초록 ▼

The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant

The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. A preferably curved elevated contact pressure zone serves to maximize interfacial lubrication in critical areas during severe operating conditions by utilizing lubricant that would otherwise escape at the trailing edge of the hydrodynamic waves. The zones are produced by geometry that serves to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

대표청구항 ▼

1. A hydrodynamic rotary seal comprising: a generally circular seal body having a first body end and a second body end facing in generally opposite directions, said generally circular seal body comprising:a generally outwardly-facing static sealing surface;a dynamic sealing lip of generally annular

1. A hydrodynamic rotary seal comprising: a generally circular seal body having a first body end and a second body end facing in generally opposite directions, said generally circular seal body comprising:a generally outwardly-facing static sealing surface;a dynamic sealing lip of generally annular form projecting radially inward from said seal body and located radially inward from said static sealing surface and having a width that varies, said dynamic sealing lip comprising: a lubricant side flank, being a surface located in intermediate relation to said first and second body ends and located in spaced relation to said second body end, at least a portion of said lubricant side flank being skewed relative to said second body end;a generally inwardly-facing annular dynamic sealing surface located in intermediate relation to said lubricant side flank and said second body end and terminating at an abrupt exclusion edge of generally circular form that is located proximate said second body end;an inlet surface adapted for forming part of a hydrodynamic inlet upon installation, said inlet surface located between said lubricant side flank and said dynamic sealing surface, said inlet surface blending at least a portion of said dynamic sealing surface to at least a portion of said lubricant side flank, said lubricant side flank being radially outward of said inlet surface, said inlet surface providing a smooth blended axial transition to at least part of said dynamic sealing surface, said inlet surface defining first and second sloping inlet surfaces along an annular circumference of said dynamic sealing lip, each of said first and second sloping inlet surfaces having a convex curved form when viewed in longitudinal cross-section, at least a portion of said first sloping inlet surface being skewed relative to said abrupt exclusion edge, at least a portion of said second sloping inlet surface being skewed relative to said abrupt exclusion edge and substantially oppositely of the skewed portion of said first sloping inlet surface; anda ridge flank bounded by a ridge flank boundary, the entire said ridge flank boundary defining an external corner in an axial direction, said ridge flank located in intermediate relation to said first body end and said dynamic sealing surface and comprising a surface radially outward of said dynamic sealing surface, said ridge flank intersecting said dynamic sealing surface and said lubricant side flank to form portions of said ridge flank boundary, said ridge flank located in intermediate relation to and intersecting said first and second sloping inlet surfaces to form additional portions of said ridge flank boundary, at least a portion of said ridge flank boundary defining a ridge having a length along the annular circumference of said dynamic sealing lip, at least a portion of said first sloping inlet surface and at least a portion of said second sloping inlet surface being truncated by said ridge flank and said ridge;at least part of said ridge being curved along said ridge length relative to said abrupt exclusion edge so that some of said ridge is farther from said abrupt exclusion edge compared to a part of said ridge which is closer to said abrupt exclusion edge, there being a separating distance between said ridge and said abrupt exclusion edge; andwherein when viewed in longitudinal cross-section, no portion of said ridge flank is closer to said abrupt exclusion edge than said ridge. 2. The hydrodynamic rotary seal of claim 1, wherein said ridge is abrupt in the axial direction and becomes less abrupt along the length of said ridge as said ridge comes closer to said abrupt exclusion edge. 3. The hydrodynamic rotary seal of claim 1, wherein said ridge is abrupt with local curvature in the axial direction and varies in curvature along the length of said ridge. 4. The hydrodynamic rotary seal of claim 1, wherein said ridge extends between the skewed portions of said first and second sloping inlet surfaces. 5. The hydrodynamic rotary seal of claim 1, wherein at least part of said ridge is curved when viewed in longitudinal cross-section, and varies in axial position relative to said abrupt exclusion edge along the length of said ridge. 6. The hydrodynamic rotary seal of claim 1, wherein when viewed in longitudinal cross-section said ridge flank is substantially straight with an angle being defined between said ridge flank and said dynamic sealing surface, and said angle varies along the length of said ridge. 7. The hydrodynamic rotary seal of claim 1, wherein said ridge flank truncates at least a portion of said dynamic sealing surface. 8. The hydrodynamic rotary seal of claim 1, wherein said ridge flank truncates at least a portion of said lubricant side flank. 9. The hydrodynamic rotary seal of claim 7, wherein said ridge flank truncates at least a portion of said lubricant side flank. 10. The hydrodynamic rotary seal of claim 1, wherein said ridge is defined at least in part by a sharp intersection between said ridge flank and said first and second sloping inlet surfaces. 11. The hydrodynamic rotary seal of claim 1, wherein said ridge is defined at least in part by a rounded intersection between said ridge flank and said first and second sloping inlet surfaces. 