Seal and scraper assembly

摘要

A seal and scraper assembly for a nut and screw actuator has an elastomeric member bonded to a metal ring. The elastomeric member has an annular lip outer portion and a helical thread form inner portion. The inner portion has a plurality of scraper or wiper surfaces interrupting the thread form at an oblique angle and cooperating with a lubricant return surface to direct lubricant, scraped from the screw thread surface, into the housing enclosing the nut and screw actuator. A web portion extends between the outer lip and the inner thread form along the same angle as each scraper surface so that a component of the assembly forces on the outer lip portion are transmitted to the scraper surface so as to increase the thread sealing and scraping forces. The metal ring has a contoured inner surface which is effective to chip ice and other foreign matter from the screw thread outboard of the elastomeric member and a pair of radially extending lugs which cooperate with recesses formed in the nut to prevent relative rotation between the nut and the seal and scraper assembly.