Labyrinth bearing protector seal

A bearing protector spaced axially from a bearing means and coacting between a rotatable shaft and a surrounding housing for sealingly isolating the bearing means from a region disposed exterior of the bearing protector, said bearing protector comprising:

• a one-piece ring-shaped rotor adapted to be sealingly and nonrotatably carried on said shaft in surrounding relationshiip thereto, and a one-piece ring-shaped stator adatped to be sealingly and nonrotatably mounted on said housing;
• said stator being disposed radially in concentric and surrounding relationship to said rotor, said stator and rotor respectively having first and second annular surface means formed thereon and disposed in concentric and closely adjacent relationship to one another so as to define therebetween an elongate annular pathway which extends axially over a significant extent and at its inner end communicates with a bearing compartment and at its outer end communicates with the exterior region;
• said pathway including an inner passageway which is of very narrow width as defined between opposed portions of said first and second annular surface means for inhibiting flow therethrough, said inner passageway having a length which exceeds its width and defining the inner end of said pathway for direct communication with the bearing compartment;
• said pathway including an outer passageway which is of extremely narrow width as defined between opposed portions of said first and second annular surface means for inhibiting flow therethrough, said outer passageway having a length which exceeds its width and defining the outer end of said pathway for direct communication with the exterior region;
• said pathway including an intermediate passageway which is of very narrow width and is defined between opposed portions of said first and second annular surface means for inhibiting flow therethrough, said intermediate passageway having a length which exceeds its width;
• said pathway including means defining a first annular channel of enlarged radial and axial cross-sectional dimensions for collecting therein lubricant which tends to escape from said bearing compartment, said first channel being disposed for communication between the inner and intermediate passageways, said first channel being defined by a radially opposed pair of first channel-like grooves which are formed in said stator and rotor and which project respectively radially outwardly and inwardly from the respective first and second annular surface means so that said first channel is defined between maximum and minimum diameters, said inner and intermediate passageways respectively communicating with axially opposite sides of said first channel at positions which are spaced radially from and between the maximum and minimum diameters of said first channel;
• said stator having first drain opening means formed therein adjacent a lower side thereof for providing communication between said bearing compartment and a radially outermost portion of the first channel-like groove as defined in said stator;
• said pathway including means defining a second annular channel of enlarged radial and axial cross-sectional dimensions for collecting therein contaminants which flow into the pathway from the exterior region, said second channel being disposed for communication between the outer and intermediate passageways, said second channel also being positioned axially outwardly from said first channel and separated therefrom by said intermediate passageway, said second channel being defined by a radially opposed pair of secolnd channel-like grooves which are formed in said stator and rotor and which project respectively radially outwardly and inwardly from the respective first and second annular surface means so that said second channel is defined between maximum and minimum diameters, said outer and intermediate passageways respectively communicating with axially opposite sides of said second channel at positions which are spaced radially from and between the maximum and minimum diameters of said second channel;
• and
• said stator having second drain opening means formed in a lower portion thereof for providing communication between a radially outer portion of the second channel-like groove as defined in said stator and said exterior region.

In combination, a shaft rotatable about its longitudinally extending axis, a housing disposed in surrounding relationship to the shaft and defining therein a cylindrical bore which concentrically surrounds the shaft, bearing means coacting between said housing and said shaft for rotatably supporting said shaft, and a bearing protector associated with said cylindrical bore at a location spaced axially outwardly from said bearing means and coacting between said shaft and said housing for sealingly isolating the bearing means from a region which is disposed exteriorly of the bearing protector, said bearing protector including a ring-shaped rotor sealingly and nonrotatably carried on said shaft and disposed for cooperation with a ring-shaped stator which is sealingly and nonrotatably mounted on said housing at least partially within said cylindrical bore, comprising:

• said stator being disposed radially in concentric and surrounding relationship to said rotor, said stator and rotor respectively having first and second annular surface means formed thereon and disposed in concentric and closely adjacent relationship to one another so as to define therebetween an elongate annular pathway which extends axially over a significant extent and at its inner end communicates with a bearing compartment and at its outer end communicates with the exterior region;
• said pathway including an inner passageway which is of very narrow width as defined between opposed portions of said first and second annular surface means and which defines the inner end of said pathway for direct communication with the bearing compartment;
• said pathway including an outer passageway which is of extremely narrow width as defined between opposed portions of said first and second annular surface means and which defines the outer end of said pathway for direct communication with the exterior region;
• said pathway including an intermediate passageway which is of very narrow width and is defined between opposed portions of said first and second annular surface means;
• said pathway including means defining a first annular channel of enlarged radial and axial cross-sectional dimensions for collecting therein lubricant which tends to escape from said bearing compartment, said first channel being disposed for communication between the inner and intermediate passageways, said first channel being defined by a radially opposed pair of first channel-like grooves which are formed in said stator and rotor and which project respectively radially outwardly and inwardly from the respective first and second annular surface means;
• said stator having first drain opening means formed therein adjacent a lower side thereof for providing communication between said bearing compartment and the radially outermost portion of the first channel-like groove as defined in said stator;
• said pathway including means defining a second annular channel of onlarged radial and axial cross-sectional dimensions for collecting therein contaminants which flow into the pathway from the exterior region, said second channel being disposed for communication between the outer and intermediate passageways, said second channel also being positioned axially outwardly from said first channel and separated therefrom by said intermediate passageway, said second channel being defined by a radially opposed pair of second channel-like grooves as defined in said stator and rotor, said pair of second channel-like grooves extending radially outwardly and inwardly relative to their respective first and second annular surface means;
• said stator having second rain opening means formed in a lower portion thereof and providing communication between said exterior region and the radially outer portion of the second channel-like groove as defined in said stator;
• said stator including at least axially inner and outer annular portions, said inner annular portion being closely seated within the housing bore, said inner annular portion having an annular groove formed therearound and an elastomeric seal ring disposed within said groove and maintained in sealing engagement with the wall of said housing bore;
• said stator defining thereon an axially inwardly facing shoulder at the interface between said inner and outer annular portions so that said shoulder abuts an external front face of said housing when said stator is mounted thereon;
• and
• said outer passageway being defined in part by an axially-extending annular flange which is formed on the outer portion of said stator and projects axially outwardly thereof, and an axially-extending annular groove which is formed in said rotor and closely accommodates the annular flange therein so that the outer passageway includes portions which require flow therethrough in opposite directions, the rotor defining thereon an axially-inwardly projecting annular lip which is positioned radially outwardly of and projects in axially overlapping relationship relative to said flange.