12. The hydrodynamic rotary seal of claim 8, wherein said lubricant side flank varies in slope along the annular circumference of said dynamic sealing lip. 13. The hydrodynamic rotary seal of claim 1, wherein said ridge traverses along at least a portion of said inlet surface establishing an edge of said at least a portion of said inlet surface. 14. The hydrodynamic rotary seal of claim 1, wherein said ridge includes a portion curving towards said abrupt exclusion edge and a portion curving away from said abrupt exclusion edge along the length of said ridge. 15. The hydrodynamic rotary seal of claim 1, wherein said ridge flank is located between and adjoining said lubricant side flank and said dynamic sealing surface. 16. A hydrodynamic rotary seal having an annular seal body with generally oppositely facing first and second body ends, a generally outwardly facing static sealing surface, and an annular dynamic sealing lip located in intermediate relation to said first and second body ends and adapted for compressed contacting relationship with a relatively rotatable surface having a direction of relative rotation, the dynamic sealing lip having an abrupt, generally circular exclusion edge located axially remote from the first body end, and having a lubricant side flank and an inlet surface located in intermediate relation to the first body end and the exclusion edge, the lubricant side flank being radially outward of the inlet surface and the inlet surface comprising first and second sloping inlet surfaces having a convex shape when viewed in longitudinal cross-section, at least a portion of the first sloping inlet surface being skewed relative to the circular exclusion edge, at least a portion of the second sloping inlet surface being skewed relative to the circular exclusion edge and substantially oppositely of the skewed portion of the first sloping inlet surface, wherein the improvement comprises: the dynamic sealing lip including a ridge flank located in intermediate relation to the first body end and the exclusion edge, located in intermediate relation to the first and second sloping inlet surfaces, and separated by a distance from the exclusion edge, at least a portion of said ridge flank being radially outward of the first and second sloping inlet surfaces;said ridge flank intersecting the lubricant side flank and producing an external corner when viewed in longitudinal cross-section;a ridge defined in part by an external corner at an intersection of the first sloping inlet surface and said ridge flank and defined in part by an external corner at an intersection of the second sloping inlet surface and said ridge flank, the first and second sloping inlet surfaces being truncated by said ridge and said ridge flank, at least part of said ridge being curved so that some of said ridge is farther from the exclusion edge compared to a part of said ridge which is closer to the exclusion edge, there being a separating distance between said ridge and the exclusion edge;a first portion of said ridge establishing a boundary of at least a portion of the first sloping inlet surface and being skewed relative to the exclusion edge and skewed generally oppositely of the skewed portion of the first sloping inlet surface; anda second portion of said ridge establishing a boundary of at least a portion of the second sloping inlet surface and being skewed relative to the exclusion edge and skewed generally oppositely of the skewed portion of the second sloping inlet surface. 17. The hydrodynamic rotary seal of claim 16, wherein at least a portion of said ridge is abrupt in an axial direction and said ridge becomes less abrupt as said ridge comes closer to the exclusion edge. 18. The hydrodynamic rotary seal of claim 16, wherein said ridge has a length in a circumferential direction and said ridge in an axial direction has a rounded character that varies in curvature along the length of said ridge. 19. The hydrodynamic rotary seal of claim 16, wherein said ridge extends between the skewed portions of the first and second sloping inlet surfaces. 20. The hydrodynamic rotary seal of claim 16, wherein said ridge has a length in a circumferential direction, at least part of said ridge is curved when viewed in longitudinal cross-section, and varies in axial position relative to the exclusion edge along the length of said ridge. 21. The hydrodynamic rotary seal of claim 16, wherein said ridge has a length in a circumferential direction and said ridge flank has a slope that varies in an axial direction along the length of said ridge. 22. The hydrodynamic rotary seal of claim 16, wherein the dynamic sealing lip includes a dynamic sealing surface and said ridge flank truncates at least a portion of the dynamic sealing surface, at least a portion of the dynamic sealing surface being located between the exclusion edge and the inlet surface. 23. The hydrodynamic rotary seal of claim 22, wherein said ridge flank truncates at least a portion of the lubricant side flank. 24. The hydrodynamic rotary seal of claim 16, wherein said ridge is defined at least in part by a sharp intersection between said ridge flank and the first and second sloping inlet surfaces. 25. The hydrodynamic rotary seal of claim 16, wherein said ridge is defined at least in part by a rounded intersection between said ridge flank and the first and second sloping inlet surfaces. 26. The hydrodynamic rotary seal of claim 16, wherein at least a portion of said ridge is parallel to the exclusion edge. 27. The hydrodynamic rotary seal of claim 16, wherein said ridge has a length in a circumferential direction and said ridge includes a portion curving towards the exclusion edge and a portion curving away from the exclusion edge along the length of said ridge. 28. The hydrodynamic rotary seal of claim 23, wherein said ridge flank is located between and adjoining the lubricant side flank and the dynamic sealing surface. 