GB1055289A - Improvements in or relating to measuring instruments - Google Patents

Abstract

1,055,289. Load measuring instruments. INSTRUMATIC Ltd, J.A. EICHER and L.E. WILLIAMS. Sept.16, 1964 [Sept. 18, 1963], No. 36794/63. Heading G1W. In order to measure a load applied to a pivoted pointer 20 of a measuring instrument, the pointer 20 is pivoted about a shaft 23 and is attached to a toothed sector 22 which meshes with a pinion 26 connected to an indicator 28, Fig. 1 (not shown), the deflection of the pointer 20 due to a load being determined by the resilience of leaf springs 36, 37 which are fixed to a support block 12 and which bear at their free ends on an outer race ring of a ball bearing 38 attached to the sector 22. The leaf springs 36, 37 which are set such that only one of the springs is deflected at any one time may be of different strengths so that by suitably calibrating the scale of the indicator accurate measurements are obtainable by suitably selecting the direction of pointer deflection under a given load. The springs are curved at their free ends by an amount to ensure that the restoring torque they exert bears a rectilinear relationship to the angular displacement of the pointer 20. The shaft 23 is journalled in jewelled bearings of two frame plates 10, 11, Fig. 1 (not shown), which are supported from the block 12 mounted within a plastics casing 14 and a spiral spring 32 is arranged on the shaft 27 of the pinion 26 to prevent backlash between the pinion and the toothed sector 22.