Helical spring i.e. helical compression spring, for use in e.g. lorry as chassis spring, has multiple windings that are made of wire, where wire comprises thickening section with thickening provided within winding

摘要

The spring has multiple windings that are made of wire (3), where the wire comprises a thickening section (5) with a thickening (4) provided within the winding. A non-thickening section (7) lies opposite to the thickening section within the winding. The length of the thickening section is lesser than or equal to half of the length of a winding periphery. The thickening is formed by increasing or decreasing the cross-sectional areas (Qb, Qd) of the wire. The thickening is symmetrical to a wire axis.