| 摘要 |
PURPOSE:To improve the frequency temperature characteristics by specifying the shape of piezoelectric vibrators in an electronic watch using two or more piezoelectric vibrators. CONSTITUTION:Piezoelectric vibrators 5 composed of crystal, etc. are formed in tuning fork type of less than 150mum in thickness and at least one is etched to provide tapers 12a, 12b to its vibrating arms 10a, 10b, so that a change is given to their width direction size over part or the whole of the length direction. These cause zero temperature coefficient temperature to be deviated by several degrees to the high temperature side without changing the value of secondary temperature coefficient too much, the zero temperature coefficient temperature on the high temperature side to be sufficiently increased, the spacing between the piezoelectric vibrators 5 to be taken wide, the frequency temperature characteristics to be corrected over a sufficiently wide temperature range and the watch accuracy to be improved. |
