Abstract: The present invention relates to a method for determining at least one physical characteristic value of an electromechanical oscillatory system, which comprises a piezoelectric element and at least one additional element coupled, with respect to oscillation, to the piezoelectric element, the piezoelectric element having an electrode and a counter electrode.

Abstract: The present invention concerns an ultrasonic vibration unit having a converter (1) for converting an electric ac voltage into a mechanical ultrasonic vibration and a sonotrode which is vibrationally coupled to the converter (1), wherein the sonotrode and the converter (1) are matched to each other in such a way that the ultrasonic vibration unit can vibrate with a natural frequency f, in which a standing longitudinal wave having at least one vibration node and at least two vibration antinodes is formed within the ultrasonic vibration unit.

Abstract: The present invention concerns an ultrasonic vibration device having a sonotrode and a converter, wherein the converter has a piezoelectric actuator for converting an electrical alternating voltage into a mechanical vibration, wherein there is provided a first piezoelectric sensor element which outputs a first measurement signal which varies in dependence on the vibration amplitude of the mechanical vibration. To provide an ultrasonic vibration device which allows measurement of at least one intensive state variable like for example the temperature or the ageing state of the piezoelectric actuator it is proposed according to the invention that there is provided a second piezoelectric sensor element which outputs a second measurement signal which varies in dependence on the vibration amplitude of the mechanical vibration, wherein the second piezoelectric sensor element differs in a physical property from the first piezoelectric sensor element.

Abstract: The present invention concerns an ultrasonic vibration unit having a converter (1) for converting an electric ac voltage into a mechanical ultrasonic vibration and a sonotrode which is vibrationally coupled to the converter (1), wherein the sonotrode and the converter (1) are matched to each other in such a way that the ultrasonic vibration unit can vibrate with a natural frequency f, in which a standing longitudinal wave having at least one vibration node and at least two vibration antinodes is formed within the ultrasonic vibration unit.

Abstract: In a method for influencing, in particular damping or suppressing, mechanical vibrations occurring during operation in a turbomachine blade (10), the mechanical vibratory energy of the turbomachine blade (10) is first converted into electrical energy and the electrical energy generated is then converted into heat loss. Effective damping which can be used especially simply and in a versatile way is achieved in that the piezoelectric effect is used in order to convert mechanical vibratory energy into electrical energy.

Abstract: In a method for influencing, in particular damping or suppressing, mechanical vibrations occurring during operation in a turbomachine blade (10), the mechanical vibratory energy of the turbomachine blade (10) is first converted into electrical energy and the electrical energy generated is then converted into heat loss. Effective damping which can be used especially simply and in a versatile way is achieved in that the piezoelectric effect is used in order to convert mechanical vibratory energy into electrical energy.

Abstract: Disclosed are a piezoelectric drive unit (10) and a method for operating such a drive unit in order to adjust movable parts (11), especially in a motor vehicle. Said piezoelectric drive unit (10) comprises at least one piezo motor (12) that is fitted with at least one piezo actuator (18). At least one frictional element (30) of the piezo motor (12) makes it possible to generate a relative movement in relation to a frictional surface (14) located across from the frictional element (30). Said at least one frictional element (30) is disposed on a bridging web (28) of the motor (12). The bridging web (28) places the frictional element (30) at a distance (2) from the central axis (89) of the at least one piezo actuator (18), said central axis (89) extending in a longitudinal direction (19).

Abstract: A measuring unit for determining the material parameters of a solid material sample of a substance includes a sample holder for accommodating the material sample to be tested, an actuator for generating an excitation vibration, a measuring unit and a measured value analysis unit, the actuator including at least one piezoelectric element to be electrically excited, and the actuator and the sample holder having a common longitudinal axis.

Abstract: An ultrasonic transducer having an ultrasonic conducting element with a plurality of arms extending from a common junction with some of the arms being provided with ultrasonic generators, at least one other arm carrying a bonding tool, especially for bonding a conductor to a chip and at least two of the arms including a straight angle of 180° with one another.

Abstract: A device for operating a tool has an ultrasound adapter with an capacitive electro-acoustic transducer (4) connected to an electrical ultrasonic frequency generator (8) for producing ultrasonic wave for a tool (2) driven by the device, wherein the capacitive electro-acoustic transducer (4) is connected with a secondary winding (5) and the ultrasonic frequency generator (8) is connected with a primary winding (7) of a transformer (6).

Abstract: An ultrasonic transducer having an ultrasonic conducting element with a plurality of arms extending from a common junction with some of the arms being provided with ultrasonic generators, at least one other arm carrying a bonding tool, especially for bonding a conductor to a chip and at least two of the arms including a straight angle of 180° with one another.

Abstract: A device for operating a tool has an ultrasound adapter with an capacitive electro-acoustic transducer (4) connected to an electrical ultrasonic frequency generator (8) for producing ultrasonic wave for a tool (2) driven by the device, wherein the capacitive electro-acoustic transducer (4) is connected with a secondary winding (5) and the ultrasonic frequency generator (8) is connected with a primary winding (7) of a transformer (6).

Abstract: A feed unit for moving parts over short distances has a four-bar chain forming a translating solid parallelogram having two parallel rigid opposite legs, one of which constitutes a base leg, connected to one another by elastic elements and a piezoelectric stack translator extending between and flexibly connected to the rigid legs for articulation relative to the rigid legs and oriented at an angle of incidence (&agr;) with respect to a base leg that is less than 90° and greater than 45°.

Abstract: A feed unit for moving parts over short distances has a four-bar chain forming a translating solid parallelogram having two parallel rigid opposite legs, one of which constitutes a base leg, connected to one another by elastic elements and a piezoelectric stack translator extending between and flexibly connected to the rigid legs for articulation relative to the rigid legs and oriented at an angle of incidence (&agr;) with respect to a base leg that is greater than 90° and less than 45°.

Abstract: An an ultrasonic drive element having a plurality of layers of piezoelectric material, arranged one on top of another to form a stack, between each of which is located a contacting layer for application of an operating voltage. Each of the contacting layers is subdivided into at least two electrically unconnected subregions, at least one of which has an electrode for making contact to the adjacent piezoelectric layers. By applying suitable alternating-current voltages to the electrode, the surface of the layer stack is excited into mechanical oscillations which contain a motion component parallel to the plane of said surface.