29. A hydrodynamic rotary seal having an annular seal body having first and second body ends, a static sealing surface and an annular dynamic sealing lip in compressed contacting relationship with a relatively rotatable surface having a direction of relative rotation and defining an interfacial contact footprint therebetween, wherein the contact footprint has a substantially circular edge and a wavy edge including at least one wave having a wave height, the contact footprint has a minimum footprint width and a maximum footprint width between the circular edge and the wavy edge,wherein a swept zone is defined by the portion of the contact footprint circumferentially aligned with the wave height and an unswept zone is defined by the portion of the contact footprint circumferentially aligned with the minimum footprint width,wherein the dynamic sealing lip having a dynamic sealing surface located between the first and second body ends and terminating at an abrupt generally circular exclusion edge, a sloping inlet surface having a convex shape when viewed in longitudinal cross-section and located between the first body end and the dynamic sealing surface, a lubricant side flank having at least a portion thereof located between the first body end and the sloping inlet surface, the sloping inlet surface providing a transition between at least a portion of the lubricant side flank and at least a portion of the dynamic sealing surface, at least part of the sloping inlet surface being skewed with respect to the direction of relative rotation and forming at least part of a hydrodynamic inlet where the dynamic sealing lip gradually converges into contact with the relatively rotatable surface, the hydrodynamic inlet introducing a lubricant into the contact footprint in response to the relative rotation between the dynamic sealing lip and the relatively rotatable surface,wherein the improvement comprises: the dynamic sealing lip including a ridge flank having a boundary, at least a first portion of said ridge flank boundary at an intersection of said ridge flank and the sloping inlet surface and at least a second portion of said ridge flank boundary at an intersection of said ridge flank and the dynamic sealing surface, said at least the first portion of said ridge flank boundary comprising a first ridge portion defining an external corner when viewed in longitudinal cross-section, said at least the second portion of said ridge flank boundary comprising a second ridge portion defining an external corner when viewed in longitudinal cross-section, a ridge comprising said first and second ridge portions, said ridge producing a diverting pressure ridge within the contact footprint and diverting at least a portion of the lubricant from the swept zone into the unswept zone and toward the exclusion edge in response to the relative rotation between the dynamic sealing lip and the relatively rotatable surface;said ridge having a length and being curved in the circumferential direction so that some of said ridge is farther from the generally circular exclusion edge compared to a part of said ridge which is closer to the generally circular exclusion edge, there being an axial separating distance between said ridge and the exclusion edge;at least a portion of said diverting pressure ridge being located in the swept zone and skewed with respect to the direction of relative rotation. 30. The hydrodynamic rotary seal of claim 29, wherein said ridge is abrupt in an axial direction and becomes less abrupt along the length of said ridge as said ridge comes closer to the exclusion edge. 31. The hydrodynamic rotary seal of claim 29, wherein said ridge in an axial direction has a rounded character that varies in curvature along the length of said ridge. 32. The hydrodynamic rotary seal of claim 29, wherein said ridge flank is located between and adjoining the lubricant side flank and the dynamic sealing surface. 33. The hydrodynamic rotary seal of claim 29, wherein said ridge flank producing a visual appearance of cutting away a portion of the sloping inlet surface and a portion of the dynamic sealing surface. 34. The hydrodynamic rotary seal of claim 29, wherein at least a portion of said ridge flank is recessed relative to the sloping inlet surface and relative to the dynamic sealing surface. 35. The hydrodynamic rotary seal of claim 29, wherein the dynamic lip having a visual appearance, said visual appearance being that the sloping inlet surface and the dynamic sealing surface have a portion cut away by said ridge flank. 36. A hydrodynamic sealing assembly comprising: a first machine component defining a seal groove;a second machine component including a relatively rotatable surface having a direction of relative rotation; anda hydrodynamic seal in sealing engagement with said first and second machine components, said hydrodynamic seal comprising: a generally circular seal body having first and second body ends, an annular static sealing surface in sealing engagement with said seal groove, and an annular dynamic sealing lip in sealing engagement with said second machine component and deformed against said relatively rotatable surface and establishing an interfacial contact footprint therebetween;said contact footprint having a circular footprint edge and a wavy footprint edge including at least one wave having a wave height, said contact footprint having a minimum footprint width and a maximum footprint width between said circular footprint edge and said wavy footprint edge, a swept zone being defined by the portion of said contact footprint circumferentially aligned with the wave height and an unswept zone being defined by the portion of said contact footprint circumferentially aligned with said minimum footprint width,said dynamic sealing lip comprising an annular dynamic sealing surface located between said first and second body ends, a sloping inlet surface located between said first body end