Mechanical quantity sensor

Details Mechanical quantity sensor Mechanical quantity sensor

2008-04-08

2008-04-08

San Martin, J. (Department: 2834)

Electrical generator or motor structure

Non-dynamoelectric

Piezoelectric elements and devices

C310S314000, C310S317000, C310S319000

Reexamination Certificate

active

07355321

ABSTRACT:
A mechanical quantity sensor includes a current-to-voltage converter/signal adder circuit that converts electric current signals flowing through two piezoelectric vibrators into voltage signals. The piezoelectric vibrators receive stresses generated by a mechanical quantity, such as acceleration, in opposite directions. A voltage amplifier/amplitude limiter circuit amplifies an added signal obtained from the two voltage signals and limits its amplitude. A phase-difference-to-voltage converter circuit detects a difference in the phases of the added signal and a feedback voltage signal applied to an acceleration detection element. A phase shifter circuit controls the phase of the feedback voltage signal so that the phase is a predetermined phase. A filter circuit minimizes frequency components higher than an oscillation frequency in an unwanted frequency band. By increasing the resistance of resistors so as to increase the damping ratio, temperature stability is increased. Accordingly, abnormal oscillation is prevented by the filter circuit, and fluctuation in the characteristics is minimized by the phase control circuit.

REFERENCES:
patent: 6763726 (2004-07-01), Yamashita
patent: 7109636 (2006-09-01), Yamashita
patent: 2003/0164696 (2003-09-01), Yamashita
patent: 1296433 (1969-05-01), None
patent: 1 324 052 (2003-07-01), None
patent: 62-050630 (1987-03-01), None
patent: 2002-243757 (2002-08-01), None
patent: 2003-254991 (2003-09-01), None
International Search Report for PCT Application No. PCT/JP2004/007248; mailed Sep. 14, 2004; International filing date, May 27, 2004.
Official communication issued in the counterpart German Application No. 11 2004 000 934.0, mailed on Aug. 8, 2007.

Affiliated with

Also associated with

Rating

Mechanical quantity sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Mechanical quantity sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mechanical quantity sensor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2794542