Abstract:
A single unit that combines the advantages of a rear spring spacer block and a traction bar. The rigidity of the traction bar and design of the spacer block eliminate wheel hop and axle wrap while maintaining a level vehicle drive height. No welding is required to install the device, the device is length and height adjustable for a plethora of vehicle applications and the factory ride and handling are preserved.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Often today, Light trucks, Sport Utility Vehicles, and more, can be seen sitting atop towering truck suspension lift kits. Aftermarket speciality suspension systems that raise the vehicle&#39;s body not only make a style statement but also allow for higher ground clearance and larger tire placement. The problem with installing suspension lift kits, is that vehicle performance and handling can be severely impacted. 
         [0002]    Drivers of these vehicles have come to expect a smooth ride while maintaining the ability to tow heavy loads or jump obstacles. Industry has responded to consumer demand by reducing the spring rate of the leaf springs to provide the desired smoother ride. 
         [0003]    Unfortunately, axle wrap is a problem that often plagues soft leaf sprung vehicles. Additionally, the problem of axle wrap and the resulting wheel hop are compounded by lift kits that increase the distance between the axle and the springs. Axle wrap is one of the biggest concerns with a spring over axle lift. 
         [0004]    Axle wrap occurs when the torque on the axle tube tries to rotate the axle pinion up when under power. This twist causes the leaf springs to twist up into an ‘S’ shape then snap back to it&#39;s standard configuration when the counter torque developed by the deformed spring exceeds that of the spinning tires, which leads to loss of traction, wheel hop, and all too often broken parts. With a spring over axle lifted vehicle, axle wrap (also called spring wrap) is usually worse because there is more leverage (due to the increase in distance between the axle and springs) for the twisting axle to work against the springs. 
         [0005]    This new invention utilizes and combines both known and new technologies in a unique and novel configuration to fulfill an industry need and overcome the aforementioned problems of “axle wrap.” It utilizes a stiffened, telescoping adjustable set of traction members pivotally coupled to a height selected set of spacer blocks, that may be affixed to the vehicle between the spring assembly and the axle mount. 
       SUMMARY OF THE INVENTION 
       [0006]    The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a single, adjustable, suspension system capable of eliminating axle wrap and wheel hop while maintaining a level vehicle drive height for a multitude of different vehicle length applications. The present invention advantageously links the traction bar devices pivotally to a single axle spacer block (available in the various commercial heights) and removes the need for axle welding or the stacking of lift blocks. The spacer block section utilizes interchangeable plates that allow for the vertical adjustment of the vehicle&#39;s axle with respect to the spring assembly for further suspension/driveline tuning. Additionally, the invention is inexpensive to manufacture, adaptable to a plethora of different vehicles, sturdy, and requires no welding by the consumer to adjust and mount to the vehicle. 
         [0007]    It has many of the advantages mentioned heretofore and many novel features that result in a new improved adjustable vehicle traction bar which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof. 
         [0008]    The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a side view of the preferred embodiment mounted to a vehicle; 
           [0010]      FIG. 2  is a partial top perspective view of the traction block, bracket arm, top plate, upper bump-stop U-bolt bracket, and U-bolts; 
           [0011]      FIG. 3  is an axle end perspective view of the preferred embodiment; 
           [0012]      FIG. 4  is a perspective view of several possible embodiments of spring pin adjustment plates and peg adjustment plates; 
           [0013]      FIG. 5  is a perspective view of the inner traction tube and clamping coupler; 
           [0014]      FIG. 6  is a perspective view of the outer traction tube; 
           [0015]      FIG. 7  is a side view of the traction tube assembly; 
           [0016]      FIG. 8  is a perspective side view of the frame bracket; and 
           [0017]      FIG. 9  is a partial cross-sectional view of the inner traction tube mounted in the frame bracket. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    The present invention provides an adjustable rear suspension device that provides vehicle owners a single product that replaces the need for purchasing an adjustable traction bar and a rear axle spacer; it allows a vehicle to keep a level ride height while limiting axle wrap and wheel hop and can be length adjusted for different truck cab, and box configurations. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting. 
