Abstract:
A mounting arrangement for a V-rod in a vehicle suspension includes an axle housing having a mounting cavity formed thereon and a joint member installed in the mounting cavity so that a joint coupling extends outward from the axle housing. The joint member may include a ball joint mounted on a post mountable in the mounting cavity. The mounting cavity may be formed in a boss provided on the axle housing.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to vehicle suspensions, and more particularly, to suspensions including V-rods, that is, V-shaped structures connected between the vehicle frame and axle. 
       BACKGROUND AND SUMMARY 
       [0002]    In vehicle suspensions, particularly those with air springs, it is known to use V-rods (also known as V-stays and V-bars) mounted between the frame and the axle to stabilize the axle in the lateral and fore-and-aft directions, while allowing vertical travel. A prior arrangement for mounting the V-rod to the axle, as disclosed in U.S. Pat. No. 6,439,588 to Svensson, includes a plate structure mounted with four bolts on the axle housing. The plate supports a joint member to which the point end or vertex of the V-rod is attached. 
         [0003]    When the axle is a drive axle housing, the plate is typically mounted to the differential carrier, that is, the portion of the axle housing containing the gearing that distributes driving torque from the drive shaft to the wheels. 
         [0004]    The arrangement of a mounting plate to the axle housing or differential carrier to support a V-rod presents difficulties. The mounting plate is a separate part, increasing weight and cost to the assembly. In addition, the mounting plate positions the V-rod joint at a height relative to the frame that may interfere with vertical suspension travel. 
         [0005]    The invention overcomes these problems in the art with a mounting arrangement for a V-rod that includes a joint member mounted directly to the axle housing in a cavity formed therein. 
         [0006]    According to the invention, a mounting arrangement for a V-rod in a vehicle suspension includes an axle housing having a mounting cavity formed thereon and a joint member installed in the mounting cavity so that a joint coupling extends outward from the axle housing. 
         [0007]    According to an embodiment of the invention, the joint member comprises a post or stud installable in the mounting cavity and a joint coupling mounted on the post. 
         [0008]    According to the invention, the mounting cavity is formed with a threaded lower part and an unthreaded upper part, the upper part being wider than the lower part, and the post includes a first threaded portion and a second unthreaded portion or pilot, the pilot being wider than the first threaded portion. The second portion of the post and the upper part of the mounting cavity are sized for an interference fit. Thus, the threaded portion of the post and the threaded part of the cavity align and draw the post into the cavity to engage the pilot and upper cavity part. 
         [0009]    According to an embodiment, the cavity is formed on an upper surface of the axle housing. If a differential carrier is part of the axle, the cavity is formed on an upper surface of the differential carrier. 
         [0010]    According to one embodiment, the joint member is a joint ball mounted on the post. 
         [0011]    Alternatively, the joint member is a socket member to receive a ball joint of a V-rod. 
         [0012]    In yet another alternative, the joint member is a bracket to receive a bushing member of a V-rod. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The invention will be better understood by reference to the following detailed description read in conjunction with the appended drawings, in which: 
           [0014]      FIG. 1  is a perspective view of a truck frame and axle showing a V-rod attached between the frame and axle according to the prior art; 
           [0015]      FIG. 2  is a perspective view of an axle housing with a V-rod mounting structure in accordance with an embodiment of the invention; 
           [0016]      FIG. 3  is an exploded view of an embodiment of a joint member; and, 
           [0017]      FIG. 4  is a section view of the axle housing of  FIG. 2  showing internal structure of a mounting cavity with a joint member according to the invention installed therein. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]      FIG. 1  is a perspective view of a rear end portion of a truck frame illustrating a V-rod connection of the prior art. The truck frame has side rails  1  and  2  joined by a cross members  3  and  4 . An axle  11  is connected to the frame to extend laterally relative to the frame rails  1 ,  2  by a suspension apparatus including control arms  10  and support arms  6 ,  7 . The support arms  6 ,  7  include seats  8  for air springs (not illustrated) which may be disposed between the support arms  6 ,  7  and frame rails  1 ,  2 . The suspension apparatus is not fully illustrated as air suspensions are familiar to those skilled in the art and many examples are available. The invention, while particularly suitable for air suspensions, is not limited to any particular air suspension, and may be used for other types of suspensions as well. 
