| abstract |
An improved precision lead screw and nut assembly, including an improved nut, includes a nondeformable screw member having a helical thread on the exterior thereof, the thread being formed by a rib having a crest, adjacent side walls, the rib defining a helical groove having a root which is located between the side wall of adjacent crests. The screw cooperates with a housing, the nut being positioned within the housing and cooperating with the screw such that relative rotation between the nut and the screw causes translational movement between the two. The nut includes a helical thread formed by a rib and adjacent side walls, the rib defining a helical groove having a root located between the side walls of the adjacent crests of the nut. The nut is preferably formed of a thermoplastic base material such as an acetal resin containing finely divided particles of a fluorocarbon resin such as polytetrafluoroethylene uniformly distributed throughout the base material. |