Abstract: An ultrasonic transducer for use in a fluid medium includes at least one transducer core having at least one acoustic/electric transducer element. The ultrasonic transducer furthermore includes at least one decoupling element which is configured to reduce a structure-borne noise coupling between the transducer core and a housing. The decoupling element includes at least one porous plastic material, in particular a foamed plastic material. The porous plastic material includes at least one thermosetting polymer and/or at least one thermoplastic.

Abstract: An ultrasonic transducer for use in a fluid medium includes at least one piezoelectric transducer element, at least one matching body for the promotion of a vibrational coupling between the piezoelectric transducer element and the fluid medium, and at least one compensating body situated between the piezoelectric transducer element and the matching body for the reduction of thermal stresses, the compensating body having a coefficient of thermal expansion that is between a coefficient of thermal expansion of the piezoelectric transducer element and a coefficient of thermal expansion of the matching body.

Abstract: An ultrasonic transducer is described for use in a fluid medium. The ultrasonic transducer includes at least one piezoelectric transducer element and at least one matching element for promoting an oscillation injection between the piezoelectric transducer element and the fluid medium. The ultrasonic transducer also includes a housing (112), the piezoelectric transducer element being inserted in the housing. The housing has at least one opening facing the fluid medium, the matching element being inserted at least partially into the opening. The ultrasonic transducer also has at least one sealing element, which seals at least one intervening space between the matching element and the housing in such a way that an inner space of the housing is at least largely sealed from the fluid medium.

Abstract: A method for manufacturing an ultrasonic transducer for use in a fluid medium is described. The ultrasonic transducer includes at least one transducer core having at least one acoustic-electric transducer element. The ultrasonic transducer furthermore includes at least one housing which at least partially surrounds the transducer core and which has at least one opening facing the fluid medium. In the method, at least one sealing film is stretched and connected to the housing in the stretched state in such a way that the sealing film at least partially seals the opening.

Abstract: A device for producing a current pulse includes supply terminals for providing a power supply voltage, and a switch which is situated in a control current branch between the supply terminals, which switch is configured to switch a control current through the control current branch as a function of an actuation signal. The device also has a current mirror having a control transistor and a signal transistor, the control transistor being situated in series to the first switch in the control current branch, and the signal transistor being configured to provide the current pulse as a function of the control current through the control transistor.

Abstract: An ultrasonic transducer for use in a fluid medium includes at least one transducer core having at least one acoustic/electric transducer element. The ultrasonic transducer furthermore includes at least one decoupling element which is configured to reduce a structure-borne noise coupling between the transducer core and a housing. The decoupling element includes at least one porous plastic material, in particular a foamed plastic material. The porous plastic material includes at least one thermosetting polymer and/or at least one thermoplastic.

Abstract: A sensor measures a flow quantity of a medium using a first wave converter and a second wave converter which faces the first wave converter, each of which emits and receives sound waves, and a device calculates the flow quantity on the basis of a first wave transit time from the first wave converter to the second wave converter, and on the basis of a second wave transit time from the second wave converter to the first wave converter. The device includes a unit for limiting the change to the flow quantity. In this manner, and the measurement may be carried out more accurately.

Abstract: An ultrasonic sensor has at least two ultrasonic converters for transmitting and receiving ultrasonic signals, connected with a transmitting circuit and a receiving circuit. A switching device is provided, by which the ultrasonic converters are connected in series when in the transmission mode, and they are separated from each other when in the receiving mode.

Abstract: A method for manufacturing an ultrasonic transducer for use in a fluid medium. At least one piezoelectric transducer element is joined directly or indirectly to at least one matching member for promoting vibration coupling between the piezoelectric transducer element and the fluid medium. A matching member is used which has at least one porous molding of a polymer.

Abstract: An ultrasonic flow sensor, in particular for determining the flow velocity of a medium flowing through a pipeline, has at least one ultrasonic converter for transmitting and/or receiving ultrasonic signals, an oscillator, which is connected with the ultrasonic converter, and an evaluation unit, which determines a phase shift of the ultrasonic signal that was received, with respect to a reference signal. The evaluation unit includes a plurality of quadrature demodulators, which operate with different demodulation frequencies and each determine phase information about the ultrasonic signal that was received, and when a vernier unit is provided, which determines—based on the individual pieces of phase information—a phase angle or a quantity proportional thereto.

Abstract: An ultrasonic sensor has at least two ultrasonic converters for transmitting and receiving ultrasonic signals, connected with a transmitting circuit and a receiving circuit. A switching device is provided, by which the ultrasonic converters are connected in series when in the transmission mode, and they are separated from each other when in the receiving mode.

Abstract: An ultrasonic flow sensor, in particular for determining the flow velocity of a medium flowing through a pipeline, has at least one ultrasonic converter for transmitting and/or receiving ultrasonic signals, an oscillator, which is connected with the ultrasonic converter, and an evaluation unit, which determines a phase shift of the ultrasonic signal that was received, with respect to a reference signal. The evaluation unit includes a plurality of quadrature demodulators, which operate with different demodulation frequencies and each determine phase information about the ultrasonic signal that was received, and when a vernier unit is provided, which determines—based on the individual pieces of phase information—a phase angle or a quantity proportional thereto.