摘要 |
<p>PCT No. PCT/SE94/01160 Sec. 371 Date Aug. 1, 1997 Sec. 102(e) Date Aug. 1, 1997 PCT Filed Dec. 2, 1994 PCT Pub. No. WO96/17236 PCT Pub. Date Jun. 6, 1996A method of compensating for differences of temperature, in a pressure sensor of the kind wherein a pressure is sensed by use of a diaphragm connected in a Wheatstone bridge circuit. First measurement points of offset output signals emanating from the bridge in the pressure sensor at a number of temperature levels are plotted in a first graph indicating the voltage as a function of the resulting resistance of the bridge, whereupon adjacent measurement points are interconnected by straight lines and calculation is effected through interpolation between the measurement points. The sensitivity of the pressure sensor such as voltage/pressure unit, is determined in a corresponding manner at different temperature levels by plotting second measurement points in a second graph indicating the sensitivity as a function of the resulting resistance in a similar way the last mentioned measurement points are interconnected by straight lines, and calculation is effected through interpolation between the measurement points. The resulting curves are processed in a computer, whereupon a signal from the pressure reading provides a directly temperature-compensated pressure value which may be read from a third graph indicative of an output signal that is proportional to the prevailing pressure.</p> |