GB730174A - Improvements in hydraulic weighing scale pressure receivers - Google Patents

Abstract

730,174. Weighing-apparatus. AVERY, Ltd., W. & T. (Williams, L. S.). Oct. 20, 1950, No. 25565/50. Class 143. The invention relates to a hydraulic weighing scale of the kind having a load supporting platform 2 bearing on a plurality of hydraulic capsules 1 which each communicate pressure fluid to an associated bellows 5 adapted to convert the hydraulic pressure into force which is applied through a strut 9, a gathering lever 12 and a rod 16 to a steelyard 18; and consists in compensating for non-linear extension of the bellows 5 by inserting between the strut 9 and the lever 12 a plurality of pre-stressed spring plates 25 which have an initial curvature that increases with increases in load and so shortens the effective length of the strut 9 at an increasing rate as the load increases. In Fig. II four pairs of springs 25 extend between a pair of square blocks 26, 27 which are adjustable vertically by a nut 39 on a pre-stressing column 34, the block 27 having a groove in its base which co-operates with a knife edge 11 and lever 12. The force exerted by the spring bellows which tends to restore the lever 12 to a neutral position is also compensated by inserting a pair of spring plates 48 between a fixed bracket 50 and a lever extension 52 located vertically above the fulcrum 11a, the arrangement being such that a substantially constant force is applied to the lever by springs 48 at a moment arm which increases with movement of the lever, thus the' lever has a moment applied thereto which tends to accelerate its movements. Specification 640,911 is referred to.