Fiber reinforced bearing for a ball socket assembly, ball socket assembly therewith and methods of construction thereof

Patent metadata

Field	Value
Publication number	US-12281670-B2
Application number	US-202218049827-A
Country	US
Kind code	B2
Filing date	Oct 26, 2022
Priority date	Jul 17, 2018
Publication date	Apr 22, 2025
Grant date	Apr 22, 2025

Abstract

A ball socket assembly, bearing therefor, and method of construction thereof are provided. The ball socket assembly includes a housing with an inner bore extending between a closed first end region and an open second end region. A fiber-reinforced bearing is disposed in the inner bore. The bearing has a lower portion presenting a lower bearing surface having a first radius of curvature and an upper portion presenting an upper bearing surface having a second radius of curvature that is greater than the first radius of curvature. The lower bearing surface and the upper bearing surface surround a ball cavity in which a spherical ball portion of a ball stud is disposed. The housing second end region is plastically deformed radially inwardly to impart a bias on the bearing upper portion that causes the second radius of curvature to be biased substantially equal to the first radius of curvature.

First claim

What is claimed is:

1. A bearing for a ball and socket assembly, comprising:
a monolithic piece of fiber-reinforced plastics material including a lower portion presenting a lower bearing surface having a part spherical shape of a predetermined diameter of dimension A, the bearing further including an upper portion presenting an upper bearing surface having an inner surface that does not conform to the spherical shape of the lower bearing surface when the bearing is in an as-formed condition and which does conform to the spherical shape of the lower bearing surface when the bearing is biased to an assembled condition; and wherein the upper portion includes a plurality of slots defining a plurality of flexible fingers that circumscribe a mouth of the upper bearing surface having a diameter of dimension B when in the as-formed condition and a diameter of dimension C when biased inwardly to the assembled condition, and wherein the dimension B=0.5 (A+C).

2. The bearing of claim 1 , wherein the fiber reinforced plastics material consists of PBT having a glass fiber fill content of 10 volume % and a carbon fiber fill content of 5 volume %.

3. The bearing of claim 2 , wherein the slots have spaced side walls that are tapered along their length in the as-formed condition and are widest adjacent the mouth.

4. The bearing of claim 3 , wherein the side walls of the slots are spaced closer to one another when in the assembled condition.

5. The bearing of claim 4 , wherein the side walls are parallel when in the assembled condition.

6. The bearing of claim 1 , including an outer shoulder and wherein there are no slots below the shoulder.

7. The bearing of claim 1 , wherein the upper portion has a conical end face that is disposed at a 45 degree included angle relative to a central axis of the bearing when in the as-formed condition.

8. The bearing of claim 7 , wherein the conical end face is disposed at a relatively smaller included angle when in the assembled condition.

9. A ball and socket joint, comprising:
a housing with an inner bore extending along a central axis between a closed first end region and an open second end region;
a ball stud having an outer ball surface that forms part of a sphere with a predetermined diameter of dimension A;
a bearing received in the inner bore of the housing;
the bearing being fabricated of a single piece of bearing material and including a lower closed portion and an upper open portion collectively defining a socket;
the lower closed portion having an inner bearing surface with a part-spherical shape that conforms in size to the part of the sphere of the outer ball surface;
the upper open portion of the bearing having an inner surface extending from the lower closed portion inner surface, wherein the inner surface of the upper open portion has an as-formed first condition that does not conform to the shape and size of the sphere;
the upper open portion being biasable inwardly from the as-formed first condition to an assembled second condition in which the inner surface of the upper open portion fully conforms to the shape of the sphere;
the inner surface of the upper open portion defining a mouth at a distal end that has a first diameter of dimension B when in the as-formed first condition and a second diameter of dimension C when in the assembled second condition, wherein the dimension of B=0.5 (A+C); and
wherein the bearing material comprises fiber-reinforced plastics material and the bearing includes a plurality of circumferentially spaced longitudinal slots extending from the mouth to define a plurality of elastic wall segments of the upper open portion that flex outwardly to receive the ball-shaped end portion into the socket and which then return inwardly upon passage of the ball-shaped end portion, and wherein the open second region of the housing is plastically deformable inwardly to engage and bias the flexible wall segments and inner surface of the upper open portion of the bearing inwardly into the assembled condition against the ball-shaped end portion.

