Torque-limiting axle nut

Patent metadata

Field	Value
Publication number	US-12196243-B2
Application number	US-202318099803-A
Country	US
Kind code	B2
Filing date	Jan 20, 2023
Priority date	Jan 20, 2023
Publication date	Jan 14, 2025
Grant date	Jan 14, 2025

Abstract

A torque-limiting axle nut includes an inner nut having an inner-nut body forming a threaded center hole that defines a rotation axis. The inner nut also has a flange that encircles and extends radially away from the inner-nut body. The flange forms a plurality of recesses. The axle nut also includes a retaining ring encircling the inner-nut body and an outer nut encircling the inner-nut body. The outer nut forms grooves that extend axially upward from a bottom face of the outer nut and that extend azimuthally around the rotation axis. For each pair of neighboring grooves, the outer nut forms a ridge therebetween. The axle nut also includes a wave spring that encircles the inner-nut body and is located axially between the retaining ring and the outer nut. The axle nut also includes ball bearings seated in the recesses and extending into the grooves.

First claim

What is claimed is:

1. A torque-limiting axle nut, comprising:
an inner nut having:
an inner-nut body forming a threaded center hole that defines a rotation axis of the torque-limiting axle nut; and
a flange located azimuthally around the inner-nut body and extending radially away from the inner-nut body, the flange forming a plurality of recesses;

a retaining ring located azimuthally around the inner-nut body;
an outer nut located azimuthally around the inner-nut body, the outer nut forming a plurality of grooves that (i) extend axially upward from a bottom face of the outer nut and (ii) extend azimuthally around the rotation axis, wherein for each pair of neighboring grooves of the plurality of grooves, the outer nut forms a ridge that separates the neighboring grooves of said each pair;
a wave spring located azimuthally around the inner-nut body, the wave spring being located axially between the retaining ring and a top face of the outer nut; and
a plurality of ball bearings seated in the plurality of recesses and extending into the plurality of grooves.

2. The torque-limiting axle nut of claim 1 , the ridge having a front face that forms an obtuse angle with respect to a recessed surface of a first groove of said each pair of neighboring grooves.

3. The torque-limiting axle nut of claim 1 , the ridge having a rear face that forms a right angle or an obtuse angle with respect to a recessed surface of a second groove of said each pair of neighboring grooves.

4. The torque-limiting axle nut of claim 1 , the ridge having a bottom face that lies flush with the bottom face of the outer nut.

5. The torque-limiting axle nut of claim 1 , wherein:
the plurality of ball bearings identically have a ball-bearing diameter; and
the plurality of grooves identically have a radial width that is larger than the ball-bearing diameter.

6. The torque-limiting axle nut of claim 1 , the outer nut being shaped as a polygon.

7. The torque-limiting axle nut of claim 1 , the plurality of recesses being centered identically at a radial distance from the rotation axis.

8. The torque-limiting axle nut of claim 7 , the plurality of grooves being centered identically at the radial distance.

9. The torque-limiting axle nut of claim 1 , the plurality of grooves extending identically around the rotation axis by an azimuthal range.

10. The torque-limiting axle nut of claim 1 , the plurality of recesses being uniformly spaced around the rotation axis.

11. The torque-limiting axle nut of claim 1 , being unitized.

12. The torque-limiting axle nut of claim 1 , the retaining ring being engaged with a retaining-ring notch that extends radially inward from a cylindrical outer face of the inner-nut body.

13. The torque-limiting axle nut of claim 1 , the inner-nut body extending axially upward to form an extended portion that is shaped as a polygon, the extended portion forming an unthreaded center hole.

14. The torque-limiting axle nut of claim 1 , wherein:
the inner nut forms a plurality of plunger mounting holes extending axially upward from a bottom face of the inner nut;
the torque-limiting axle nut further comprises:
a plurality of spring plungers affixed in the plurality of plunger mounting holes; and
a locator plate forming a center unthreaded hole that is centered on the rotation axis, the locator plate forming a plurality of detent holes located azimuthally around the rotation axis; and

the locator plate faces the bottom face of the inner nut such that the plurality of spring plungers can engage with the plurality of detent holes as the inner nut rotates around the rotation axis.

15. The torque-limiting axle nut of claim 14 , the plurality of spring plungers being centered identically at a radial distance from the rotation axis.

16. The torque-limiting axle nut of claim 15 , the plurality of detent holes being centered identically at the radial distance.

17. The torque-limiting axle nut of claim 14 , the plurality of spring plungers being uniformly spaced around the rotation axis.

18. The torque-limiting axle nut of claim 14 , the locator plate forming a key shaped to engage with a slot of a threaded axle to rotationally constrain the locator plate relative to the threaded axle.

19. The torque-limiting axle nut of claim 14 , each of the plurality of detent holes being shaped as a countersunk hole or a countersunk stadium.

20. The torque-limiting axle nut of claim 14 , being unitized.

21. The torque-limiting axle nut of claim 1 , wherein:
the plurality of ball bearings identically have a ball-bearing diameter;
the flange has an axial thickness less than the ball-bearing diameter; and
each of the plurality of recesses is a through hole.

22. The torque-limiting axle nut of claim 21 , further comprising a locator plate forming a center unthreaded hole that is centered on the rotation axis, the locator plate forming a plurality of detent holes located azimuthally around the rotation axis, the locator plate facing a bottom face of the inner nut such that the plurality of ball bearings can engage with the plurality of detent holes as the inner nut rotates around the rotation axis.

23. The torque-limiting axle nut of claim 22 , wherein:
the plurality of detent holes are centered identically at a radial distance from the rotation axis;
the plurality of recesses are centered identically at the radial distance; and
the plurality of grooves are centered identically at the radial distance.

24. The torque-limiting axle nut of claim 22 , the locator plate forming a key shaped to engage with a slot of a threaded axle to rotationally constrain the locator plate relative to the threaded axle.

25. The torque-limiting axle nut of claim 22 , each of the plurality of detent holes being shaped as a countersunk hole or a countersunk stadium.

26. The torque-limiting axle nut of claim 22 , being unitized.

Assignees

• Amsted Rail Co Inc

Inventors

• Ford Brian

Classifications

• F16B31/02 Primary

  for indicating {the attainment of a particular tensile load} or limiting tensile load {(apparatus for, or method of, determining value of torque or twisting moment for tightening a nut or other member similarly stressed G01L5/24)} · CPC title