摘要 |
A force measuring system includes a signal source for energizing a capacitance bridge arrangement. The bridge arrangement includes a pair of fixed capacitors and a pair of variable capacitors formed by a displaceable force sensitive element normally disposed in a null position between two fixed plates. A force applied to the system displaces the force sensitive element from the null position toward one or the other of the fixed plates to unbalance the bridge whereupon a signal is provided which is applied to a servo amplifier. The servo amplifier provides a signal which is applied to the displaceable force sensitive element, and which element is restored to the null position due to the electrostatic reaction occurring upon appropriate energization of the fixed plates. The signal provided by the servo amplifier is an accurate measure of the sensed force.
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