Abstract: An ultrasonic transducer for use in a fluid medium includes at least one housing having at least one inner space, at least one transducer core accommodated in the inner space, having at least one electroacoustic transducer element. The housing has at least one opening facing the fluid medium. The opening is covered at least partially by at least one sealing foil. An edge of the sealing foil is sealed by at least one sealing material.

Abstract: An ultrasonic flow sensor for detecting a flow of a fluid medium in a flow tube includes at least one first ultrasonic transducer, at least one second ultrasonic transducer, and at least one waveguide configured to conduct ultrasonic waves between the at least one first ultrasonic transducer and the at least one second ultrasonic transducer by reflection on walls of the waveguide, and to enable the fluid medium to flow through. The ultrasonic waves are able to propagate between the first ultrasonic transducer and the second ultrasonic transducer on at least two ultrasonic paths. Sound energies of the ultrasonic waves transmitted on the at least two different ultrasonic paths differ from one another by no more than a factor of 100.

Abstract: An ultrasonic flow sensor for use in a fluid medium is described. The ultrasonic flow sensor includes at least two ultrasonic converters which are situated in a flow tube offset relative to one another, longitudinally with respect to a flow of the fluid medium. The ultrasonic flow sensor also includes a reflection surface, the ultrasonic converters being set up to exchange ultrasonic signals via simple reflection on the reflection surface. In addition, a deflection device is provided between the ultrasonic converters which is set up to essentially suppress parasitic ultrasonic signals, which are reflected from the reflection surface and which strike the deflection device, by deflection away from the ultrasonic converters.

Abstract: A fuel vapor storage and recovery apparatus includes a fuel vapor storage canister, said fuel vapor storage canister comprising at least first and second vapor storage compartments filled with an absorbent material, for instance filled with activated carbon, at least a vapor inlet port, an atmospheric vent port and a purge port. Said fuel vapor storage canister defines an air flow path between said vapor inlet port and said atmospheric vent port during shut-off of the internal combustion engine of the vehicle. During purging cycles there is defined an air flow path between said atmospheric vent port and said purge port wherein said first and second vapor storage compartments are arranged in concentric relationship and wherein said first and second vapor storage compartments in flow direction are separated from each other by an air gap diffusion barrier.

Abstract: An ultrasonic transducer for use in a fluid medium includes at least one transducer core having at least one electroacoustic transducer element, and further includes at least one housing having at least two housing parts. At least one first housing part at least partially encloses the transducer core such that a rear side of the electroacoustic transducer element which faces away from the fluid medium is accessible. Furthermore, at least one second housing part is connected to the first housing part. The ultrasonic transducer is essentially terminated by the second housing part on its side, which faces away from the fluid medium.

Abstract: A method for measuring a propagation time difference includes: sending a transmitted ultrasound pulse, which is provided with a transmission reference instant and which includes an envelope and a carrier frequency, into a spatial region and receiving a received ultrasound pulse that corresponds to the transmitted ultrasound pulse transmitted. A coarse time difference is provided by comparing the transmission reference instant with an envelope of the received ultrasound pulse, for at least two cycles of transmission/reception in opposite directions of transmission. A fine time difference is provided by comparing the transmission reference instant with an instantaneous variation of the received ultrasound pulse, for the at least two cycles of transmission/reception in opposite directions of transmission.

Abstract: An ultrasonic transducer for use in a fluid medium is proposed. The ultrasonic transducer includes at least one transducer core which has at least one acoustic/electric transducer element, in particular a piezoelectric transducer element. The ultrasonic transducer furthermore includes at least one housing, at least one housing opening being at least partially sealed against the fluid medium with the aid of a sealing film which is connected to the transducer core. The sealing film has at least one expansion deformation which is configured to permit a relative movement between the transducer core and the housing.

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 microcontroller having a computing unit and a logic circuit. The microcontroller carries out computations for a regulation or control in a vehicle. The computing unit is connected to the logic circuit, and the logic circuit has an arrangement for computing an exponential function and is configurable.

Abstract: An ultrasonic measuring unit and a method for detecting ultrasonic signal run-times, in which the ultrasonic measuring unit has two ultrasonic transducers for coupling ultrasonic signals into a flowing medium. Analysis electronics are provided to be accommodated on or in a flow tube, in which a gaseous medium such as circulating air flows. A probe unit is accommodated in the flow tube, the probe unit being assigned a temperature probe having a flow around it, whose measured value is used for correcting a temperature signal detected by ultrasound.

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: A fuel vapor storage and recovery apparatus includes a fuel vapor storage canister, said fuel vapor storage canister comprising at least first and second vapor storage compartments filled with an absorbent material, for instance filled with activated carbon, at least a vapor inlet port, an atmospheric vent port and a purge port. Said fuel vapor storage canister defines an air flow path between said vapor inlet port and said atmospheric vent port during shut-off of the internal combustion engine of the vehicle. During purging cycles there is defined an air flow path between said atmospheric vent port and said purge port wherein said first and second vapor storage compartments are arranged in concentric relationship and wherein said first and second vapor storage compartments in flow direction are separated from each other by an air gap diffusion barrier.

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: The invention relates to a method for testing the operation of an electric heating element which is used for heating activated carbon of an activated carbon filter and/or air which is guided through the activated carbon for the regeneration thereof. The heating element has a PTC-characteristic (positive temperature coefficient characteristic). The strength of a current flow through the heating element in a heating phase selected for the operational testing is measured at a point in time or over a time period and is used for the operational testing, in that at least one measured current flow value is compared with a corresponding current flow value to be anticipated during defect-free operation of the heating element, and the heating element is considered to be defective in the event of a deviation which exceeds a predetermined measurement.

Abstract: A fuel vapor storage and recovery apparatus includes a fuel vapor storage canister, said fuel vapor storage canister comprising at least first and second vapor storage compartments filled with an absorbent material, for instance filled with activated carbon, at least a vapor inlet port, an atmospheric vent port and a purge port. Said fuel vapor storage canister defines an air flow path between said vapor inlet port and said atmospheric vent port during shut-off of the internal combustion engine of the vehicle. During purging cycles there is defined an air flow path between said atmospheric vent port and said purge port wherein said first and second vapor storage compartments are arranged in concentric relationship and wherein said first and second vapor storage compartments in flow direction are separated from each other by an air gap diffusion barrier.

Abstract: An active carbon filter intended for the fuel supply system of the internal combustion engine of a vehicle consists of a housing (1), inside of which flow paths for the different operating states of the filter are established between the ports (10, 11, 12) for connection with the top space of a tank, the ambient atmosphere and the intake manifold of the internal combustion engine. Proceeding from the port (11), these flow paths are characterized by chambers situated one in back of the other for pre-warming the air, an adjacent chamber (22) equipped with a first heating unit, an adjacent chamber (23) that accommodates active carbon particles, and another, adjacent chamber (28) that accommodates active carbon particles, is equipped with a second heating unit (34), and is provided with the ports (10, 12). This yields the establishment of optimal, in particular thermal conditions for the regeneration of the active carbon particles.

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.