A device for determining and/or monitoring at least one process variable of a medium in a container includes four, rod-shaped elements arranged on a membrane, three piezoelectric elements and an electronics system, wherein one first and one second rod-shaped element are arranged and configured such that they form a mechanically vibratable unit, wherein the device is configured to excite the vibratable unit via an excitation signal to create mechanical oscillations, to receive the mechanical oscillations of the vibratable unit, to convert them into a first received signal, to transmit a transmitted signal, and to receive a second received signal, and wherein the electronics system is configured to determine the at least one process variable based on the first and/or second received signal.

A device for determining and/or monitoring at least one process variable of a medium in a container includes four, rod-shaped elements arranged on a membrane, three piezoelectric elements and an electronics system, wherein one first and one second rod-shaped element are arranged and configured such that they form a mechanically vibratable unit, wherein the device is configured to excite the vibratable unit via an excitation signal to create mechanical oscillations, to receive the mechanical oscillations of the vibratable unit, to convert them into a first received signal, to transmit a transmitted signal, and to receive a second received signal, and wherein the electronics system is configured to determine the at least one process variable based on the first and/or second received signal.

A device and a method for determining and/or monitoring at least one process variable of a medium include a sensor unit having a mechanically oscillatable unit, at least a first piezoelectric element, a temperature detection unit for determining and/or monitoring a temperature of the medium and an electronics unit. The device is embodied to excite the mechanically oscillatable unit by means of an excitation signal such that mechanical oscillations are executed, to receive mechanical oscillations of the oscillatable unit and convert them into a first received signal, to transmit a transmitted signal and to receive a second received signal. The electronics unit is embodied, based on the first and/or second received signal, to determine the at least one process variable and, based on a third received signal received from the temperature detection unit, to determine the temperature of the medium.

The invention provides a method of driving a vibrating sensor in which the drive signal is combined with an amplitude modulated high frequency carrier. The signal is demodulated at a position adjacent to the component to be driven. This method may be applied to reducing cross-talk between drive and pick-up wire pairs and also to passing both drive and pickup signals, and two drive signals, down the same wire pair.

The invention provides a method of driving a vibrating sensor in which the drive signal is combined with an amplitude modulated high frequency carrier. The signal is demodulated at a position adjacent to the component to be driven. This method may be applied to reducing cross-talk between drive and pick-up wire pairs and also to passing both drive and pickup signals, and two drive signals, down the same wire pair.

A multi-path acoustic signal apparatus, system, and apparatus for use in material detection are provided. The apparatus has a plurality of acoustic sensors positioned along a first portion of a fluid container. At least one acoustic signal is transmitted into the fluid container by each of the plurality of acoustic sensors. At least one additional acoustic sensor is positioned along a second portion of the fluid container, wherein the second portion is substantially opposite the first portion. The at least one additional acoustic sensor receives at least a portion of the acoustic signals from the plurality of acoustic sensors. A reflected acoustic signal is generated from an impedance barrier between the fluid container and a fluid therein. A characteristic of a material of the fluid container and/or the fluid therein are determined.

A device and a method for determining and/or monitoring at least one process variable of a medium include a sensor unit having a mechanically oscillatable unit, at least a first piezoelectric element, a conductivity/capacitance detecting unit for determining and/or monitoring a conductivity and/or capacitance of the medium and an electronics unit. The device is embodied to excite the mechanically oscillatable unit by means of an excitation signal such that mechanical oscillations are executed, to receive the mechanical oscillations of the oscillatable unit, to convert them into a first received signal, to transmit a transmitted signal, and to receive a second received signal. The electronics unit is embodied, based on the first and/or second received signal, to determine the at least one process variable of the medium.

A device and a method for determining and/or monitoring at least one process variable of a medium include a sensor unit having a mechanically oscillatable unit, at least a first piezoelectric element, a conductivity/capacitance detecting unit for determining and/or monitoring a conductivity and/or capacitance of the medium and an electronics unit. The device is embodied to excite the mechanically oscillatable unit by means of an excitation signal such that mechanical oscillations are executed, to receive the mechanical oscillations of the oscillatable unit, to convert them into a first received signal, to transmit a transmitted signal, and to receive a second received signal. The electronics unit is embodied, based on the first and/or second received signal, to determine the at least one process variable of the medium.

An electric kitchen appliance has a pot for receiving food to be processed using the electric kitchen appliance. An ultrasound transmitter and an ultrasound receiver are provided in order to determine the fill level of the food in the pot. The ultrasound transmitter and the ultrasound receiver are attached to the upper edge of the pot such that an ultrasound signal can be transmitted onto the surface of the food by the ultrasound transmitter, and an ultrasound signal reflected by the surface of the food can be received by the ultrasound receiver. In this manner, an electric kitchen appliance is provided which allows the fill state of the food in the pot to be determined in a simple and reliable manner.

A self-sustaining sensor is provided, being configured to detect a fill level, a limit level, or a pressure of a medium or to measure an interface of a mixture of media in a transport container, the sensor including: a closed housing configured to be submerged in the medium; and a sensor element arrangement including one or more sensor elements arranged in or on the housing, in which the sensor is configured to rest on a bottom of the container and/or to float on a separating layer of the mixture of media during measurement, without being fixed to the container. A self-sustaining fill level measurement system, limit level measurement system, or pressure measurement system is also provided. A method for detecting a fill level or a limit level or a pressure of a medium or for interface measurement of a mixture of media in a transport container is also provided.