Patent ID: 7662240

Claim:
A method for improving the attributes of one or more seals of a worm gear assembly; the worm gear assembly comprising a worm having a worm shaft and a spiral thread; a worm gear having worm gear teeth; and a gear shaft extending from the center of the worm gear; the worm spiral thread and the worm gear being contained within a housing, and the worm shaft and gear shaft extending from the housing through openings in the housing; bearings supporting the worm and gear shafts and said seals, said seals surrounding the worm shaft and gear shaft and being positioned at the openings in the housing through which the worm shaft and gear shaft extend; the method comprising: reducing debris formation in the worm gear speed reducer assembly caused by adhesive and/or abrasive wear of the worm and worm gear during operation of the worm gear speed reducer assembly; said step of reducing debris formation comprising: supplying said worm wherein said worm is made from a hardened steel; wherein the worm was hardened by heating the worm to produce at least some austenite, quenching the worm and tempering worm; supplying said gear wherein said gear is made from a bronze; and concurrently developing nitrogen and carbon concentration gradients within the worm by gaseous nitrocarburizing, vacuum nitrocarburizing, ion nitrocarburizing or salt bath nitrocarburizing; and imparting a coating on one or both of the worm spiral thread and worm gear teeth.