Reinforced lead screw with anti-backlash nut

A reinforced lead screw assembly comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• an elongate bearing within the reinforcing rail having a slot aligned with the slot in the reinforcing rail;
• a nut-bearing moveable along the reinforcing rail;
• a portion of the nut extending through the slot;
• internal threads in the extending portion of the nut-bearing engageable with the threads on the lead screw for moving the nut in reciprocating motion lengthwise of the rail when the lead screw is rotated wherein the portion of the nut-bearing extending through the slots mounts a circular hub which has internal threads engageable with the threads of the lead screw.

A reinforced lead screw assembly comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow, elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• a nut-bearing moveable along the reinforcing rail;
• a portion of the nut extending through the slot;
• wherein the portion of the nut-bearing extending through the slot mounts a circular hub which has internal threads engageable with the threads of the lead screw for moving the nut-bearing in reciprocating motion lengthwise of the rail when the lead screw is rotated.

A reinforced lead screw assembly comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• an elongate bearing within the reinforcing rail having a slot aligned with the slot in the reinforcing rail;
• a nut-bearing moveable along the reinforcing rail;
• a portion of the nut extending through the slot;
• internal threads in the extending portion of the nut-bearing engageable with the threads on the lead screw for moving the nut in reciprocating motion lengthwise of the rail when the lead screw is rotated wherein the nut-bearing threads are formed on the portion of the nut extending through the slots in an arc.

A reinforced lead screw assembly comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• bearing surfaces forming the sides of the slot;
• an elongate sleeve-bearing within the reinforcing rail having a slot aligned with the slot in the reinforcing rail;
• a nut-bearing moveable along the reinforcing rail;
• a projection on the nut extending through the aligned slots and engageable with the bearing surfaces;
• threads on the nut-bearing engageable with the threads on the lead screw for moving the nut-bearing in reciprocating motion lengthwise of the rail when the lead screw is rotated wherein the projection mounts a circular hub which has internal threads engageable with the threads of the lead screw.

An anti-backlash nut assembly on a reinforced lead screw comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow, elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• an anti-backlash nut assembly having a nut moveable along the reinforcing rail;
• the anti-backlash nut comprising two separate nut portions;
• each nut portion having a tongue extending radially through the slot and having threads engageable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated;
• a compression spring for forcing the nut portions apart to urge the flanges of their threads into forcible engagement with the threads of the lead screw to prevent backlash while the anti-backlash nut translates laterally along the reinforcing rail.

A reinforced lead screw assembly comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• bearing surfaces forming the sides of the slot;
• an elongate sleeve-bearing within the reinforcing rail having a slot aligned with the slot in the reinforcing rail;
• a nut-bearing moveable along the reinforcing rail;
• a projection on the nut extending through the aligned slots and engageable with the bearing surfaces;
• threads on the nut-bearing engageable with the threads on the lead screw for moving the nut-bearing in reciprocating motion lengthwise of the rail when the lead screw is rotated wherein the nut-bearing threads are formed on the projection in an arc.

An anti-backlash nut assembly on a reinforced lead screw comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow, elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• an anti-backlash nut assembly having a nut moveable along the reinforcing rail;
• the anti-backlash nut comprising two separate nut portions;
• each nut portion having a tongue extending radially through the slot and having threads engageable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated;
• a coiled torsion spring for forcing the nut portions apart to urge the flanks of their threads into forcible engagement with the threads of the lead screw to prevent backlash while the anti-backlash nut translates laterally along the reinforcing rail.

An anti-backlash nut assembly on a reinforced lead screw comprising:

• a threaded lead screw rotatable about a central axis;
• a hollow, elongate reinforcing rail extending lengthwise of and surrounding the lead screw;
• a slot in the reinforcing rail extending lengthwise of the central axis;
• an anti-backlash nut assembly having a nut moveable along the reinforcing rail;
• the anti-backlash nut comprising two separate nut portions;
• each nut portion having a tongue extending radially through the slot and having threads engageable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated;
• and
• a coiled torsion spring for forcing the nut portions apart to urge the flanks of their threads into forcible engagement with the threads of the lead screw to prevent backlash while the anti-backlash nut translates laterally along the reinforcing rail.