BVM Engineering College ME-Machine Design

Wave SpringCreated By

Darshan M. Patel(140080709011)

Patent Description

Publication Number US005622358A

Application Number US 08/214,573

Publication Date Apr. 22, 1997

Filling Date Mar. 18, 1994

Priority Date Mar 29, 1993

Introduction

A wave spring is formed in which linear relation is retained between a load (P) and a defection (S).

In forming a spring structure by coiling a spring material having at cross section, a clothoid curve is selectively used as a shape-determining factor for the spring structure.

Spring Structure

A wave spring formed by winding a steel band having a flat cross section into a coil to serve as a spring structure is known . A wave spring 1 has predetermined numbers of ridges 2 and troughs 3 per turn circumferentially disposed at a predetermined pitch such that the upper end of a ridge in one coil layer is opposed to the lower end of said trough in an adjacent coil layer thus forming a spring structure.

Deformation Curve

Selection of coil shape , e.g. steel

Clutch device

Measuring Elastic Characteristic

Invention

A wave spring formed by coiling a spring material of flat cross section, said wave spring being characterized in that said spring material which circumferentially extends has a shape represented by a clothoid curve and in that linearity is retained in the relation between a load imposed on said wave spring and a deflection produced.

Since such clothoid curve has a characteristic in which the radius of curvature continuously varies in inverse proportion to the length of the curve.

Why cluthoid curve Selected

Single coil layer act as beam

Cluthoid curve is best suitable for linear relationship

Coil

Coil

Curve Improvement

Thank You