Dry-lubricating lead-in edge for press-fit assemblies and associated methods
A dry-lubricating apparatus, for press fitting onto a mating part, includes (a) a frame, (b) a rubber gasket fixed to the frame to create an interference with a mating surface of the mating part so as to enable the press fitting, and (c) a lead-in edge fixed to at least one of the frame and the rubber gasket. The lead-in edge includes a dry lubricant such that, when the dry-lubricating apparatus is slid onto the mating part, along the mating surface and with the rubber gasket trailing the lead-in edge, a portion of the dry lubricant is abraded off the lead-in edge to reduce friction between the rubber gasket and the mating surface.
1. A dry-lubricating apparatus for press fitting onto a mating part, comprising:
a frame;
a rubber gasket fixed to the frame to create an interference with a mating surface of the mating part so as to enable said press fitting; and
a lead-in edge fixed to at least one of the frame and the rubber gasket, the lead-in edge including a dry lubricant such that, when the dry-lubricating apparatus is slid onto the mating part, along the mating surface and with the rubber gasket trailing the lead-in edge, a portion of the dry lubricant is abraded off the lead-in edge to reduce friction between the rubber gasket and the mating surface.
2. The dry-lubricating apparatus of claim 1 , the lead-in edge being chamfered or rounded.
3. The dry-lubricating apparatus of claim 1 , the frame being ring-shaped and having an inner-diameter leg defining a central aperture of the frame, the rubber gasket being fixed to a radially-inward facing surface of the inner-diameter leg.
4. The dry-lubricating apparatus of claim 3 , being a sleeve of a bearing seal.
5. The dry-lubricating apparatus of claim 1 , the frame being ring-shaped and having an outer-diameter leg, the rubber gasket being fixed to a radially-outward facing surface of the outer-diameter leg.
6. The dry-lubricating apparatus of claim 5 , being a seal case of a bearing seal.
7. The dry-lubricating apparatus of claim 1 , the rubber gasket forming an undercut for capturing a protruding ridge of the lead-in edge so as to lock the lead-in edge to the rubber gasket, the protruding ridge facing away from the mating surface when the dry-lubricating apparatus is slid onto the mating part.
8. The dry-lubricating apparatus of claim 1 , the lead-in edge being composed of a hydrophobic material.
9. The dry-lubricating apparatus of claim 1 , the lead-in edge being composed of a corrosion-resistant material.
10. The dry-lubricating apparatus of claim 1 , the lead-in edge including a thermoplastic.
11. The dry-lubricating apparatus of claim 10 , the lead-in edge being press fit onto the rubber gasket.
12. The dry-lubricating apparatus of claim 1 , the lead-in edge being composed of wax.
13. The dry-lubricating apparatus of claim 1 , the lead-in edge including at least one of graphite and molybdenum disulfide.
14. The dry-lubricating apparatus of claim 1 , the lead-in edge forming a chamfer that is at an angle between 15 and 30 degrees relative to the mating surface when the dry-lubricating apparatus is slid onto the mating part.
15. The dry-lubricating apparatus of claim 14 , the chamfer having a length in direction along which the lead-in edge is slid onto the mating part, the length being between one and five millimeters.
16. The dry-lubricating apparatus of claim 1 , the lead-in edge being rounded with a radius of curvature between one and five millimeters.
17. The dry-lubricating apparatus of claim 1 ,
the frame including a leading edge that is rounded or chamfered in a direction that, when the dry-lubricating apparatus is slid onto the mating part, is away from the mating surface; and
the lead-in edge including (a) a leading portion fixed directly to the leading edge, and (b) a trailing portion fixed to a leading end of the rubber gasket.
18. The dry-lubricating apparatus of claim 17 , the leading portion extending farther than the leading end in direction away from the mating surface, when the dry-lubricating apparatus is slid onto the mating part.
19. A method for dry-lubricated press-fit assembly of a first part onto a second part, comprising:
pressing the first part onto the second part by sliding the first part along a mating surface of the second part such that, during said sliding, the mating surface abrades a dry lubricant off a lead-in edge of the first part so as to reduce friction between the mating surface and a rubber gasket, of the first part, trailing the lead-in edge.
20. The method of claim 19 , the first part being a sleeve of a bearing seal, the second part being an axle.
21. The method of claim 19 , the first part being a seal case of a bearing seal, the second part being a hub assembly.
22. The method of claim 19 , further comprising disposing the lead-in edge on at least one of the rubber gasket and a frame of the first part.
23. The method of claim 22 , the lead-in edge being a solid ring, the step of disposing comprising press fitting the solid ring onto at least one of the frame and the rubber gasket.
24. The method of claim 23 , the step of press fitting comprising snapping a protruding ridge of the lead-in edge into an undercut in the rubber gasket.
25. The method of claim 22 , the step of disposing comprising:
applying softened wax onto at least one of the frame and the rubber gasket; and
allowing the wax to harden to form the lead-in edge from the wax.
26. The method of claim 22 , the step of disposing comprising disposing the lead-in edge on an inner-diameter leg of the frame where the inner-diameter leg connects to a radial leg of the frame, so as to form a dry-lubricating sleeve, for a bearing seal, configured to be press fit onto an axle.
27. The method of claim 22 , the step of disposing comprising disposing the lead-in edge on an outer-diameter leg of the frame at a terminal end of the outer-diameter leg, so as to form a dry-lubricating seal case, for a bearing seal, configured to be press fit onto an hub assembly.