Patent EA-004668-B1 (EA)
Title: Electromechanical transducer
Inventor: BIRGEL DIETMAR
IPC: H04R17/00
Filed: 2001-05-16
Abstract: 1. An electromechanical transducer, which includes: piezoelectric elements (1, 3, 5, 7, 9, 11) disposed in a stack; between which, contact electrodes (G, S, E) are disposed, by way of which the piezoelectric elements (1, 3, 5, 7, 9, 11) are electrically connected, wherein the contact electrodes (G, S, E) are planar terminal lugs (33, 35, 37, 39, 41, 47, 55, 57, 59, 61, 63, 65, 67, 69, 77, 79, 81, 83, 85, 87, 89, 91) that are extended to the outside from a flexible printed circuit board (13, 13a, 13b, 13c). 2. The electromechanical transducer of claim 1, in which the flexible printed circuit board (13a) has one portion (17) embodied in step-like fashion; at each step (19, 21, 23, 25, 27, 29, 31), one planar terminal lug (33, 35, 37, 39, 41, 43, 45, 47, 49) is extended to the outside; and the steps (19, 21, 23, 25, 27, 29, 31) have a height that is equal to the thickness of the piezoelectric elements (1, 3, 5, 7, 9, 11) adjoining the respective step (19, 21, 23, 25, 27, 29, 31). 3. The electromechanical transducer of claim 1, in which the stack comprises at least two partial stacks disposed one on the other; and the piezoelectric elements (1, 3, 5, 7; 9, 11) of each partial stack are connected by means of terminal lugs (55, 57, 59, 61, 63, 65, 67, 69) of the flexible printed circuit board (13b) that are disposed around a bottom face (71, 73) associated with the partial stack and are extended to the outside from the printed circuit board (13b). 4. The electromechanical transducer of claim 1, in which the flexible printed circuit board (13c) has one portion (75) in which a plurality of conductor tracks extend one above the other, and in which each conductor track ends in a terminal lug (77, 79, 81, 83, 85, 87, 89, 91) extending perpendicular to the conductor track, and the individual terminal lugs (77, 79, 81, 83, 85, 87, 89, 91) are disposed parallel to one another and serve to connect piezoelectric elements (1, 3, 5, 7, 9, 11) adjoining them. 5. The electromechanical transducer of one of the foregoing claims, in which electronic components, in particular SMDs (49), are disposed on the flexible printed circuit board (13, 13a, 13b, 13c). 6. A method for producing an electromechanical transducer of one of the foregoing claims, in which the flexible printed circuit board (13, 13a, 13b, 13c) is equipped with components; the terminal lugs (33, 35, 37, 39, 41, 47, 55, 57, 59, 61, 63, 65, 67, 69, 77, 79, 81, 83, 85, 87, 89, 91) are disposed parallel to one another and one above the other by deformation of the flexible printed circuit board (13, 13a, 13b, 13c), as a result of which the piezoelectric elements (1, 3, 5, 7, 9, 11) are stacked on one another; and the stack is compacted. 7. The method of claim 6, in which the components are piezoelectric elements (1, 3, 5, 7, 9, 11) and SMDs (49), and the assembly is done automatically. 8. A device for ascertaining and/or monitoring a predetermined fill level in a container, which device includes: a mechanical oscillation structure to be mounted at the height of the predetermined fill level; and an electromechanical transducer (101) of one of claims 1-5, which in operation serves to set the mechanical oscillation structure into oscillation and pick up its oscillations that are dependent on an instantaneous fill level and make them accessible for further processing and/or evaluation.