Abstract:
An auxiliary axle or lift axle is pivotally mounted to the frame of a vehicle for selectively providing additional flotation for the vehicle. A pair of frame brackets are secured to the frame members of the vehicle and have horizontally disposed mounting plates adjacent to the lower ends thereof. A bracket member extends downwardly from one end of the mounting plate and has a pair of spaced-apart slots formed therein. A bracket member also extends downwardly from the other end of the frame bracket and has a pair of spaced-apart first and second slots formed therein. The hanger brackets are adjustably secured to the bracket members to permit the axle assembly to be mounted on frame members having varying distances therebetween and having varying frame thicknesses. The novel method of securing the hanger brackets to the frame brackets is also disclosed.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to an axle suspension mounting system and more particularly to a lift axle suspension mounting system wherein the lift axle suspension assembly is secured to the frame of a truck between the tandem axles and the cab of the truck. The lift axle suspension assembly may also be mounted on the rearward end of the frame rearwardly of the tandem axles. The lift axle suspension assembly is pivotally movable with respect to the vehicle between a first position in which the wheels of the lift axle are elevated and a second position in which the wheels of the lift axle engage the ground. More particularly, the lift axle suspension mounting system of this invention is designed to fit truck frames having varying dimensions. Even more particularly, the lift axle suspension mounting system of this invention represents an improvement over assignee&#39;s earlier lift axle suspension mounting system described and shown in U.S. Pat. No. 6,316,993 B1. Although the axle suspension system of this invention is well suited for use with a lift axle, it is also well suited for use with auxiliary axles which are not of the lift type. 
     Description of the Related Art 
     Lift axle assemblies have been used for many years on work vehicles such as transit concrete mixers, gravel trucks, etc. The lift axle assemblies of the prior art permit the vehicle to carry more weight while still meeting the regulations governing the weight which the vehicles can legally carry over federal and state highways. Most of the prior art lift axle assemblies are pivotally movable with respect to the frame of the vehicle so that the wheels of the lift axle assembly may be pivotally moved from a ground engaging position to an elevated position. 
     Assignee&#39;s lift axle suspension mounting system described and shown in U.S. Pat. No. 6,311,993 represented a significant advance and improvement in the lift axle suspension mounting systems of the prior art. The instant invention represents a further advance in the art in that it is more convenient to assemble than the system of the &#39;993 patent. 
     SUMMARY OF THE INVENTION 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key aspects or essential aspects of the claimed subject matter. Moreover, this Summary is not intended for use as an aid in determining the scope of the claimed subject matter. 
     An axle suspension mounting system is provided which includes first and second frame brackets secured to the first and second frame members of a load-bearing vehicle. As used herein, the term vehicle includes trucks with primary and auxiliary suspensions and trailers with primary and auxiliary suspensions. Each of the first and second frame brackets include a vertically disposed first mounting plate configured to be secured to the associated frame member. A horizontally disposed and elongated second mounting plate is secured to lower end of the first mounting plate. A first bracket member extends downwardly from the first end of the frame bracket and is transversely disposed with respect to the longitudinal axis of the associated frame member. The first bracket member has first and second horizontally disposed slots formed therein. A vertically disposed second bracket member extends downwardly from the second end of the frame bracket and is transversely disposed with respect to the longitudinal axis of the associated frame member. The second bracket member has first and second horizontally disposed slots formed therein. 
     The mounting system of this invention also includes first and second hanger brackets which are adjustably secured to the first and second frame brackets. Each of the hanger brackets has a first end wall, a second end wall, a first side wall, a second wall, a top wall and a lower end. First and second mounting straps are positioned within each of the hanger brackets and are secured thereto beneath the top wall thereof. Each of the mounting straps has first and second bolts secured thereto which extend upwardly through the top wall of the hanger bracket for reception by openings in the second mounting plate of the associated frame bracket. 
