Universal joint with trunnion shaft seal assembly

1. A universal joint comprising:

a spider having a trunnion that includes a trunnion bearing surface, a trunnion sealing surface and a seal mount surface, the trunnion sealing surface and the seal mount surface being coaxial with the trunnion bearing surface;

a bearing cup having an open end, an inner bearing surface, and a bearing cup sealing surface, the bearing cup sealing surface being coaxial with the inner bearing surface;

a bearing disposed between the trunnion bearing surface and the inner bearing surface; and

a seal assembly sealingly engaged to the bearing cup and the spider, the seal assembly including a first portion and a second portion, the first portion being mounted on the seal mount surface and having a first annular wall member, a second annular wall member and a radially extending wall member that spaces the first and second annular wall members radially apart from one another so as to define an interior channel that is disposed coaxially about the trunnion, the second portion including a first seal member, a second seal member, a third seal member and a bumper, the first seal member being sealingly engaged to the trunnion sealing surface, the second seal member being sealingly engaged to one of the trunnion sealing surface and the first annular wall member, the third seal member being sealingly engaged to the second annular wall member, and the bumper contacting the radially extending wall member to limit axial movement of the second portion toward the first portion.

2. The universal joint of claim 1 , wherein the trunnion sealing surface is radially outwardly of the trunnion bearing surface.

3. The universal joint of claim 1 , wherein the second annular wall member includes a radially inwardly extending lip that is spaced apart from the radially extending wall and wherein contact between the third seal member and the radially inwardly extending lip limits axial movement of the second portion of the seal assembly away from the first portion of the seal assembly.

4. The universal joint of claim 3 , wherein the first seal member is disposed radially inwardly of the second seal member.

5. The universal joint of claim 4 , wherein the second portion of the seal assembly includes a frame member having a flattened “S” shape and wherein the frame member is abutted against an axial end face of the bearing cup.

6. The universal joint of claim 5 , wherein the frame member includes a first annular portion and a second annular portion, wherein the first seal member is mounted on the first annular portion, and wherein the second seal member, the third seal member and the bumper are mounted on the second annular portion.

7. The universal joint of claim 3 , wherein an end of the first annular wall member opposite the radially extending wall member has a reduced diameter lead-in.

8. The universal joint of claim 3 , wherein an undercut radius is formed into the second annular wall member between the radially extending wall member and the radially inwardly extending lip.

9. A universal joint comprising:

a spider having a trunnion that includes a trunnion bearing surface, a trunnion sealing surface and a seal mount surface, the trunnion sealing surface and the seal mount surface being coaxial with the trunnion bearing surface;

a bearing cup having an open end, an inner bearing surface, and a bearing cup sealing surface, the bearing cup sealing surface being coaxial with the inner bearing surface;

a bearing disposed between the trunnion bearing surface and the inner bearing surface; and

a seal assembly sealingly engaged to the bearing cup and the spider, the seal assembly including a first portion and a second portion, the first portion being mounted on the seal mount surface and having a first annular wall member, a second annular wall member and a radially extending wall member that spaces the first and second annular wall members radially apart from one another so as to define an interior channel that is disposed coaxially about the trunnion, the second portion including a first seal member, a second seal member, a third seal member and a bumper, the first seal member being sealingly engaged to the trunnion sealing surface, the second seal member being sealingly engaged to the first annular wall member, the third seal member being sealingly engaged to the second annular wall member, and the bumper contacting the radially extending wall member to limit axial movement of the second portion toward the first portion.

10. The universal joint of claim 9 , wherein the trunnion sealing surface is radially outwardly of the trunnion bearing surface.

11. The universal joint of claim 9 , wherein the second annular wall member includes a radially inwardly extending lip that is spaced apart from the radially extending wall and wherein contact between the third seal member and the radially inwardly extending lip limits axial movement of the second portion of the seal assembly away from the first portion of the seal assembly.

12. The universal joint of claim 11 , wherein the first seal member is disposed radially inwardly of the second seal member.

13. The universal joint of claim 12 , wherein the second portion of the seal assembly includes a frame member having a flattened “S” shape and wherein the frame member is abutted against an axial end face of the bearing cup.

