| 摘要 |
752,040. Piezo-electric crystals. ELECTRIC MACHINERY MFG. CO. July 16, 1954 [July 20, 1953], No. 20763/54. Class 40 (8). A bender-type transducer comprises elements 11, 12 of barium or strontium titanate or a mixture thereof or barium zirconate joined together by a layer 13 of thermosetting resin. The element 11 has electrodes 14, 15 and the element 12 comb-like electrodes 18a, 18b so arranged that a source of potential 20 creates a voltage gradient across the element 11, and parallel to the length of the element 12. Thus the length of the strip 11 decreases while that of the strip 12 increases producing a large deflection in the transducer. In a modification, Fig. 5, a second series of transverse electrodes 25a, 25b are formed on the element 12, and are connected to electrodes 18. This arrangement produces a stronger voltage gradient parallel to the length of the element 12. In a further modification, Fig. 7, a strip of brass 30 is placed between the elements in electrical contact with the electrodes on each element. The potential may thus be applied between strip 30 and electrode 14 and between strip 30 and electrodes 18a, 18b. |