     A pair of bolts extend inwardly through the slots of the first bracket member of the associated frame bracket, through holes in upper end of the first end wall for connection to nuts fixed to the first mounting strap. A pair of bolts extend inwardly through the slots of the second bracket member of the associated frame bracket, through holes in the upper end of second end wall for connection to nuts fixed to the second mounting strap. 
     Although the axle suspension system of this invention is well suited for use with a lift axle, it is also well suited for use with auxiliary axles or suspension systems which are not of the lift type. 
     It is therefore a principal object of the invention to provide an improved mounting system for a lift axle assembly or an auxiliary axle assembly for a vehicle such as a truck or trailer. 
     Still another object of the invention is to provide an axle suspension mounting system which accommodates frame width variations and frame thickness variations. 
     Yet another object of the invention is to provide an axle suspension mounting system which is extremely safe to use. 
     Yet another object of the invention is to provide an axle suspension mounting system which is quickly and easily bolted onto the frame members of the vehicle. 
     Still another object of the invention is to provide an axle suspension system which is more convenient to assemble than the prior art systems. 
     These and other objects will be apparent to those skilled in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. 
         FIG. 1  is a side view of a load-bearing vehicle having a lift arm suspension system of the pusher type secured thereto; 
         FIG. 2  is a perspective view of one of the bracket members of this invention; 
         FIG. 3  is another perspective view of the bracket member of  FIG. 2 ; 
         FIG. 4  is a top view of the bracket member of  FIG. 2 ; 
         FIG. 5  is a perspective view of the lift axle suspension mounting system of this invention; 
         FIG. 6  is another perspective view of the lift axle suspension mounting system of this invention; 
         FIG. 7  is an end view of the lift axle suspension mounting system of this invention; 
         FIG. 8  is a partial perspective view of one of the hanger brackets of this invention; 
         FIG. 9  is a perspective view of one of the mounting straps of this invention; 
         FIG. 10  is an inner side view of the mounting strap of  FIG. 9 ; 
         FIG. 11  is a partial end elevation view of the mounting system of this invention; and 
         FIG. 12  is a partial sectional view of the mounting system of this invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Embodiments are described more fully below with reference to the accompanying figures, which form a part hereof and show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the invention. However, embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. The following detailed description is, therefore, not to be taken in a limiting sense in that the scope of the present invention is defined only by the appended claims. 
     The numeral  10  refers to the lift axle suspension mounting system of this invention which represents an improvement of Assignee&#39;s U.S. Pat. No. 6,311,993 B1, the disclosure of which is relied upon to complete this disclosure if necessary. The system  10  of this invention may be used with a lift axle suspension system of the “tag” type or a lift axle suspension system of the “pusher” type. If the lift axle suspension system is of the “pusher” type, the system  10  will be secured to the longitudinally extending frame members of the vehicle between the cab of the vehicle and one or more axles which may be driven or non-driven. If the lift axle suspension system is of the “tag” type, the system  10  will be secured to the frame members of the vehicle rearwardly of one or more axles which may be driven or non-driven. In the description of the preferred embodiment, the system  10  will be described as being of the pusher type with it being understood that the system  10  could be used with the tag type lift axle suspension system. 
     The system  10  is mounted to a vehicle  12  including first and second longitudinally extending frame members  14  and  16  having forward and rearward ends, and inner and outer sides. Vehicle  12  may be any vehicle requiring additional flotation in order for the vehicle to comply with state and federal highway regulations. As used herein, the term vehicle includes trucks with primary and auxiliary suspensions and trailers with primary and auxiliary suspensions. 
