| 摘要 |
PURPOSE:To make an electronic timepiece small and thin by a method wherein an ultrasonic motor using a piezoelectric vibrator is constructed of rotor and stator members of an annular type and the inner periphery of the rotor member is provided with inner teeth. CONSTITUTION:An ultrasonic motor of an electronic timepiece is constructed of rotor and stator members of an annular type. The annular-type stator member is constructed of a piezoelectric vibrator 101 and a vibrating body 102,while the rotor member is constructed of a friction material 103, a moving body 104 and an inner-teeth gear 105. A driving force of the ultrasonic motor is transmitted from the gear 105 provided on inner periphery to the fifth wheel 106, the fourth wheel 107, the third wheel 108, a minute wheel 109, a data and back wheel 110 and a tube wheel 111. A second hand 112 is driven by the fourth wheel, a minute hand 113 by the minute wheel 109, and an hour hand 114 by the tube wheel. An oscillation circuit 118, a frequency-division circuit 119, a motor driving circuit 120 and a driving power source 121 are housed in the inner peripheral part of the motor. The timepiece can be made small and thin in this way. |
