Spring winding machine with improved pitch mechanism

Abstract

A spring winding machine comprising a rotary cam shaft, a cam mounted on the shaft and rotatable therewith, and a follower on a lever intermediate its ends and engaged and driven in one and an opposite direction by the cam during each cam rotation. The lever is pivotally supported at one end and an opposite end drives a first slide in one and an opposite direction. A rack on the slide rotates a pinion on one and an opposite direction which in turn drives an electrical spindle drive means. The drive means includes a direct current tachometer generator and a fast response servo controller and motor which rotates the spindle in one and an opposite direction to wind springs thereon. A manually adjustable potentiometer predetermines the number of spindle turns for each cam rotation and thus establishes the number of spring coils. A second slide movable in one and an opposite direction is driven from the first slide by means of an angularly adjustable guideway on the first slide and a follower on the second slide. Adjustment of the guideway occurs about a point on the centerline of movement of the second slide so that a constant reference or starting point is maintained. The second slide drives an oscillable lever which in turn drives a conventional pitch rod in one and an opposite direction. The pitch rod is connected by a yoke with the spindle for free relative rotation but for axial driving movement of the spindle by the rod. Thus, the amount or extent of spindle axial or pitch movement is determined by the angular adjustment of the guideway and a constant starting point is provided for to maintain a constant wire feed or pass line, spindle readjustment for each pitch setting being thus eliminated.