and at least a portion of said dynamic sealing surface, and a lubricant side flank located between said first body end and at least a portion of said sloping inlet surface, said sloping inlet surface having a convex profile when viewed in longitudinal cross-section and forming a smooth blended transition with at least part of said dynamic sealing surface, at least part of said sloping inlet surface being skewed with respect to the direction of relative rotation and forming part of a hydrodynamic inlet introducing a lubricant into said interfacial contact footprint in response to relative rotation,said dynamic sealing lip having a circular exclusion edge,a ridge flank bounded by a ridge flank boundary, at least a first portion of said ridge flank boundary comprising a first ridge portion at an intersection of said ridge flank and said sloping inlet surface, at least a second portion of said ridge flank boundary comprising a second ridge portion at an intersection of said ridge flank and said dynamic sealing surface, said first ridge portion defining an external corner when viewed in longitudinal cross-section and said second ridge portion defining an external corner when viewed in longitudinal cross-section, said ridge flank truncating at least a portion of said sloping inlet surface and at least a portion of said dynamic sealing surface,a ridge comprising said first and second ridge portions, said ridge producing a diverting pressure ridge within said interfacial contact footprint and diverting at least a portion of the lubricant from said swept zone into said unswept zone and toward said exclusion edge during relative rotation between said relatively rotatable surface and said hydrodynamic seal, at least a portion of said diverting pressure ridge being located in said swept zone and skewed with respect to said direction of relative rotation,said ridge being curved with respect to the direction of relative rotation so that some of said ridge is farther from said exclusion edge compared to a part of said ridge which is closer to said exclusion edge, there being an axial separating distance between said ridge and said exclusion edge, at least a portion of said dynamic sealing surface being located between said sloping inlet surface and said second body end and being located between said lubricant side flank and said second body end. 37. The hydrodynamic sealing assembly of claim 36, wherein said seal groove of said first machine component comprises first and second walls in opposing relationship and said hydrodynamic seal concurrently contacts said first and second walls. 38. The hydrodynamic sealing assembly of claim 36, wherein said ridge flank is located between said lubricant side flank and said dynamic sealing surface. 39. The hydrodynamic sealing assembly of claim 36, wherein said ridge flank is located between and adjoining said lubricant side flank and said dynamic sealing surface. 40. A hydrodynamic rotary seal for location by a machine component for dynamic sealing engagement with a relatively rotatable surface having a direction of relative rotation with respect to the rotary seal, and for serving as a partition between a first fluid of a lubricant supply and a second fluid, comprising: an annular static sealing surface forming a sealing interface with the machine component;a generally circular dynamic lip having a generally circular exclusion edge, at least a portion of said dynamic lip maintained in a compressed, contacting relation with the relatively rotatable surface to define an interfacial contact footprint between said dynamic lip and the relatively rotatable surface, a first footprint edge of said interfacial contact footprint being wavy, and a second footprint edge being generally circular, said first footprint edge having at least one wave having a wave height, said interfacial contact footprint having a minimum footprint width and a maximum footprint width between said first and second footprint edges, a swept zone being defined by the portion of said contact footprint circumferentially aligned with said wave height and an unswept zone being defined by the portion of said contact footprint circumferentially aligned with said minimum footprint width, said at least one wave having a wave leading edge and a wave trailing edge relative to said direction of relative rotation, said wave leading and trailing edges having skew relative to said direction of relative rotation, said skew of said leading edge being generally opposite said skew of said trailing edge,wherein during relative rotation between said dynamic lip and the relatively rotatable surface, said interfacial contact footprint is a dynamic sealing interface with sliding occurring between said dynamic lip and the relatively rotatable surface, and in the absence of relative rotation, said interfacial contact footprint is a static sealing interface;said dynamic lip comprising: an annular dynamic sealing surface contacting the relatively rotatable surface;a lubricant side flank facing the first fluid, at least part of said lubricant side flank being wavy, at least a portion of said dynamic sealing surface being located in intermediate relation to said lubricant side flank and said exclusion edge;a sloping inlet surface having a convex profile when viewed in longitudinal cross-section and blending at least a portion of said lubricant side flank to at least a portion of said dynamic sealing surface, at least a portion of said sloping inlet surface being skewed with respect to the direction of relative rotation and forming part of a hydrodynamic inlet for the first fluid, at least a portion of said dynamic sealing surface being located between said sloping inlet surface and said exclusion edge;a ridge flank bounded by a boundary, a first portion of said boundary at an intersection of said ridge flank with at least a portion of said sloping inlet surface producing an external corner, a second portion of said boundary at an