Abstract: A leak detector operating according to the counterflow principle comprises a first high vacuum pump that operates in series with a primary pump. A second high vacuum pump is branched at a connecting point and an entry side thereof is connected to a mass spectrometer. A light test gas in the form of helium flows through the second high vacuum pump in a direction opposite to a transport direction. A conduit connecting an inlet to the entry side of the first high vacuum pump is devoid of restricted flow zones and valves in such a way that the pumping capacity of the leak detector is high for helium, thereby reducing the response time thereof. A valve for blocking the conduit leading via the first high vacuum pump is arranged between the exit side thereof and the entry side of the primary pump.

Abstract: A leak detector operating according to the counterflow principle comprises a first high vacuum pump that operates in series with a primary pump. A second high vacuum pump is branched at a connecting point and an entry side thereof is connected to a mass spectrometer. A light test gas in the form of helium flows through the second high vacuum pump in a direction opposite to a transport direction. A conduit connecting an inlet to the entry side of the first high vacuum pump is devoid of restricted flow zones and valves in such a way that the pumping capacity of the leak detector is high for helium, thereby reducing the response time thereof. A valve for blocking the conduit leading via the first high vacuum pump is arranged between the exit side thereof and the entry side of the primary pump.

Abstract: A test gas leakage detector includes an inlet for gases to be analyzed for the presence of a test gas, a test gas detector and a first high vacuum pump connected to the test gas detector. An intermediate inlet is arranged on the first high vacuum pump that is used to supply the gases to be analyzed for the presence of a test gas. A fore-vacuum pump is connected to the first high vacuum pump and a line section fitted with a valve is located between the inlet and the fore-vacuum pump. In order to provide greater sensitivity and a quicker result time, a second high vacuum pump is provided between the inlet and the intermediate inlet. The second high vacuum pump has an outlet which is connected to the inlet of the fore-vacuum pump by means of a line section fitted with a valve.

Abstract: A method for detecting a test gas present at a measuring location, using an infrared gas analyzer having a cuvette, an infrared light source, an infrared detector, and two gas lines. A first gas line is adapted to take up a measuring gas at a measuring location that may contain a test gas to the cuvette. The second gas line is adapted to take up gas from the surroundings of the measuring location (i.e., reference gas), that may contain a test gas background that is to be taken into consideration when detecting the test gas taken up at the measuring location. To improve the sensitivity of the analyzer, only one cuvette and the measuring gas is taken up at the measuring location and the reference gas is fed to the cuvette such that each gas is alternately present therein.

Abstract: The invention relates to a test gas leakage detector (1), comprising an inlet (2) for gases to be analyzed for the presence of a test gas, a test gas detector (22), a high vacuum pump system (15) connected to the test gas detector, an intermediate inlet (14) arranged on the high vacuum pump system (15) and used to supply the gases to be analyzed for the presence of a test gas, a fore-vacuum pump (8) connected to high vacuum pump system (15) and a line section (3, 6) fitted with a valve (5) and located between the inlet (2) and the fore-vacuum pump (8). In order to provide a device of the above-mentioned category which is quicker and more sensitive, another high vacuum pump (11) is provided between the inlet (2) and the intermediate inlet (14), having an outlet (12) which is connected to the inlet (7) of the fore-vacuum pump (8) by means of a line section fitted with a valve (17).

Abstract: The invention relates to a method for detecting a test gas that may be present at a measuring location, using an infrared gas analyser (1) that comprises a cuvette (2), an infrared light source (3), an infrared detector (4), and two gas lines (15, 17). Said gas lines supply gases to the infrared gas analyser and one of said lines is adapted to take up a measuring gas at a measuring location that may contain a test gas. The second line (17) is adapted to take up gas from the surroundings of the measuring location (reference gas), which gas may contain a test gas background that is to be taken into consideration when detecting the test gas taken up at the measuring location. In order to improve the sensitivity of the analyser it comprises only one cuvette (2) and the measuring gas taken up at the measuring location and the reference gas are fed to the cuvette of the infrared gas analyser in such a manner that they are alternately present in the cuvette.

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.