US4433590A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-backlash nut assembly
Assignee: Motion Control Inc
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Filing: 1981-08-28
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Granted: 1984-02-28
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Expires: 2001-08-28
Abstract
Abstract An anti-backlash nut assembly is disclosed for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and the screw. The assembly includes a first nut part having an internal thread complementary to the external thread of the screw, and a second nut part also having an internal thread complementary to the external thread of the screw. A coil spring is interconnected between the first and second nut parts for applying torque thereto and rotatably biasing the nut parts together to eliminate backlash therebetween and improve the positional accuracy of the nut assembly along the screw. A cylindrical collar is sandwiched between a pair of opposed portions of the nut parts and surrounds the coil spring. With this structural combination, the anti-backlash nut assembly can be adjustably preloaded by relatively rotating the nut parts to selectively preload the coil spring to a desired torque. The assembly then is rotated onto the screw with the torsion spring so preloaded.
Inventors
- 👤 Harold P. Benoit
- 👤 Leonard J. LaPasso
- 👤 Ian McBain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:59
CPC Classifications
F; F16; F16H; F16H25/00; F16H25/18; F16H25/20; F16H25/2003; F16H25/2006; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19623; Y10T74/19633; Y10T74/1987; Y10T74/19893; Y10T74/19898; Y10T74/19902
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
95 words
An anti-backlash nut assembly for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and screw, comprising: a first nut part having an internal thread complementary to the external thread of said screw; a second nut part also having an internal thread complementary to the external thread of said screw; and torsion means interconnected between said first and second nut parts for rotatably biasing said nut parts together to eliminate backlash and improve the positional accuracy of the nut assembly along the screw.
Claim 2
Dependent Claim
95 words
An anti-backlash nut assembly for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and screw, comprising: a first nut part having an internal thread complementary to the external thread of said screw; a second nut part also having an internal thread complementary to the external thread of said screw; and torsion means interconnected between said first and second nut parts for rotatably biasing said nut parts together to eliminate backlash and improve the positional accuracy of the nut assembly along the screw.
Claim 3
Dependent Claim
22 words
The anti-backlash nut assembly of claim 1 wherein said torsion means comprises a spring for applying opposing torque to said nut parts.
Claim 4
Dependent Claim
28 words
The anti-backlash nut assembly of claim 2 wherein said spring comprises a coil spring with opposite ends thereof each affixed to a respective one of said nut parts.
Claim 5
Dependent Claim
13 words
The anti-backlash nut assembly of claim 2, including a collar surrounding said spring.
Claim 6
Dependent Claim
21 words
The anti-backlash nut assembly of claim 4 wherein said collar is freely movable relative to said spring and said nut parts.
Claim 7
Dependent Claim
20 words
The anti-backlash nut assembly of claim 5, including means on said nut parts for positioning said collar about said spring.
Claim 8
Dependent Claim
27 words
The anti-backlash nut assembly of claim 6 wherein said last name means comprises opposed abutment shoulders on said nut parts for engaging opposite ends of said collar.
Claim 9
Dependent Claim
141 words
An anti-backlash nut assembly for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and screw, comprising: a first nut part having an internal thread complementary to the external thread of said screw; a second nut part also having an internal thread complementary to the external thread of said screw; a coil spring interconnected between said first and second nut parts for applying opposing torque forces to said nut parts and rotatably biasing said nut parts together to eliminate backlash and improve the positional accuracy of the nut assembly along the screw, the opposite ends of said coil spring each being affixed to a respective one of said nut parts; and a collar sandwiched between a pair of opposed portions of said nut parts and surrounding said coil spring.
Claim 10
Dependent Claim
141 words
An anti-backlash nut assembly for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and screw, comprising: a first nut part having an internal thread complementary to the external thread of said screw; a second nut part also having an internal thread complementary to the external thread of said screw; a coil spring interconnected between said first and second nut parts for applying opposing torque forces to said nut parts and rotatably biasing said nut parts together to eliminate backlash and improve the positional accuracy of the nut assembly along the screw, the opposite ends of said coil spring each being affixed to a respective one of said nut parts; and a collar sandwiched between a pair of opposed portions of said nut parts and surrounding said coil spring.
Claim 11
Dependent Claim
24 words
The anti-backlash nut assembly of claim 8 wherein said collar is cylindrical and freely rotatable relative to said coil spring and said nut parts.
Claim 12
Dependent Claim
30 words
The anti-backlash nut assembly of claim 8 wherein one of said nut parts has means for securing an operative component thereto for driving the component therewith longitudinally of said screw.
