(19)
(11)EP 2 212 594 B2

(12)NEW EUROPEAN PATENT SPECIFICATION
After opposition procedure

(45)Date of publication and mention of the opposition decision:
27.06.2018 Bulletin 2018/26

(45)Mention of the grant of the patent:
02.09.2015 Bulletin 2015/36

(21)Application number: 08851903.8

(22)Date of filing:  20.11.2008
(51)International Patent Classification (IPC): 
F16J 15/447(2006.01)
F16C 33/36(2006.01)
F16C 33/78(2006.01)
F16J 15/32(2016.01)
F16J 15/44(2006.01)
F16C 19/38(2006.01)
F16C 35/073(2006.01)
(86)International application number:
PCT/US2008/084120
(87)International publication number:
WO 2009/067575 (28.05.2009 Gazette  2009/22)

(54)

NON-CONTACT LABYRINTH SEAL ASSEMBLY AND METHOD OF CONSTRUCTION THEREOF

KONTAKTFREIE LABYRINTHDICHTUNGSANORDNUNG UND VERFAHREN ZU IHRER HERSTELLUNG

ENSEMBLE JOINT LABYRINTHE SANS CONTACT ET PROCÉDÉ DE CONSTRUCTION DE CELUI-CI


(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

(30)Priority: 20.11.2007 US 989190 P
19.11.2008 US 273995

(43)Date of publication of application:
04.08.2010 Bulletin 2010/31

(73)Proprietors:
  • Federal-Mogul Corporation
    Southfield, MI 48033 (US)
  • The Timken Company
    Canton, OH 44706-0930 (US)

(72)Inventors:
  • LATTIME, Scott, B.
    Stow OH 44224 (US)
  • BOROWSKI, Richard
    Canton OH 44718 (US)
  • BLACK, Alicia
    Maybee MI 48159 (US)
  • DILLON, Kevin, M.
    Waterford MI 48327 (US)
  • TRENTMAN, Roger
    Fort Jennings OH 45844 (US)
  • BRISTER, Stephen, E.
    North Canton OH 44720 (US)
  • MEADOWS, Carl, F.
    Doylestown OH 44230 (US)
  • HUPP, Brian, M.
    Canton OH 44706 (US)
  • TOTH, David, G.
    Canton OH 44720 (US)

(74)Representative: Becker Kurig Straus 
Patentanwälte Bavariastrasse 7
80336 München
80336 München (DE)


(56)References cited: : 
DE-A1- 10 358 876
JP-A- H0 320 175
JP-A- 2007 009 938
JP-A- 2007 177 815
JP-A- 2007 177 815
JP-U- H0 558 953
JP-A- 9 144 767
JP-A- H09 144 767
JP-A- 2007 009 938
JP-A- 2007 177 815
JP-U- 5 058 953
US-A1- 2003 184 021
  
      


    Description

    BACKGROUND OF THE INVENTION


    1. Technical Field



    [0001] This invention relates generally to seal assemblies, and more particularly to non-contact seal assemblies for roller bearings.

    2. Related Art



    [0002] It is known to provide seals for sealed, self-contained bearing assemblies with preset clearances and lubrication. Being preset and lubricated, these bearings can be fitted over an axle journal and within a housing to enable relative rotation between the axle and the housing. These bearings have experienced wide-spread use on axles of railway cars, but they are also used in other applications, such as for crane wheels, table rolls and shears, and even for the work rolls of rolling mills, for example. When used in railway car applications, the bearings are subjected to high levels of contaminants, such as moisture, dirt and debris. In order to maintain the useful life of the bearing, the contaminants must remain external to the oil side of the bearing. Accordingly, the seals in these bearings play a vital role in prolonging the useful life of the bearings.

    [0003] Seals for railway bearings are known to have an outer case configured for attachment to an outer race of the bearing and an elastomeric seal element bonded to the seal case. The seal element typically extends radially inwardly from the outer case adjacent an oil side of the bearing to a primary lip that bears against an axially extending surface of a wear ring located adjacent to the inner race of the bearing. The seal element sometimes include secondary lips configured axially outwardly adjacent an air side of the bearing to bear against a radially extending leg of the wear ring. To maintain sealing engagement between the primary lip and the wear ring, a garter spring is commonly used to encircle the primary lip to force it snugly against the wear ring. The secondary lip is typically maintained in contact with the wear ring under the bias of the elastomer material from which the seal element is constructed. With the primary lip being biased into engagement with the wear ring, the primary lip generally provides such an effective barrier to the egress of the lubricant from within the bearing along the wear ring, that it is known for the secondary lip to starve for lubrication and to overheat. This, can cause the secondary lip to harden, thereby diminishing the overall effectiveness of the seal. In addition, the friction generated by the primary and secondary seal lips against the wear ring impart a measure of resistance to rotation, which tends to cause undue wear to the seal, and further, requires additional energy to overcome, thereby diminishing the efficiencies of the engine powering the railcar.

    [0004] The seal of the present invention, among other things, including economic benefits realized from constructing various embodiments discussed herein, operates with considerably less torque than conventional seals of the type currently utilized with the bearings discussed above. Moreover, it provides a generally continuous width labyrinth passage from an air side of the seal to an oil side of the seal to prevent the ingress of contaminants.

    [0005] US2003/0184021A1 discloses a seal assembly with a labyrinth sealing function between two lips and an flange of a wear sleeve at the air side, and a seal element laying down against the wear sleeve at the oil side in the form of an axial collar portion. DE10358876 discloses a seal assembly according to the preamble of claim 1.

    SUMMARY OF THE INVENTION



    [0006] The invention is defined by a seal assembly according to claim 1 and a method according to claim 10. According to one aspect of the invention, a non-contact labyrinth seal assembly has an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of the assembly with a leg extending radially inwardly from the outer flange toward the central axis. A body is attached to the leg, wherein the body has a radially outward lip and a radially inward lip. The lips extend axially from the leg toward an air side of the assembly with the radially outward lip diverging outwardly from the central axis to provide a first annular channel between the lips and a second annular channel between the radially outward lip and the leg. The first annular channel faces axially toward the air side of the assembly and the second annular channel faces radially outwardly from the central axis. The assembly further has a sleeve with an axially extending cylindrical wall and an annular first flange extending radially outwardly from the wall. The first flange has an annular projection extending axially into the first annular channel to provide a non-contact labyrinth passage extending along a serpentine path between the lips and the annular projection.

