GB854360A - Angular accelerometer - Google Patents

Abstract

854,360. Electric indicating systems. RESEARCH INTERESTS Ltd. (Montrose-Oster, L. E. W.). Feb. 5, 1957 [Feb. 6, 1956], No. 3622/56. Class 40 (1). [Also in Groups XIX and XX] An angular accelerometer comprises a real or virtual mass in neutral equilibrium mounted for movement in at least one direction but restrained against such movement by at least one pressure-sensitive element which produces an output as a function of pressure variations resulting from acceleration forces acting on the mass. The pressure-sensitive elements may be piezo-electrical crystals, carbon discs superimposed upon one another, or strain gauges. As shown (Fig. 1), masses 4, 4<SP>1</SP> at opposite ends of a lever arm 3 pivoted at 2, rest on pressure-sensitive elements 5, 5<SP>1</SP>. Angular acceleration in the plane of the arm 3 increases the pressure on one pile and decreases it on the other pile, the difference in pressure, which is gauged electrically in a bridge circuit (Fig. 5), being a measure of the angular acceleration. In another embodiment (Fig. 3), two identical gyroscopes 8, 8<SP>1</SP> rotating in opposite directions, act as virtual masses. The gyroscopes are coupled together by toothed sectors 9, 9<SP>1</SP> to balance turning movements about axes 16, 16<SP>1</SP> and 10, 10<SP>1</SP> are counterweights for these sectors. The gyroscopes are mounted in a frame 6 pivoted on stub axles 7, 7<SP>1</SP>. A lever arm 11 (similar to the arm 3 in Fig. 1), extends from the frame 6 and acts on two piles of discs 12, 12<SP>1</SP>, equivalent to the piles 5, 5<SP>1</SP> used in the bridge circuit of Fig. 5.