Patent Publication Number: US-2023160434-A1

Title: Transport securable axial seal assembly

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to seals, and more particularly to seals for wheel bearing assemblies. 
     Wheel bearing assemblies, particularly for mounting wheels to vehicles such as trucks, typically include an inner axle connected with a vehicle frame, an outer hub connectable to the wheel, and a bearing for rotatably coupling the hub with the axle. The bearings are often double-row tapered rollers disposed between the outer hub and the inner axle and enable the hub, and thereby the wheel, to rotate about a central axis extending through the fixed axle. As such bearings are generally exposed to contaminants such as brake dust, dirt, oil, metal shavings, etc., which may damage the bearings if contacting the rolling elements or the bearing raceway surfaces, one or more seals are provided adjacent to the raceways to exclude such contaminants. Such seal assemblies primarily function to retain lubricant, for example, oil, grease, etc., within the bearing. 
     SUMMARY OF THE INVENTION 
     In one aspect, the present invention is an axial seal assembly for sealing a bearing, the bearing coupling an inner shaft and an outer member, the outer member having an inner circumferential surface defining a bore and the shaft being disposed within the bore. The seal assembly comprises an inner annular shield having an axial portion disposeable about the shaft at a position adjacent to the bearing and a radial portion extending radially outwardly from the axial portion. An outer annular seal has an axial portion engageable with the outer member bore and a radial portion extending radially inwardly from the axial portion, the seal including at least one axial sealing lip engaged with the radial portion of the annular shield. The seal radial portion is spaced from the shield radial portion by at least a predetermined axial distance during use of the seal assembly. The seal has at least one coupler section engageable with the radial portion of the shield or with the axial portion of the shield when an axial spacing distance between the seal radial portion and the shield radial portion is less than the predetermined distance so as to retain the shield coupled with the seal when the seal assembly is separate from the shaft and the outer member. 
     In another aspect, the present invention is again an axial seal assembly for sealing a bearing, the bearing coupling an inner shaft and an outer member, the outer member having an inner circumferential surface defining a bore and the shaft being disposed within the bore. The seal assembly comprises an inner annular shield having an axial portion disposeable about the shaft at a position adjacent to the bearing and a radial portion extending radially outwardly from the axial portion. An outer annular seal has an axial portion engageable with the outer member bore and a radial portion extending radially inwardly from the axial portion, the seal including at least one axial sealing lip engaged with the radial portion of the annular shield. The seal radial portion is spaced from the shield radial portion by at least a predetermined axial distance during use of the seal assembly. The seal has an outer shoulder engageable with the radial portion of the shield or an inner shoulder engageable with the axial portion of the shield when an axial spacing distance between the seal radial portion and the shield radial portion is less than the predetermined distance. As such, the shield is coupled with the seal when the seal assembly is separate from the shaft and the outer member. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The foregoing summary, as well as the detailed description of the preferred embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, which are diagrammatic, embodiments that are presently preferred. It should be understood, however, that the present invention is not limited to the precise arrangements and instrumentalities shown. In the drawings: 
         FIG.  1    is an axial cross-sectional view of an upper portion of a wheel bearing assembly including two seal assemblies in accordance with a first construction; 
         FIG.  2    is an enlarged, axial cross-sectional view of an upper portion of the first construction seal assembly shown installed in an in-use configuration; 
         FIG.  3    is an enlarged, axial cross-sectional view of an upper portion of the first construction seal assembly shown as a coupled-together unit; 
         FIG.  4    is an axial cross-sectional view of an upper portion of the first construction seal assembly shown during a coupling process; 
         FIG.  5    is an axial cross-sectional view of an upper portion of the first construction seal assembly shown during a final installation step; 
         FIG.  6    is an enlarged, axial cross-sectional view of an upper portion of a second construction seal assembly shown installed in an in-use configuration; 
         FIG.  7    is an enlarged, axial cross-sectional view of an upper portion of the second construction seal assembly shown as a coupled-together unit; 
         FIG.  8    is an axial cross-sectional view of an upper portion of the second construction seal assembly shown during a coupling process; 
         FIG.  9    is an axial cross-sectional view of an upper portion of the second construction seal assembly shown during a final installation step; 
         FIG.  10    is an enlarged, axial cross-sectional view of an upper portion of a third construction seal assembly shown installed in an in-use configuration; 
         FIG.  11    is an enlarged, axial cross-sectional view of an upper portion of the third construction seal assembly shown as a coupled-together unit; 
         FIG.  12    is an axial cross-sectional view of an upper portion of the third construction seal assembly shown during a coupling process; and 
         FIG.  13    is an axial cross-sectional view of an upper portion of the third construction seal assembly shown during a final installation step. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Certain terminology is used in the following description for convenience only and is not limiting. The words “inner”, “inwardly” and “outer”, “outwardly” refer to directions toward and away from, respectively, a designated centerline or a geometric center of an element being described, the particular meaning being readily apparent from the context of the description. Further, as used herein, the words “connected” and “coupled” are each intended to include direct connections between two members without any other members interposed therebetween and indirect connections between members in which one or more other members are interposed therebetween. The terminology includes the words specifically mentioned above, derivatives thereof, and words of similar import. 
