| 摘要 |
PURPOSE:To make it possible to mass-produce hihg-precision wirstwatches by obtaining excellent frequency-temperatuer characteristics by electrically series-connecting two piezoelectric vibrarors under fixed conditions between the secondary temperature coefficient and equivalent capacity. CONSTITUTION:Frequency-temperature characteristics (curve 2) of tuning fork type bent crystal vibrator 5 is the secondary concave cirve and although secondary temperature coefficient (beta1) varies with a segmentation angle, (beta1) is equal to - 0.04 (ppm/ deg.C<2>). Frequency-temperature characteristics (curve 3) of lithium tantalate tuning fork type vibtator 6, on the other hand, draw the secondary concave curve and its secondary temperature coefficient (beta2) is nearly equal to + 0.08 (ppm/ deg.C<2>). Under the conditions of ¦beta2¦/¦beta1¦ C11/C12 denoting equivalent capacities of vibrators 5 and 6 by C11 and C12 respecitvely, two vibrators 5 and 6 are connected in series, so that the oscillation frequency of the oscillation circuit will vary according to extremely flat frequency-temperature characteristics like curve 4. |
