Development of high fatigue strength spring application on clutch disc torsional damper

摘要

We have developed a new torsional damper spring which lowers the torsional rigidity of the clutch disc while retaining its conventional size. The following two items have been adopted in the newly developed spring: 1) a new steel wire which suppresses any core-softening of the element wire through nitriding, and 2) a dual-stage shot peening method which uses harder steel shots (rather than conventional shots) in order to obtain an optimal residual stress profile. As a result of evaluating the fatigue characteristics of this spring, it was discovered that its fatigue strength is approximately 35% higher than that of the conventional spring. A clutch disc using this spring was able to absorb rattling noises which conventional clutch discs could not.