intersection of said ridge flank and at least a portion of said dynamic sealing surface producing an external corner, a third portion of said boundary at an intersection of said ridge flank and at least a portion of said lubricant side flank producing an external corner, said at least a portion of said sloping inlet surface and said at least a portion of said dynamic sealing surface being truncated by said ridge flank, a ridge comprising said first and second portions of said boundary, each said external corner of said first and second portions of said boundary having a convex shape when viewed in longitudinal cross-section;at least part of said ridge being curved in a circumferential direction so that some of said ridge is farther from said exclusion edge compared to a part of said ridge which is closer to said exclusion edge, there being an axial separating distance between said ridge and said exclusion edge;said ridge having a ridge leading edge and a ridge trailing edge relative to said direction of relative rotation, said ridge leading edge being skewed relative to said direction of relative rotation and being skewed generally oppositely to said skew of said wave leading edge, at least a portion of said ridge being located in said swept zone and producing a diverting pressure ridge in said swept zone. 41. The hydrodynamic rotary seal of claim 40, wherein said ridge flank is located between said lubricant side flank and said dynamic sealing surface. 42. The hydrodynamic rotary seal of claim 40, wherein said ridge flank is located between and adjoining said lubricant side flank and said dynamic sealing surface. 43. The hydrodynamic rotary seal of claim 40, wherein said ridge flank producing a visual appearance of cutting away a portion of said sloping inlet surface and a portion of said dynamic surface. 44. The hydrodynamic rotary seal of claim 40, wherein said ridge flank has a visual appearance, said visual appearance being that of cutting away a portion of said sloping inlet surface and a portion of said dynamic surface. 45. The hydrodynamic rotary seal of claim 40, wherein at least a portion of said ridge flank is recessed relative to said sloping inlet surface and relative to said dynamic surface. 46. The hydrodynamic rotary seal of claim 40, wherein said dynamic lip having a visual appearance, said visual appearance being that said sloping inlet surface and said dynamic surface have a portion cut away by said ridge flank. 47. A hydrodynamic seal comprising: an annular seal body having first and second body ends, an annular static sealing surface and an annular dynamic sealing lip, said dynamic sealing lip including a lubricant side flank and a dynamic sealing surface adjoining a sloping inlet surface having a convex profile when viewed in longitudinal cross-section, said sloping inlet surface having a leading edge and a trailing edge, said leading edge of said sloping inlet surface having skew relative to said second body end;wherein at least a portion of said dynamic sealing lip defines a ridge flank surrounded by a boundary, at least a portion of said ridge flank boundary comprising a ridge at an intersection of said ridge flank and said sloping inlet surface, said ridge defining an external corner, said ridge having a leading edge and a trailing edge, said leading edge of said ridge having skew relative to said second body end, said skew of said leading edge of said ridge being generally opposite said skew of said leading edge of said sloping inlet surface;at least part of said ridge leading edge having the shape of an external corner when viewed in longitudinal cross-section,at least a portion of said ridge flank recessed relative to said sloping inlet surface, said at least a portion of said ridge flank intersecting said lubricant side flank at a second portion of said ridge flank boundary, at least part of said second portion of said ridge flank boundary defining an external corner;at least a portion of said sloping inlet surface being truncated by said ridge flank and said ridge;at least part of said ridge being curved so that some of said ridge is farther from said second body end compared to a part of said ridge which is closer to said second body end, there being a separating distance between said ridge and said second body end. 48. The hydrodynamic seal of claim 47, wherein said sloping inlet surface having a smooth blended transition with said dynamic sealing surface and with said lubricant side flank. 49. The hydrodynamic seal of claim 47, wherein at least a portion of said ridge is rounded and varies in curvature along at least part of the length thereof. 50. The hydrodynamic seal of claim 47, wherein said ridge interrupts said dynamic sealing surface. 51. The hydrodynamic seal of claim 47, wherein said ridge is defined by a sharp intersection. 52. The hydrodynamic seal of claim 47, wherein said ridge is defined by a rounded intersection. 53. The hydrodynamic seal of claim 47, wherein said seal body includes a flexible transitional heel located between said dynamic sealing surface and said second end of said seal body and sloped with respect to said dynamic sealing surface and said second end of said seal body, and said dynamic sealing surface terminating at said flexible transitional heel, an intersection between said dynamic sealing surface and said flexible transitional heel forming an abrupt exclusion edge of generally circular form. 54. The hydrodynamic seal of claim 53, wherein a heel transition is located between said flexible transitional heel and said second end of said seal body, and said heel transition is rounded when viewed in longitudinal cross-section. 55. The hydrodynamic seal of claim 53, wherein said ridge flank is shaped so that the distance between said ridge and said exclusion edge varies circumferentially, said ridge having a central portion and two end portions with said central portion located closer to said exclusion edge than said two end portions. 