| 摘要 |
<p>1425093 Piezoelectric vibrators SIEMENS AG and BRAUN AG 1 Feb 1973 [10 March 1972] 5067/73 Heading H2A In a bending mode piezo-electric vibration system, a bronze supporting strip 5, two piezoceramic strips 1, two sets of electrodes 3, 4, and two further supporting strips 2 are all rigidly fixed at one end in a body 6, and are set into transverse oscillation by appropriate energization at the electrodes. The supporting strips 2, are mechanically pre-stressed to apply pressure to each electrode 3, and are of such width that the bending stress in the adjacent parts of the strips 1 decreases in the direction towards the body 6, e.g. as curves 13, 14, Fig. 2. The strips 2 may have the shapes of Figs. 3-6 (not shown), and may be 5-30% as long as the overall length of the system. They may alternatively be as long as the zone having a curvature of constant sign and their stiffnesses may be in proportion to their lengths. The vibration system may have only one strip 1.</p> |