    [0007] According to another aspect of the invention, a railway roller bearing non-contact labyrinth seal assembly includes an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of the assembly with a leg extending radially inwardly from the outer flange toward the central axis. A seal body is attached to the leg. The seal body has a radially outward lip and a radially inward lip extending axially from the leg and diverging from one another toward an air side of the assembly to provide a first annular channel between the lips and a second annular channel between the radially outward lip and the leg. The assembly further includes a sleeve having a cylindrical wall and an annular first flange extending radially outwardly from the wall. The first flange has an annular projection extending axially into the first annular channel between the lips and in non-contacting relation with the lips to provide a non-contact generally □-shaped labyrinth passage extending between the lips and the annular projection.

    [0008] According to yet another aspect of the invention, a railway roller bearing non-contact labyrinth seal assembly is provided. The seal assembly has an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of the assembly with a leg extending radially inwardly from the outer flange toward the central axis. Further, the assembly includes a sleeve having a cylindrical wall with an annular projection extending radially outwardly from the wall. Further, the assembly has a seal body attached to one of the leg or the projection, wherein the seal body extends toward and remains out of contact with the other of the leg or the lip to provide a non-contact labyrinth seal passage between an oil side of the seal assembly and an air side of the seal assembly.

    [0009] According to yet another aspect of the invention, a method of constructing a purlely non-contact labyrinth seal assembly is provided. The method includes forming an outer rigid carrier having a generally cylindrical outer flange extending axially relative to a central axis of the assembly with a leg extending radially inwardly from the outer flange toward the central axis. Further, forming a sleeve having cylindrical wall with an annular projection extending radially outwardly from the wall. Then, attaching a seal body to at least one of the leg and the projection and extending toward and remaining out of contact with the other of the leg and the projection to provide a non-contact labyrinth seal passage extending between an oil side of the seal assembly and an air side of the seal assembly.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0010] These and other aspects, features and advantages of the present invention will become more readily appreciated when considered in connection with the following detailed description of presently preferred embodiments and best mode, appended claims and accompanying drawings, in which:

    Figure 1 is a partial cross-sectional view of a shaft and roller bearing assembly having a non-contact labyrinth seal assembly constructed in accordance with one presently preferred embodiment of the invention;

    Figure 2 is an enlarged cross-sectional view of the non-contact labyrinth seal assembly of Figure 1;

    Figure 3 is a partial cross-sectional view of a shaft and roller bearing assembly with a non-contact labyrinth seal assembly constructed in accordance with another presently preferred embodiment of the invention;

    Figure 4 is a cross-sectional view of a bearing assembly with a non-contact labyrinth seal assembly constructed in accordance with yet another presently preferred aspect of the invention;

    Figure 4A is an enlarged cross-sectional view of the non-contact labyrinth seal assembly of Figure 4;

    Figure 4B is an enlarged cross-sectional view of a non-contact labyrinth seal assembly constructed in accordance with yet another presently preferred aspect of the invention; and

    Figure 4C is an enlarged cross-sectional view of a non-contact labyrinth seal assembly constructed in accordance with yet another presently preferred aspect of the invention.


    DETAILED DESCRIPTION OF PRESENTLY PREFERRED EMBODIMENTS



    [0011] Referring in more detail to the drawings, Figure 1 illustrates a self-contained, pre-lubricated and preset bearing assembly 10 disposed about a journal 12 of a shaft or axle 14 and within a housing 16 to provide relative rotation between the axle 14 and housing 16 about a central axis 17 of the shaft 14 and assembly 10. In the application shown, such as a railway bearing application, for example, the bearing assembly 10 has a single outer race 18 received in the housing and a pair of inner races 20 separated by a spacer 21 and being clamped between a backing ring 22 and an end cap 24, with a plurality of rollers 26 maintained between the inner races 20 and the outer race 18. The backing ring 22 and the end cap 24 each bear against spacer rings 28, sometimes referred to as seal wear rings, which in turn bear against the inner races 20. The bearing assembly 10 has a pair of purely non-contact labyrinth seal assemblies 30, illustrated in Figures 1 and 2 in accordance with one aspect of the invention, on opposite sides of the bearing assembly 10 to maintain the lubrication on an oil side 31 of the seal assemblies 30 and within bearing assembly 10 and to prevent the ingress of contamination from an air side 33 of the seal assemblies 30, such as dirt and debris, into the bearing assembly 10. Accordingly, the seal assemblies 30, having a completely non-contact labyrinth construction, as discussed in more detail hereafter, produce minimal friction in use, while effectively preventing the egress of lubrication and ingress of contamination, thus, enhancing the performance and prolonging the useful life of the bearing assembly 10.

    [0012] As best shown in Figure 2, each non-contact labyrinth seal assembly 30 has an outer rigid carrier 32, preferably constructed from metal, such as from steel in a stamping operation, with an elastomeric seal body 34 attached thereto, and a metal inner sleeve 36. The carrier 32 has a generally cylindrical outer flange 38 extending axially relative to the central axis 17 of the assembly 30 with an annular leg 40 extending radially inwardly from the outer flange 38 toward the central axis 17. The outer flange 38 extends axially to a free end 42 that is preferably configured for direct attachment to the outer race 18 of the bearing assembly 10, though it could be configured for attachment to the housing 16, or otherwise. The leg 40 has opposite oil and air sides 44, 45 corresponding to and facing the oil and air sides 31, 33 of the bearing assembly 10, respectively, that extend to a free end 46. One or both of the sides 44, 45 can be treated, if desired, to facilitate bonding of the seal body 34 thereto, such as in an etching or sand/bead blasting operation, for example.

