Abstract:
A wheel hub having two separable components. The wheel hub includes a sleeve rotatably mounted to a vehicle axle. A wheel-mounting flange for mounting a wheel of the vehicle is positioned substantially around the sleeve, and a bolting lip of a brake rotor (or brake drum) is sandwiched between the wheel-mounting flange and a bolting flange of the sleeve.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     The present invention relates to motor vehicles and more particularly to a wheel hub that couples a wheel to an axle of a motor vehicle. 
     Conventional wheel hubs typically include a sleeve mounted for rotation around an axle. The sleeve has bearings and lubricant that provide the rotational coupling for the wheel to rotate about the axle, and the sleeve typically also includes an integrally-formed wheel-mounting flange that extends out from the outer surface of the sleeve. The wheel-mounting flange includes bolt holes through which bolts are inserted that mount the vehicle wheel to the wheel-mounting flange. 
     In conventional wheel hub arrangements, a mounting flange of a brake rotor (or brake drum) also typically include bolt holes for mounting the brake rotor or drum to the sleeve using the same bolts that are used for mounting the wheel to the wheel-mounting flange. In other words, the flange of the brake rotor is coupled to the wheel-mounting flange with the same bolts that are used to mount the wheel to the wheel-mounting flange. With this arrangement, the brake rotor is positioned “inboard” of the wheel-mounting flange, which means that the brake rotor is positioned on a side of the wheel-mounting flange away from the outside of the vehicle, or on the side of the wheel-mounting flange opposite the wheel. Because of this, when access to the brake rotor and braking components is desired, the entire wheel hub (i.e., the sleeve with its integral wheel-mounting flange) must be removed from the vehicle&#39;s axle. After the brake rotor or other components of the brake are serviced, the wheel hub must be reinstalled, which requires resetting the bearings and re-lubricating the connection. A wheel hub that allows access to the brake rotor (or brake drum) without requiring removal of the wheel hub from the vehicle&#39;s axle, would be welcomed by users of wheel hubs because it would save time and make servicing the rotor or drum easier. 
     According to the present invention, a wheel hub for a vehicle having an axle and a wheel comprises a sleeve and a wheel-mounting flange. The sleeve is rotatably mounted on the axle and has a sleeve bolting flange radially extending from its outer surface. The wheel-mounting flange removably substantially surrounds the sleeve and has a first set of mounting holes for bolting the wheel-mounting flange to the sleeve bolting flange and a second set of mounting holes for bolting the wheel to the wheel-mounting flange. The second set of mounting holes is radially more distant from the sleeve than the first set of mounting holes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional perspective view of a brake rotor mounted to a wheel hub according to the present invention; 
         FIG. 2  is a cross-sectional perspective view of the brake rotor of  FIG. 1 ; 
         FIG. 3  is a cross-sectional perspective view of a sleeve of the wheel hub of  FIG. 1 ; and 
         FIG. 4  is a perspective view of a wheel-mounting flange of the wheel hub of  FIG. 1 . 
         FIG. 5  is a perspective view of an alternative embodiment of a wheel-mounting flange of the wheel hub of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a two-component wheel hub  10  according to the present invention includes a sleeve  12  and a separate wheel-mounting flange  14 , both of which are coupled to a brake component. As will be readily apparent to those of ordinary skill in the art, the brake component is shown as a brake rotor  16  in the illustrated embodiment. However, the brake component could alternatively be a brake drum or other similar component of a braking system and still be within the spirit and scope of the present invention. 
     The wheel-mounting flange  14  is formed separately from the sleeve  12  and includes a central opening  18  that receives the sleeve  12 . As shown in  FIGS. 3 and 4 , central opening  18  has an inner edge  38  that is scalloped to define one or more cavities  39  so that flange  14  can pass over projections or bolting lugs  40  that project from the sleeve  12 . The scalloped inner edge  38  of the central opening  18  is designed so that the wheel-mounting flange  14  can be rotationally positioned to receive or pass over the bolting lugs  40 . A series of bolts (not shown) extend through bolt holes  20  of a sleeve bolting flange  22  extending radially from the sleeve  12 . The bolts also extend through a first set of mounting holes  24  of the wheel-mounting flange  14  and couple the wheel-mounting flange  14  to the sleeve  12  and to the brake rotor  16 , as discussed below. 