14. The universal joint of claim 13 , wherein the frame member includes a first annular portion and a second annular portion, wherein the first seal member is mounted on the first annular portion, and wherein the second seal member, the third seal member and the bumper are mounted on the second annular portion.

15. The universal joint of claim 11 , wherein an end of the first annular wall member opposite the radially extending wall member has a reduced diameter lead-in.

16. The universal joint of claim 11 , wherein an undercut radius is formed into the second annular wall member between the radially extending wall member and the radially inwardly extending lip.

17. A universal joint comprising:

a spider having a trunnion that includes a trunnion bearing surface, a trunnion sealing surface and a seal mount surface, the trunnion sealing surface and the seal mount surface being coaxial with the trunnion bearing surface;

a bearing cup having an open end defining an end surface, an inner bearing surface, and a bearing cup sealing surface, the bearing cup sealing surface being coaxial with the inner bearing surface;

a bearing disposed between the trunnion bearing surface and the inner bearing surface; and

a seal assembly sealingly engaged to the bearing cup and the spider, the seal assembly including a first portion and a second portion, the first portion being mounted on the seal mount surface and having a first annular wall member, a second annular wall member and a radially extending wall member that spaces the first and second annular wall members radially apart from one another so as to define an interior channel that is disposed coaxially about the trunnion, the second portion including a a frame member, a first seal member, a second seal member, a third seal member and a bumper, the frame having first and second annular portions interconnected by an intermediate radial portion such that the first annular portion engages the bearing cup sealing surface and the intermediate radial portion engages the end surface of the bearing cup, the first seal member being mounted on the first annular portion of the frame and sealingly engaging the trunnion sealing surface, the second seal member being mounted on the second annular portion of the frame and sealingly engaging one of the trunnion sealing surface and the first annular wall member, the third seal member being mounted on the second annular portion of the frame and sealingly engaging the second annular wall member, and the bumper extending axially outward from the second annular portion of the frame and being configured to contact the radially extending wall member to limit axial movement of the second portion of the seal assembly toward the first portion of the seal assembly.

18. A universal joint comprising:

a spider having a trunnion that includes a trunnion bearing surface, a trunnion sealing surface and a seal mount surface, the trunnion sealing surface and the seal mount surface being coaxial with the trunnion bearing surface;

a bearing cup having an open end, an inner bearing surface, and a bearing cup sealing surface, the bearing cup sealing surface being coaxial with the inner bearing surface;

a bearing disposed between the trunnion bearing surface and the inner bearing surface; and

a seal assembly sealingly engaged to the bearing cup and the spider, the seal assembly including a first portion and a second portion, the first portion being mounted on the seal mount surface and having a first annular wall member, a second annular wall member and a radially extending wall member that spaces the first and second annular wall members radially apart from one another so as to define an interior channel that is disposed coaxially about the trunnion, the second portion including a first seal member, a second seal member, a third seal member and a bumper, the first seal member being sealingly engaged to the trunnion sealing surface, the second seal member being sealingly engaged to the first annular wall member, the third seal member being sealingly engaged to the second annular wall member, the bumper being configured to contact the radially extending wall member to limit axial movement of the second portion of the seal assembly toward the first portion of the seal assembly;

wherein the trunnion sealing surface is radially outwardly of the trunnion bearing surface;

wherein the second annular wall member includes a radially inwardly extending lip that is spaced apart from the radially extending wall and wherein contact between the third seal member and the radially inwardly extending lip limits axial movement of the second portion of the seal assembly away from the first portion of the seal assembly;

wherein the first seal member is disposed radially inwardly of the second seal member;

wherein the second portion of the seal assembly includes a frame member having a flattened “S” shape and wherein the frame member is abutted against an axial end face of the bearing cup;

wherein the frame member includes a first annular portion and a second annular portion, wherein the first seal member is mounted on the first annular portion, and wherein the second seal member, the third seal member and the bumper are mounted on the second annular portion;

wherein an end of the first annular wall member opposite the radially extending wall member has a reduced diameter lead-in; and

wherein an undercut radius is formed into the second annular wall member between the radially extending wall member and the radially inwardly extending lip.