    [0013] The elastomeric seal body 34 is attached to the leg 40, such as by using a suitable adhesive or by molding directly to the leg 40. The body 34 is shown here, by way of example and without limitation, as being molded about the free end 46 of the leg 40 in bonded relation to the leg 40 and substantially covering the air side 45 of the leg 40. The body 34 has a radially outward lip 48 and radially inward lip 50. The lips 48, 50 extend laterally from the leg 40 toward the air side 33 of the assembly 30. The radially outward lip 48 diverges from the inward lip 50 and outwardly from the central axis 17 to provide a first annular channel 54 between the lips 48, 50 and a second annular gutter, referred to hereafter as channel 56, between the radially outward lip 48 and the leg 40 of the carrier 32. Accordingly, the first annular channel 54 faces axially toward the air side 33 of the assembly 30 and the second annular channel 56 faces radially outwardly from the central axis 17, and acts to inhibit the ingress of contamination into the bearing assembly 10. The body also has an undulating surface 58 facing radially inwardly toward the central axis 17. The undulating surface 58 extends axially along an inner bottom surface of the body 34, and is shown here as being provided partially by the inward lip 50. The lip 50 has a radially inwardly facing surface 51 that diverges away from the axis 17 toward the air side 33 of the assembly 30, such that during relative movement between the carrier 32 and the inner sleeve 36, the surface 51 acts to repell the ingress of contamination into the bearing assemlby 10. The undulating surface 50 also has a plurality of radially inwardly facing surfaces 53 axially inwardly from the surface 51. The surfaces 53 diverge away from the axis 17 toward the oil side 31 of the assembly 30, such that during relative movement between the carrier 32 and the inner sleeve 36, the surfaces 53 act to repell the egress of lubrication from the bearing assemlby 10. The body 34 further includes an exclusion lip 60 extending axially from the leg 40 toward the air side 33 of the assembly 30. The exclusion lip 60 is located radially outwardly from and in partially overlapping relation to the second annular channel 56. In addition, the body 34 further includes a containment lip 61 extending axially toward the oil side 31 of the assembly 30. The containment lip 61 is shown here, by way of example and without limitation, as extending generally from the free end 46 of the leg 40 axially toward the oil side 31 of the assembly 30.

    [0014] The metal inner sleeve 36 is preferably constructed from steel in a stamping operation, though other metal materials and processes could be used. The inner sleeve 36 has an axially extending cylindrical wall 62 with an inner surface 64 configured for operable disposal about the shaft 14, and shown in Figure 1 and 2, by way of example and without limtation, as being received on the spacer rings 28. The inner sleeve 36 also has an outer surface 65 opposite the inner surface 64. The sleeve 36 has an annular wall, also referred to as flange, or lip 66 extending radially outwardly from the wall 62 to an exclusion flange 68. The exclusion flange 68 extends axially from the barrier 66 in a radially outwardly overlapping relation with the cylindrical wall 62 to a free end 69, wherein the wall 62 and the exclusion flange 68 are shown here as being substantially parallel to one another. The barrier 66 has an annular projection 70 extending axially between the cylindrical wall 62 and the exclusion flange 68, and is shown here as being upset in the material of the the sleeve 36, such that the projection 70 is plastically deformed in the barrier 66. The projection 70 is generally □-shaped, as shown in Figure 2, having an annular lower leg 72 spaced radially outward in overlapping relation with the cylindrical wall 62 to provide an annular pocket 74 between the projection 70 and the cylindrical wall 62. The projection 70 has an annular upper leg 76 diverging radially outwardly from the lower leg 72 toward the air side 33, wherein the upper leg 76 acts as a slinger to repell contamination radially ouwardly from the seal assembly 30. The upper leg 76 transitions to the exclusion flange 68 at a reverse folded portion 77. Accordingly, another annular pocket 78 is formed between the upper leg 76 and the exclusion flange 68, wherein the pocket 78 is radially outwardly aligned with the radially inward pocket 74. In addition, the sleeve 36 has a containment flange 80 extending radially outwardly from the cylindrical wall 62. The containment flange 80, in addition to maintaining the assembly 30 in an assembled state, assists in preventing lubrication within the bearing assembly 10 from escaping the oil side 31, while also acting to prevent the ingress of any contamination into the oil side 31.

    [0015] With the carrier 32 assembled to the outer race 18 and the sleeve 36 disposed about the axle 14, the bearing assembly 10 is maintained in a preset condition with the seal assembly 30 being maintained in a purely non-contact labyrinth seal configuration. Accordingly, the seal body 34 and its associated features remain in spaced relation from the sleeve 36. For example, when fully assembled, the annular projection 70 of the sleeve 36 extends axially into the first annular channel 54 to provide a non-contact labyrinth passage 82 that extends along a serpentine path between the respective radially outward and radially inward lips 48, 50 and the annular projection 70. Further, the radially inward lip 50 extends into the pocket 74 in non-contacting relation with the sleeve 36 to provide a non-contact labyrinth passage 83 extending in open communication from the labyrinth passage 82, wherein the labyrinth passage 83 extends over a generally U-shaped or serpentine path within the pocket 74. Further again, the undulating surface 58 of the seal body 34 extends axially in spaced relation from the outer surface 65 of the sleeve wall 62 to provide a non-contact labyrinth passage 84 extending axially in open communication from the labyrinth passage 83. In addition, the exclusion flange 68 of the sleeve 36 extends in radially outward overlapping relation with the second annular channel 56, wherein the exclusion flange 68 is spaced radially outwardly from the radially outward lip 48. At the same time, the exclusion lip 60 of the seal body 34 extends in spaced, overlapping relation with the free end 69 of the exclusion flange 68, with the exclusion lip 60 being shown as being spaced radially outwardly from the exclusion flange 68 to provide a gap, wherein the gap provides a generally horizontally extending, non-contact labyrinth passage 81 configured in open communication with the second annular channel 56. Accordingly, the gutter or channel 56 is able to contain contamination on the radially upward half section of the seal assembly 30 and drain or dispell the contamination through the labyrinth passage 81 on the radially downward half of the seal assembly 30 with the assistance of gravitational and centripal forces. Further yet, the containment flange 80 extends radially outwardly from the cylindrical wall 62 radially beyond at least a portion of the elastomeric body 34, shown here as extending radially beyond the undulating surface 58, while remaining axially spaced from the undulating surface 58 to maintain a non-contact labyrinth passage 85 extending from the labyrinth passage 84. The containment lip 61 extends axially toward the oil side 31 in radially outwardly overlapping relation with the containment flange 80. The containment lip 61 is spaced radially outwardly from the containment flange 80 to extend the non-contacting labyrinth passage 85 in open communication with the oil side 31 of the assembly 30. Accordingly, seal assembly 30 is configured to maintain an entirely non-contactconstruction, with the continuously extending labyrinth passages 81, 82, 83, 84, 85 providing minimal friction in use, while preventing the ingress of contamination and the egress of lubrication. As shown, the labyrinth passages 82, 83, 84, and 85 are provided having a generally or substantially constant width (W), such as between about 0.010-0.100", extending along the radially outward lip 48, the radially inward lip 50 and the undulating surface 58. It should be recognized that some variations in the width W along the labyrinth passages 82, 83, 84, 85 is contemplated, such as would inherently occur along the undulating surface 58, for example.