10. The ball and socket joint of claim 9 , wherein the bearing material consists of PBT with 10% by volume glass fiber fill and 5% by volume carbon fiber fill.

11. The ball and socket joint of claim 9 , wherein the plurality of slots each have an open end at the mouth and an opposite closed end axially away from the mouth and circumferentially spaced side walls, and wherein the side walls are non-parallel when the upper open portion is in the as-formed first condition.

12. The ball and socket joint of claim 11 , wherein the non-parallel side walls are tapered and are widest at the mouth.

13. The ball and socket joint of claim 12 , wherein the non-parallel side walls are generally V-shaped when the bearing is viewed from the side.

14. The ball and socket joint of claim 11 , wherein the side walls are generally parallel when the bearing is biased to the assembled second condition.

15. The ball and socket joint of claim 14 , wherein the slots extend below an equator of the ball surface.

16. The ball and socket joint of claim 15 , wherein the bearing includes an outer shoulder disposed below the equator and wherein there are no slots below the shoulder.

17. The ball and socket joint of claim 11 , wherein the bearing includes an outer shoulder and wherein there are no slots below the shoulder.

18. The ball and socket joint of claim 9 , including a preload member formed separately from the bearing and disposed in the bore between a base of the bore and an underside of the lower closed portion.

19. The ball and socket joint of claim 9 , wherein the upper open portion includes a conical end face that is disposed at 45 degree included angle relative to the central axis when the bearing is in the as-formed first condition.

20. The ball and socket joint of claim 19 , wherein the conical end face is disposed at a relatively smaller included angle than 45 degrees when the bearing is in the assembled second condition.

21. A method of making a ball and socket joint assembly, the method comprising:
preparing a ball stud having a shank portion and having a ball end of predetermined outer surface diameter A;
preparing a housing having a bore;
preparing a bearing fabricated of a single piece of bearing material and including a lower closed portion and an upper open portion defining a socket, and wherein the upper portion is formed with a plurality of flexible fingers separated by slots and defining a mouth of the socket at an upper and inner free edge of the fingers, and wherein the mouth has an as-formed first diameter of dimension B;
forcing the ball end of the ball stud axially into the mouth of the bearing and causing the fingers to flex outwardly to expand the mouth from the as-formed first diameter of dimension B to an outwardly-flexed diameter corresponding to the diameter A of the ball end, and continuing to move the ball stud axially into the bearing until the ball end is fully received into the socket upon which the fingers self-bias inwardly and the mouth returns to the as-formed first diameter of dimension B;
inserting the bearing into the bore of the housing;
plastically deforming the housing and flexing the fingers inwardly against the ball end to constrict the mouth from the as-formed first diameter of dimension B to a relatively smaller inwardly-flexed diameter of dimension C; and
wherein the bearing is dimensioned such that B=0.5 (A+C).

Assignees

• Fed Mogul Motorparts Llc

Inventors

• Chila Romit
• Elterman James
• Schrieber Dustin Oliver
• Englebright Seth

Classifications

• F16C11/0657 Primary

  the socket member being mainly made of plastics · CPC title

• F16C2208/70

  Polyesters, e.g. polyethylene-terephthlate [PET], polybutylene-terephthlate [PBT] · CPC title

• F16C2208/04

  Glass fibres · CPC title

• F16C2226/12

  by press-fit, e.g. plug-in · CPC title

• F16C11/0685

  Manufacture of ball-joints and parts thereof, e.g. assembly of ball-joints · CPC title