         [0019]    Referring now to FIG.  1 ., a side view of the preferred embodiment of the traction block assembly  2 , the general arrangement of all the components can be seen. A traction block  4  resides between the axle  6  and leaf spring assembly  8 . Two U-bolts  10  (only one U-Bolt  10  is visible in  FIG. 1 ) secure the traction block  4  around the leaf spring assembly  8 . The U-bolts pass around the axle  6  through orifices in the traction block  4  (not visible) and around the leaf spring assembly  8  and are finally secured via the upper bump-stop U-bolt bracket  12  with a standard washer and nut assembly  11 . Additionally, the upper bump-stop U-bolt bracket  12  contains four upper bump-stop mounting orifices  3  and a receiving orifice  13  (See  FIG. 3 ) to accommodate the spring pin (not shown.) The spring pin extends from the bottom side of the lowermost spring and positions the spring assembly with respect to the upper bump-stop U-bolt bracket  12 . The bracket arm  20 , is connected to the outer traction tube  22  via the traction tube mount  24 . Also visible is the gusset plate  26  on outer traction tube  22 . The clamping coupler  28  couples the outer traction tube  22  to the inner traction tube  30 . The inner traction tube  30  mounts to the vehicle frame  32  via the frame bracket  34 . Since the inner traction tube  30  and the outer traction tube  22  form a telescoping assembly, the gusset plate is a linear stiffening member to strengthen the hollow outer traction tube  22 . 
         [0020]    Referring now to  FIG. 2 , the traction block  4  has an “L” shaped, boxed or generally enclosed construction. In the preferred embodiment, the top plate  14  of traction block  4  has four slightly elongated mounting orifices  16  for receiving the U-bolts  10 . A removable and interchangeable spring pin adjustment plate  21  contains three spring pin adjustment orifices  18 . The top plate  14  contains a chamfered orifice (not pictured) dimensionally sized to accept one of the spring pin adjustment plates  21 , such that when the spring pin adjustment plate  21  is set into the chamfered orifice the top plate  14  remains a planar surface. Adjustable pin placement through the spring pin adjustment orifices  18  allows the rear axle to be positioned more forward, which can advantageously alter the drive line length as well as allows for a greater clearance between the tire and the back of the rear fender. The bump stop pad  19  is also visible. The traction block  4  is connected to the proximate end of the traction tube assembly  40  by a bolted assembly passing through the traction tube mount  24 , which is a “C” shaped bracket, comprised of two side plates  52  and two traction tube assembly mounting orifices  50 . In this way the height of the traction block  4  can be selected from any of a series of incrementally higher traction blocks  4 . 
         [0021]    In  FIG. 3  the bottom plate  15  of the traction block  4  can be seen. Bottom plate  15  is parallel with the top plate  14  and contains two bottom plate mounting orifices  5 , a second chamfered orifice (not pictured) dimensionally sized to accept a peg adjustment plate  23  such that when the peg adjustment plate  23  is set into the second chamfered orifice the bottom plate  15  remains a planar surface. A peg  17  extends normally from the peg adjustment plate  23 . The peg  17  is dimensionally sized to be received within an axle mounting plate (not shown), which is mechanically affixed to the axle of the vehicle. The peg adjustment plate  23  selected also allows for the rear axle to be positioned more forward. The traction tube mount  24  pivotally connects the traction block  4  via the bracket arm  20  to the outer traction tube  22  via a bushing  36 , and standard bolt, washer, and nut assembly  38 . 
         [0022]    It should be noted that while in the preferred embodiment the top and bottom plates are parallel to one another alternate embodiments could feature angled bottom plates to account for the pinion angle change, which results from higher lifts. 
         [0023]      FIG. 4  illustrates various embodiments of the spring pin adjustment plates  21  and peg adjustment plates  23 . It should be noted that while the preferred embodiment employs the removable and interchangeable plate system for ease of fabrication it is well known by one skilled in the art that orifices to receive the spring pin could be drilled directly into the top of the traction block, and the peg (or pegs) could be affixed directly to the bottom of the traction block. It is known that the removable and interchangeable plate system could be employed on just this traction (spacer) block, without the traction tube assembly, or on any stand alone traction (spacer) block design to enable users to relocate the axle position with respect to the spring assembly. 
         [0024]    Looking at  FIG. 5-7  the telescopic traction tubes can be seen. Inner traction tube  30  fits inside the outer traction tube  22  allowing for telescopic length adjustment of the traction tube assembly  40  (See  FIG. 7 ). This is especially helpful with the various truck box lengths now available. Once the desired length is attained, inner traction tube  30  and outer traction tube  22  are locked together via the clamping coupler  28 . The clamping coupler  28  sets the overall length of the traction tube assembly  40  through a compression fit between the inner tube  30  and the outer tube  22 . This in essence, creates one rigid tube. The clamping coupler  28  frictionally fits over the outer tube  22  at the location where both the inner tube  30  and the outer tube  22  overlap. Once the desired length is set, a hole is drilled through both the outer tube  22  and inner tube  30  so as to align with the existing orifice  29  in the clamping coupler  28 . A bolt (not shown) is tightened so as to deform slightly the inner tube  30  and outer tube  22  diameters such that the outer tube  22  is affixed into the inner tube  30  within the clamping coupler  28  locking the tube length. This is a modified method of achieving a compression fit. This feature makes this system a universal fit for long box or short box trucks. 
