Shaft rotation analyzer using variable capacitance transducer ma

Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

324686, 324176, 324177, 34087037, G01R 2726

Patent

active

049638297

ABSTRACT:
A variable capacitor whose capacitance is a function of shaft position is coupled to a rotating shaft. A constant voltage is applied to the capacitor. As the shaft rotates, the changing capacitance of the variable capacitance causes current to flow into and out of the variable capacitor in response to the shaft rotation--thus providing a current source with no inherent practical frequency response limitations. A transresistance amplifier converts the current to an output voltage which is proportional to instantaneous shaft velocity. Various arrangements are used to eliminate the discontinuity associated with the inherent sign change of the capacitance time derivative while retaining the signal components associated with instantaneous velocity changes of the rotating shaft. The broadband instantaneous velocity response of the resulting shaft rotation analyzer has numerous applications in the detection of "signatures" of rotating shafts--such as shaft speed variations attributable to electric motor commutator contact, cogging variations, and torque pulsations due to the firing of cylinders in reciprocating engines.

REFERENCES:
patent: 2929023 (1960-03-01), Mishcon et al.
patent: 2941397 (1960-06-01), Lee
patent: 3147374 (1964-09-01), Diamond
patent: 3225299 (1965-12-01), Middendorf
patent: 3702467 (1972-11-01), Melnyk
patent: 4007454 (1977-02-01), Cain et al.
patent: 4072051 (1978-02-01), Peterson
patent: 4142144 (1979-02-01), Rohr
patent: 4214483 (1980-07-01), Young
patent: 4350981 (1982-09-01), Tanaka et al.
patent: 4364046 (1982-12-01), Ogasawara et al.
patent: 4410852 (1983-10-01), Guretzky
patent: 4477810 (1984-10-01), Tanaka et al.
patent: 4482859 (1984-11-01), Fournier
patent: 4499465 (1985-02-01), Tanaka et al.
patent: 4641519 (1987-02-01), Klein et al.
patent: 4779094 (1988-10-01), Lee et al.
patent: 4839646 (1989-06-01), Tyson
Bryner et al, "Sliding Capacitive Displacement Transducer", NASA Tech Briefs, (Feb. 1987).
Tobey et al, Charge Amplifiers article, Operations Amplifiers: Design and Applications, pp. 233-235, McGraw-Hill, (1971).
Wolffenbuttel et al, "Capacitance-to-Phase Angle Conversion for the Detection of Extremely Small Capacities", IEEE Transactions on Instrumentation and Measurement, vol. IM-36, No. 4, pp. 868-872, (Dec. 1987).
"FET Op Amps Convert Photodiode Outputs to Usable Signals", Jerald Graeme, EDN, pp. 205-220, Burr-Brown Corp., (Oct. 29, 1987).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Shaft rotation analyzer using variable capacitance transducer ma does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Shaft rotation analyzer using variable capacitance transducer ma, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shaft rotation analyzer using variable capacitance transducer ma will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-851943

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.