Method of Shot-Blasting Coil Springs

Author:  William H. Wallace
Source:  US Patent 2,341,674
Doc ID:  1942003
Year of Publication:  1942
Abstract:  
This invention relates to the shot-blasting of coil springs for increasing their useful life and aims to provide a novel method by which the shot-blasting treatment can be carried out more effectively than heretofore by moving the springs substantially in the direction of their longitudinal axes and along a relatively inclined path during their passage through the shot stream. Another object of my invention is to provide a novel method for shot-blasting coil springs in which the springs are moved substantially in the direction of their longitudinal axes and along a relatively inclined path during a first passage through the shot stream and are then reversed end-for-end and passed through the shot stream a second time. As a further object my invention aims to provide a novel method for shot-blasting coil springs made from wire or stock of rectangular cross-section in which such springs are passed through the shot stream in a manner to cause corresponding faces on one side of the spring convolutions to receive effective shot-blast treatment and then reversing the springs end-for-end and passing them through the shot stream a second time so that the other side faces of the convolutions will be effectively treated.