Abstract: The invention relates to an electromechanical drive or a sensor element composed of piezoelectric elements arranged in the form of a stack. The drive or the sensor element is intended for measurement instruments and operates even at very high temperatures. The new drive or the new sensor element (10) for this purpose comprises a number of piezoelectric ceramic layers (12a-f), with electrode layers (16a-e) in each case being arranged between two mutually facing surfaces of directly adjacent piezoelectric ceramic layers. Connectors (18a,b) in the form of wires run in grooves (14a-d) in the electrode layers (16a-e) in order to make electrical contact with the electrode layers (16a-e), and are passed out of the electrode layers (16a-e).

Abstract: The invention relates to a filling level measuring device which is used to measure the level of a filling material in a container. A probe is provided, which protrudes inside the container. The filling level measuring device can be mounted and dismounted without the probe needing to be moved in the container. The inventive device comprises a housing consisting of a first section, and a second section, the sections respectively comprising a central axial bore whereby the first section has an interior diameter which is smaller than that of the second section. A securing device is provided on the housing for securing the filling level measuring device onto the container. An insert is disposed in the housing in such a way so that it can pivot in relation to the housing, the insert being placed on a surface between the first and the second sections.

Abstract: A description is given of a filling level measuring device operating with microwaves, having a housing and an insert composed of a dielectric, and of a process for producing the dielectric, in which the dielectric constant of the insert is adjustable and in which the insert has a high chemical resistance and a mechanical strength adequate for industrial applications. The dielectric is a composite material composed of a fluoroplastic, in particular polytetrafluoroethylene, and ceramic and is produced by mixing powdered ceramic and powdered fluoroplastic, drying the mixture, pressing the mixture and sintering the pressed mixture.

Abstract: The invention relates to a device for determining the filling level of a filling material in a container. The device has a signal-generating unit, which generates electromagnetic measuring signals, a transceiver unit, which emits the measuring signals via an antenna in the direction of the surface of the filling material and which receives the echo signals reflected at the surface of the filling material, the antenna comprising a waveguide which widens in the direction of emission into a cavity of a defined shape, and an evaluation unit which determines the filling level in the container from the propagation time of the measuring signals. At least one dielectric filling material is provided which at least partially fills up the waveguide, and which virtually completely fills up the widened cavity of the antenna.

Abstract: The active brazing solder for brazing ceramic parts of alumina, particularly of high-purity alumina, contains a maximum of 12 wt. % Ti, a maximum of 8 wt. % Be, and less than 16.5 wt. % Fe, the remainder being Zr and any impurities that may be present. The active brazing solder has the following behaviour/features: Brazing temperature: lower than 1,000° C.; the brazed joint is high-vacuum-tight over a long period of time; the coefficient of thermal expansion of the active brazing alloy is substantially identical to that of the alumina ceramic in the entire temperature range covered during the brazing process; the strength of the brazed joint between the two ceramic parts is so high that under tensile loading, fracture will result not at the joint, but in the adjacent ceramic; the pressure resistance of the active brazing solder is greater than 2 GPa; the active brazing solder is very good processable into powders having particle sizes on the order of 10 &mgr;m.

Abstract: A method for shortening a cable, which is mounted in a device housing of a measurement device, of a cable probe, comprising the step of: removing the measurement device electronics; interrupting the electrical connections between the measurement device electronics and the cable probe; releasing a built-in sleeve which surrounds the cable, as a result of which at least one seal which surrounds the cable and acts with respect to a medium to be measured, is relieved of load; drawing out of the device housing the built-in sleeve, together with the cable and the seal; shortening the cable by a desired length; once again drawing over the remaining cable of the cable probe, a seal, a built-in sleeve and clamping cone and mounting the cable in the built-in sleeve, by pulling it into said built-in sleeve; once again making the electrical connections between the cable probe and the measurement device electronics; and once again closing the device housing once the measurement device electronics have been fitted.

