Method for producing a spark wheel
AssigneeThe Gillette Company
InventorEdward M. Tuckerman
Life of this patent
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Abstract
A spark wheel blank is provided with spaced helical grooves and lands or the like, as in a conventional threading or knurling operation. The blank so prepared is forced coaxially through the bore of a broaching die having a plurality of circumferentially spaced cutting surfaces which cut spaced notches across the lands to form a plurality of axially and circumferentially spaced teeth on the blank. The spark wheel thus formed is then subjected to an additional broaching step to remove portions of the teeth formed in the first broaching step, providing sharpened teeth for improved sparking performance.
Claims4
In a method of producing a spark wheel including the steps of forming a plurality of spaced grooves and lands extending diagonally around the periphery of a cylindrical wheel blank and subsequently forcing said blank coaxially through the bore of a first broaching die having a plurality of circumferentially spaced cutting surfaces which cut spaced notches across said lands to form a plurality of axially and circumferentially spaced teeth on said blank, the improvement comprising:
- subjecting said blank to an additional broaching step to remove portions of said teeth formed by said first broaching die.
Dependencies are inferred from the claim text.