Abstract: A friction vacuum pump (1) with a frame (5), stator (3), rotor (4) and housing; all functional elements of the pump are combined into one unit (22), which, in turn, can be inserted into a housing (19, 55) that has been adapted to a specific application; using this procedure, all separate connection housing can be eliminated and optimal conductance can be achieved (FIG. 1).

Abstract: The invention relates to a friction vacuum pump (1) with a stator (3) and a rotor (4), which form at least two pump stages (12, 13, 14) with one gas inlet (23, 28) each, as well as with junction for the pump stages, which are equipped with junction openings (36,37) and serve for the connection of the gas inlets (23, 28) of the pump stages with devices to be evacuated; in order to avoid high conductance losses it is proposed that the junction openings (36, 37) are located in a plane which is disposed laterally adjacent to the pump stages (12, 13, 14) such that the distance between the junction openings (36, 37) and the rotor axis (15) is of minimum feasible size.

Abstract: The invention relates to a friction vacuum pump (1) containing at least one turbomolecular pump stage (6, 7), a screw pump stage (11, 12) connected to the delivery side of the pump, and a filling stage (24) arranged between the turbomolecular pump stage (6, 7) and the screw pump stage (11, 12). According to the invention it is proposed that said filling stage (24) be configured as a centrifugal stage in order to simplify the construction thereof.

Abstract: Method for operating, a helium leak indicator (1) consisting of a helium detector (4) with evacuation devices comprising at least a high-vacuum pump (6), a backing pump (9) and a valve (16) whose level of flow conductance can be adjusted and serves to modulate the through-flow of test gas to be analyzed; in order to influence the sensitivity in a simple manner, the method provides that the modulation properties be changeable in such a manner that the effective pumping capacity at the inlet of the leak indicator is changed by the adjustment of the modulation properties.

Abstract: A screw vacuum pump (1) has rotors (5), bearings (7, 8), a casing (4), a suction side (15), and a delivery side (24). Each of the rotors includes at least two rotor sections, a suction side rotor section (17) and a delivery side rotor section (18). The two rotor sections are separately constructed and joined together in a positive, form-fitting or friction locking manner. The suction side rotor section is preferably larger in diameter and constructed with looser tolerances as compared to the delivery side rotor section. The suction side rotor is preferably of an inexpensive material such as aluminum while the discharge side rotor is preferably constructed of a higher performance material such as stainless steel. The rotor sections are supported on a rotor shaft (6) into which cooling fluid is injected through a cooling pipe (33). Cooling fluid from the shaft is also circulated through the bearings and passages in the casing eventually reaching a sump (37) in preparation for recirculation.

Abstract: A process is disclosed for testing the tightness of a package (11) containing a packaged object (10) and in which a test gas is contained; leak testing is performed in such a manner that the packaged object (10) is introduced into a test chamber formed by two extensible foils (2, 3) and where the space between the foils (2, 3), in which the packaged object is contained, is evacuated in such a manner that the foils (2, 3) can wrap the packaged object (10); at least in the areas of their surfaces which face the packaged object (10) and in which the tightness of the package (11) is to be inspected, the foils (2, 3) are provided with means (12) which form a coherent intermediate space (13) over the areas to be inspected of the package (11); the intermediate space (13) is evacuated down to a pressure lower than the pressure within the package (11); the evacuated intermediate space (13) is connected to a detector (30) sensitive to the test gas to determine if test gas escapes outwards through the inspected area of

Abstract: The invention relates to a Penning vacuum meter (1), comprising a cathode and an anode. According to the invention, the cathode (11) consists at least mainly of titanium in order to avoid the detrimental effects of the cathode disintegrating.

Abstract: A gas passage (1) with a selectively acting penetration surface consisting of quartz, quartz glass, Pyrex glass or the like; in order to provide penetration surfaces which are relatively thin on the one hand but will withstand relatively great pressure differences on the other, it is proposed that the selectively acting penetration surface take the form of a plurality of adjacent windows (5).

Abstract: The invention relates to a multistage low-temperature refrigeration machine with a first stage in the form of a displacer refrigerator (1) as well as at least one further stage in the form of a pulse tube refrigerator (25); in order to suppress vibrations it is proposed that a flexible component (45) designed to prevent the spread of vibrations be placed between the displacer refrigerator (1) and the pulse tube refrigerator (25).

Abstract: The present invention relates to a friction vacuum pump having at least one turbomolecular pump stage (2) joined at its pressure side to a screw pump stage (4). In order to improve the pump properties it is proposed that a filling stage (3) be arranged between the turbomolecular pump stage (2) and the screw pump stage (4) that has blades (13) whose length corresponds at the suction side to the active length of the blades at the pressure side of the turbomolecular pump stage (2), and at the pressure side to the depth of the suction-side region of the screw (14) of the screw stage (4).

Abstract: The invention concerns an oil-sealed vane-type rotary vacuum pump (1) with a rotor (3) and an oil pump (45, 46) whose suction chamber is fitted with feeds (64, 65) for gas and oil. In order to simplify the supply of a gas/oil mixture to the vacuum pump, the invention proposes that the gas and oil feeds (64, 65) are disposed in such a way that initially only oil and subsequently both oil and air are aspirated into the volume swept by the oil pump (45, 46) as it rotates.