Abstract: In a method of transmitting a measurement signal M between a measuring unit 1 and a control unit 10, the uniform measurement signal has a supplementary signal Z superimposed on it which alternates over time. To check the operation of the measuring unit 1, the measurement signal M is evaluated in the control unit 10. If the supplementary signal Z is erroneous, the control unit 10 produces an alarm signal.

Abstract: The microwave measuring device, which preferably operates with microwave bursts, serves to produce a measured value (XH) representing the level of the contents of a vessel (200). It comprises a transceiver unit (2) for generating a level-dependent intermediate-frequency signal (ZF) by means of a transmit signal (S2) and a receive signal (E2), and a transducer element (1) which in operation couples waves (S1), particularly pulsed waves, into the vessel under control of the transmit signal (S2) and converts echo waves (E1) reflected from the contents (201) of the vessel into the receive signal (E2). The intermediate-frequency signal (ZF) is fed to a control unit (3) of the level measuring device where it is stored in the form of a sampling sequence (AF) in a volatile data memory (33). In this manner, both amplitude information and phase information is available for the level measurement. The device is thus capable of measuring level with high accuracy, particularly accurately to a millimeter, and very fast.

Abstract: The invention relates to a device for emitting high-frequency signals, comprising a signal generation unit, a signaling line, an emission cable and an antenna configured as a circular waveguide, said antenna being sealed in an end section by a rear wall. According to the invention, the signal generation unit creates the high-frequency signals, the signaling line conducts the high-frequency signals along the emission cable and said emission cable projects into the interior of the antenna and is positioned approximately parallel to the rear wall. The invention aims to provide a device for emitting electromagnetic waves, which is characterized by optimized emission characteristics. To achieve this, the distance (Z) between the emission cable and the rear wall of the antenna is approximately &lgr;/6, whereby &lgr; is the wavelength of the high-frequency signals borne by the antenna.

Abstract: The invention relates to an electromechanical drive or a sensor element composed of piezoelectric elements arranged in the form of a stack. The drive or the sensor element is intended for measurement instruments and operates even at very high temperatures. The new drive or the new sensor element (10) for this purpose comprises a number of piezoelectric ceramic layers (12a-f), with electrode layers (16a-e) in each case being arranged between two mutually facing surfaces of directly adjacent piezoelectric ceramic layers. Connectors (18a,b) in the form of wires run in grooves (14a-d) in the electrode layers (16a-e) in order to make electrical contact with the electrode layers (16a-e), and are passed out of the electrode layers (16a-e).

Abstract: A pressure mediator includes a base body; a divider diaphragm system having a first divider diaphragm and a second divider diaphragm, between which an intermediate chamber is enclosed in pressuretight fashion, in which the first surface of the first divider diaphragm, remote from the intermediate chamber, can be acted upon by the pressure prevailing in the first medium, and the first surface of the second divider diaphragm, remote from the intermediate chamber, is oriented toward the base body and is secured by its peripheral region to the base body, forming a pressure chamber between the base body and the second divider diaphragm, and the pressure chamber can be filled with the second medium and has a pressure chamber opening, through which the pressure can be transmitted by means of the second medium, and an exertion of pressure of the first divider diaphragm can also be transmitted to the second divider diaphragm via the intermediate volume; and having a sensor, for monitoring a property of the intermediat

Abstract: A description is given of a measuring instrument to be connected to a higher-order unit (57, 75) having at least a first and an identical second pair of terminals, which can be connected electrically, very simply and without errors, to the higher-order unit, the measuring instrument (61) comprising: a first pair of lines (1), to be connected to the first pair of terminals, via which a signal current flows during operation, the signal current being a measure of an instantaneous measured value, and a second pair of lines (3), to be connected to the second pair of terminals, via which a supply current flows during operation, whose value is greater than or equal to a minimum signal current and less than or equal to a maximum signal current.

Abstract: An apparatus for determining the filling level of a product in a container with a transmission unit which generates high-frequency signals and emits them at a predetermined pulse repetition frequency in the direction of the surface of the filled product. The signals are reflected by the surface of the filled product and are received by a receiving unit. A delay circuit transforms the high-frequency signals/reflected signals into low-frequency signals in accordance with a predetermined translation factor and with an evaluation unit which determines the filling level of the product in the container on the basis of the delay time of the signals. The delay circuit includes: a transmission oscillator; a sampling oscillator; a digital sampling circuit; and a closed-loop/open-loop control unit.

