| 摘要 |
PURPOSE:To reduce dimensions of the resonator to make the piezoelectric porcelain plate small-size, by utilizing frequency rise type energy shutting-in of width longitudinal oscillation of the piezoelectric transverse effect. CONSTITUTION:Driving electrodes 2 and 2' are formed with width H1 smaller than H on both faces of the center of rectangular porcelain plane plate 1 (width H, length l0 and thickness t) polarized in the direction of thickness. Peripheral electrodes 3, 3', 4 and 4' are provided on all of or almost all of surface and reverse face in left and right end parts except the center in the longitudinal direction, and perioheral electrodes 3 and 4 and peripheral electrodes 3' and 4' on the surface and the reverse face which are opposite to each other respectively are short-circuited respectively, and lead leading-out terminals 5 and 5' are fitted. As a result, the cutoff frequency in the center becomes higher than that in peripheral parts, and frequency rise type energy shutting-in of transverse effect width longitudinal oscillation is realized in the center driving electrode part. |
