Abstract:
A boring apparatus and method for in-situ repair of motor vehicle axles includes a universal mounting plate assembly for attachment to a vehicle axle, both longitudinal (on-axis) and transverse (radial) adjustment assemblies, a bearing assembly and a boring bar and drive assembly having a pair of motor drive units for rotating (speed) and axially advancing (feed) the boring bar. The longitudinal and transverse adjustment assemblies facilitate use of the boring apparatus on a wide variety of vehicle and truck axles from virtually all manufacturers to repair broken axles or damaged bearing surfaces.

Description:
BACKGROUND OF THE INVENTION 
   The invention relates generally to an apparatus and method for repairing vehicle axles and more specifically to an apparatus and method for in-situ repair of broken and damaged axles on motor vehicles, particularly trucks, trailers, and construction equipment. 
   The failure of motor vehicle axle and bearing components in large trucks, tractors, and motor vehicles is a not uncommon event. Notwithstanding preventive maintenance, such failures typically occur while the vehicle is in service and thus away from repair facilities. Not only may the replacement of an axle consume several days, but generally the vehicle must also be towed to a service facility to undertake same. Due to the expense, both of the actual repair and the lost income accompanying the down time of the vehicle, an industry directed to on-site repair of such failed vehicle axle components has developed. 
   One of the earlier patents in this area is U.S. Pat. No. 4,098,029 entitled Axle Grinder which issued to Leo C. Sheits on Jul. 4, 1978. This device resurfaced the bearing surface of a vehicle axle after it had been built up by the addition of weld material thereabout. 
   Another patent of Leo C. Sheits issued Jun. 26, 1984 as U.S. Pat. No. 4,455,732. Here, a fixture is utilized to secure a boring machine to the vehicle axle to enlarge and restore the interior terminal portion of the axle. 
   Another boring device of Leo C. Shiets is disclosed in U.S. Pat. No. 4,820,089. Here, a clamp-on fixture and boring machine facilitates the restoration of front axle steering components. 
   Since these early devices, the demand for improved repair quality has risen steadily, accompanied by a realization that additional features and flexibility would both enhance the functionality of such devices and improve the overall quality of the repair. Improved repair quality, in turn, results in greatly enhanced service life of the repair whereas increased functionality of such machines renders them useable in an even broader range of trailer configurations and manufacturers&#39; products. 
   The following disclosure is directed to an apparatus and method for in-situ repair of vehicle axles which exhibit such improved flexibility and repair quality. 
   BRIEF SUMMARY OF THE INVENTION 
   A boring apparatus and method for in-situ repair of motor vehicle axles includes a universal mounting plate assembly for attachment to a vehicle axle, a mounting or attachment assembly, longitudinal (on-axis) and transverse (radial) adjustment assemblies, a bearing assembly and a boring bar and drive assembly having a pair of motor drive units for rotating (speed) and axially advancing (feed) the boring bar. Both the attachment assembly and the longitudinal and transverse adjustment assemblies facilitate use of the boring apparatus on a wide variety of vehicle and truck axles from virtually all manufacturers to repair broken axles or damaged bearing surfaces. 
   Thus it is an object of the present invention to provide an apparatus for in-situ repair of motor vehicle axles. 
   It is a further object of the present invention to provide a method of repairing motor vehicle axles. 
   It is a still further object of the present invention to provide a boring apparatus having an attachment assembly which is adjustable and secures the apparatus to virtually any vehicle axle. 
   It is a still further object of the present invention to provide a boring apparatus for the in-situ repair of motor vehicle axles having both longitudinal and transverse adjustment assemblies. 
   It is a still further object of the present invention to provide a boring apparatus for in-situ repair of motor vehicle axles having a pair of drive assemblies for rotating and advancing the boring tool. 
