Key operated piezoelectric signal generator - has crystal located on flexible metal backing which permits compact design and reduces danger of crystal rupture

摘要

The signalling key is esp. suitable for telephone installations and has a peizoelectric element fitted to a flexible metallic support (T), held at one end, which is flexed by the operation of the key (Ta). The support is provided with a pair of piezoelements (K, K) arranged one on each side. The piezoelectric material is deposited by a thin film deposition technique. The use of the flexible metallic carrier is compared with known systems applying flexure directly to a piezoelectric bar, reduces the danger of fracture of the crystal, and permits the use of thinner and more compact elements, with a wider tolerance in mfr.