56. The hydrodynamic seal of claim 53, wherein the abruptness of said ridge varies as a function of its distance from said exclusion edge with the abruptness decreasing as said ridge nears said exclusion edge. 57. The hydrodynamic seal of claim 47, wherein said seal body includes an exclusion edge formed by an intersection between an end of said dynamic sealing surface and said second end of said seal body. 58. The hydrodynamic seal of claim 47, wherein said lubricant side flank is wavy and varies in slope around the circumference of said seal body. 59. The hydrodynamic seal of claim 47, wherein at least a portion of said sloping inlet surface is wavy in a radial and axial direction. 60. The hydrodynamic seal of claim 47, configured for use within a machine assembly, said machine assembly comprising: a first machine component defining a seal groove; anda second machine component having a relatively rotatable surface;wherein said seal body is in sealing engagement with said first and second machine components. 61. The hydrodynamic rotary seal of claim 47, wherein said ridge flank is located between said lubricant side flank and said dynamic sealing surface. 62. The hydrodynamic rotary seal of claim 47, wherein said ridge flank is located between and adjoining said lubricant side flank and said dynamic sealing surface. 63. The hydrodynamic rotary seal of claim 47, wherein said ridge flank producing a visual appearance of cutting away a portion of said sloping inlet surface. 64. The hydrodynamic rotary seal of claim 47, wherein said ridge flank has a visual appearance, said visual appearance being that of cutting away a portion of said sloping inlet surface. 65. The hydrodynamic rotary seal of claim 47, wherein said dynamic lip has a visual appearance, said visual appearance being that said sloping inlet surface has a portion cut away by said ridge flank. 66. The hydrodynamic rotary seal of claim 47, wherein said ridge flank is a peripheral shape tapering to a point at each end in a circumferential direction. 67. The hydrodynamic rotary seal of claim 47, wherein said ridge flank is a peripheral shape with first and second circumferential extremities, and tapers to a point at each of said first and second circumferential extremities. 68. The hydrodynamic rotary seal of claim 47, wherein said ridge flank has a circumferentially elongated peripheral shape having first and second circumferential extremities, and tapers to a first circumferentially oriented point at said first circumferential extremity and tapers to a second circumferentially oriented point at said second circumferential extremity, said first circumferentially oriented point facing in a generally opposite direction from said second circumferentially oriented point. 69. The hydrodynamic rotary seal of claim 47, wherein said ridge flank having an oval shape with first and second circumferential extremities, and tapers to a first circumferentially oriented point at said first circumferential extremity. 70. A hydrodynamic sealing assembly comprising: a first machine component defining a seal groove;a second machine component having a relatively rotatable surface; anda hydrodynamic seal in sealing engagement with said first and second machine components, said hydrodynamic seal comprising: an annular seal body having first and second body ends and a dynamic sealing lip, said dynamic sealing lip including an annular dynamic sealing surface adjoining a sloping inlet surface, said sloping inlet surface having a convex profile when viewed in longitudinal cross-section and providing a smooth blended transition to at least part of said dynamic sealing surface, and said dynamic sealing surface contacting said relatively rotatable surface;said sloping inlet surface having a leading edge and a trailing edge, said leading and trailing edges of said sloping inlet surface having skew relative to said second body end, said skew of said leading edge of said sloping inlet surface being generally opposite said skew of said trailing edge of said sloping inlet surface;said dynamic sealing lip including a ridge flank defining a ridge in the form of an external corner, said ridge serving as a bi-directional diverter, at least a first portion of said ridge in the form of an external corner at an intersection of said ridge flank and said dynamic sealing surface and at least a second portion of said ridge in the form of an external corner at an intersection of said ridge flank and said sloping inlet surface;said ridge having a leading edge and a trailing edge, said leading and trailing edges of said ridge having skew relative to said second body end, said skew of said leading edge of said ridge being generally opposite said skew of said leading edge of said sloping inlet surface;at least a portion of said sloping inlet surface being truncated by said ridge flank and said ridge;at least part of said ridge being curved, causing parts of said ridge to be farther from the second body end, compared to a part of said ridge which is closest to said second body end but separated from said second body end by a separating distance. 71. The hydrodynamic sealing assembly of claim 70, wherein said sloping inlet surface forms at least a part of a hydrodynamic inlet when said dynamic sealing lip contacts said relatively rotatable surface. 72. The hydrodynamic sealing assembly of claim 70, wherein said seal body is positioned substantially inside said seal groove. 73. The hydrodynamic sealing assembly of claim 70, wherein said seal groove of said first machine component is formed by first and second walls in opposing spaced relationship and said hydrodynamic seal concurrently contacts said first and second walls. 74. The hydrodynamic sealing assembly of claim 70, wherein said ridge flank producing a visual appearance of cutting away a portion of said sloping inlet surface. 75. The hydrodynamic sealing assembly of claim 70, wherein said ridge flank has a visual appearance, said visual appearance being that of cutting away a portion of said sloping inlet surface. 