Claim 13
Dependent Claim
58 words
The anti-backlash nut assembly of claim 10 wherein one of said nut parts is a large dimensioned member having said securing means thereon, and the other of said nut parts is a small dimensioned member to facilitate preloading said coil spring by relative rotational positioning of said nut parts prior to assembly onto one end of said screw.
Claim 14
Dependent Claim
30 words
The anti-backlash nut assembly of claim 8 wherein said opposite ends of said coil spring are bent radially inwardly and are received in radial bores in said respective nut parts.
Claim 15
Independent Claim
129 words
A method of assembling and adjustably preloading an anti-backlash nut assembly for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and screw, comprising: providing a first nut part having an internal thread complementary to the external thread of said screw; providing a second nut part also having an internal thread complementary to the external thread of said screw; providing a torsion spring interconnected between said nut parts to bias said nut parts together; relatively rotating said nut parts to preload said torsion spring to a desired torque; and assembling said nut parts onto said screw with said torsion spring so preloaded to eliminate backlash and improve the positional accuracy of the nut assembly along the screw.
Claim 16
Independent Claim
129 words
A method of assembling and adjustably preloading an anti-backlash nut assembly for longitudinal movement along a screw which has an external thread thereon, in response to relative rotational movement between the nut assembly and screw, comprising: providing a first nut part having an internal thread complementary to the external thread of said screw; providing a second nut part also having an internal thread complementary to the external thread of said screw; providing a torsion spring interconnected between said nut parts to bias said nut parts together; relatively rotating said nut parts to preload said torsion spring to a desired torque; and assembling said nut parts onto said screw with said torsion spring so preloaded to eliminate backlash and improve the positional accuracy of the nut assembly along the screw.
Claim 17
Dependent Claim
130 words
An anti-backlash nut device which may be preloaded onto a screw which has an external thread, comprising: a first nut part having an internal thread complementary to the external thread of said screw; a second nut part also having an internal thread complementary to the external thread of said screw; and torsion means interconnected between said first and second nut parts, said torsion means being in a relaxed condition between said nut parts prior to assembly onto said screw whereby the nut parts can be relatively rotated to align the internal threads thereof and to preload said torsion means to bias said nut parts together whereafter the preload device can be placed onto said screw to eliminate backlash and improve the positional accuracy of the nut assembly along the screw.
Claim 18
Dependent Claim
130 words
An anti-backlash nut device which may be preloaded onto a screw which has an external thread, comprising: a first nut part having an internal thread complementary to the external thread of said screw; a second nut part also having an internal thread complementary to the external thread of said screw; and torsion means interconnected between said first and second nut parts, said torsion means being in a relaxed condition between said nut parts prior to assembly onto said screw whereby the nut parts can be relatively rotated to align the internal threads thereof and to preload said torsion means to bias said nut parts together whereafter the preload device can be placed onto said screw to eliminate backlash and improve the positional accuracy of the nut assembly along the screw.
Claim 19
Dependent Claim
22 words
The anti-backlash nut device of claim 14 wherein said torsion means comprises a spring for applying opposing torque to said nut parts.
Claim 20
Dependent Claim
28 words
The anti-backlash nut device of claim 15 wherein said spring comprises a coil spring with opposite ends thereof each affixed to a respective one of said nut parts.
Claim 21
Dependent Claim
13 words
The anti-backlash nut device of claim 15, including a collar surrounding said spring.
Claim 22
Dependent Claim
21 words
The anti-backlash nut device of claim 17 wherein said collar is freely movable relative to said spring and said nut parts.
Claim 23
Dependent Claim
20 words
The anti-backlash nut device of claim 18, including means on said nut parts for positioning said collar about said spring.
Claim 24
Dependent Claim
27 words
The anti-backlash nut device of claim 19 wherein said last named means comprises opposed abutment shoulders on said nut parts for engaging opposite ends of said collar.
Claim 25
Dependent Claim
30 words
The anti-backlash nut device of claim 14 wherein one of said nut parts has means for securing an operative component thereto for driving the component therewith longitudinally of said screw.
Claim 26
Dependent Claim
41 words
The anti-backlash nut device of claim 21 wherein one of said nut parts is a large dimensioned member having said securing means thereon, and the other of said nut parts is a small dimensioned member to facilitate preloading said torsion means.
Claim 27
Dependent Claim
31 words
The anti-backlash nut device of claim 14 wherein said torsion means comprises a coil spring having opposite ends thereof bent radially inwardly and received in radial bores in said nut parts.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-27 | 1987-08-29 | 1988-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-27 | 1991-08-29 | 1992-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-27 | 1995-08-29 | 1996-02-28 | $7700.00 | Window Closed / Lapsed |