High-production method and apparatus for making grooved resistance

Abstract

A high production method and apparatus by which flat, ribbon-like resistance wire stock is fed between male and female die rolls to produce ribbed or grooved strips which can be spiral wound into electrical heating coils of the type used in cigar lighters, ignitor plugs and the like. The ribbing or grooving of the ribbon enables the nesting of adjoining convolutions to be had. The imparting of the ribbed configuration to the ribbon is effected prior to the cutting and winding of the same into the spiral coil. In accomplishing this, cooperable male and female rolls, turning in opposite directions, engage opposite sides of, and rib the ribbon and thereafter cut it into lengths while it is still moving, this being done at a high production rate. After an annealing process, the cut strips of ribbon can be fed to a coiling machine which will coil them into a spiral shape. The feeding, confining, grooving and cutting procedures are automatically, sequentially and continuously carried out quickly and expeditiously.