     Frame brackets  20  and  20 ′ are bolted to frame members  14  and  16  by bolts  17  and  17 ′ respectively at the forward ends thereof if of the pusher type or at the rearward ends of the frame members  14  and  16  if of the tag type as will be described hereinafter. Inasmuch as frame bracket  20 ′ is a mirror image of frame bracket  20 , only frame bracket  20  will be described in detail with “′” indicating identical structure on frame bracket  20 ′. Frame bracket  20  includes a vertically disposed first mounting plate portion  22  having an upper end  24 , a lower end  26 , a first end  28 , a second end  30 , an outer side  32  and an inner side  34 . Mounting plate portion  22  has a plurality of bolt opening  36  formed therein to enable frame bracket  20  to be bolted to frame member  14 . A horizontally disposed mounting plate portion  38  is secured to the lower end of mounting plate portion  22  and has bolt openings  40 ,  42 ,  44  and  46  formed therein. As seen in  FIG. 4 , bolt openings  42  and  46  are slot-shaped with the lengths or longitudinal axis thereof being disposed transversely with respect to the longitudinal axis of mounting plate portion  38 . Gusset plates  48  and  50  are secured to mounting plate portion  38  and the outer side of mounting plate portion  22  by welding. Vertically disposed bracket members  52  and  54  extend downwardly from the first and second ends of mounting plate portion  38  respectively. Bracket member  52  has elongated and horizontally disposed slots  56  and  58  formed therein and bracket member  54  has elongated and horizontally disposed slots  60  and  62  formed therein. If so desired, bracket members  52  and  54  could be integrally formed with gusset plates  48  and  50  respectively. 
     The numeral  64  refers to a hanger bracket which is secured to frame bracket  20  with the numeral  64 ′ referring to a hanger bracket which is secured to frame bracket  20 ′. Inasmuch as hanger bracket  64 ′ is a mirror image of hanger bracket  64 , only hanger bracket  64  will be described in detail with “′” indicating identical structure on hanger bracket  64 ′. 
     Hanger bracket  64  includes a vertically disposed outer side wall  66  having an upper end  68 , a lower end  70 , a first end  72  and a second end  74 . Hanger bracket  64  also includes a vertically disposed inner side wall  76  having an upper end  78 , a lower end  80 , a first end  82  and a second end  84 . Hanger bracket  64  further includes a first end wall  86  having an upper end  88  and a lower end  90  which is secured to the first ends  72  and  82  of side wall  66  and  76  respectively. First end wall  86  is a port of a connector structure  82  which interconnects hanger brackets  64  and  64 ′. Hanger bracket  64  also includes a second end wall  92  which is secured to the second ends  74  and  84  of side walls  66  and  76  respectively. End wall  92  includes a vertically disposed plate  94  at its upper end which has bolt openings  96  and  98  formed therein. The lower end of end wall  92  has an air spring mounting plate  100  secured thereto. Plate  100  has the lower end of an air spring  102  mounted thereon. End wall  92  has an opening  104  formed therein. A top wall  106  extends over the upper ends of walls  66 ,  76 ,  86  and  92 . Top wall  106  has bolt openings  108 ,  110 ,  112  and  114  formed therein. 
     The numeral  116  refers to a lift pivot pin which extends between outer side wall  66  and inner side wall  76  of hanger bracket  64 . The numeral  118  refers to a lift arm which will be a pusher arm if the lift axle suspension system is of the pusher type or a trailing arm if the lift axle suspension system is of the tag type. 
     The rearward end of lift arm  118  extends upwardly through opening  104  in end wall  92  of hanger bracket  64  and has its inner end pivotally secured to lift pivot pin  116 . Lift arm  118  has an air spring mounting plate  120  secured to the underside thereof. The upper end of air lift spring  102  is secured to plate  120  in conventional fashion. As will be explained hereinafter, end wall  86  has a pair of bolt openings formed therein adjacent the upper end  88  of end wall  86 . 
     The numeral  126  refers to a first mounting strap which is positioned within hanger bracket  64  at the upper first end thereof. Strap  126  includes a vertically disposed strap portion  128  and a horizontally disposed strap portion  130  which extends transversely from the upper end of strap portion  128 . Strap portion  130  has bolt openings  132  and  134  formed therein. Strap portion  128  has bolt openings  136  and  138  formed therein. Nut  140  is welded to the inner side of strap portion  128  so as to register with bolt opening  136 . Nut  142  is welded to the inner side of strap portion  128  so as to register with bolt opening  138 . A nut  144  is welded to the underside of strap portion  130  so as to register with bolt opening  132  thereof. 
