Seal case with over-molded rubber gasket securing plastic wafer

1. A seal case for a bearing seal, comprising:

an inner case encircling a rotation axis of the bearing seal;

an outer case encircling the rotation axis and including:

a ring-shaped frame with an inner side facing the inner case; and

a rubber gasket over-molded on the inner side of the ring-shaped frame, the rubber gasket forming ribs; and

a plastic wafer clamped between the inner case and the outer case, and secured at least by the ribs of the rubber gasket.

2. The seal case of claim 1 ,

the inner case including a first radial leg;

the ring-shaped frame including a second radial leg;

the plastic wafer including a third radial leg and a lip extending radially inwards from the third radial leg, the third radial leg being clamped between the first radial leg and a portion of the rubber gasket over-molded on the second radial leg.

3. The seal case of claim 1 , the rubber gasket being further over-molded on an outer side of the ring-shaped frame opposite the inner side.

4. The seal case of claim 1 , the rubber gasket including one or both of:

a radial lip extending from the ring-shaped frame toward the rotation axis; and

a axial lip extending away from an outer side of the ring-shaped frame opposite the inner side.

5. The seal case of claim 1 , the rubber gasket further including, extending away from an outer side of the ring-shaped frame opposite the inner side, a radially outward-facing ribbed section for engaging with a hub.

6. The seal case of claim 1 , the ribs comprising radial ribs that resist slippage of the plastic wafer.

7. The seal case of claim 1 , the ribs comprising circumferential ribs for sealing a leak path between the rubber gasket and the plastic wafer.

8. The seal case of claim 1 , the plastic wafer being formed from a material that attains a gel state when melted.

9. The seal case of claim 1 , the plastic wafer including polytetrafluoroethylene.

10. A bearing seal, comprising:

the seal case of claim 1 , the ring-shaped frame having an outer side opposite the inner side, the plastic wafer including:

a radial leg clamped between the inner case and the rubber gasket; and

a lip connected to an innermost diameter of the radial leg; and

a sleeve encircling the rotation axis and wrapping around (i) at least a portion of the outer side and (ii) a radially-innermost extreme of the seal case, the sleeve being rotatable about the rotation axis relative to the seal case, the sleeve including an inner-diameter leg that is radially inwards from the seal case and extends parallel to the rotation axis such that the inner-diameter leg engages with the lip.

11. The bearing seal of claim 10 , the rubber gasket including a radial lip extending from the ring-shaped frame toward the inner-diameter leg of the sleeve.

12. The bearing seal of claim 10 ,

the sleeve further including:

an outer-diameter leg that is radially outwards from the plastic wafer and extends parallel to the rotation axis; and

a middle section connecting between the inner-diameter leg and the outer-diameter leg, the middle section and the outer-diameter leg wrapping around the at least a portion of the outer side;

the bearing seal further comprising a thrust bumper seated in the rubber gasket on the outer side of the outer case, the thrust bumper facing an edge of the outer-diameter leg of the sleeve.

13. The bearing seal of claim 12 , the rubber gasket including one or both of:

a radial lip extending from the ring-shaped frame toward the inner-diameter leg of the sleeve; and

an axial lip extending from the ring-shaped frame toward the middle section of the sleeve.

14. A method for manufacturing a bearing seal, comprising:

over-molding a rubber gasket onto a ring-shaped frame to form an outer case, the rubber gasket forming ribs;

placing a plastic wafer between the rubber gasket and an inner case such that the plastic wafer contacts the ribs; and

securing the inner case to the outer case to form a seal case;

wherein the ribs include one or both of (i) radial ribs to resist slippage of the plastic wafer and (ii) circumferential ribs for forming a static seal between the rubber gasket and the plastic wafer.

15. The method of claim 14 , wherein said over-molding further includes molding a radial lip that extends radially inwards from a radially innermost edge of the ring-shaped frame.

16. The method of claim 14 , wherein said over-molding further includes molding an axial lip that extends away from an outer side of the ring-shaped frame opposite the plastic wafer.

17. The method of claim 14 , wherein said over-molding further includes molding a receptacle for a thrust bumper on an outer side of the ring-shaped frame opposite the plastic wafer.

18. The method of claim 14 , wherein said over-molding further includes molding a radially outward-facing ribbed section on a radially outward-facing portion of the ring-shaped frame.

19. The method of claim 14 , wherein said placing and securing cooperate to clamp the plastic wafer directly between the rubber gasket and the inner case.

20. The method of claim 14 , further comprising spin forming the ring-shaped frame and the inner case.

21. The method of claim 14 , further comprising:

disposing the seal case between a sleeve and a retainer ring, the sleeve wrapping around (i) an outer side of the outer case opposite the plastic wafer and (ii) a radially innermost extreme of the seal case closest to a rotation axis of the seal case, the retainer ring being on a side of the inner case opposite the plastic wafer; and

securing the retainer ring to the sleeve.

22. The method of claim 21 ,

further comprising seating, before said disposing, a thrust bumper in the rubber gasket on the outer side;

wherein said disposing includes positioning the sleeve such that an edge of the sleeve faces the thrust bumper.