| 摘要 |
PURPOSE:To obtain a high-precision quartz wrist watch which has less frequency variation over a wide temperature range, by allowing one of two quartz oscillators connected in series or in parallel to perform flectional oscillation, and the other to perform torsional oscillation. CONSTITUTION:An quartz oscillator 12 whose temperature Tp corresponding to the peak frequency of frequency temperature characteristics (fT characteristics) is at a high temperature side as shown by a curve 22, and a quartz oscillator 11 whose temperature Tp is at a low temperature side as shown by a curve 21 are connected in parallel so that the oscillator 12 performs torsional oscillation, and the oscillator 11 performs flectional oscillation. Further, a quartz oscillator 31 which performs torsional oscillation with characteristics 41 having the positive gradient of variation in frequency with temperature, and a quartz oscillator 32 which performs flectional oscillation with characteristics 42 having the negative gradient are connected in series. Consequently, composite fT characteristics are as shown by a curve 23 and a chained line 43, obtaining a quartz oscillator having less frequency variation over a wide temperature range. A high-precision quartz wrist watch having superior shock resistance is obtained by employing a turning fork type as the quartz oscillator for the flectional oscillation or as both the quartz oscillators for the flectional oscillation and torsional oscillation. |
