| 摘要 |
The invention concerns a device for maintaining oscillations of a vibrating device and vibrating device using said method. The vibrating device is designed to equip a unit carried close to the body, such as a timepiece, comprising a case, a mobile mass inside said case transmitting vibrations thereto, a coil (L) electromagnetically connected to said mobile mass to cau se it to oscillate, and an energizing circuit for said coil (L). The inventive method is characterised in that maintenance pulses (21, 22) of alternate polarity and specific duration (Tpulse) coinciding substantially with the extreme values of the movement-induced voltage (Uind, VB12) produced at the terminals of said coil (L) are generated. Each maintenance pulse (21, 22) is generated at the end of a specific and non-variable time interval (Tto-pulse ) calculated as from the average level crossing of the movement-induced voltag e, the time interval (Tfrom-pulse) taken by said movement-induced voltage to reach said average level crossing at the end of a maintenance pulse (21, 22) being determined by the instantaneous self-resonant frequency of the oscillation of the vibrating device so that an adaptation of the frequency a t which the maintenance pulses (21, 22) are generated is obtained.
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