Abstract:
A multi-purpose gauge for inspecting a hub-piloted wheel assembly includes a first cylindrical section having a first diameter (d 1 ); a second cylindrical section having a second diameter (d 2 ); and a third cylindrical section having a third diameter (d 3 ). The third cylindrical section defines both an end of the gauge and a cylindrical bore having an inner diameter (id). The second cylindrical section is disposed between the first cylindrical section and the third cylindrical section. Additionally, the first diameter is smaller than the second diameter, which in turn is smaller than the third diameter; and the inner diameter is greater than the first diameter.

Description:
TECHNICAL FIELD 
     The present invention relates generally to an inspection gauge for a hub-pilot wheel system. 
     BACKGROUND 
     In commercial trucking applications, wheels may be properly aligned on a hub using either specially designed mounting hardware, or through the geometry of the hub itself. These two designs are respectively referred to as stud-piloted wheel mounting, and hub-piloted wheel mounting. In a stud-piloted wheel, the studs that are used to secure the wheel also serve to align the wheel on the hub. In this design, ball-seat cap nuts fit into chamfered ball-seats provided in the bolt-hole openings of the wheel to position the wheel. In a dual wheel hub, additional hardware is required to properly position both the inner and outer wheel. More specifically, a ball-seat inner barrel nut between the wheels serves as both a nut for the inner wheel, and a stud for the outer wheel. 
     Hub-piloted, also known as “unimount” disc wheels are designed to center on the hub at the center hole or bore of the wheel. The wheel center hole locates the wheel on pilots built into the hub. Hub-piloted wheels are used with flange nuts which flushly contact the flat wheel disc face around the bolt-hole. Only one nut on each stud is used to fasten single or dual wheels to a vehicle. Hub-piloted wheels have straight through bolt-holes with no ball seat. 
     Ensuring that a wheel is properly secured to the hub is of critical importance. This requires that each nut be properly torqued onto the stud within a narrow tolerance range. Over tightening the nut may result in damage to the stud, such as compromised threads, plastic deformation of the stud, or ultimate failure/sheering. Likewise, under tightening the nut may result in wheel movement or “indexing,” with the nut eventually backing off and the wheel becoming unsecured. 
     SUMMARY 
     A multi-purpose gauge for inspecting a hub-piloted wheel assembly includes a first cylindrical section having a first diameter (d 1 ); a second cylindrical section having a second diameter (d 2 ); and a third cylindrical section having a third diameter (d 3 ). The third cylindrical section defines both an end of the gauge and a cylindrical bore having an inner diameter (id). The second cylindrical section is disposed between the first cylindrical section and the third cylindrical section. Additionally, the first diameter is smaller than the second diameter, which in turn is smaller than the third diameter; and the inner diameter is greater than the first diameter. 
     In one configuration, a quick disconnect feature may be disposed in selective communication with the first cylindrical section. This may allow a technician to removably attach the gauge from, for example, a key ring. 
     When intended for use with heavy-duty trucks, such as those that use M22×1.5 sized wheel studs, d 1  may be from about 20.676 mm to about 20.727 mm; d 2  may be from about 25.883 mm to about 25.984 mm; d 3  may be from about 26.988 mm to about 27.026 mm; and id may be from about 21.694 mm to about 21.732 mm. The gauge may further include an indicia provided in an outer surface of the first cylindrical section. The indicia is separated from an end of the first cylindrical section by a distance (a) that is from about 5.33 mm to about 6.10 mm. 
     When intended for use with medium-duty trucks, such as those that use M20×1.5 sized wheel studs, d 1  may be from about 18.676 mm to about 18.727 mm; d 2  may be from about 25.883 mm to about 25.984 mm; d 3  may be from about 26.988 mm to about 27.026 mm; and id may be from about 19.694 mm to about 19.732 mm. The provided indicia may then be separated from the end of the first cylindrical section by a distance (a) that is from about 5.33 mm to about 6.10 mm. 