     The brake rotor  16  is formed to include a bolting lip  26 , which also includes a plurality of bolt holes  28 . The bolt holes  28  are aligned with the bolt holes of the sleeve  12  and with the first set of mounting holes  24  of the wheel-mounting flange  14  to sandwich the bolting lip  26  between the wheel-mounting flange  14  and the bolting flange  22 . This securely couples the brake rotor  16  to the wheel hub  10 . Like the wheel-mounting flange  14 , the brake rotor  16  also includes a scalloped inner edge  42  providing one or more cavities  41  to allow the brake rotor  16  to pass over the bolting lugs  40 , as shown in  FIG. 2 . 
     With the sleeve  12  rotationally coupled to the axle, the brake rotor  16  is installed by rotating it so that its scalloped inner edge  42  is aligned to pass over the bolting lugs  40 . The brake rotor  16  is then moved axially along the sleeve  12  until the bolting lip  26  abuts the bolting flange  22  of the sleeve  12 . Next, the wheel-mounting flange  14  is rotated so that its scalloped inner edge  38  is aligned to pass over the bolting lugs  40 . The wheel-mounting flange  14  is then moved axially along the sleeve  12  until it abuts the bolting lip  26  of the brake rotor  16 , thus sandwiching the bolting lip  26  between the wheel-mounting  14  and the bolting flange  22  of the sleeve  12 . 
     In addition to the first set of mounting holes  24 , the wheel-mounting flange  14  includes a second set of mounting holes  30  located radially outwardly from the first set of mounting holes  24 . The second set of mounting holes  30  receive bolts  32  that are used to couple a wheel (not shown) to the wheel-mounting flange  14 . In this way, a wheel is securely mounted to the wheel hub  10  and rotates with the sleeve  12 , the wheel-mounting flange  14 , and the brake rotor  16 . The sleeve  12  will contain the lubricant and bearings necessary to provide the rotational coupling between the sleeve  12  and an axle (also not shown) positioned within the sleeve  12 . 
     The invention provides several advantages. With reference to  FIG. 1 , it can be seen that a wheel (again, not shown) and the wheel-mounting flange  14  to which it is mounted, can be removed to permit easy access to the brake rotor  16  without removing the sleeve  12  from an axle. In this way, the brake rotor  16  and other components (not shown) of the vehicle&#39;s braking system can be accessed and serviced without removing the sleeve  12 . Removal of the sleeve  12  requires re-packing the bearings and re-lubricating the joint when the sleeve  12  is later remounted on the axle. 
     At the same time, the present invention allows the brake rotor  16  to be mounted “inboard” of the wheel-mounting flange  14 . Previously, with a brake rotor mounted inboard of a wheel-mounting flange, the entire hub, which, as mentioned, typically includes an integrally-formed wheel-mounting flange, would need to be removed from the axle to access the braking components. 
     In previous wheel-mounting systems, if it was desired to permit removal of a brake rotor without having to remove the wheel hub, the brake rotor would have been mounted “outboard” of the wheel-mounting flange of the wheel hub. When mounted outboard, the brake rotor had to have a diameter large enough to fit over the wheel-mounting flange. As shown in  FIG. 1 , the wheel hub  10  allows access to the brake rotor  16  by simply removing the wheel-mounting flange  14 , even though the brake rotor  16  is “inboard” of the wheel-mounting flange  14 . 
     Further, the second set of mounting holes  30 , which receive the bolts  32 , can be positioned at various radial locations over the wheel-mounting flange  14  without regard for the diameter of the brake rotor  16 . As shown in  FIG. 1 , the second set of mounting holes  30  are positioned radially more distant from the sleeve  12  than the first set of mounting holes  24  which receive the bolts that couple the brake rotor  16  to the wheel hub  10 . This arrangement allows different wheel-mounting flanges  14  having differently positioned mounting holes  30  to be used with the same brake rotor  16 . The wheel-mounting flange  14  can be changed out with another wheel-mounting flange without removing the sleeve  12  from the axle. As can also be seen in  FIG. 1 , the wheel (not shown) that mounts to the wheel-mounting flange  14  can include a set of mounting holes arranged in a circle with a greater diameter  34  than a diameter  36  of the brake rotor  16 . In this way, brake rotors or brake drums with relatively small diameters can be used with wheels that have mounting holes with relatively larger diameters. A brake rotor or brake drum with a relatively small diameter may be desired for cost, weight, or other reasons that will be apparent to those of ordinary skill in the art. 
     Although the invention has been described in detail with reference to certain described constructions, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.