Socket assembly

1. A socket joint assembly, comprising:

a housing with an inner bore which extends along an axis from a first end to an open second end;

a ball stud including a ball portion that is received in said inner bore of said housing and including a shank portion that projects out of said inner bore through said open second end;

said ball portion having a first hemisphere, a second hemisphere, and an equator;

a backing bearing disposed in said inner bore of said housing adjacent said first end and having a bearing surface, said bearing surface having a semi-spherical portion that is in surface-to-surface contact with an outer surface of said first hemisphere of said ball portion of said ball stud, said bearing surface having a cylindrical portion that is in surface-to-surface contact with said equator of said ball portion of said ball stud, and said cylindrical portion extending with a constant diameter past said equator in a direction towards said open second end of said housing such that the equator can remain in contact with said bearing surface in response to movement of said ball portion in an axial direction towards said open second end of said housing;

an exit bearing disposed in said inner bore of said housing adjacent said open second end and being in surface-to-surface contact with said second hemisphere of said ball portion of said ball stud;

said exit bearing being spaced in an axial direction from said backing bearing by a gap which surrounds said ball portion of said ball stud;

a spring applying a biasing force on said exit bearing and preloading said exit bearing against said second hemisphere of said ball portion of said ball stud;

said backing bearing having a lubricant opening extending therethrough;

said backing bearing including a plurality of lubricant wells which are spaced around said bearing surface from one another for holding a lubricant; and

said backing bearing further including a plurality of lubricant grooves formed into said bearing surface and extending from said lubricant opening of said backing bearing to at least one of said lubricant wells for replenishing said at least one lubricant well during regreasing of said socket assembly and wherein at least one of said lubricant grooves extends along said cylindrical portion of said bearing surface past said equator of said ball portion of said ball stud for channeling lubricant to the gap between said backing and exit bearings.

2. The socket assembly as set forth in claim 1 wherein at least one of said lubricant wells extends less than fully through said backing bearing.

3. The socket assembly as set forth in claim 1 wherein at least one of said lubricant grooves extends from one of said lubricant wells to another of said lubricant wells.

4. The socket assembly as set forth in claim 1 wherein at least one of said lubricant grooves does not extend to any of said lubricant wells for allowing lubricant to pass said backing bearing during regreasing of said socket assembly.

5. The socket assembly as set forth in claim 1 further including a cover plate disposed in said inner bore adjacent said open second end.

6. The socket assembly as set forth in claim 5 wherein said open second end of said housing is deformed to trap said cover plate in said inner bore of said housing.

7. The socket assembly as set forth in claim 1 wherein said housing has a wall at said first end.

8. The socket assembly as set forth in claim 7 wherein said wall at said first end of said housing has a lubricant opening which is co-axially aligned with said lubricant opening of said backing bearing.

9. The socket assembly as set forth in claim 1 wherein said bearing surface of said backing bearing has a radius of curvature which matches a radius of curvature of said outer surface of said ball portion of said ball stud.

10. A method of making a socket assembly, comprising the steps of:

preparing a housing with an inner bore which extends along an axis from a first end to an open second end;

inserting a backing bearing with a bearing surface and with a lubricant opening into the inner bore of the housing, the bearing surface having a semi-spherical portion and a cylindrical portion;

inserting a ball portion of a ball stud into the inner bore of the housing such that a first hemisphere of the ball portion is in surface-to-surface contact with the semi-spherical portion of the bearing surface and such that an equator of the ball portion is in surface-to-surface contact with the cylindrical portion of the bearing surface of the backing bearing to facilitate relative rotation between the housing and the ball stud and wherein the cylindrical portion extends with a constant diameter past the equator in an axial direction towards the open second end of the housing;

inserting an exit bearing into the inner bore of the housing such that the exit bearing is in surface-to-surface contact with a second hemisphere of the ball portion of the ball stud and such that the exit bearing is spaced from the backing bearing by a gap which surrounds the ball portion of the ball stud;

inserting a spring into the inner bore and imparting a biasing force on the exit bearing to preload the exit bearing against the ball portion of the ball stud;

injecting a lubricant into the inner bore of the housing;

channeling the lubricant through a plurality of lubricant grooves formed into the bearing surface of the backing bearing from the lubricant opening of the backing bearing to at least one lubricant well formed into the backing bearing and extending less than fully through the backing bearing to fill the lubricant well with the lubricant; and

further channeling the lubricant through the plurality of lubricant grooves formed into the cylindrical portion of the bearing surface of the backing bearing past the equator of the ball portion of the ball stud and into the gap between the backing and exit bearings.

11. The method as set forth in claim 10 further including the step of channeling the lubricant from at least one lubricant well to another lubricant well through at least one lubricant groove.