   Further objects and advantages of the present invention will become apparent by reference to the following description of the preferred embodiment and appended drawings wherein like reference numbers refer to the same component, element, or feature. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of an assembled apparatus for in-situ repair of motor vehicle axles according to the present invention; 
       FIG. 2  is a perspective view of a longitudinal adjustment assembly on a boring apparatus according to the present invention; 
       FIG. 3  is a perspective view of a transverse adjustment assembly of a boring apparatus according to the present invention; 
       FIG. 4  is a perspective view of a bearing assembly of a boring apparatus according to the present invention; 
       FIG. 5  is a plan view of the boring tool axial drive (feed) assembly of a boring apparatus according to the present invention; 
       FIG. 6  is a plan view of the boring tool rotary drive (speed) assembly of a boring apparatus according to the present invention; 
       FIG. 7  is a diagrammatic view of a first method of axle repair according to the present invention; and 
       FIG. 8  is a diagrammatic view of a second method of axle repair according to the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to  FIG. 1 , a boring apparatus for in-situ repair of motor vehicle axles is illustrated and generally designated by the reference number  10 . The boring apparatus  10  includes an attachment and adapter assembly  12  which secures the apparatus  10  to the brake flange of a motor vehicle axle, as illustrated in  FIG. 7  and as will be described subsequently, and provides longitudinal adjustment, as will also be described subsequently. Attached to the adapter assembly  12  is a radial adjustment assembly  14  which provides orthogonal adjustment, i.e. adjustment along axes normal to one another and disposed in a plane normal to the axis of rotation of the boring tool. A bearing assembly  16  is secured to the adjustment assembly  14  and provides secure rotational support to an elongate boring bar assembly  18 . Finally, the apparatus  10  includes a boring bar drive assembly  20  which rotates and advances or retracts the boring bar assembly  18 . 
   Referring now to  FIG. 2 , the attachment and adapter assembly  12  is illustrated and includes a first annular plate  26  defining a large center aperture or opening  28  and a plurality of curved, stepped slots  32 . The curved slots  32  preferably define circumferential slots  32  having a constant radius from the center of the first annular plate  26 . The slots  32  include a centrally, axially disposed web or lip  34  which defines a shoulder on both sides and which cooperate with the heads  36  of appropriately sized machine bolts  38  to assist their retention within the slots  32 . The bolt heads  36  are sized to be non-rotatably received within the slots  34 . The machine bolts  38  extend through and adjustably retain four generally radially disposed mounting bars, lugs or ears  42 . The mounting lugs or ears  42  include elongate slots  44  through which the machine bolts  38  extend and which facilitate radial as well as circumferential adjustment of the lugs or ears  42  relative to the first annular plate  26 . Conventional nuts  46  may be tightened upon the machine bolts  38  to attach and securely retain the lugs or ears  42  to the first annular plate  26  in a desired position or loosened to facilitate adjustment thereof. 
   Preferably, the lugs or ears  42  include tapered, radially inwardly directed noses  48  which include through openings  52 . The through openings  52  receive threaded fasteners such as bolts and nuts which secure the lugs or ears  42  and correspondingly the first annular plate  26  to a brake flange of a motor vehicle axle, as illustrated in  FIG. 7 . While the assembly  12  has been illustrated with four lugs or ears  42 , it will be appreciated, as evidenced by the eight circumferential slots  32  illustrated in the annular plate shown in  FIG. 2 , that the lugs or ears  42  may be arranged and attached differently than illustrated in  FIG. 3 , or that more or fewer lugs or ears  42  may be utilized with a given first annular plate  26  for a particular repair procedure. 
