Patent ID: 8978434
Filing Date: 2015-03-17
Classification: B21F

Abstract:
1. A method for making a variable pitch spring, comprising the steps of: feeding spring wire feed forward at a spring wire feed speed to a rotary separator disk and to bending fingers, wherein the rotary separator disk has a bevelled edge with a varying profile along a length of the periphery of the rotary separator disk; synchronizing rotation of the rotary separator disk with movement of the wire at the spring wire feed speed; bending the spring wire using the bending fingers so as to impart a spiral configuration to the spring wire; placing the bevelled edge of the rotary separator disk between turns of the spring wire during formation of the turns to form a gap between the turns, wherein as a consequence of i) the varying profile of the bevelled edge, and ii) an instant angular position of the rotary separator disk, the bevelled edge defines a varying gap between the turns of the spring; and cutting the spring wire at an end of forming the spring.