Apparatus for Treating Coil Springs

Author:  William H. Wallace
Source:  US Patent 2,249,677
Doc ID:  1940002
Year of Publication:  1940
Abstract:  
My invention relates to coil springs and the art of treating the same to increase their useful life in comparison with similar springs as heretofore manufactured. The invention is particularly applicable to helical compression springs such as are commonly used as valve springs in internal combustion engines and as suspension springs in automobiles and the like, which are particularly susceptible to failure due to fatigue resulting from the repeated application of stresses thereto.