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: 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: For determining the transit time of an ultrasonic signal from an ultrasonic sensor that was launched into a measurement path by an ultrasonic converter, the phase shift of the ultrasonic signal is determined relative to a reference timing signal, and a remainder is determined as a measure of the transit time of the ultrasonic signal so that the phase shift is determined using a quadrature demodulation scheme, with which the received ultrasonic signal is inverted, in a segmented manner, using a timing signal and a phase-shifted timing signal, and the remainder is determined based on a characteristic quantity of the ultrasonic signal.

Abstract: An ultrasonic flow rate meter and a method for measuring the flow rate with the aid of ultrasound are described, having at least two ultrasonic transducers situated offset in a flow channel in the flow direction for transmitting and receiving ultrasound wave packets, so that ultrasound propagation times from one of the ultrasonic transducers to the other, and vice-versa, can be determined in an electronic part, and having a pressure sensor associated with the flow channel for determining the pressure in the flow channel. Measured values for an engine control that is as accurate as possible are determinable by accurately detecting the incoming air in the intake of a motor vehicle internal combustion engine.

Abstract: An ultrasonic flow rate meter and a method for measuring the flow rate with the aid of ultrasound are described, having at least two ultrasonic transducers situated offset in a flow channel in the flow direction for transmitting and receiving ultrasound wave packets, so that ultrasound propagation times from one of the ultrasonic transducers to the other, and vice-versa, can be determined in an electronic part, and having a pressure sensor associated with the flow channel for determining the pressure in the flow channel. Measured values for an engine control that is as accurate as possible are determinable by accurately detecting the incoming air in the intake of a motor vehicle internal combustion engine.

Abstract: The invention relates to a method for determining the running time (t) of an ultrasound flow sensor (6) ultrasound signal (15) which is transmitted by an ultrasound transducer (A, B) to a measuring section (S), wherein the phase position (?F) of said ultrasound signal (15) is determined with respect to a reference clock (8) and a remaining part (r(t)) is determined as a measure of the running time (tmes) of the ultrasound signal (15). The measurement of the running time can be carried out in a particularly robust manner with a minimum use of hardware, when the phase position (?F) is determined with the aid of a quadrature-demodulation method consisting in inverting the received signal (15) in a segmented manner with the aid of a clock signal (8) and the phase of the off-set clock signal (9) and the remaining part (r(t)) is determined according to a characteristic quantity (ts) of the sound signal (15).

Abstract: The measurement of volume flows or mass flows in the intake system of motor vehicle internal combustion engines plays a significant role in reducing pollutant emissions. Therefore, an ultrasonic flow meter for measuring a flow rate of a fluid flowing in a primary flow direction is described. The ultrasonic flow meter has at least two ultrasonic transducers, the ultrasonic transducers being capable of emitting and/or receiving ultrasonic waves at an angle ? to the primary flow direction which is different from 90°. Furthermore, the ultrasonic flow meter has at least one guide element which is entirely or partially situated in the fluid. This guide element diverts at least one part of the flowing fluid in such a way that in the diversion, a velocity component is transferred to at least one part of the flowing fluid perpendicular to the primary flow direction. Guide vanes or displacers in particular are described as guide elements.

Abstract: The measurement of volume flows or mass flows in the intake system of motor vehicle internal combustion engines plays a significant role in reducing pollutant emissions. Therefore, an ultrasonic flow meter for measuring a flow rate of a fluid flowing in a primary flow direction is described. The ultrasonic flow meter has at least two ultrasonic transducers, the ultrasonic transducers being capable of emitting and/or receiving ultrasonic waves at an angle ? to the primary flow direction which is different from 90°. Furthermore, the ultrasonic flow meter has at least one guide element which is entirely or partially situated in the fluid. This guide element diverts at least one part of the flowing fluid in such a way that in the diversion, a velocity component is transferred to at least one part of the flowing fluid perpendicular to the primary flow direction. Guide vanes or displacers in particular are described as guide elements.