     Referring now to the drawings in detail, wherein like numbers are used to indicate like elements throughout, there is shown in  FIGS.  1 - 13    an axial seal assembly  10  for sealing a bearing  1 , the bearing  1  coupling an inner shaft  2  and an outer member  3 . The outer member  3  has an inner circumferential surface  3   a  defining a bore  4  and the shaft  2  is disposed within the bore  4 . Preferably, the outer member  3  is a hub and the bearing  1 , the shaft  2  and the outer member/hub  3  form a wheel bearing assembly  5 , most preferably for an electrically powered or “electric” truck, the outer member/hub  3  being rotatable about an axis Ac extending through the shaft  2  and configured to couple a wheel (not shown) with a vehicle (not shown). However, the seal assembly  10  may be used in any other appropriate application, such as to seal a bearing  1  for a pump, an electric motor, a turbine, a conveyor, etc. The seal assembly  10  has a centerline L C  collinear with the axis Ac and basically comprises an inner annular shield  12  coupleable with the shaft  2  and an outer annular seal  14  disposed about the shield  12  and coupleable with the outer member  3 , the seal  14  having at least one coupler section  15  coupleable with shield  12  to form a coupled-together seal unit  11  for transport and assembly. 
     More specifically, the inner annular shield  12  has an axial portion  16  disposeable about the shaft  2  at a position adjacent to the bearing  1 , as shown in  FIG.  1   , and a radial portion  18  extending radially outwardly from the axial portion  16 . The shield axial portion  16  has first and second axial ends  16   a,    16   b  and inner and outer circumferential surfaces  17 A,  17 B, the inner surface  17 A preferably being frictionally engageable with an outer surface  2   a  of the shaft  2  to couple the shield  12  thereto. The shield radial portion  18  has inner and outer radial ends  18   a,    18   b,  respectively, and opposing radial surfaces  19 A,  19 B, the inner radial end  18   a  being integrally formed with the first end  16   a  of the axial portion  16 . In certain constructions shown in  FIGS.  1 - 9   , the shield  12  further includes a flange  20  extending axially from the outer end  18   b  of the radial portion  18  in direction generally toward the seal  12 , as discussed below, the flange  20  having opposing axial ends  20   a,    20   b  and inner and outer circumferential surfaces  21 A,  21 B, respectively. 
     Further, the annular seal  14  has an axial portion  24  engageable with the outer member bore  3 , a radial portion  26  extending radially inwardly from the axial portion  24  and at least one and preferably at least two axial sealing lips  28  engaged with the radial portion  18  of the shield  12 . The seal axial portion  24  has first and second axial ends  24   a,    24   b,  respectively, and inner and outer circumferential surfaces  25 A,  25 B, respectively, the outer surface  25 B preferably being frictionally engageable with the outer member inner surface  3   a  to couple the seal  14  thereto. The seal radial portion  26  has outer and inner radial ends  26   a,    26   b,  respectively, and opposing radial surfaces  27 A,  27 B, the outer end  26   a  being integrally formed with the axial portion second end  24   b.  During use of the seal assembly  10 , the seal radial portion  26  is spaced from the shield radial portion  18  by at least a predetermined axial distance DP, as indicated in  FIGS.  2 ,  6  and  10   , so as to establish a desired contact pressure between the outer end  28   a  of each axial sealing lip  28  and the radial surface  19 A of the shield radial portion  18 , which establishes a “use configuration” of the seal assembly  10 . 