Abstract: A vacuum pump has a shaft bearing (6) supported in a bearing outer ring (8). In order to improve the damping properties a substantially cylindrical radial supporting ring (7) is provided between the outer ring (8) and an interior surface of a bore (9) in a housing (1). First and second circumferential projections (11, 12) project from opposite edges of cylindrical ring (7) on one side. On its other side, a third circumferential projection (13) is axially arranged between the first projections (11, 12). The first and second projections engage one of the outer race and the bore and the third projection engages the other. The damping of the radial support ring (7) is determined by its radial stiffness which is determined by the stiffness of the material and the distance between the projections (11, 12, 13).

Abstract: A vacuum pump, comprising at least one pump chamber (7, 8, 23 to 26) and at least one chamber (3, 5, 27) adjoining the pump chamber. The vacuum pump is fitted with a gas ballast device to avoid damage being caused in the adjoining chambers by the gases being pumped, the ballast gas being delivered via the chamber adjoining the pump chamber.

Abstract: A helium supply unit (1) supplies helium from a high pressure storage (21) to fill a test chamber (6) which encloses a sample holder (5) to be examined for leaks by measuring device (2) including a mass spectrometer (3) and a control unit (4). The test gas is recovered after the testing by a pressure difference between a low pressure storage (18) and the test chamber (6). The test chamber is evacuated prior to receipt of the test gas by a vacuum pump (27) and after testing by a vacuum pump (34) for more complete helium recovery. The recovered test gas is then transmitted back to the high pressure storage (21) through a compressor (19), which raises the pressure of the recovered gas to a predetermined pressure, from the low pressure storage (18). The control unit (4) also controls a pure test gas supply (37) and a release valve (44).

Abstract: The invention relates to a cryopump having pump surfaces which are held at different temperatures during operation and are disposed in a housing with a flange for connecting the housing to a vacuum chamber. Additional pump surfaces are provided for the accumulation of easily condensable gases and improve the suction performance of the cryopump. These additional pump surfaces are disposed in the vacuum chamber and are connected to a first stage of a two stage refrigeration head via a cold bridge.

Abstract: The invention relates to a low-temperature refrigerator (1) for producing temperatures in a defined low-temperature range, with a cold head (3) which is fitted with a regenerator (6).sup.6) and in which a thermodynamic circulation process (regenerative cold generation process) is carried out to generate cold. To reduce the technical complexity of the cold generation process, it is proposed that the cold head (3) should be a single-stage unit and the physical characteristics of the regenerator (6).sup.7) in the cold machine (1) should be so selected as to ensure that the cold head (3).sup.8) has an optimal cold output in the desired temperature range. (drawing FIG. 2).sup.6) Translator's note: The German text states "7" here whereas "6" would be more in line with the remaining text and the drawing figures. Therefore "6" has been assumed for the translation..sup.7) Translator's note: The German text states "7" here whereas "6" would be more in line with the remaining text and the drawing figures.

Abstract: The invention concerns a friction vacuum pump (1) with an inlet (11), an outlet (20) and a rotor (6, 7) and stator (14, 21) which are located between the inlet (11) and the outlet (20) and carry blades (7 and 8), respectively. In order to design an intermediate inlet (28), which passes into an annular channel (31) surrounding the stator and rotor blades (7 and 8), respectively, so that it is simple and effective, the invention proposes that the stator (21) consists of annular blades or blade segments (25) and annular spacers (22, 23, 24), the outer edges (26) of the annular blades or blade segments (25) being located between the spacers (22, 23, 24) and at least one spacer (23, 24) located at the height of the annular channel (31) having perforations (32) in it.

Abstract: A process is disclosed for inspecting a plurality of similar test bodies for leaks. The test bodies are first evacuated by a fore-vacuum vacuum pump (evacuation mode), down to a pressure P.sub.u, selected to ensure that the maximum admissible pressure in the mass spectrometer (5) is not exceeded when the measurement mode is switched on, and then the evacuation mode is switched to a measurement mode by opening the second valve (16). In order to shorten evacuation times, a learning process is used to determine the optimum switching pressure P.sub.u opt.

Abstract: The invention concerns an oil-sealed vane-type rotary vacuum pump with a suction chamber (8) housing a rotatably mounted rotor (3) which has an anchoring section (21) and a bearing section (23) with a slot (24) in which two vanes (26) are mounted with a space (28) between them. The rotor bearing (3) comprises the bearing section (23) and a rotor-mounting bore (11). The vacuum pump also has an oil pump (45, 46), which produces a flow of oil through the space (28) between the vanes, and a system for controlling the flow of oil through the space (28), the oil passing through a channel (66) opening out in the rotor-mounting bore (11) and then through radial and longitudinal bores (68, 69) in the bearing section (23) of the rotor.

Abstract: A refrigerator for cryogenic pumps, cryostats and the like, includes a housing having a cylindrical working volume inside the housing and a displacement element capable of moving in a reciprocal manner within the working volume. The displacement element is driven by a gas drive. To reduce vibrations, the displacement element is forcibly guided.