Abstract: The invention relates to a vibratory limit switch configuration and to a process for operating such a configuration, with a fork (2); a transmitting and/or receiving device (3) for generating a vibration (w(fr)) for the fork as dependent on an exciter signal, and for receiving a vibration from the fork and for generating a reception signal (e) as dependent on the received vibration; and a control device (4) for providing the exciter signal and/or for processing the reception signal, where a device (8, 8*) is provided for detecting the temperature (T) of the fork or the temperature (T) of a space adjacent to the fork.

Abstract: The invention pertains to a level measuring by an apparatus has oscillating fork (1) that is excited to oscillate by an oscillator circuit that, for example, is realized in the form of a series circuit consisting of an input amplifier (2), a band filter (3) and an output amplifier (4). An identifying element (6) is assigned to the oscillating fork (1), with the identifying element transmitting the fundamental frequency of the oscillating fork (1) to the oscillator circuit (2, 3, 4) in coded form. In addition, the identifying element (6) transmits the fundamental frequency of the oscillating fork (1) to the control input of a frequency evaluation circuit (5), the input of which is connected to the output of the oscillator circuit (2, 3, 4). Consequently, the parameters of the band filter (3), as well as of the frequency evaluation circuit (5), are optimally adjusted to the fundamental frequency of the oscillating fork (1).

Abstract: A method for controlling a transducer device (7) featuring supply lines (17, 18) in a level sensor. The transducer device (7) is coupled to a fork resonator with fork tines and is used for both oscillation excitation and also for oscillation detection. For detection of a defective transducer device or an incorrectly connected connection of this transducer device (7), the capacitance value between the supply lines (17,18) or a variable proportional to this value is determined during the oscillation excitation and if there is deviation from a predetermined desired value by a predetermined amount, a fault signal is generated.

Abstract: An oscillating element, particularly for a level sensor, comprises an oscillating diaphragm (3), a stack of piezoelectric elements (6, 7), and a tie bolt (4) connected to the diaphragm (3) for pressing the piezoelectric elements (6, 7) against the diaphragm (3). The tie bolt (4) forms a single piece with the diaphragm (3).

Abstract: The invention pertains to a method for controlling a transducer device (7) featuring supply lines (17, 18) in a level sensor. The transducer device (7) is coupled to a fork resonator with fork tines and is used for both oscillation excitation and also for oscillation detection. For detection of a defective transducer device or an incorrectly connected connection of this transducer device (7), the capacitance value between the supply lines (17, 18) or a variable proportional to this value is determined during the oscillation excitation and if there is deviation from a predetermined desired value by a predetermined amount, a fault signal is generated.

Abstract: A method for controlling piezoelectric drives in filling level measuring devices, in the case of which a piezoelectric device (7) is coupled to a fork resonator, and this piezoelectric device (7) is used to excite and detect vibrations. The excitation signal (B) is an at least approximately trapezoidal signal, as a result of which the generation of undesired harmonic resonances in the fork resonator can be effectively avoided. The excitation signal preferably comprises two phases with approximately constant maximum and minimum levels, respectively, which are interrupted in each case by a phase of defined period and defined limited rate of signal change.

Abstract: A method for controlling piezoelectric drives in filling level measuring devices, in the case of which a piezoelectric device (7) is coupled to a fork resonator, and this piezoelectric device (7) is used to excite and detect vibrations. The excitation signal (B) is an at least approximately trapezoidal signal, as a result of which the generation of undesired harmonic resonances in the fork resonator can be effectively avoided. The excitation signal preferably comprises two phases with approximately constant maximum and minimum levels, respectively, which are interrupted in each case by a phase of defined period and defined limited rate of signal change.

Abstract: The invention pertains to level measuring by means of an oscillating fork (1) that is excited to oscillate by an oscillator circuit that, for example, is realized in the form of a series circuit consisting of an input amplifier (2), a band filter (3) and an output amplifier (4). An identifying element (6) is assigned to the oscillating fork (1), with the identifying element transmitting the fundamental frequency of the oscillating fork (1) to the oscillator circuit (2, 3, 4) in coded form. In addition, the identifying element (6) transmits the fundamental frequency of the oscillating fork (1) to the control input of a frequency evaluation circuit (5), the input of which is connected to the output of the oscillator circuit (2, 3, 4). Consequently, the parameters of the band filter (3), as well as of the frequency evaluation circuit (5), are optimally adjusted to the fundamental frequency of the oscillating fork (1).

Abstract: A method for controlling piezoelectric drives in filling level measuring devices, in the case of which a piezoelectric device (7) is coupled to a fork resonator, and this piezoelectric device (7) is used to excite and detect vibrations. The excitation signal (B) is an at least approximately trapezoidal signal, as a result of which the generation of undesired harmonic resonances in the fork resonator can be effectively avoided. The excitation signal preferably comprises two phases with approximately constant maximum and minimum levels, respectively, which are interrupted in each case by a phase of defined period and defined limited rate of signal change.

Abstract: An oscillating element, particularly for a level sensor, comprises an oscillating diaphragm (3), a stack of piezoelectric elements (6, 7), and a tie bolt (4) connected to the diaphragm (3) for pressing the piezoelectric elements (6, 7) against the diaphragm (3). The tie bolt (4) forms a single piece with the diaphragm (3).