    [0016] In Figure 3, a self-contained, pre-lubricated and preset bearing assembly 110 is shown in accordance with another presently preferred construction, wherein the same reference numerals as used above, offset by a factor of 100, are used to identify similar features. The bearing assembly 110 is constructed generally same as the previously discussed bearing assembly 10, with a labyrinth seal assembly 130 operably coupled to the bearing assembly 110, thereby providing a completely non-contact labyrinth seal construction, however, rather than an inner sleeve 136 of the seal assembly 130 being mounted on a spacer ring, the inner sleeve 136 is configured to be mounted directly on an outer surface of a thrust rib 21 of an inner race 120. As such, the configuration of a carrier 132 of the seal assembly 130 is altered to accommodate the change in configuration of the inner sleeve 136. In the embodiment illustrated, the carrier 132 is generally L-shaped in cross-section, with a leg 140 of the carrier 132 depending directly radially inwardly from a cylindrical outer flange 138 of the assembly 110. Otherwise, the seal assembly 130 is the same as the previously discussed seal assembly 30, and thus, no further discussion is believed necessary.

    [0017] In Figure 4, a self-contained, pre-lubricated and preset bearing assembly 210 with a non-contact labyrinth seal assembly 230 constructed in accordance with another presently preferred embodiment is shown, wherein the same reference numerals as used above, offset by a factor of 200, are used to identify similar features. As best shown in Figure 4A, the seal assembly 230 has an outer rigid carrier 232, preferably constructed from metal, such as from steel in a stamping operation, a seal body 234 attached to the carrier 232, a metal inner sleeve 236, and an elastomeric seal body, referred to hereafter as elastomeric body or simply body 87, attached to the inner sleeve 236 to provide a unitary inner sleeve subassembly. The carrier 232 has a generally cylindrical outer flange 238 extending axially relative to a central axis 217 of the assembly 230 with a leg 240 extending radially inwardly from the outer flange 238 toward the central axis 217. The outer flange 238 extends axially to a free end 242 that is preferably configured for direct attachment an outer race of a bearing assembly, though it could be configured for attachment to other than the bearing assembly. The leg 240 has opposite oil and air sides 244, 245 facing an oil side 231 and air side 233, respectively, wherein the leg 240 extends to a free end 246.

    [0018] The elastomeric seal body 234 is attached to the free end 246 of the leg 240, and is configured generally the same as described above with regard to the seal body 34. Accordingly, the seal body has a pair of lips 248, 250, with the radially outward lip 248 diverging from the radially inward lip 250 and outwardly from the central axis 217 to provide a first annular channel 254 between the lips 248, 250 and a second annular channel 256 between the radially outward lip 248 and the leg 240 of the carrier 232. Further, the body also has an undulating surface 258 facing radially inwardly toward the central axis 217 and extending axially along an inner bottom surface of the body 234, and being provided in part by the inward lip 250. The body 234 further includes an exclusion lip 260 extending axially from the leg 240 toward the air side 233 of the assembly 230. The exclusion lip 260 is located radially outwardly from and in partially overlapping relation to the second annular channel 256. In addition, the body 234 further includes a containment lip 261 extending axially toward the oil side 231 of the assembly 230. The containment lip 261 is shown here, by way of example and without limitation, as extending generally from the free end 246 of the leg 240 in radially outward relation to the undulating surface 258.

    [0019] The metal inner sleeve 236 and the elastomeric body 87 are configured having a generally similar cross-sectional shape as the inner sleeve 36 discussed above. Accordingly, the inner sleeve 236 and the elastomeric body 87 subassembly cooperate with the outer metal carrier 232 and seal body 234 to provide a non-contact labyrinth seal assembly similarly as discussed above with regard to the seal assembly 30. However, the elastomeric body 87 negates the need for many of the progressive manufacturing processes used to form the aforementioned upset annular projection 70 and exclusion flange 68 of the carrier 32. The inner sleeve 236 is preferably constructed from steel, such as in a stamping operation, although other manufacturing processes are contemplated. The inner sleeve 236 has an axially extending cylindrical wall 262 with an inner surface 264 and an outer surface 265, with the inner surface 264 being configured for operable disposal about a shaft, inner race of a bearing, or, as illustrated, by way of example and without limitation, a spacer ring 228 (Figure 4). The sleeve 236 is generally U-shaped in axial cross-section, having an annular wall, also referred to as flange, barrier, projection or lip 266 extending radially outwardly from the cylindrical wall 262. In addition, the sleeve 236 has a containment flange 280 extending radially outwardly from the cylindrical wall 262. The containment flange 280 functions similarly as discussed above with regard to the containment flange 80.