76. The hydrodynamic sealing assembly of claim 70, wherein at least a portion of said ridge flank is recessed relative to said sloping inlet surface. 77. The hydrodynamic sealing assembly of claim 70, wherein said dynamic lip has a visual appearance, said visual appearance being that said sloping inlet surface has a portion cut away by said ridge flank. 78. A hydrodynamic rotary seal comprising: an annular member having first and second ends generally facing in opposite axial directions and inner and outer surfaces generally facing opposite radial directions;said inner surface comprising: a wavy lubricant side flank located in intermediate relation to said member first and second ends and located spatially from said member second end, at least a portion of said lubricant side flank skewed relative to said member second end;a generally inwardly-facing annular dynamic sealing surface located in intermediate relation to said lubricant side flank and said member second end and terminating at an abrupt exclusion edge of generally circular form that is located spatially from said member first end and proximate said member second end, said dynamic sealing surface being radially inward of said lubricant side flank;a sloping inlet surface adapted for forming part of a hydrodynamic inlet upon installation of the rotary seal, said sloping inlet surface located between at least part of said lubricant side flank and at least part of said dynamic sealing surface, when viewed in longitudinal cross-section said sloping inlet surface has a convex curved form providing a smooth blended axial transition with said lubricant side flank and a smooth blended axial transition with said dynamic sealing surface, said sloping inlet surface having leading and trailing edges, at least a portion of said leading edge of said sloping inlet surface having skew with respect to said abrupt exclusion edge;a ridge flank located in intermediate relation to said member first end and said abrupt exclusion edge and located spatially from said abrupt exclusion edge, said ridge flank bounded by a peripheral boundary, at least a first portion of said ridge flank peripheral boundary defined at an intersection of said ridge flank with said sloping inlet surface, at least a second portion of said ridge flank peripheral boundary defined at an intersection of said ridge flank with said lubricant side flank, said at least a second portion of said ridge flank peripheral boundary comprising an external corner when viewed in longitudinal cross-section, and at least a third portion of said ridge flank peripheral boundary defined by a ridge formed at an intersection of said ridge flank with said dynamic sealing surface, said ridge defining an external corner and defining the most radially inward portion of said ridge flank when viewed in longitudinal cross-section, said ridge having leading and trailing edges, said leading edge of said ridge having skew with respect to said abrupt exclusion edge and with respect to said leading edge of said sloping inlet surface, said skew of said leading edge of said ridge being generally opposite said skew of said leading edge of said sloping inlet surface. 79. The hydrodynamic rotary seal of claim 78, wherein said ridge flank has a straight profile when viewed in longitudinal cross-section. 80. The hydrodynamic rotary seal of claim 78, wherein said ridge flank is angled relative to said dynamic sealing surface. 81. The hydrodynamic rotary seal of claim 78, wherein said ridge is nearer said exclusion edge than a remaining portion of said ridge flank when viewed in longitudinal cross-section. 82. The hydrodynamic rotary seal of claim 78, wherein said ridge flank is a peripheral shape tapering to a point at each end in a circumferential direction. 83. The hydrodynamic rotary seal of claim 78, wherein at least a portion of said ridge flank is radially outward of said sloping inlet surface. 84. The hydrodynamic rotary seal of claim 83, wherein at least a portion of said sloping inlet surface is radially outward of said ridge flank. 85. The hydrodynamic rotary seal of claim 78, wherein at least a portion of said ridge is axially located between said sloping inlet surface and said abrupt exclusion edge. 86. The hydrodynamic rotary seal of claim 78, wherein at least a portion of said ridge is axially located between said lubricant side flank and said dynamic sealing surface. 87. A ring-shaped hydrodynamic seal having a seal body of generally circular configuration and having a dynamic sealing lip of generally annular form that projects from the seal body, the seal body having a first body end and a second body end, the first body end located in generally opposed relation to the second body end, the dynamic sealing lip incorporating a dynamic sealing surface and having a lubricant side flank that is non-circular and wavy, the dynamic sealing lip having a widest part and narrower portions, the narrower portions of the dynamic sealing lip having a sloping inlet surface that is skewed with respect to a direction of relative rotation, at least part of the lubricant side flank being blended to the dynamic sealing surface by the sloping inlet surface, the dynamic sealing lip having an exclusion edge with an abrupt, circular form, the lubricant side flank located in spaced relation with respect to the exclusion edge and the second body end, wherein the improvement comprises: the dynamic sealing lip including a ridge flank having a boundary, at least a first portion of said ridge flank boundary at an intersection of said ridge flank and the sloping inlet surface and at least a second portion of said ridge flank boundary at an intersection of said ridge flank and the dynamic sealing surface, said at least the first portion of said ridge flank boundary comprising a first ridge portion in the form of an external corner and said at least the second portion of said ridge flank boundary comprising a second ridge portion in the form of an external corner, said first ridge portion and said ridge flank truncating at least part of the sloping inlet surface and said second ridge portion and said ridge flank truncating at least part of the dynamic sealing surface, thereby making the sloping inlet surface look as if a portion has been cut away, and thereby making the dynamic sealing surface look as if a portion has been cut away, a ridge comprising said first and second ridge portions, at least part of said ridge being curved so that some of said ridge is closer to the exclusion edge and some of said ridge is farther away from the exclusion edge. 88. The ring-shaped hydrodynamic seal of claim 87, wherein the sloping inlet surface is curved when viewed in longitudinal cross-section. 