Abstract: A cable bushing which is small, simple and cost-effective as possible, having a cable, a housing, though which the cable is led, and which has a radially inwardly extending step at its first end, a first sleeve, which engages around the cable and which has a first section arranged inside the housing. The first sleeve is held by the step in the housing, the first sleeve bearing in a seal-forming fashion against the cable and there being a sealing means between the step in the housing and the fist sleeve. A second sleeve is arranged in the interior of the housing and has a first cylindrical section which engages closely around the cable, the first sleeve having a second section which adjoins an end of the first section which faces the step, said second section bearing on the first section of the first sleeve, and an attachment element by means of which the second sleeve is pressed against the first sleeve.

Abstract: A chamber in the interior of a housing communicates with the environment of the housing by means of a gas esxchange path, wherein a filter element with a hydrophobic and/or hydrophobicized, nanoporous material is placed in the gas exchange path. The chamber serves, e.g. to accomodate electronic circuitry, or it is chamed as a reference pressure chamber of a relative pressure sensor. The relative pressure sensor according to the present invention for capturing a measured pressure with respect to a reference pressure comprises a reference pressure path 23 which extends between a surface which can be exposed to the reference pressure and an opening in a reference pressure chamber 22, a filter element 30 which is arranged in the reference pressure path comprising a hydrophobic or hydrophobicized, nanoporous material. The filter element allows pressure compensation on account of its permeability to N2 and O2, while water molecules are selectively blocked.

Abstract: The invention relates to an apparatus for determining the filling level of a filling material in a container having a signal production unit which produces measurement signals, having at least one antenna which transmits the measurement signals in the direction of the surface of the filling material and which receives the measurement signals reflected on the surface of the filling material, and having a control/evaluation unit which uses the delay time of the measurement signals to determine the filling level of the filling material in the container. The apparatus allows a filling level measurement device, which operates on the delay-time principle, to be mounted on a container in a cost-effective and simple manner.

Abstract: A pressure sensor element for mounting in a connecting element comprises an isolator body with a laterally projecting membrane. The laterally projecting membrane covering an opening of a passage through which the pressure present at the surface of the membrane is conveyed to a pressure transducer element by means of a hydraulic fluid. In order to mount the pressure sensor element, it is secured in a mounting aperture of the connecting element. The projecting perimeter of the membrane is secured to the surface surrounding the mounting aperture of the connecting element by means of a continuous seam. A membrane type ring in combination with a conventional membrane may be substituted for the projecting membrane, wherein the membrane type ring covers the gap between the pressure sensor element and the adapter element.

Abstract: A transmitter is provided whose operation is not impaired by ambient influences, having a measurement sensor (3), an electronic unit (11) arranged in a housing (1) on a printed circuit board (9), an operating element (15), which can be operated from outside the housing (1), and a transmitting arrangement (19), which transmits a force exerted on the operating element (15) to a switch connected to the electronic unit (11), the switch being a key of a membrane keyboard (23) arranged on the printed circuit board

Abstract: A device for determining and/or monitoring the level of a medium in a container or for ascertaining the density of a medium in the container embodied as a vibration detector. According to the invention the vibration detector still functions reliably even under extreme process conditions and upon abrupt changes in process conditions. The vibration detector has a tubular inner part provided, which is dimensioned such that it is positioned between the housing wall and a drive/receiving unit, and that the tubular inner part is connected to the housing or to the diaphragm.

Abstract: This invention relates to a level-measuring device in which a signal generating device, a sampling device and a transmitting and/or receiving device are optimally connected to one another for various applications and signal shapes. The signal generating device generates both a radio-frequency transmit signal and a sampling control signal for sampling the radio-frequency signal. The sampling device, the signal generating device and the transmitting and/or receiving device being connected by a coupling device which comprises one of: a transformer; at least one line node; a &lgr;/4 coupler and a circulator.