     In an additional embodiment of the present invention, a method of inspecting a truck wheel includes: determining if a wheel stud is under-diameter; determining if a wheel nut is over-diameter; determining if a wheel nut is bell-mouthed; and determining if a bolt-hole opening in a wheel is eccentric and/or is obstructed by foreign material. Determining that the wheel stud is under-diameter may include inserting a distal end portion of the wheel stud into a bore provided in a multi-purpose gauge. Determining that a wheel nut is over-diameter may include inserting a first section of the multi-purpose gauge into a first side of the wheel nut. Determining that a wheel nut is bell-mouthed may include inserting the first section of the multi-purpose gauge into a second side of the wheel nut. Finally, determining that a bolt-hole opening in a wheel is eccentric or is obstructed may include inserting a second section of the multi-purpose gauge into the bolt-hole opening. 
     Finally, in still another embodiment, a multi-purpose gauge for inspecting a hub-piloted wheel assembly includes a unitary body having: means for determining a under-dimension of a wheel stud; means for determining an over-dimension of a wheel nut; means for determining bell-mouthing of a wheel nut; and means for determining if a bolt-hole opening in a wheel is eccentric or is obstructed. 
     The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. 
     “A,” “an,” “the,” “at least one,” and “one or more” are used interchangeably to indicate that at least one of the item is present; a plurality of such items may be present unless the context clearly indicates otherwise. All numerical values of parameters (e.g., of quantities or conditions) in this specification, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; about or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters. In addition, disclosure of ranges includes disclosure of all values and further divided ranges within the entire range. Each value within a range and the endpoints of a range are hereby all disclosed as separate embodiment. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated items, but do not preclude the presence of other items. As used in this specification, the term “or” includes any and all combinations of one or more of the listed items. When the terms first, second, third, etc. are used to differentiate various items from each other, these designations are merely for convenience and do not limit the items. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic partial cross-sectional view of a stud and nut being used to secure two wheels to a hub in a hub-piloted wheel assembly 
         FIG. 2  is an isometric view of a multi-purpose gauge for a hub-piloted wheel assembly. 
         FIG. 3  is a cross-sectional view of the gauge of  FIG. 2  taken along line  3 - 3 . 
         FIG. 4  is a schematic partial cross-sectional view of a multi-purpose gauge for a hub-piloted wheel assembly being used to determine if a wheel stud is under-diameter. 
         FIG. 5  is a schematic partial cross-sectional view of a multi-purpose gauge for a hub-piloted wheel assembly being used to determine if a wheel nut is over-diameter. 
         FIG. 6  is a schematic partial cross-sectional view of a multi-purpose gauge for a hub-piloted wheel assembly being used to determine if a wheel nut is bell-mouthed. 
         FIG. 7  is a schematic cross-sectional view of a multi-purpose gauge for a hub-piloted wheel assembly being used to determine if a bolt-hole opening in a wheel is eccentric or is obstructed by foreign material. 
         FIG. 8  is a schematic cross-sectional view of a multi-purpose gauge for a hub-piloted wheel assembly being used to determine if a bolt-hole opening in a wheel is over-diameter. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the drawings, wherein like reference numerals are used to identify like or identical components in the various views,  FIG. 1  schematically illustrates a hub-piloted wheel assembly  10 . As shown, a wheel stud  12  and a wheel nut  14  cooperate to secure a first wheel  16  and a second wheel  18  to a wheel hub  20 . In typical applications, the wheel stud  12  is threaded bolt, that is secured into the hub  20  through, for example, the use of a knurled portion  22 . The wheel stud  12  extends through a bolt-hole opening  24  in each of the first wheel  16  and the second wheel  18 , where the wheel nut  14  applies a compressive load directly to the second wheel  18 . The wheel nut  14  is typically a flanged, flat bottom nut that is tightened to a predetermined torque. 