    [0020] The elastomeric body 87 is preferably molded to the lip 266 of the inner sleeve 236, with the body 87 being formed from an elastomeric or polymeric material, although it could be otherwise attached, such as via an adhesive, for example. The elastomeric body 87 forms an exclusion flange 268 extending axially from the metal lip 266 in a radially outwardly overlapping relation with the cylindrical wall 262 to a free end 269, wherein the wall 262 and the exclusion flange 268 are shown here as being substantially parallel to one another. The body 87 has an annular projection 270 extending axially inwardly from the lip 266 between the cylindrical wall 262 and the exclusion flange 268. The projection 270 is generally nose shaped, having generally the same inside conour as that of the projection 70 discussed above. As such, the projection has an annular lower, radially inward inner surface 272 spaced radially outward in overlapping relation with the cylindrical wall 262 to provide an annular pocket 274 between the projection 270 and the cylindrical wall 262. The projection 270 has an annular upper, radially outward inner surface 276 diverging radially outwardly from the lower inner surface 272 toward the air side 233, wherein the upper inner surface 276 transitions to the exclusion flange 268 at a reverse molded portion 277. Accordingly, another annular pocket 278 is formed between the upper inner surface 276 and the exclusion flange 268, wherein the pocket 278 is radially outwardly aligned with the radially inward pocket 274.

    [0021] As shown in Figure 4, with the carrier 232 assembled to the outer race 218 and the sleeve 236 disposed about the axle 214, the bearing assembly 210 is maintained in a preset condition with the seal assembly 230 being maintained in a purely non-contact labyrinth seal configuration. Accordingly, the seal body 234 and its associated features remain in spaced relation from the sleeve 236 and the elastomeric body 87. For example, when fully assembled, the annular projection 270 of the elastomeric body 87 extends axially into the first annular channel 254 to provide a non-contact labyrinth passage 282 that extends along a serpentine path between the respective radially outward and radially inward lips 248, 250 and the annular projection 270. Further, the radially inward lip 250 extends into the pocket 274 in non-contacting relation with the sleeve 236 and the elastomeric body 87 to provide a non-contact labyrinth passage 283 extending in open communication from the labyrinth passage 282, wherein the labyrinth passage 283 extends over a generally U-shaped or serpentine path within the pocket 274. Further again, the undulating surface 258 of the seal body 234 extends axially in spaced relation from the outer surface 265 of the sleeve wall 262 to provide a non-contact labyrinth passage 284 extending axially in open communication from the labyrinth passage 283. In addition, the exclusion flange 268 of the elastomeric body 87 extends in radially outward overlapping relation with the second annular channel 256, wherein the exclusion flange 268 is spaced radially outwardly from the radially outward lip 248. At the same time, the exclusion lip 260 of the seal body 234 extends in spaced, overlapping relation with the free end 269 of the exclusion flange 268, with the exclusion lip 260 being shown as being spaced radially outwardly from the exclusion flange 268 to provide a gap, wherein the gap provides a generally horizontally extending, non-contact labyrinth passage 281 configured in open communication with the second annular channel 256. Further yet, the containment flange 280 extends radially outwardly from the cylindrical wall 262 radially beyond at least a portion of the elastomeric seal body 234, shown here as extending radially beyond the undulating surface 258, while remaining axially spaced from the undulating surface 258 to maintain a non-contact labyrinth passage 285 extending from the labyrinth passage 284. The containment lip 261 extends axially toward the oil side 231 in radially outwardly overlapping relation with the containment flange 280. The containment lip 261 is spaced radially outwardly from the containment flange 280 to extend the non-contacting labyrinth passage 285 in open communication with the oil side 231 of the assembly 230. Accordingly, seal assembly 230 is configured to maintain an entirely non-contact construction, with the continuously extending labyrinth passages 281, 282, 283, 284, 285 providing minimal friction in use, while preventing the ingress of contamination and the egress of lubrication. As shown, the labyrinth passages 282, 283, 284, and 285 are provided having a generally or substantially constant width (W) extending along the radially outward lip 248, the radially inward lip 250 and the undulating surface 258. It should be recognized that some variations in the width W along the labyrinth passages 282, 283, 284, 285 is contemplated, such as would inherently occur along the undulating surface 58, for example.

    [0022] In Figure 4B, a non-contact labyrinth seal assembly 330 constructed in accordance with another presently preferred embodiment is shown, wherein the same reference numerals as used above, offset by a factor of 300, are used to identify similar features. The seal assembly 330 is configured having generally the same shape in axial cross-section as the previous assemblies 30, 130, 230, and includes an outer rigid carrier 332, a seal body 334 attached to the carrier 332, and an inner sleeve 336. However, rather than the carrier 332 and the seal body 334 being constructed of separate materials, in accordance with one method of constructing the assembly, they are constructed in accordance with another method of constructing the assembly by forming the carrier 332 and the seal body 334 as a single piece of material, such as in a molding process, for example. Preferably, the carrier 332 and the seal body 334 are molded from a sufficiently rigid polymeric material to allow it to be attached or received in a housing, such as in an outer ring of a railway bearing assembly, for example. Further, the inner sleeve 336 is molded from a sufficiently rigid polymeric material to allow it to be received about a shaft.

    [0023] The carrier 332 has a generally cylindrical outer flange 338 extending axially relative to a central axis 317 with a leg 340 extending radially inwardly from the outer flange 338. The leg 340 has opposite oil and air sides 344, 345 facing an oil side 331 and air side 333.

    [0024] The seal body 334 has a pair of lips 348, 350 diverging from one another as described above to provide a first annular channel 354 between the lips 348, 350 and a second annular channel 356 between the radially outward lip 348 and the leg 340. Further, the body has an undulating surface 358 facing radially inwardly toward the central axis 317, and further includes an exclusion lip 360 and a containment lip 361 as described above with regard to the previous embodiments.

