Design method of strengthened type few-piece variable cross section master spring at gap between parabolic segment and auxiliary spring

The invention relates to a design method of a strengthened type few- piece variable cross section master spring at a gap between a parabolic segment and an auxiliary spring, and belongs to the technical field of suspension steel plate springs. The design method disclosed by the invention comprises the following steps: firstly, according to the structure size and the elasticity modulus of each end and root strengthened type variable cross section master spring piece, determining the deformation coefficient Gx-Fi of an end point of each master spring piece, and the deformation coefficient Gx-CD of the Nth master spring piece at the contact point of a parabolic segment and the auxiliary spring; then according to the load when the auxiliary spring works, and the Gx-Fi, acquiring the end point force of the Nth master spring piece; finally, according to the thickness of a flat section of the root of the Nth master spring piece, FN and the Gx-CD, performing design on the gap between the master spring and the auxilia