Oscillator unit
US5561400A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 1995 |
| Grant date | Oct 1, 1996 |
| Priority date | — |
| Expiry date | Oct 4, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/5691
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electrical circuit for reliably starting the oscillation of an oscillator comprising a cylindrical piezoelectric body on which an exciting electrode, a feedback electrode which causes an oscillation, and an electrode for detecting an angular rate are mounted. The electrical circuit includes an exclusive OR gate for detecting a phase difference between an exciting voltage and a voltage developed at the feedback electrode, a circuit for integrating an output voltage from the gate and a band pass filter having its resonant frequency shifted in proportion to a voltage from the integrating circuit. The band pass filter is effective to provide an automatic adjustment of a phase difference of a voltage, which is actually fed back to the exciting electrode, with respect to a voltage developed at the feedback electrode. In this manner, if the natural frequency of the oscillator is offset from a reference value, it is assured that a phase difference between the exciting voltage and the voltage which is actually fed back to the exciting electrode be equal to 360.degree.. The electrical circuit also includes an oscillation starter circuit which increases the gain of a positive feedback loop…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.