     A bolt  146  extends downwardly through bolt opening  108  in top wall  106  of hanger bracket  64  and through bolt opening  132  in strap portion  130  for threadable connection to nut  144 . The head  148  of bolt  146  is spaced above top wall  106  for a purpose to be explained hereinafter. A bolt  150  having a head  152  and a threaded shank  154  extends upwardly through bolt opening  134  in strap portion  130  and extends upwardly through bolt opening  110  in top wall  106 . The head  152  of bolt  150  is welded to the underside of strap portion  130 . 
     The numeral  158  refers to a second mounting strap which is positioned within hanger bracket  64  at the upper second end thereof. Strap  158  includes a vertically disposed strap portion  160  and a horizontally disposed strap portion  162  which extends transversely from the upper end of strap portion  160 . Strap portion  162  has bolt openings  164  and  166  formed therein. Strap portion  160  has bolt openings  168  and  170  formed therein. Nut  172  is welded to the inner side of strap portion  160  so as to register with bolt opening  168 . A nut (not shown) is welded to the inner side of strap portion  160  so as to register with bolt opening  170 . A nut  176  is welded to the underside of strap portion  162  so as to register with bolt opening  164 . 
     A bolt  178  extends downwardly through bolt opening  112  in top wall  106  of hanger bracket  64 ′ and through bolt opening  164  in strap portion  162  for threadable connection to nut  176 . The head  180  of bolt  178  is spaced above top wall  106  for a purpose to be explained hereinafter. A bolt  182  having a head  184  and a threaded shank  186  extends upwardly through bolt opening  166  in strap portion  162  and extends upwardly through bolt opening  114  in top wall  106  of hanger bracket  64 . The head  184  of bolt  182  is welded to the underside of strap portion  162 . 
     The method of attaching the lift axle suspension system to the vehicle  12  will now be described. The frame brackets  20  and  20 ′ are secured to the frame members  14  and  16  by the bolts  17  and  17 ′. The hanger brackets  64  and  64 ′, with the other components of the lift axle suspension system, are positioned beneath the mounting plates  38  and  38 ′ of the frame brackets  20  and  20 ′. The hanger brackets  64  and  64 ′ are then raised with respect to the frame brackets  20  and  20 ′. With respect so that the bolt  150  is received by the slotted opening  42  in mounting plate  38 , the head  148  of bolt  146  is received by opening  40 , the bolt  182  is received by the slotted opening  46  and the head  178  of bolt  178  is received by opening  44 . Nuts  190  and  192  are then threadably secured to bolts  150  and  182 . The bolts  150 ,  146 ,  182 ,  178  act as guides for properly positioning the hanger  64  with respect to the frame bracket  20 . The same is also true with respect to hanger bracket  64 ′. 
     Bolt  194  is then extended inwardly through slot  56  in bracket member  52 , through an opening in end wall  72 , and through opening  136  in mounting strap  126  for threadable connection to nut  140 . Bolt  196  is then extended inwardly through slot  58  in bracket member  52 , through an opening in end wall  72 , and through opening  138  in mounting strap  126  for threadable connection to nut  142 . The slots  56  and  58  permit the hanger bracket  64  to be adjusted with respect to frame bracket  20  or vice versa to accommodate difference in the distance between frame members  14  and  16  or various frame member thicknesses. 
     The second end of hanger bracket  64  is secured to bracket member  54  by a pair of bolts  198  in the same manner as just described. The bolts  146  and  178  act as torque reactors which stabilize the frame brackets and hanger brackets during the tightening of the various nuts. 
     The hanger bracket  64 ′ is secured to frame bracket  20 ′ in the same manner as that described herein above. 
     Thus it can be seen that the invention accomplishes at least all of its stated objectives. 
     Although the invention has been described in language that is specific to certain structures and methodological steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures and/or steps described. Rather, the specific aspects and steps are described as forms of implementing the claimed invention. Since many embodiments of the invention can be practiced without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.