Dynamic shaft seal and method of installation thereof

1. A shaft seal for forming a dynamic seal along an axially extending annular running surface, comprising:

a mounting portion configured to be connected to a stationary housing;

a seal lip having an annular sealing surface extending between an oil side end and a free air side end, said sealing surface being configured to extend axially along the running surface, said oil side end having a greater diameter than said free air side end in an uninstalled state;

an annular bridge portion connecting the seal lip to the mounting portion;

a plurality of webs extending generally radially between said bridge portion and said mounting portion;

wherein said bridge portion includes a hinge region extending radially outwardly from said oil side of said seal lip at an angle less than 90 degrees from said seal lip and in reverse folded orientation over said seal lip toward said free air side end of said seal lip;

wherein an annular pocket is formed between said hinge region and said seal lip and an annular recess is formed between said hinge region and said mounting portion, said webs being equidistantly spaced circumferentially about said hinge region and extending from said hinge region to said mounting portion within said annular recess; and

wherein said annular pocket is free from support.

2. The shaft seal of claim l wherein said webs extend linearly between said hinge region and said mounting portion, adjacent ones of said webs extending in non-parallel relation to one another.

3. The shaft seal of claim 2 wherein ever other web extends generally parallel to one another.

4. A shaft seal for forming a dynamic seal along an axially extending annular running surface, comprising:

a mounting portion configured to be connected to a stationary housing;

a seal lip having an annular sealing surface extending between an oil side end and an air side end, said sealing surface being configured to extend axially along the running surface;

an annular bridge portion connecting the seal lip to the mounting portion;

a plurality of webs extending generally radially between said bridge portion and said mounting portion;

wherein said bridge portion includes a hinge region extending radially outwardly from said oil side of said seal lip in reverse folded orientation over said seal lip;

wherein an annular pocket is formed between said hinge region and said seal lip and an annular recess is formed between said hinge region and said mounting portion, said webs extending between said hinge region and to said mounting portion; and

wherein each of said webs have a pair of radially extending legs interconnected by an intermediate laterally extending leg.

5. A shaft seal, comprising:

a mounting portion configured to be connected to a stationary housing;

a seal lip having a backing surface and an opposite annular sealing surface extending between an oil side end and a free air side end, said sealing surface being configured to extend axially along a running surface of a rotating shaft, said oil side end having a greater diameter than said free air side end in an uninstalled state;

an annular hinge region extending radially outwardly from said oil side of said seal lip in reverse folded orientation over said seal lip toward said free air side end with an annular pocket being formed between one side of said hinge region facing said seal lip and said backing surface of said seal lip and an annular recess being formed between another side of said hinge region facing said mounting portion and said mounting portion,. said annular recess facing said oil side end; and

a plurality of reinforcing webs extending only through said recess between said hinge region and said mounting portion, said webs facing said oil side end and being equidistantly spaced circumferentially about said hinge region.

6. The shaft seal of claim 5 wherein said mounting portion has an outer diameter sized for an interference fit in a bore of the stationary housing.

7. The shaft seal of claim 6 wherein said outer diameter has a plurality of circumferentially extending ribs spaced from one another by an annular channel, said ribs being sized for partial compression and said annular channel remaining between said ribs upon being press fit into the bore.

8. The shaft seal of claim 5 wherein said webs extend linearly between said hinge region and said mounting portion, adjacent ones of said webs extending in non-parallel relation to one another.

9. The shaft seal of claim 8 wherein ever other web extends generally parallel to one another.

10. A shaft seal, comprising:

a mounting portion configured to be connected to a stationary housing;

a seal lip having a backing surface and an opposite annular sealing surface extending between an oil side end and an air side end, said sealing surface being configured to extend axially along a running surface of a rotating shaft;

an annular hinge region extending radially outwardly from said oil side of said seal lip in reverse folded orientation over said seal lip with an annular pocket being formed between one side of said hinge region facing said seal lip and said backing surface of said seal lip and an annular recess being formed between another side of said hinge region facing said mounting portion and said mounting portion;

a plurality of reinforcing webs extending through said recess between said hinge region and said mounting portion; and

wherein each of said webs have a pair of radially extending legs interconnected to one another by a laterally extending intermediate leg, said intermediate leg being spaced from said backing surface of said seal lip and said mounting portion.

11. The shaft seal of claim 10 wherein adjacent ones of said webs are mirror images of one another.