G01G3/00—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances
G01G3/02—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances wherein the weighing element is in the form of a helical spring
G01G3/04—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances wherein the weighing element is in the form of a helical spring using a plurality of springs