Abstract: An arrangement for signal processing in ultrasonic transducers in flow meters has an ultrasonic transducer acted upon by a drive signal with the ultrasonic transducer being connected to a resonant circuit matched to the frequency of the drive signal. The resonant circuit can be a component of the network which makes switching over the ultrasonic transducer for transmitting operation to a receiving operation possible. An ultrasonic flow meter uses time-of-flight principle for transmitting and receiving ultrasonic signals and signal post-processing of the received ultrasonic signals. To make available an ultrasonic flow meter that produces an improved quality voltage signal for evaluation and at the same time makes possible a reduction of its production costs, a ringing circuit is provided. The ringing circuit may be a series ringing circuit for signal post-processing of the received ultrasonic signals connected to a comparator and using an LC-circuit, a Pi-filter or an RLC-circuit.

Abstract: The invention relates to an arrangement for signal processing in ultrasonic transducers in flow meters, wherein the ultrasonic transducer is acted upon by a drive signal, the ultrasonic transducer being connected to a resonant circuit matched to the frequency of the drive signal. The resonant circuit can be, in particular, a component of a network, which makes possible a switching over of an ultrasonic transducer from a transmitting operation to a receiving operation. The present invention further relates to an ultrasonic flow meter according to the time-of-flight principle, with means for transmitting and receiving ultrasonic signals as well as means for signal post-processing of the received ultrasonic signals.

Abstract: A gas thermometer has a case with a case end section (10) made of metal of good thermal conductivity and a main case section (14) made of material of poor thermal conductivity. By means of separating walls (46, 48, 62, 64, 70) and reflector walls (66, 68), two sound paths are created in the interior of the thermometer case, which differ by twice the distance between the reflector walls (66, 68). The phase difference of partial sound wave fields which are obtained by splitting a sound wave field produced by a common sound generator (40) between the two paths is converted to an electrical signal corresponding to the temperature in the case end section (10) by using microphones (26, 28) and an analyzing circuit (92) connected with them.

Abstract: An electronic thermometer has an oscillator, the frequency determining element of which is a temperature sensitive piezoelectric element (2), used as a measuring sensor, which is located inside a sealed housing (3). The piezoelectric element is provided with two termial electrodes (4, 5) which are galvanically separated from the oscillator circuit bia an inductively coupled pair of coils (6, 7); the coil (6) connected to the terminal electrodes is tightly encompassed by the housing. An evaluation unit (10) for detecting the temperature is connected to the oscillator circuit.

Abstract: An electronic thermometer has an oscillator, the frequency determining element of which is a temperature sensitive piezoelectric element, used as a measuring sensor, which is located in a sealed housing of electrically insulating material. The piezoelectric element is provided with two terminal electrodes, which are each connected via a respective capacitor to the oscillator circuit, and each of the two capacitors has electrodes, one located inside and one located outside the housing.