Abstract: A process for measuring the level of a liquid in a tank according to the radar principle, in which microwave energy is transmitted in the direction of the liquid level and the bottom of the tank from an antenna located above the liquid level, a measuring signal reflected from the liquid level is received by an antenna, and the liquid level may be determined from the transit time of the measuring signal, other signals than the measuring signals, i.e.

Abstract: A mass flow meter for flowing media which works on the Coriolis Principle includes a straight measuring pipe carrying the flow medium, an oscillator acting on the measuring pipe and two transducers detecting Coriolis forces and/or Coriolis oscillations based on Coriolis forces. The meter also has a carrier pipe holding the measuring pipe, the oscillator and the transducers and two temperature sensors that detect the temperature of the measuring pipe and correct the measured value depending on the temperature of the measuring pipe. The measuring pipe and the carrier pipe are connected to one another in a way that excludes relative axial movements, and the axial distance between the connecting points of the measuring pipe carrier pipe represents the oscillation length of the measuring pipe.

Abstract: An electrical device for measuring the liquid level in industrial tanks and the like with a microwave transmitter and receiver and a waveguide provided with an aperture and an antenna. The signal reflected from the liquid surface and the transmitted signal are fed to a frequency conversion stage (8), whose low-frequency output signal is sent via an A/D converter (12) to a microprocessor calculating the fill level. To reduce the effect of interference frequencies produced by reflection of microwaves in the optical aperture, etc., a band-pass filter (9,10) with a lower limiting frequency selected to attenuate the low-frequency interference frequencies is placed between the frequency conversion stage (8) and the A/D converter (12). The lower limiting frequency can either be controlled with microprocessor (13) or the band-pass filter (9, 10) has adjustable limiting frequencies.

Abstract: A distance measuring device for measuring the fill level in industrial tanks, which includes electronic transmitting- and receiving elements for short wave electromagnetic waves, such as microwaves, and a cylindrical waveguide which extends through a separating wall and inside of which is a waveguide window separating the two spaces and made of a material, such as quartz glass, which is transmissive with respect to electromagnetic waves. The waveguide and the waveguide window (3) have conically-shaped sections (5) to provide axial support. To protect the waveguide window against destruction due to thermal expansions and pressure fluctuations, the conical section (5) of the waveguide window (3) is in a correspondingly formed conical socket (8). The socket is mounted with play in a cylindrical bore (9) of the waveguide window (3) and is supported by a shoulder (10) of the waveguide in the axial direction.

Abstract: The light gate serving for the generation of a signal upon an undesired intrusion into the working space of a machine has a light source (1) whose light beams are successively directed via a controlled light-distribution unit to several optical channels (6) to which a light-receiving device is assigned. The light-distribution unit is provided with a number of directive optical couplers (3), corresponding to the number of optical channels (6) whose respective secondary waveguide adjoins a light conductor (4) of the associated optical channel (6) and which are connected via a further light conductor (2) in series with the light source (1) and with one another. The electrodes of the directive couplers (3) are connected to an electronic control and evaluation device (9). The directive optical couplers form electronically controllable light-switching points with whose aid the light pulses of the light source (1) can be successively and cyclically directed into the optical channels (6).