Abstract: Presented is an apparatus that includes a vehicle component that includes an outer wall that includes an internal face and at least one electro-acoustic transducer disposed on the internal face of the outer wall of the vehicle component. The at least one electro-acoustic transducer includes a pot-type housing and a piezo-electric ceramic body disposed inside the pot-type housing. The pot-type housing includes a base area affixed to the internal face of the outer wall of the vehicle component.

Abstract: An ultrasonic transducer includes a housing, in which an ultrasonic oscillator is secured with at least one of a nonpositive and positive fit and at least three layers with acoustic wave impedances that vary to alternating degrees. The layers are arranged such that the ultrasonic oscillator is embedded in a first relatively acoustically soft layer, a second layer, which includes at least one relatively acoustically hard material, surrounds the first layer, and a third relatively acoustically soft layer at least partially surrounds the second layer.

Abstract: An ultrasonic transducer with a piezoceramic disk in radial resonance operation is created to produce a narrow main cone angle with suppresion of secondary cones. This is accomplished with the help of a ring surrounding the piezoceramic disk on its lateral face with a form fit and frictional engagement, this ring being made of a material whose longitudinal wave velocity is higher than that of aluminum.

Abstract: In an ultrasound transducer (1), a piezo-ceramic element (2) and an active materaial element (3) are joined to form a composite body in which the speed of sound is greater than in the piezo-ceramic element (2). This makes it possible to narrow the aperture angle .PHI. of the main sonic beam according to requirements.

Abstract: An ultrasonic transducer having a narrow principal lobe opening angle simultaneously with low secondary lobe amplitudes is provided. The ultrasonic transducer invention has a disk-shaped quarter-wave transformer element whose peripheral surface is configured as a stepped profile.

Abstract: For industrial applications, there is a need for compact ultrasonic transducers which at the same time have a radiation characteristic with small side lobes. This requirement is met by an ultrasonic transducer of conventional design and having a piezoelectric transducer element (1) which is bonded over its main surface (7) to a disk-shaped .lambda./4 matching element (2), it being the case according to the invention that the circumferential surface (3) of the .lambda./4 matching element is profiled with a notch (4) of suitable depth (5).

Abstract: For certain applications, such as detecting of glass breakage, it is advantageous to use frequency-selective ultrasonic transducers. In this case, one can dispense with using costly filter configurations to filter out relevant frequency components of the received ultrasonic spectrum. An ultrasonic sandwich transducer, which shows a high sensitivity for certain predetermined frequencies, can be produced by selectively adapting at least one of its geometric dimensions to the frequency selectivity which is required of the transducer. The ultrasonic sandwich transducer preferably has a piezoelectric-ceramic wafer, which is surrounded on at least one of its two wafer surfaces by a layer of low acoustical impedance. The piezoelectric-ceramic wafer is effectively rectangular, resulting in a block-shaped member. One of the dimensions of height, length and width is fixed to correspond to a desired fundamental frequency.

Abstract: A method for producing an ultrasound transformer as a single integral unit that includes a piezoelectric transformer element coupled to an acoustical matching layer formed from an elastomer capable of vibrating. The method includes the steps of: producing an elastomer body from a molded part which has centering contours; positioning the transformer element into the elastomer body; centering the transformer element with the centering contours; and, coupling the transformer element to the matching layer.

Abstract: In an ultrasonic sandwich transducer having an astigmatic sonic lobe, a small rectangular piezoceramic plate is operated on the fourth planar vibrational mode. To prevent the creation of secondary lobes that lead to spurious signals, damping elements are applied to the longitudinal ends of the ultrasonic sandwich transducer. These types of ultrasonic sandwich transducers find application, in ultrasonic proximity switches.