for pumping gas form the suction port to the discharge port.

Abstract: A magnetic bearing arrangement for a rotor of a D.C. electric motor, which is rotated due to cooperation of a permanent magnet provided on the rotor and stator coils, and including a magnetic bearing, and at least one additional coil arrangement provided in a region of the permanent magnet at a side of a stator of the electric motor, and in which a voltage is induced by the rotatable permanent magnet means, with the at least one of the amplitudes and at least one of the phases of the relative geometrical position of the at least one additional coil arrangement and the permanent magnet being used as a sensor signal for stabilizing the magnetic bearing.

Abstract: A vacuum pump system for multi-stage gas inlet systems and including a pumping unit formed of a turbomolecular pump and one or several further pumps arranged downstream of the turbomolecular pump and the rotors of which are located on the same shaft as the rotor of the turbomolecular pump, and an additional intermittently operated dry running pump, which discharges against atmospheric pressure.

Abstract: A method of cooling rotor elements of a molecular vacuum pump having stator and rotor elements, a suction flange defining a gas inlet, and a gas outlet spaced from the suction flange, the method including providing additional gas inlet between the suction flange and the gas outlet and admitting through the additional gas inlet a cooling gas having a thermal conductivity larger than that of the compressible gas.

Abstract: A friction pump having individual components designed to form simultaneously essential parts of a magnetic bearing assembly for supporting the pump rotor, and essential parts adapted to fulfill essential functions of a friction pump.