Abstract: The leak detection appliance has a test inlet to which a test chamber containing the test specimen can be connected. A high-vacuum pump produces a high vacuum in a test gas detector. A backing pump contains two pump stages. In order to evacuate the test chamber, the pump stages are operated in parallel mode, with their suction capabilities being added. When the necessary vacuum has been achieved, the pump stages are operated in series in order to produce the necessary high vacuum which is required for high detection sensitivity on the test gas detector.

Abstract: A sniffing leak detector comprises a handle with a sniffing tip. Located at the sniffing tip is a measurement gas suction opening and a reference gas suction opening. The reference gas suction opening is intended for suctioning ambient gas. The reference gas suction opening is aligned substantially the same as the measurement gas suction opening such that both suction openings are sensitive in the same direction.

Abstract: The leak detection appliance has a test inlet to which a test chamber containing the test specimen can be connected. A high-vacuum pump produces a high vacuum in a test gas detector. A preliminary vacuum pump contains two pump stages. In order to evacuate the test chamber, the pump stages are operated in parallel mode, with their suction capabilities being added. When the necessary vacuum has been achieved, the pump stages are operated in series in order to produce the necessary high vacuum—which is required for high detection sensitivity—on the test gas detector.

Abstract: A sniffing leak detector comprises a handle with a sniffing tip. Located at the sniffing tip is a measurement gas suction opening and a reference gas suction opening. The reference gas suction opening is intended for suctioning ambient gas. The reference gas suction opening is aligned substantially the same as the measurement gas suction opening such that both suction openings are sensitive in the same direction.

Abstract: A fuel injector (1) for the direct injection of fuel into the combustion chamber of an internal combustion engine has a piezoelectric actuator (2) which is encapsulated in an actuator housing (3); a valve needle (9) which is in operative connection with the actuator and on which a valve-closure member (11) is formed which forms a sealing seat together with a valve-seat surface (13); and a nozzle body (12) into which the actuator housing (3) is able to be inserted. The actuator housing (3) and the nozzle body (12) are sealed by a common connecting part (4), the connecting part (4) having a first and a second diameter step (19; 20).

Abstract: A fuel injector (1) for the direct injection of fuel into the combustion chamber of an internal combustion engine has a piezoelectric actuator (2) which is encapsulated in an actuator housing (3); a valve needle (9) which is in operative connection with the actuator and on which a valve-closure member (11) is formed which forms a sealing seat together with a valve-seat surface (13); and a nozzle body (12) into which the actuator housing (3) is able to be inserted. The actuator housing (3) and the nozzle body (12) are sealed by a common connecting part (4), the connecting part (4) having a first and a second diameter step (19; 20).

Abstract: The invention relates to an infrared gas analyser (1), especially for use as a gas detector for leak detection using a sampling probe. Said gas analyser comprises a vessel (test vessel 2), through which a test gas flows, and an infrared light source (4, 5, 42) which produces an infrared light that shines through the test vessel (2). The analyser further encompasses a detector (35) that facilitates measurement of the infrared light absorption in the test gas. The aim of the invention is to provide at low costs an analyser that is apt for every day use. To this end, a reference vessel (3) through which a reference gas flows is provided in addition to the test vessel (2) through which the test gas flows. A reference gas is sucked from the environment of the test gas suction area. The same or an additional light source (4, 5, 42) and the same detector (35) are allocated to said reference vessel.

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 process for operating a test gas leak indicator (1) with a gas inlet (2) and a test gas-sensitive detector (4), in which all or part of a stream of gas containing the test gas reaching the inlet (2) is taken to the detector (4) in the event of a leak; in order to improve the sensitivity of the leakage detection, it is proposed that the stream of gas be preferably periodically modulated and the signal from the test gas detector (4) be processed in synchronism with the modulation of the gas flow.

Abstract: A leak detector (1) suitable for detecting leakage with a test gas connection (2), a test gas detector (3), a gas pump (4) and a test gas line (5) extending between the test gas connection (2) and the gas pump (4) and connected to the inlet (6) of the test gas detector (3) via a blockable branch; in order to shorten the response time, it is proposed that the line (7, 8) connecting the test gas line (5) to the inlet region (6) of the test gas detector be such that, during measurement, all of the gas flowing in the test gas line (5) essentially enters the inlet region (6) of the test gas detector (3).

Abstract: The invention relates to a test gas detector, preferably for leak detection instruments, with a selective, preferably test-gas-permeable inlet system (6) and with a device (5) recording the presence of test gas; to reduce the complexity in the production of the vacuum it is proposed that the test gas recorder (5) comprise a gas consuming vacuum gauge (8).

Abstract: A simple, compact and reliable quadrupole mass spectrometer head gauge is shown in which an ion source and flange are mounted on one end of a one-piece quadrupole separating system and a detector is mounted on the other end with the flange end being adapted to be connected to a vacuum chamber.

Abstract: A system is disclosed for controlling vehicles equipped with computer systems from a center of a rapid transit system. If at least two vehicles equipped with computer systems form a train, and the computer system of the vehicle controlling the train fails, the control of the train can be shifted onto the computer system of another vehicle. Therefore, the individual on-board computers need not be fully redundant.

Abstract: The specification discloses a system for protected data transmission between a control center and a plurality of track-bound vehicles. The data is not acknowledged as correct until it is contained in two successive data messages which are compared. The comparison indicates whether the difference between the two successive messages is within predetermined limits.

Abstract: The system includes equipments necessary for demand registration and control organized hierarchically. The uppermost hierarchy level includes an operations control center and station equipment connected to the operations control center. The operations control center indicates the operation necessary at the next hierarchy level in accordance with the demand registered in the station equipment. The next hierarchy level includes one or more command and control centers. Each command and control center checks the commands of the operations control center and/or of the associated station equipment, giving special consideration to safety criteria, and passes on the commands to the last hierarchy level for execution. The last hierarchy level includes operation facilities, such as vehicles, which perform the requested transport tasks, continuously exchanging information with their associated command and control center.