     Furthermore, the at least one seal coupler section  15  is engageable with the radial portion  18  of the shield  12  or with the axial portion  16  of the shield  12  when an axial spacing distance DS between the seal radial portion  26  and the shield radial portion  18  is less than the predetermined distance DP, i.e., DS&lt;DP. As such, the coupler section(s)  15  function to retain the shield  12  coupled with the seal  14  when the seal assembly  10  is separate from the outer member bore  4 , and thus from the wheel bearing assembly  5 , so as to form the coupled-together unit  11 . Also, the seal  14  and the shield  12  are installable within the outer member bore  4  as the coupled-together unit  11 , which is described below. Thereafter, the seal  14  is displaceable axially away from the shield  12 , by means of an installation tool T 3 , so that the spacing distance DS between the shield radial portion  18  and the seal radial portion  26  is about equal to the desired, predetermined axial distance DP, as discussed in further detail below. 
     Referring to  FIGS.  2 ,  3 ,  6 ,  7 ,  10  and  11   , the at least one coupler section  15  of the seal  14  is preferably provided by a projection or shoulder  30  projecting radially inwardly from the seal axial portion  24  and engageable with the shield radial portion  18 , as shown in  FIGS.  2  and  3   , or/and by a shoulder  32  projecting radially inwardly from the seal radial portion  28  and engageable with the shield axial portion  16 , as depicted in  FIGS.  6 ,  7 ,  10  and  11   . More specifically, in a first construction depicted in  FIGS.  1 - 5   , the seal axial portion  24  includes a radially inwardly extending, outer shoulder  30  having an inner circumferential surface  31  with an inside diameter ID SO  ( FIG.  4   ). In this construction, the shield  12  includes the flange  20  with the outer circumferential surface  21 B having an outside diameter OD F  ( FIG.  4   ) which is greater than the inside diameter ID SO  of the shoulder inner circumferential surface ID SO , i.e., OD F &gt;ID SO . As such, the seal shoulder inner circumferential surface  31  is frictionally engaged with the shield flange outer circumferential surface  21 B when the axial spacing distance DS is less than the predetermined distance DP so as to releasably couple the shield  12  and the seal  14 . 
     In second and third constructions shown in  FIGS.  6 - 13   , the seal radial portion  26  includes a radially inwardly extending, inner shoulder  32  having an inner circumferential surface  33  with an inside diameter ID SI . The outer circumferential surface  17 B of the shield axial portion  16  has an outside diameter OD A  greater than the inside diameter ID SI  of the seal shoulder inner circumferential surface  33 , i.e., OD A &gt;ID SI . With this structure, the seal shoulder inner circumferential surface  33  is frictionally engaged with the shield axial portion outer circumferential surface  17 B when the axial spacing distance DS is less than the predetermined distance DP to thereby releasably couple the shield  12  and the seal  14 . 
     Referring to  FIGS.  2 - 13   , the seal  14  is preferably a composite formed of a rigid base  40  and an annular elastomeric body  42  molded to the base  40 , although the seal  14  may alternatively be formed as a one-piece body fabricated of an elastomeric material or of any other appropriate material (no alternatives shown). Specifically, the annular rigid base  40  has L-shaped axial cross-sections and includes an axial section  44  providing part of the seal axial portion  24  and a radial section  46  extending radially inwardly from the axial section  44  and providing part of the seal radial portion  26 . The rigid body axial section  44  has opposing first and second axial ends  44   a,    44   b,  respectively, and inner and outer circumferential surfaces  45 A,  45 B and the rigid body radial section  46  has outer and inner radial ends  46   a,    46   b,  respectively, and opposing radial surfaces  47 A,  47 B, the radial section outer end  46   a  being integrally formed with the axial section second end  44   b.  Also, the axial section  44  of the rigid base  40  may be substantially axial as depicted in  FIGS.  2 - 8    or may include an axial segment and a frustoconical segment as shown in  FIGS.  9 - 13   . 
     Further, the elastomeric body  42  is disposed on the rigid base  40  and provides the one or more axial sealing lips  28  and the outer shoulder  30  or/and the inner shoulder  32 . As such, each shoulder  30  or  32  is elastomeric and is either annular and extends entirely about the centerline L C  ( FIG.  1   ) or includes/is formed of a plurality of arcuate segments (not shown) spaced circumferentially about the centerline L C . Specifically, in the first construction, the elastomeric body  42  includes the outer shoulder  30  extending radially inwardly from an axial section  42   a  of the elastomeric body  42  disposed on the inner circumferential surface  45 A of the base axial section  44 . The shoulder  30  is engageable with the shield radial portion  18 , specifically the outer surface  21 B of the flange  20 , when the spacing distance DS is less than the predetermined spacing distance DP, as indicated in  FIG.  3   . 
