| 摘要 |
<p>1,131,942. Piezo-electric meters. SIEMENS, A.G. Jan.27, 1966 [Jan.28, 1965], No.3625/66. Heading G1Q. [Also in Division H1] A bending transducer, for use e.g. as the actuating element of a galvanometer, comprises a U-shaped polarized strip of electro-strictive material, e.g. barium titanate, provided on at least one surface with one or more pairs of interdigitated electrodes. Polarizaion is produced by applying the polarization voltage to the interdigitated electrodes as the strip cools from a temperature above the Curie point. This results in alternating zones of opposite polarizaion along the length of the strip. A signal applied to the electrodes results in either expansion or contraction of the surface layer of the strip according to the sign of the signal. If the electrodes and the polarizaion on either side of the strip form mirror images of each other, then signals applied in opposition to corresponding pairs of terminals on either side produce expansion of one side and contraction of the other side of the strip. The Figure shows a U-shaped strip, the limbs of which have been polarized oppositely to each other in such a manner that when the same signal is applied to both limbs, they bend in opposite directions out of the plane of the drawing. The transducer is anchored to a fixed base 17 and a mirror for reflection of a light beam is affixed to the free end.</p> |
