Abstract A ball screw and nut combination in which the nut is essentially cylindrical in configuration, is provided with internal threads and a plurality of openings extending generally tangentially into a thread groove and communicating with a helically formed groove or recess at the exterior in helical alignment with but spaced by a smooth cylindrical uninterrupted exterior surface of the nut from a similar helical groove communicating with a second opening communicating tangentially with a thread groove. A cover of sheet material such as metal or plastic is attached overlying the openings and helically extending grooves or channels, the cover having a helically extending groove communicating with said openings and recesses or channels and the smooth exterior surface of the nut to define an enclosed ball return passage interconnecting the openings.
A ball nut for association with an elongated ball screw, said nut being generally of cylindrical configuration provided with an internal ball receiving thread groove, said nut having at least a pair of openings extending from its exterior surface in substantially tangential relation to the internal thread groove, the exterior surface of said nut having inclined grooves of variable depth, each of said grooves being in communication with one of said openings and extending toward but terminating short of a similar inclined groove communicating with the second opening of the pair, a cover plate overlying a portion of the cylindrical exterior surface of said nut and having an internal groove of variable depth communicating with the pair of grooves formed in the exterior surface of said nut to define therewith and with the smooth uninterrupted cylindrical surface portion of the nut a continuous ball return passage.
Claim 2
Dependent Claim
146 words
A ball nut for association with an elongated ball screw, said nut being generally of cylindrical configuration provided with an internal ball receiving thread groove, said nut having at least a pair of openings extending from its exterior surface in substantially tangential relation to the internal thread groove, the exterior surface of said nut having inclined grooves of variable depth, each of said grooves being in communication with one of said openings and extending toward but terminating short of a similar inclined groove communicating with the second opening of the pair, a cover plate overlying a portion of the cylindrical exterior surface of said nut and having an internal groove of variable depth communicating with the pair of grooves formed in the exterior surface of said nut to define therewith and with the smooth uninterrupted cylindrical surface portion of the nut a continuous ball return passage.
Claim 3
Dependent Claim
36 words
A nut as defined in claim 1 in which a plurality of pairs of openings are provided in the nut and a corresponding number of internal grooves are provided at the interior surface of the cover.
Claim 4
Dependent Claim
33 words
A nut as defined in claim 1 in which the cover is formed of a thin shell of uniform thickness of plastic material deformed to the required configuration to provide the internal grooves.
Claim 5
Dependent Claim
45 words
A nut as defined in claim 3 in which said plastic shell, except for the portions deformed into the aforesaid grooves, is of generally cylindrical configuration and is adapted to be retained in close surface-to-surface relationship with the smooth exterior cylindrical surface of the nut.
Claim 6
Dependent Claim
88 words
A nut as defined in claim 4 in which the nut body has a generally radial opening extending into a thread groove at the interior of the nut, a ball deflector having a helically extending bar partially received in the thread groove in the nut, said bar having a stem extending through the radial opening and through an opening in said cover, and means retaining the stem against inward movement of the opening to retain the deflector bar in position and to retain said cover on said nut.