    [0025] The inner sleeve 336 has an axially extending cylindrical wall 362 with an inner surface 364 and an outer surface 365, with the inner surface 364 being configured for operable disposal about a shaft, inner race of a bearing, or a spacer ring. The sleeve 336 has a containment flange 380 extending radially outwardly from the cylindrical wall 362, wherein the containment flange 380 functions similarly as discussed above. The sleeve 336 further includes an exclusion flange 368 and an annular projection 370 extending axially inwardly between the cylindrical wall 362 and the exclusion flange 368. The projection 370 is generally nose shaped, having generally the same inside conour as that of the projection 270 discussed above. As such, the projection 370 has an annular lower, radially inward inner surface 372 spaced radially outward in overlapping relation with the cylindrical wall 362 to provide an annular pocket 374 between the projection 370 and the cylindrical wall 362. The projection 370 has an annular upper, radially outward inner surface 376 diverging radially outwardly from the lower inner surface 372 toward the air side 333, wherein the upper inner surface 376 transitions to the exclusion flange 368 at a reverse molded portion 377. Accordingly, another annular pocket 378 is formed between the upper inner surface 376 and the exclusion flange 368.

    [0026] When assembled, the annular projection 370 extends axially into the first annular channel 354 to provide a non-contact labyrinth passage 382 that extends along a serpentine path between the respective radially outward and radially inward lips 348, 350 and the annular projection 370. Further, the radially inward lip 350 extends into the pocket 374 in non-contacting relation to provide a non-contact labyrinth passage 383 extending in open communication from the labyrinth passage 382, wherein the labyrinth passage 383 extends over a generally U-shaped or serpentine path within the pocket 374. Further again, the undulating surface 358 extends axially in spaced relation from the outer surface 365 of the sleeve wall 362 to provide a non-contact labyrinth passage 384 extending axially in open communication from the labyrinth passage 383. In addition, the exclusion flange 368 extends in radially outward, spaced overlapping relation with the second annular channel 356 and the exclusion lip 360 extends in spaced, overlapping relation with the exclusion flange 368 to provide a gap, wherein the gap provides a generally horizontally extending, non-contact labyrinth passage 381 configured in open communication with the second annular channel 356. Further, as in the previous embodiments, the containment flange 380 extends radially outwardly from the cylindrical wall 362 beyond the undulating surface 358, while remaining axially spaced from the undulating surface 358 to maintain a non-contact labyrinth passage 385 extending in open communication from the labyrinth passage 384.

    [0027] In Figure 4C, a non-contact labyrinth seal assembly 430 constructed in accordance with another presently preferred embodiment is shown, wherein the same reference numerals as used above, offset by a factor of 400, are used to identify similar features. The seal assembly 430 is configured having generally the same shape in axial cross-section taken along an axis 417 as the previous assemblies 30, 130, 230, 330 and includes an outer rigid carrier 432, a seal body 434 attached to the carrier 432, an inner sleeve 436, and a polymeric body 487 attached to the inner sleeve 436. As with the assembly 330, the seal assembly 430 is molded of polymeric materials, however, rather than the carrier 432 and the seal body 434 being constructed of the same material, they are constructed in accordance with another method of constructing the assembly by molding the carrier 432 and the seal body 434 as separate pieces attached to one another, and thus, can be molded using different types of polymeric materials. Accordingly, the carrier 432 can be formed by molding it using one rigid polymeric material, while the seal body 434 can be formed by molding it using a second, elastic polymeric material, such as rubber, for example. Similarly, the inner sleeve 436 can be molded from a sufficiently rigid polymeric material to allow it to be received about a shaft, while the polymeric body 487 can be molded from a second, elastic polymeric material, such as rubber, for example.

    [0028] When assembled, as with the previous embodiments, labyrinth passages 482, 483, 484, and 485 are provided having a generally or substantially constant width (W) extending along a radially outward lip 448, a radially inward lip 450 and an undulating surface 458. Further, a non-contact labyrinth passage 481 is configured in open communication with an annular channel 456, which in turn, is in open communication with the labyrinth passage 482. Lastly, a lubricant, such as a grease 89 of suitable weight can be provided in the labyrinth passage 484 between the undulating surface 458 and the inner sleeve 436 to further inhibit the ingress of contamination and the egress of lubricant.

    [0029] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.


    Claims

    1. A non-contact labyrinth seal assembly (30), comprising:

    an outer rigid carrier (32) having a cylindrical outer flange (38) extending axially relative to a central axis of said assembly with a leg (40) extending radially inwardly from said outer flange (38) toward said central axis;

    a body (34) attached to said leg (40), said body having a radially outward lip (48) and radially inward lip (50), said lips extending axially from said leg toward an air side (33) of said assembly with said radially outward lip (48) diverging outwardly from said central axis to provide a first annular channel (54) between said lips (48, 50) and a second annular channel (56) between said radially outward lip (48) and said leg (40), said first annular channel (54) facing axially toward said air side and said second annular channel (56) facing radially outwardly from said central axis; and

    a sleeve (36) having an axially extending cylindrical wall (62) with an annular first flange extending radially outwardly from said wall (62),

    said first flange having an annular projection (70) extending axially into said first annular channel to provide a non-contact labyrinth passage between an oil side and said air side extending along a serpentine path between said lips and said annular projection; and

    wherein said body (34) and said lips are spaced in completely non-contacting relation from said sleeve (36)

    characterized in that

    said body has an undulating surface (58) facing radially inwardly towards said central axis, said undulating surface extending axially in spaced relation from an outer surface of said sleeve wall (62), and that

    said sleeve has a containment flange (80) extending radially outwardly from said wall radially beyond said undulating surface.


     
    2. The seal assembly of claim 1 wherein said labyrinth passage maintains a constant width between said lips (48, 50) and said annular projection (70).
     
    3. The seal assembly of claim 1 wherein said first flange has an upstanding wall with a constant width with said annular projection (70) being plastically deformed in said upstanding wall.
     
    4. The seal assembly of claim 1 wherein said labyrinth passage maintains a constant width between said lips (48, 50) and said annular projection (70), and between said undulating surface and said outer surface of said sleeve wall.
     
    5. The seal assembly of claim 1 wherein said sleeve has an exclusion flange extending axially from said first flange in radially outward overlapping relation with said second annular channel.
     
    6. The seal assembly of claim 5 wherein said body has an exclusion lip extending axially from said leg in overlapping, spaced relation with said exclusion flange.
     
    7. The seal assembly of claim 1 wherein said body has a containment lip extending axially toward an oil side of said assembly in radially overlapping relation with said containment flange.
     