     In heavy duty trucking applications (i.e., Class 7 or 8 trucks as specified by the U.S. Federal Highway Administration), the wheel stud  12  is typically an M22×1.5 sized bolt, and ten such wheel studs  12  may be used to secure the wheels  16 ,  18  to the hub  20 . In these applications, the wheel nut  14  may be torqued against the second wheel  18  to a torque of, for example, from about 610 to about 678 N-m. In medium duty trucking applications (i.e., Class 5 or 6 trucks), the studs may include M20×1.5 bolts, and in even lighter duty applications M18×1.5 or M16×1.5 bolts may be used. 
     Particularly in heavy duty applications, due to the extreme force that is used to secure the wheels  16 ,  18  to the hub  20 , it is critically important that both the studs  12  and nuts  14  are properly dimensioned. If a stud  12  is under dimensioned, or if a nut  14  is over dimensioned, excess forces may be developed that could result in damage to either the nut  14  or the stud  12 , which may compromise the integrity of the wheel assembly  10 . 
       FIG. 2  illustrates a multipurpose gauge  30  that may be used by a wheel technician to quickly assess whether each stud  12  and nut  14  are properly dimensioned, as well as whether the bolt-hole opening  24  in each wheel  16 ,  18  is both round, and not oversized. The gauge  30  has a unitary body and may include a quick disconnect feature  32  that allows the technician to carry the gauge  30  on a key ring, such that it can be available at all times. 
     The gauge  30  is preferably made from a resilient material that can resist both deformation and wear (i.e., the type of deformation/wear that may be experienced through repeated use or through impacts with other objects). Additionally, it is preferable that the material be selected so that it maintains applicable tolerances throughout a usable temperature range of about −30 degrees C., to about 50 degrees C. Suitable materials may include alloys of steel or aluminum. It is also preferable that the gauge  30  be made from a material that resists corrosion when exposed to harsh environments. For example, alloys of stainless steel may be used, or the gauge  30  may be anodized following its initial fabrication. 
     As further illustrated in  FIG. 2 , the gauge  30  may include three distinct cylindrical sections  34 ,  36 ,  38  having progressively larger outer diameters. The quick disconnect feature  32  may be provided in a first end  40  of the gauge  30  that is adjacent to the first cylindrical section  34 , while a bore  42  may be provided in a second end  44  of the gauge  30  (i.e., opposite the first end  40 ) that is adjacent to the third cylindrical section  38 . 
       FIG. 3  provides a cross-sectional view of the gauge  30  for enhanced clarity. As illustrated in  FIG. 3 , the first section  34  may have a first outer diameter d 1 , the second section  36  may have a second outer diameter d 2 , and the third section  38  may have a third outer diameter d 3 , where d 1 &lt;d 2 &lt;d 3 . Additionally, each section  34 ,  36 ,  38  may be aligned along a common longitudinal axis  46 . As will be discussed below, the diameters d 1 , d 2 , d 3  maybe selected according to the sizing of the wheel nuts  14  and bolt-hole openings  24 . Additionally, the bore  42  may have a controlled inner diameter id based on the sizing of the wheel studs  12 , where id&gt;d 1 . Finally, an indicia  48 , such as a scribe line  48  may be provided on an outer surface of the first section  36  at a distance a measured from the first end  40 . While the first end  40  need not be entirely planar and/or transverse to the longitudinal axis  46 , the distance a to the scribe line  48  is measured from a point proximate the first end  40  at which the first section  34  initially tapers to a diameter that is less than the prescribed first outer diameter d 1 . As additionally illustrated, a smaller bore  50  may be provided in the first end  40  of the first section  34  to receive the quick disconnect feature  32 . 
     Table 1 below provides examples of max/min dimensions for each of d 1 , d 2 , d 3 , id, and a, for gauges that are intended to be used with each of the different heavy, medium, and light duty trucking applications described above. 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Max/min gauge dimensions in mm 
               
