TEMPERATURE COMPENSATING METHOD AND APPARATUS OF YAW RATE SENSOR

摘要

PURPOSE:To improve the compensating accuracy of temperatures by providing a capacity detecting electrode at one end of a piezoelectric vibrating member and connecting the electrode to a capacity detector which corrects the change of a vibration detecting signal resulting from the temperature characteristic of a piezoelectric body on the basis of the change of the capacity of the piezoelectric body. CONSTITUTION:A capacity detecting electrode 4 for detecting the capacity is provided at the inner and outer peripheral surfaces at one end of a base part of a cylindrical piezoelectric vibrating member 1. The electrode 4 is connected in parallel to a feedback resistance 22 of an operational amplifier 24 of a capacity detecting circuit 20. Therefore, a piezoelectric body held between the electrodes 4 constitutes an integrating circuit equivalent to a capacitor 23 of a capacity C. The integrating circuit outputs signals varying the voltage level depending on a time constant thereof. If the capacity of the piezoelectric body is increased as the temperature goes high, the time constant of the integrating circuit becomes large, whereby the level of the output signals of the integrating circuit is decreased. The output signals of the circuit 20 as above are connected to a gate terminal of a FET 7 of a voltage input-current output type via an output terminal 11. Accordingly, an output signal VS of an angular velocity detecting circuit 30 is compensated in temperatures.