    8. The seal assembly of claim 1 wherein said carrier and said body are formed as a single piece of the same material.
     
    9. The seal assembly of claim 8 wherein said sleeve and said annular projection are formed as a single piece of the same material.
     
    10. A method of constructing a purely non-contact labyrinth seal assembly according to any previous claim, comprising:

    forming an outer rigid carrier (32) having a generally cylindrical outer flange (38) extending axially relative to a central axis of the assembly with a leg (40) extending radially inwardly from the outer flange (38) toward the central axis;

    forming a sleeve (36) having a cylindrical wall with an annular projection (70) extending radially outwardly from the wall and having a containment flange (80) extending radially outwardly from said wall; and

    forming a body (34) on the leg and configuring the body to extend toward and remain completely out of contact with the projection to provide a non-contact labyrinth seal passage extending completely from an oil side (31) of the seal assembly to an air side (33) of the seal assembly.


     
    11. The method of claim 10 further includes the step of molding the body as one piece of material with the leg.
     


    Ansprüche

    1. Kontaktfreie Labyrinthdichtungsanordnung (30), umfassend:

    einen äußeren starren Träger (32) mit einem zylinderförmigen äußeren Flansch (38), der sich in Bezug auf eine Mittelachse der Anordnung in der Achsenrichtung erstreckt, wobei sich ein Schenkel (40) von dem äußeren Flansch (38) radial einwärts zu der Mittelachse erstreckt;

    einen Körper (34), der an dem Schenkel (40) angebracht ist, wobei der Körper eine radial auswärts gerichtete Lippe (48) und eine radial einwärts gerichtete Lippe (50) aufweist, wobei sich die Lippen in der Achsenrichtung von dem Schenkel zu einer Luftseite (33) der Anordnung erstrecken, wobei die radial auswärts gerichtete Lippe (48) von der Mittelachse nach außen hin abweicht, um einen ersten ringförmigen Kanal (54) zwischen den Lippen (48, 50) und einen zweiten ringförmigen Kanal (56) zwischen der radial auswärts gerichteten Lippe (48) und dem Schenkel (40) zu bilden, wobei der erste ringförmige Kanal (54) in der Achsenrichtung zu der Luftseite gewandt ist und der zweite ringförmige Kanal (56) von der Mittelachse radial nach außen hin gewandt ist; und

    eine Hülse (36), die eine in der Achsenrichtung verlaufende zylinderförmige Wand (62) umfasst, wobei sich ein ringförmiger erster Flansch von der Wand (62) radial auswärts gerichtet erstreckt,

    wobei der erste Flansch einen ringförmigen Vorsprung (70) aufweist, der sich in der Achsenrichtung in den ersten ringförmigen Kanal erstreckt, um zwischen einer Ölseite und der Luftseite einen kontaktfreien Labyrinthdurchgang bereitzustellen, der sich entlang eines gewundenen Pfads zwischen den Lippen und dem ringförmigen Vorsprung erstreckt; und

    wobei der Körper (34) und die Lippen in einer vollständig kontaktfreien Beziehung von der Hülse (36) beabstandet sind,

    dadurch gekennzeichnet, dass

    der Körper eine wellige Oberfläche (58) aufweist, die radial einwärts zu der Mittelachse gewandt ist, wobei sich die wellige Oberfläche in der Achsenrichtung in einer von einer Außenfläche der Hülsenwand (62) beabstandeten Beziehung erstreckt, und dass die Hülse einen Einschlussflansch (80) aufweist, der sich von der Wand radial auswärts gerichtet über die wellige Oberfläche hinaus erstreckt.


     
    2. Dichtungsanordnung nach Anspruch 1, wobei der Labyrinthdurchgang zwischen den Lippen (48, 50) und dem ringförmigen Vorsprung (70) eine konstante Breite beibehält.
     
    3. Dichtungsanordnung nach Anspruch 1, wobei der erste Flansch eine hochragende Wand mit einer konstanten Breite aufweist, wobei der ringförmige Vorsprung (70) in der hochragenden Wand plastisch verformt wird.
     
    4. Dichtungsanordnung nach Anspruch 1, wobei der Labyrinthdurchgang zwischen den Lippen (48, 50) und dem ringförmigen Vorsprung (70) und zwischen der welligen Oberfläche und der Außenfläche der Hülsenwand eine konstante Breite beibehält.
     
    5. Dichtungsanordnung nach Anspruch 1, wobei die Hülse einen Ausschlussflansch aufweist, der sich in der Achsenrichtung in einer radial auswärts gerichtet überlappenden Beziehung mit dem zweiten ringförmigen Kanal von dem ersten Flansch erstreckt.
     
    6. Dichtungsanordnung nach Anspruch 5, wobei der Körper eine Ausschlusslippe aufweist, die sich in der Achsenrichtung in einer überlappenden beabstandeten Beziehung mit dem Ausschlussflansch von dem Schenkel erstreckt.
     
    7. Dichtungsanordnung nach Anspruch 1, wobei der Körper eine Einschlusslippe aufweist, die sich in der Achsenrichtung in einer radial überlappenden Beziehung mit dem Einschlussflansch zu einer Ölseite der Anordnung hin erstreckt.
     
    8. Dichtungsanordnung nach Anspruch 1, wobei der Träger und der Körper als ein einzelnes Stück aus dem gleichen Material gebildet sind.
     
    9. Dichtungsanordnung nach Anspruch 8, wobei die Hülse und der ringförmige Vorsprung als ein einzelnes Stück aus dem gleichen Material gebildet sind.
     