         [0025]      FIG. 8 . illustrates the L-shaped frame bracket  34  and the inner traction tube receiving orifice  42 . 
         [0026]      FIG. 9 . is a partial cross-sectional view of the inner traction tube  30  mounted in the frame bracket  34 . The frame bracket  34  mounts to the car frame (not visible)via four bolt, washer, and nut assemblies  44  (only three are visible in  FIG. 9 ). The frame bracket  34  has a generally “L” shaped configuration so as to enable affixation to the bottom and side of the vehicle&#39;s frame rail  32  and to minimize twisting. The distal end of inner traction tube  30  is bolted to the frame bracket  34  by a mounting bolt  48 . The mounting bolt  48  passes through the inner traction tube receiving orifice  42  and threadingly engages with inner tube mounting nut  25  which has been mechanically affixed to (or within, as illustrated in  FIG. 9 ) the distal end of inner traction tube  30 . The receiving orifice  22  is circumferentially lined with a polyurethane bushing  46 . This bushing  46  allows for limited movement of the traction block assembly  2  and also serves to dampen any shock or vibration transmitted to the frame  32  of the vehicle. 
         [0027]    In operation, the user selects a traction block assembly  2  with the desired traction block  4  height, and also selects the desired or appropriate spring pin adjustment plate  21  and peg adjustment plate  23 . 
         [0028]    The U-bolts  10  securing the axle  6  to the spring assembly  8  are removed and any existing spacer blocks between the axle and the spring assembly are removed. The traction block  4  section of the traction block assembly  2  is placed on top of the axle mount pad of the axle  6 , aligning the peg  17  with the positioning orifice in the axle mount pad, and aligning the spring pin adjustment plate orifices  18  with the spring assembly  8  so as to enable the desired horizontal axle location. The U-bolts  10  partially encircle the axle  6  and are inserted through two orifices in the bottom plate  15 , pass around the block, and through the four elongated orifices  16  in the top plate  14 . (Note, that the bottom plate  15  and the top plate  14  overhang the block.) The U-bolt then passes beside the spring assembly  8  and through the upper bump-stop U-bolt bracket orifices  3  in the upper bump-stop U-bolt bracket  12 , where a washer and nut assembly  11  are threadingly engaged on the ends of the U-bolts  10 . This serves so as to constrain the block between the top of the axle mounting pad and the bottom on the spring assembly  8 , as well as constraining the spring assembly  8  between the block&#39;s top plate  14  and the upper bump-stop U-bolt bracket  12 . Frame bracket  34  is bolted to the frame  32 . Now the distance from the frame bracket  34  to the traction block  4  can be measured, and the inner traction tube  30  in slid inside of outer traction tube  22  to the appropriate length. The orifices  50  in the side plates  52  of the traction tube mount  24  are aligned with the bushing  36  of the traction tube mount  24  and a bolt, washer, and nut assembly  38  pivotally connects the traction block  4  via the bracket arm  20  to the outer traction tube  22 . The clamping coupler  28  is slid along the inner traction tube  30  and remains unsecured to the traction tube assembly  40  until the inner traction tube  30  is mounted into the frame bracket  34 . Mounting nut  25  of traction tube  30  is brought in close proximity to the frame bracket  34 . The mounting bolt  48  is inserted through the mounting orifice  42  in the mounting plate bushing  46  and threadingly engaged with the inner tube mounting nut  25 . With the device now sized for the vehicle the clamping coupler  28  is slid down to the end of the outer traction tube  22  at the location where both the inner traction tube  30  and the outer tube  22  overlap and a hole is drilled through both the outer tube  22  and inner tube  30  so as to align with the existing orifice  29  in the clamping coupler  28 . A bolt is tightened so as to deform slightly the inner traction tube  30  and outer traction tube  22  diameters such that the outer traction tube  22  is affixed into the inner tube  30  within the clamping coupler  28  locking the tube length. 
         [0029]    In operation, axle wrap is kept to a minimum as the traction bar&#39;s rigidity counteracts the torque on the axle tube, thus preventing the leaf springs from excessively twisting up into an ‘S’ shape and then snapping back with the resulting loss of traction and wheel hop. Any pivoting motion required between the traction bar assembly  40  and the frame is accommodated by the frame bracket bushing  46  and the traction tube mount bushing  36  located at the proximate and distal ends of the traction bar assembly  40 . 
         [0030]    The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. There are numerous variations and modifications thereof that will also remain readily apparent to others skilled in the art, now that the general principles of the present invention have been disclosed. As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.