89. The ring-shaped hydrodynamic seal of claim 87, wherein said ridge and said ridge flank truncate at least a portion of the lubricant side flank, making the lubricant side flank look as if a portion has been cut away. 90. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion is sharp when viewed in longitudinal cross-section. 91. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion is rounded when viewed in longitudinal cross-section. 92. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion is rounded when viewed in longitudinal cross-section, and has a degree of abruptness that decreases as said first ridge portion comes closer to the exclusion edge. 93. The ring-shaped hydrodynamic seal of claim 87, wherein said ridge flank bifurcates the sloping inlet surface. 94. The ring-shaped hydrodynamic seal of claim 87, wherein an angle B is an included angle between the dynamic sealing surface and said ridge flank, and said angle B is greater than 90 degrees. 95. The ring-shaped hydrodynamic seal of claim 94, wherein said included angle B increases as said first ridge portion comes closer to the exclusion edge. 96. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion is rounded when viewed in longitudinal cross-section, having a local curvature that becomes larger as said first ridge portion comes closer to the exclusion edge. 97. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion has a length, and said first ridge portion is abrupt in an axial direction and becomes less abrupt along said length of said first ridge portion as said first ridge portion comes closer to the exclusion edge. 98. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion is abrupt with local curvature in an axial direction that varies in curvature as said first ridge portion comes closer to the exclusion edge. 99. The ring-shaped hydrodynamic seal of claim 87, wherein when viewed in longitudinal cross-section said ridge flank is substantially straight. 100. The ring-shaped hydrodynamic seal of claim 87, wherein said first ridge portion has a length in a circumferential direction, at least part of said first ridge portion is curved when viewed in longitudinal cross-section, and varies in axial position relative to the exclusion edge along said length of said first ridge portion. 101. The ring-shaped hydrodynamic seal of claim 87, wherein said ridge flank has a circumferentially elongated peripheral shape having first and second circumferential extremities, and tapers to a first circumferentially oriented point at said first circumferential extremity and tapers to a second circumferentially oriented point at said second circumferential extremity, said first circumferentially oriented point facing in a generally opposite direction from said second circumferentially oriented point. 102. The ring-shaped hydrodynamic seal of claim 87, wherein said ridge flank having an oval shape with first and second circumferential extremities, and tapers to a first circumferentially oriented point at said first circumferential extremity. 103. The ring-shaped hydrodynamic seal of claim 87, wherein said ridge flank has peripheral shape that tapers to a point in a circumferential direction. 104. A ring-shaped hydrodynamic seal having a seal body of generally circular configuration and having a dynamic sealing lip of generally annular form that projects from the seal body, the seal body having a first body end and a second body end, the first body end located in generally opposed relation to the second body end, the dynamic sealing lip incorporating a dynamic sealing surface and having a lubricant side flank that is non-circular and wavy, the dynamic sealing lip having a widest part and first and second narrower portions, each of the first and second narrower portions of the dynamic sealing lip having a sloping inlet surface that is skewed with respect to a direction of relative rotation, at least part of the lubricant side flank being blended to the dynamic sealing surface by the sloping inlet surface, the dynamic sealing lip having an exclusion edge with an abrupt circular form, the lubricant side flank located in spaced relation with respect to the exclusion edge and the second body end, wherein the improvement comprises: a ridge flank bounded by a boundary, said ridge flank located circumferentially between the first and second narrower portions of the dynamic sealing lip, and located axially between the dynamic sealing surface and the lubricant side flank, a first portion of said boundary at an intersection of said ridge flank and the dynamic sealing surface producing an external corner, a second portion of said boundary at an intersection of said ridge flank and the first sloping inlet surface producing an external corner, a third portion of said boundary at an intersection of said ridge flank and the second sloping inlet surface producing an external corner, and a fourth portion of said boundary at an intersection of said ridge flank and the lubricant side flank producing an external corner. 105. The ring-shaped hydrodynamic seal of claim 104, wherein said external corner is a rounded corner.