    10. Verfahren zur Herstellung einer rein kontaktlosen Labyrinthdichtungsanordnung nach einem der vorhergehenden Ansprüche, umfassend:

    Bilden eines äußeren starren Trägers (32) mit einem im Allgemeinen zylinderförmigen äußeren Flansch (38), der sich in Bezug auf eine Mittelachse der Anordnung in der Achsenrichtung erstreckt, wobei sich ein Schenkel (40) von dem äußeren Flansch (38) radial einwärts zu der Mittelachse erstreckt;

    Bilden einer Hülse (36), die eine zylinderförmige Wand aufweist, wobei sich ein ringförmiger Vorsprung (70) von der Wand radial auswärts gerichtet erstreckt, und die einen Einschlussflansch (80) aufweist, der sich von der Wand radial auswärts erstreckt; und

    Bilden eines Körpers (34) an dem Schenkel und derartiges Ausbilden des Körpers, dass er sich zu dem Vorsprung hin erstreckt und damit vollständig außer Kontakt steht, um einen kontaktfreien Labyrinthdichtungsdurchgang bereitzustellen, der sich vollständig von einer Ölseite (31) der Dichtungsanordnung zu einer Luftseite (33) der Dichtungsanordnung erstreckt.


     
    11. Verfahren nach Anspruch 10, ferner umfassend den Schritt des Formens des Körpers als ein Materialstück mit dem Schenkel.
     


    Revendications

    1. Ensemble de joint labyrinthe sans contact (30) comprenant :

    un support rigide extérieur (32) comportant un rebord extérieur cylindrique (38) s'étendant axialement par rapport à un axe central dudit ensemble avec une jambe (40) s'étendant radialement vers l'intérieur à partir dudit rebord extérieur (38) vers ledit axe central ;

    un corps (34) relié à ladite jambe (40), ledit corps comportant une lèvre radialement extérieure (48) et une lèvre radialement intérieure (50), lesdites lèvres s'étendant axialement à partir de ladite jambe vers un côté air (33) dudit ensemble, ladite lèvre radialement extérieure (48) divergeant vers l'extérieur à partir dudit axe central pour fournir un premier canal annulaire (54) entre lesdites lèvres (48, 50) et un deuxième canal annulaire (56) entre ladite lèvre radialement extérieure (48) et ladite jambe (40), ledit tourné axialement vers ledit côté air, ledit premier canal annulaire (54) étant tourné axialement vers ledit côté air et ledit deuxième canal annulaire (56) étant tourné radialement vers l'extérieur à partir dudit axe central ; et

    un manchon (36) comportant une paroi cylindrique (62) s'étendant axialement, avec un premier rebord annulaire s'étendant radialement vers l'extérieur à partir de ladite paroi (62),

    ledit premier rebord comportant une saillie annulaire (70) s'étendant axialement dans ledit premier canal annulaire pour fournir un passage en labyrinthe sans contact entre un côté huile et ledit côté air, lequel s'étend le long d'un parcours en serpentin entre lesdites lèvres et ladite saillie annulaire ; et

    dans lequel ledit corps (34) et lesdites lèvres sont espacés dans une relation entièrement sans contact par rapport audit manchon (36),

    caractérisé en ce que

    ledit corps comporte une surface ondulée (58) tournée radialement vers l'intérieur vers ledit axe central, ladite surface ondulée s'étendant axialement dans une relation espacée par rapport à une surface extérieure de ladite paroi de manchon (62), et en ce que

    ledit manchon comporte un rebord de confinement (80) s'étendant radialement vers l'extérieur à partir de ladite paroi, radialement au-delà de ladite surface ondulée.


     
    2. Ensemble de joint selon la revendication 1, dans lequel ledit passage en labyrinthe maintient une largeur constante entre lesdites lèvres (48, 50) et ladite saillie annulaire (70).
     
    3. Ensemble de joint selon la revendication 1, dans lequel ledit rebord comporte une paroi verticale avec une largeur constante, ladite saillie annulaire (70) étant déformée plastiquement dans ladite paroi verticale.
     
    4. Ensemble de joint selon la revendication 1, dans lequel ledit passage en labyrinthe maintient une largeur constante entre lesdites lèvres (48, 50) et ladite saillie annulaire (70), et entre ladite surface ondulée et ladite surface extérieure de ladite paroi de manchon.
     
    5. Ensemble de joint selon la revendication 1, dans lequel ledit manchon comporte un rebord d'exclusion s'étendant axialement à partir dudit premier rebord, dans une relation superposée radialement extérieure avec ledit deuxième canal annulaire.
     
    6. Ensemble de joint selon la revendication 5, dans lequel ledit corps comporte une lèvre d'exclusion s'étendant axialement à partir de ladite jambe, dans une relation espacée superposée avec ledit rebord d'exclusion.
     
    7. Ensemble de joint selon la revendication 1, dans lequel ledit corps comporte une lèvre de confinement s'étendant axialement vers un côté huile dudit ensemble, dans une relation superposée radialement avec ledit rebord de confinement.
     
    8. Ensemble de joint selon la revendication 1, dans lequel ledit support et ledit corps sont formés comme une seule pièce du même matériau.
     
    9. Ensemble de joint selon la revendication 8, dans lequel ledit manchon et ladite saillie annulaire sont formés comme une seule pièce du même matériau.
     
    10. Procédé de construction d'un ensemble de joint labyrinthe entièrement sans contact selon l'une quelconque des revendications précédentes, comprenant :

    la formation d'un support rigide extérieur (32) comportant un rebord extérieur généralement cylindrique (38) s'étendant axialement par rapport à un axe central de l'ensemble, une jambe (40) s'étendant radialement vers l'intérieur à partir dudit rebord extérieur (38) vers l'axe central ;

    la formation d'un manchon (36) comportant une paroi cylindrique avec une saillie annulaire (70) s'étendant radialement vers l'extérieur à partir de la paroi et comportant un rebord de confinement (80) s'étendant radialement vers l'extérieur à partir dudit rebord ; et

    la formation d'un corps (34) sur la jambe et la configuration du corps de manière à ce qu'il s'étende vers la saillie tout en restant entièrement hors contact avec celle-ci, afin de fournir un passage de joint labyrinthe sans contact s'étendant entièrement d'un côté huile (31) de l'ensemble de joint jusqu'à un côté air (33) de l'ensemble de joint.


     
    11. Procédé selon la revendication 10, comprenant en outre l'étape de moulage du corps en une seule pièce de matériau avec la jambe.
     




    Drawing


























    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description