Geometrical instruments – Area integrators – Electrical
Patent
1984-05-29
1986-05-06
Stearns, Richard R.
Geometrical instruments
Area integrators
Electrical
33147N, G01B 702
Patent
active
045862605
ABSTRACT:
A scale and slider in a linear displacement measuring instrument have spaced opposed parallel surfaces bearing aligned patterns of thin flat conductive elements. The scale pattern consists of equally spaced parallel bars transverse to displacement with enlarged aligned central portions which form collectively a single set of coupling electrodes. A pair of aligned sensor electrodes are fixed on the surface of the slider opposite the coupling electrodes of the scale and matching arrays of transmitter elements are arranged on opposite sides of the sensor electrodes and grouped axially in space quadrature. Alternate interdigitated sets of the transmitter electrodes on the slider are excited with oppositely phased square wave signals. The signals picked up by the sensor electrodes on the slider are fed to separate coarse plate counting and fine plate interpolation circuits. In the fine count circuit, the displacement-dependent amplitude of the signals from first one and then the other of the sensor electrodes is amplitude demodulated and digitally converted by a dual slope integrator. The reference signal for the return slope is furnished by placing cophase signals on the transmitter electrodes. Battery life is prolonged by staged power down modes which remove bias voltages from selected analog components while retaining limit values.
REFERENCES:
patent: 2611964 (1952-09-01), Buisson
patent: 2915722 (1959-12-01), Foster
patent: 2924798 (1960-02-01), Foster
patent: 3219925 (1965-11-01), Borley et al.
patent: 3286252 (1966-11-01), Bose et al.
patent: 3593115 (1971-07-01), Dym et al.
patent: 3857092 (1974-12-01), Meyer
patent: 3895356 (1975-07-01), Kraus
patent: 3938113 (1976-02-01), Dobson et al.
patent: 3961318 (1976-06-01), Farrand et al.
patent: 4062120 (1977-12-01), Lacagnina et al.
patent: 4206401 (1980-06-01), Meyer
patent: 4237612 (1980-12-01), Christian et al.
patent: 4350981 (1982-09-01), Tanaka et al.
Dobson, "Position Encoder", IBM Technical Disclosure Bulletin, vol. 21, No. 1, pp. 242-243, (Jun. 1978).
Johnson, "Designing With Optical Shaft Encoders", Robotics Age, pp. 27-34, (May/Jun. 1983).
Technical Brochure, Farrand Controls Division of Farrand Industries, Inc., pp. 1-13, (first page entitled "Two Coils").
Sylvac Product Brochure, pp. 1-4.
Product brochure "Max-Cal: The Computerized Caliper", Brochure #83-03, Fred V. Fowler Co., Inc., (two pages) (1983).
Operating Instructions, Electronic Digital Caliper MAX-CAL, pp. 1-13, (reproduced on five pages).
Product brochure, "Goodbye Vernier . . . ", PAV Precision Caliper Gauge With Digital Display, four pages, Prazisions-Apparatebau Aktiengesellschaft.
Product brochure, "Making 15 Million Calipers Obsolete", The Jocal, C. E. Johansson, Fred V. Fowler Co., Inc. (four pages).
Product brochure, "The Future Is In Your Hands", (two pages), Brown & Sharpe Mfg. Co., (1982) (two pages).
Baxter Larry K.
Buehler Robert J.
Stearns Richard R.
The L. S. Starrett Company
LandOfFree
Capacitive displacement measuring instrument does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Capacitive displacement measuring instrument, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Capacitive displacement measuring instrument will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1567670