     Preferably, the outer shoulder  30  is spaced axially from the first axial end  44   a  of the base axial section  44  such that an annular clearance space S C  is defined between the first axial end  44   a  and the shoulder  30 . With this structure, the radial outer end  18   b  of the shield radial portion  18  is disposed within the annular clearance space S C  when the seal assembly  10  is in the “use configuration”, i.e., the axial spacing distance DS is about equal to the predetermined axial distance DP as depicted in  FIG.  2   . Further, when the first construction seal assembly  10  is arranged in the use configuration, an outer annular labyrinth gap LG AO  is defined between the shield flange  20  and the seal base axial section  44  and an outer axial labyrinth gap LG XO  is defined between the axial end  20   b  of the shield flange  20  and the shoulder  30 . Preferably, the elastomeric body  42  has an inner radial end  42   b  spaced radially outwardly from the shield axial portion  16  so as to define an inner annular labyrinth gap LG AI . 
     Referring now to  FIGS.  6 - 13   , in second and third constructions, the elastomeric body  42  includes the inner shoulder  32  extending radially inwardly from a section  42   b  of the elastomeric body  42  disposed on the base radial section  46 . The inner shoulder  32  is engageable with the shield axial portion  14 , specifically with the radial portion outer circumferential surface  15 B, when the spacing distance DS is less than the predetermined distance DP. Also, the shoulder  32  is spaced axially from the second axial end  16   b  of the shield axial portion  16  when the axial spacing distance DS is about equal to the predetermined axial distance DP. Further, when the seal assembly  10  is arranged in the use configuration, an inner axial labyrinth gap LG XI  is formed between the shoulder  32  of the seal  16  and the second axial end  16   b  of the shield axial portion  16  and in the second construction, an outer annular labyrinth gap LG AO  is defined between the shield flange  20  and the seal base axial section  44 . 
     Referring to  FIGS.  4 ,  5 ,  8 ,  9 ,  12  and  13   , to couple the shield  12  and the seal  14 , the two components  12 ,  14  are preferably disposed between a first tool T 1  and a second tool T 2 , and then an axial force F A1  is applied through the first tool T 1  to the shield  12 . The shield  12  is displaced axially toward the seal  14  so that the outer shoulder  30  engages with the shield flange  20  ( FIG.  4   ) or/and the inner shoulder  32  engages with the shield axial portion  16  ( FIGS.  8  and  12   ) and the shield and seal radial portions  18 ,  26  are spaced by a distance DS less than the predetermined distance DP, as shown in  FIGS.  4 ,  8  and  12   . Each coupled-together unit  11  may then be “transported”, e.g., moved within a manufacturing facility for installation into an outer member/hub  3 , shipped to a retailer or customer, etc., and then installed within a wheel bearing assembly  5  or within another appropriate application (e.g., a pump, an electric motor, a conveyor, a diagnostic machine, etc.). Preferably, each coupled-together unit  11  is then installed within the outer member  3  (i.e., wheel hub, pump housing, etc.) by first displacing the entire unit  11  axially into and partially within the bore  4 , for example by means of the tool T 1 , until the shield  12  is located proximal to a desired installation position adjacent to a bearing. Thereafter, the seal  14  is displaced axially away from the shield  12  by means of a third tool T 3  which engages only with the outer perimeter of the seal  14  (i.e., the seal axial portion  24 ) until the shield  12  and the seal  14  are spaced apart by the about the predetermined spacing distance DP, and preferably the first end  24   a  of the seal axial portion  24  is generally axially aligned or “flush” with the “outer” radial surface  19 B of the shield radial portion  18 , as shown in  FIGS.  5 ,  9  and  13   . The shaft  2  may then be inserted through the shield  12  to finalize the fabrication of the wheel bearing assembly  5  or other seal application. However, the seal assembly  10  may be installed within the wheel bearing assembly  5  or other application in any other appropriate manner, for example, by installing the coupled-together unit  11  about the shaft  2  and then within the outer member  3 . 
     Although the three depicted exemplary constructions of the present invention each only have one coupler section  15 , i.e., either the outer shoulder  30  or the inner shoulder  32 , the seal assembly  10  may be formed with both inner and outer shoulders  30 ,  32  or with three or more shoulders/coupler sections (no alternatives shown). Further, the coupler section  15  may be formed in any other appropriate manner capable of releasably coupling the shield  12  and the seal  14 , for example by providing a shoulder (not shown) on the shield  12  which is engageable with a portion of the seal  14 , etc. 
     Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. 
     Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings. 
     All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter. The invention is not restricted to the above-described embodiments, and may be varied within the scope of the following claims.