Motor vehicle flywheel ignition timing ring manufacturing procedure uses blank which is first notched, then folded and finally calibrated

摘要

The procedure for making a ring with one or more peripheral marks on its edge (34) to adjust ignition timing, consists of first making notches in the edge of a flat disc blank before bending the edge over in a direction parallel to the flywheel axis and finally calibrating the ring. Each of the three stages is carried out in a single pass, the notching stage using a toothed matrix which is pressed axially against the disc blank to cut out a series of notches (24) to act as timing marks, the second stage uses a folding tool, and the third calibrating stage uses a guide tool (53) for the notches with teeth (56) and a calibrating tool (55) for the ring edge.