GB1061284A - Strain sensing device - Google Patents

Abstract

1,061,284. Measuring strain. FORCE CONTROLS CO. Nov. 13, 1963 [March 13, 1963], No. 44746/63. Heading G1M. A strain gauge, which provides a signal when a given strain is reached, consists of two brackets 13, 14, Fig. 3 which are screwed to the member under test (not shown), and a bowed strip 16 secured between them which straightens under a tensile stress on the member and forces a probe button 53 to the right, thus placing a disc 62 across the poles 63 of a magnet 64 and causing an e. m.f. to be induced in a coil 65 wound on the magnet. Compressive stress is measured by starting with the strip straight and bowing it to the right. A yoke 54 rigidly links the brackets while they are screwed to the member under test when a preset bend is required in the strip, the yoke being then removed. A cylindrical member 27 is fixed to plates 23, 29 which are carried on the bracket 13, and carries a collar assembly 28 which is rotatable and which has grub screws 38 moving in a slot 39. The collar, by which the predetermined strain is set, carries a helically formed split ring 46 against which bears a ball 47 so that the axial position, in the cylinder 27, of the probe-carrying unit 34 depends upon the angular position of the collar. A plurality of screws 45 also Fig. 2 (not shown), adjust the contour of the split ring to linearise the strain scale (48) Fig. 1 (not shown), on the collar.