Non-contact labyrinth seal assembly and method of construction thereof

1. A seal assembly, comprising:

an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of said assembly with a leg extending radially inwardly from said outer flange toward said central axis;

a seal body attached to said leg, said seal body having a radially outward lip and radially inward lip, said lips extending axially from said leg toward an air side of said assembly with said radially outward lip diverging outwardly from said central axis to provide a first annular channel between said lips and a second annular channel between said radially outward lip and said leg, said first annular channel facing axially toward said air side and said second annular channel facing radially outwardly from said central axis;

a sleeve having an axially extending cylindrical wall with an annular first flange extending radially outwardly from said cylindrical wall, said first flange having an annular projection extending axially toward said first annular channel; and

a labyrinth passage extending along said radially outward lip, continuoulsly from said radially outward lip, to an oil side of said assembly.

2. The seal assembly of claim 1 wherein said labyrinth passage maintains a substantially constant width between said lips and said annular projection.

3. The seal assembly of claim 1 wherein said annular projection is plastically deformed in said annular first flange.

4. The seal assembly of claim 1 wherein said seal body has an undulating surface facing radially inwardly toward said central axis, said labyrinth passage extending between said undulating surface and said cylindrical wall of said sleeve.

5. The seal assembly of claim 4 wherein said labyrinth passage has a generally constant width extending between said lips and said annular projection, and between said undulating surface and said cylindrical wall of said sleeve.

6. The seal assembly of claim 1 wherein said sleeve has an exclusion flange extending axially from said first flange in radially outward overlapping relation with said second annular channel.

7. The seal assembly of claim 6 wherein said seal body has an exclusion lip extending axially from said leg in overlapping relation with said exclusion flange.

8. The seal assembly of claim 7 wherein said exclusion lip is spaced from said exclusion flange to form said labyrinth passage extending between said exclusion lip and said exclusion flange.

9. The seal assembly of claim 8 wherein said exclusion lip is radially outward from said exclusion flange.

10. The seal assembly of claim 4 wherein said sleeve has a containment flange extending radially outwardly beyond said undulating surface.

11. The seal assembly of claim 10 wherein said seal body has a containment lip extending axially toward said oil side of said assembly in radially overlapping relation with said containment flange.

12. The seal assembly of claim 1 wherein said carrier and said seal body are formed as a single piece of the same material.

13. The seal assembly of claim 12 wherein said sleeve and said annular projection are formed as a single piece of the same material.

14. A seal assembly, comprising:

an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of said assembly with a leg extending radially inwardly from said outer flange toward said central axis;

a seal body attached to said leg, said seal body having a radially outward lip and radially inward lip extending axially from said leg and diverging radially from one another toward an air side of said assembly to form a generally frustroconical, annular first channel between said lips and an annular second channel between said radially outward lip and said leg;

a sleeve having cylindrical wall with an annular first flange extending radially outwardly from said wall into said first channel; and

wherein a labyringth passage extends between said seal body and said sleeve, from said air side to said oil side, during normal operation of said assembly.

15. The seal assembly of claim 14 , wherein said labyrinth passage is a purely non-contact labyrinth passage.

16. A method of constructing a seal assembly, comprising:

providing an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of the assembly with a leg extending radially inwardly from the outer flange toward the central axis;

providing a seal body on the leg, the seal body having a radially outward lip and radially inward lip, the lips extending axially from the leg toward an air side of the assembly with the radially outward lip diverging outwardly from the central axis to provide a first annular channel between the lips and a second annular channel between the radially outward lip and the leg, the first annular channel facing axially toward the air side and the second annular channel facing radially outwardly from the central axis;

providing a sleeve having an axially extending cylindrical wall with an annular first flange extending radially outwardly from the cylindrical wall, the first flange having an annular projection extending axially into the first annular channel; and

disposing the seal body about the sleeve such that a labyrinth passage is established, said labyrinth passage extending along said radially outward lip, continuoulsly from said radially outward lip, to an oil side of said assembly.

17. The method of claim 16 wherein the labyringth passage extends from the air side of the assembly to an oil side of said assembly during normal use.

18. The method of claim 17 further including causing said labyrinth passage to form a purely non-contact labyrinth passage extending from the air side to the oil side during normal use.