               
                 according to application and stud size 
               
             
          
           
               
                   
                 Heavy Duty 
                 Medium Duty 
                 Light Duty 
                 Light Duty 
               
               
                   
                 M22 × 1.5 
                 M20 × 1.5 
                 M18 × 1.5 
                 M16 × 1.5 
               
               
                   
                   
               
             
          
           
               
                 d1 
                 20.727/20.676 
                 18.727/18.676 
                 16.727/16.627 
                 14.727/14.676 
               
               
                 d2 
                 25.984/25.883 
                 25.984/25.883 
                 25.984/25.883 
                 25.984/25.883 
               
               
                 d3 
                 27.026/26.988 
                 27.026/26.988 
                 27.026/26.988 
                 27.026/26.988 
               
               
                 id 
                 21.732/21.694 
                 19.732/19.694 
                 17.732/17.964 
                 15.732/15.694 
               
               
                 a 
                 6.10/5.33 
                 6.10/5.33 
                 6.10/5.33 
                 6.10/5.33 
               
               
                   
               
             
          
         
       
     
     The gauge  30  may have five separate functionalities, as schematically illustrated in  FIGS. 4-8 . More specifically, the gauge  30  may be used to: determine if a wheel stud  12  is under-diameter, such as generally shown at  60  in  FIG. 4 ; determine if a wheel nut  14  is over-diameter, such as generally shown at  62  in  FIG. 5 ; determine if a wheel nut  14  is bell-mouthed, such as generally shown at  64  in  FIG. 6 ; determine if a bolt-hole opening  24  is eccentric or is obstructed, such as generally shown at  66  in  FIG. 7 ; and determine if a bolt-hole opening  24  is oversized, such as generally shown at  68  in  FIG. 8 . 
     Referring to  FIG. 4 , the gauge  30  may be used to determine if a wheel stud  12  is under-diameter by attempting to insert the distal end  70  of the wheel stud  12  into the bore  42  provided in the end  44  of the third section  38 . If more than about four threads enter the bore  42 , then the stud  12  may be regarded as under-diameter. More specifically, under-diameter is a condition where the major diameter (i.e., a diameter measured from radially outward peaks of the threads) is below a minimum diameter specification. This condition can contribute to galling and may reduce the torque or clamp load that can be applied through the nut  14 , which may result in wheel loosening, damage, or separation. 
     As shown in  FIG. 5 , the gauge  30  may be used to determine if a wheel nut  14  is over-diameter by attempting to insert the first section  34  of the gauge  30  into the flange-side  72  of the wheel nut  14 . If the gauge  30  enters the threaded section of the nut  14  deeper than the scribe line  48 , then the nut  14  may be regarded as over-diameter. Over-diameter is a condition where the minor diameter (i.e., a minimum interior diameter of the nut  14 , measured from the radially inward peaks of the threads) is greater than a maximum diameter specification. This may be caused through wear or improper manufacturing. An over-diameter nut  14  may cause galling and/or damage to the threads, which may result in wheel loosening, damage, or separation and/or may require the nut to be ultimately cut off. 
     As shown in  FIG. 6 , the gauge  30  may be used to determine if a wheel nut  14  is bell-mouthed by attempting to insert the first section  34  of the gauge  30  into the top-side  74  of the wheel nut  14 . If the gauge  30  enters the threaded section of the nut  14  deeper than the scribe line  48 , then the nut  14  may be regarded as bell-mouthed. Bell-mouthing is a condition where the top-side  74  of the nut  14  at the threads opens up or widens. This condition causes a reduction in the engagement between the nut  14  and the stud  12 , which may reduce the torque or clamp load that can be applied through the nut  14 . 
     As shown in  FIG. 7 , the gauge  30  may be used to determine if a wheel bolt-hole opening  24  is eccentric (i.e., elongated or oblong, such as through wear and/or damage) by inserting both the first and second sections  34 ,  36  of the gauge  30  through the opening  24  (i.e., preferably from a reverse side  76 ), until the wheel disc  78  contacts the ledge  80  between the second and third sections  36 ,  38 . If the bolt-hole opening  24  flushly contacts the second section  36  of the gauge  30  around the entire circumference, or has a uniform gap around the entire circumference, then the bolt-hole opening  24  is not eccentric. To facilitate this inspection, the ledge  80  may be angled between the second section  36  and the third section  38  so that it may self-center within the opening  24 . Visual inspection may be aided by shining a bright light on the reverse side  76  of the wheel disc  78  to search for light leakage around the circumference of the gauge  30 . If light is observed, then a technician may conclude that the bolt-hole opening  24  is not eccentric. 
     Finally, as shown in  FIG. 8 , the gauge  30  may be used to determine if a bolt-hole opening  24  is oversized by attempting to pass the third section  38  of the gauge  30  through the opening  24 . This may be performed either as shown in  FIG. 7  (i.e., by inserting the first and second sections  34 ,  36  through the opening  24  and examining whether the third section  38  is restricted from passing through the opening  24 , or as shown in  FIG. 8 , where the end  44  of the third section  38  is attempted to be directly inserted through the opening  24 . If the gauge  30  passes through the opening  24 , though is circular, a technician may be encouraged to review the wheel specifications, as some wheels are intentionally manufactured with oversized bolt-hole openings  24  (despite industry recommendations to the contrary). 
     If the stud  12  is under-dimensioned, the stud  12  should be removed from the hub  20  and replaced. Similarly, if the nut  14  is over-dimensioned or bell-mouthed, it should be discarded and replaced. If the bolt-hole opening  24  in the wheel is eccentric, it should be replaced, and if there is an obstruction or interference present in or about the bolt-hole opening  24 , it should be cleaned. Finally if the bolt-hole opening  24  in the wheel is over-dimensioned, specifications for the wheel should be reviewed, and the wheel should be replaced if the openings are unintentionally over-dimensioned. 
     While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not as limiting.