         [0019]    A single axle  11  is shown in  FIG. 1  for simplicity; of course, a vehicle rear axle set up may have two or three axles. 
         [0020]    The axle  11  includes an axle housing  12  which houses the gearing that receives driving torque from the drive shaft (not illustrated) and distributes it to the wheel spindles  20 ,  21  for driving the wheels. A V-rod  13  is formed by two legs  15 ,  16  joined to form a vertex  17 . The V-rod  13  is connected at the vertex  17  to the axle housing  12  and by the legs to the frame rails  1 ,  2 . As is known, a V-rod provides lateral and longitudinal stability to the axle. 
         [0021]    The vertex  17  of the V-rod is attached to a plate  14  mounted to a differential carrier  18  itself mounted on the axle housing  12 . The arms  15 ,  16  of the V-rod are attached by brackets  21  (one bracket is visible) to the frame rails  1 ,  2 . 
         [0022]      FIG. 2  shows in perspective view a mounting arrangement for the V-rod to the axle housing  20  in accordance with an embodiment of the invention. In  FIG. 2 , the axle housing  20  includes a differential carrier  21  mounted to an upper side of the axle housing. The axle housing  20  terminates with spindles  22  (only one is shown, the opposite end being sectioned) to support the wheels (not shown in this view). According to the invention, a joint member  50  for the V-rod is mounted directly to the axle housing  20 , which, in the illustrated embodiment, is directly to the carrier  21 . The carrier  21  includes a boss or protrusion  28  formed on an outer surface to accommodate a mounting cavity for the joint member  50 . The boss and cavity may be provided on an upper surface as shown in  FIG. 2 . 
         [0023]      FIG. 3  is an exploded view of a joint member  50  in accordance with the invention. The joint member  50  includes a post  52  and a joint ball  54 . The post  52  includes a lower portion  55  having a pilot  56  and a threaded shaft  58 . The pilot  56  is wider than the threaded shaft  58 , that is, has a diameter greater than the diameter of the threaded shaft. 
         [0024]    An upper portion or neck  60  of the post  52  supports the joint ball  54 . The post  52  also includes a hex shaped collar  62  which allows the post to be rotated by a tool for installing in the boss  28 , as described below. A bolt  64  inserted through a hole  66  in the joint ball  54  mates with a threaded hole  68  in the neck  60  to secure the joint ball to the post  52 . 
         [0025]      FIG. 4  shows the mounting arrangement of the invention in section view. The carrier  21  boss  28  includes a mounting cavity  70  formed as a stepped hole having a threaded lower part  72  and a relatively wider, unthreaded upper part  74 . The lower part  72  is sized and the threads are formed to mate with the threaded shaft  58  of the post  52 . The upper part  74  is sized to have a diameter slightly less than a diameter of the pilot  56  to provide an interference fit between the upper part  74  and pilot  56 . As the shaft  52  is screwed into the mounting cavity  70 , the pilot  56  is drawn into and pressed into the upper part  74 . 
         [0026]    As shown in  FIG. 4 , the V-rod (one arm  44  being shown) is mounted to the joint ball  54  by a socket  80  carried on the vertex  46  of the V-rod. 
         [0027]    Alternatively, a socket can be mounted to the post and the joint ball mounted on the V-rod. 
         [0028]    According to yet another alternative, a bracket can be formed or mounted on the shaft to receive a bushing assembly mounted on the V-rod. 
         [0029]    The invention has been described in terms of preferred principles, structure and embodiments; however, those skilled in the art will understand that substitutions may be made of components described here without departing from the scope of the invention as recited in the following claims.