   Extending away from the face of the first annular plate  26  opposite to the face upon which the lugs or ears  42  reside are a plurality of radially extending bolts  56 . The bolts are non-rotatable by virtue of having, for example, square or hexagonal heads  58  which are received within complementarily configured openings or a continuous slot  62 . It will be appreciated that the bolts  56  may be removed from the first annular plate  26  and replaced by longer or shorter bolts  56  as necessary. Axially disposed about each of the bolts  56  is a spacer  64 . For a given repair project, a set of six tubular spacers  64  having identical axial lengths will be utilized with suitable length elongate bolts  56  to properly axially position the adjustment mechanism  14  and other components of the apparatus  10  at an appropriate, minimum distance from the brake flange in order to ensure optimum operation and the best possible repair. It is acknowledged that a situation may exist where the tubular spacers  64  are not utilized and the elongate bolts  56  are utilized to attach the adjustment mechanism  14  directly to the face of the first annular plate  26  opposite the lugs or ears  42 . Furthermore, it should be understood that analogous structures such as square or polygonal spacers, a single annular spacer of a desired thickness, multiple annular spacers stacked together to provide a desired thickness or partial, e.g., semi-circular spacers, all having appropriate openings for receiving the elongate bolts  56  may be substituted for the tubular spacers  64 . 
   Referring now to  FIG. 3 , the radial adjustment assembly  14  is illustrated and includes a second annular plate  66  having an outside diameter preferably, though not necessarily, equal to the diameter of the first annular plate  26  of the attachment and adapter assembly  12 . The second annular plate  66  includes a large center aperture  68  and defines a plurality, preferably six, through apertures  72  which are arranged and aligned to receive a respective one of the elongate fasteners  56  extending from the first annular plate  26 . An appropriate plurality of threaded fasteners such as conventional nuts  74  may be utilized to selectively secure the assemblies  12  and  14  together. A pair of struts or brackets  78  which may be secured to the second annular plate  66  by welding terminate in a pair of spaced apart rectangular flat plates  82 . The pair of rectangular flat plates  82  define a respective pair of co-planar surfaces  84  which are parallel to the rear face of the second annular plate  66 . Additional brackets or braces  86  extending between the struts or brackets  78  and the rectangular plates  82  may be utilized to ensure the rigidity of the assembly  14 . 
   Arranged in pairs adjacent and secured to the pair of rectangular flat plates  82  are pairs of adjustment assemblies. A first pair of adjustment assemblies  90  each includes a right angle mounting bracket  92  and a threaded adjustment screw  94  having a thumbwheel  96  at one end and a bumper  98  at the opposite end. One of the first pair of adjustment assemblies  90  is secured to one of the pair of rectangular flat plates  82  and the other one of the first pair of adjustment assemblies  90  is second to the other rectangular flat plate  82 . In accordance with conventional practice, clockwise rotational of the thumbwheel  96  advances the threaded shaft  94  and the bumper  98  and vice versa. It will be appreciated that the two threaded shafts  94  of the first adjustment assembly  90  may and are axially aligned and generally intended to work in opposition along a first axis, that is, as one thumbwheel  96 , shaft  94 , and bumper  98  are advanced, the opposite thumbwheel  96 , shaft  94 , and bumper  98  may be retracted, to translate the bearing assembly  16  along a first axis defined by the axis of the two aligned threaded shafts  94 . 
   A second pair of adjustment assemblies  100  is secured to one of the rectangular plates  82  and is oriented along an axis normal to the axis extending between the first pair of adjustment assemblies  90 . The second pair of adjustment assemblies  100  each include a right angle mounting bracket  102  which receives a threaded shaft  104  having a thumbwheel  106  on one end and a bumper  108  on the opposite end. The second pair of adjustment assemblies  100  may, as noted above, be operated in opposition and are generally used to make adjustments generally along a second axis normal to the first axis extending between the first adjustment mechanisms. 
   On the other rectangular plate  82  is a third pair of adjustment assemblies  110 . Like the other pairs of adjustment assemblies  90  and  100 , each of the third pair of adjustment assemblies  110  includes a right angle mounting bracket  112 , a threaded shaft  114 , a thumbwheel  116  and a bumper  118 . The third pair of adjustment assemblies  110  operates along an axis parallel to the second pair of adjustment assemblies  100  and normal to the axis of the first pair of adjustment assemblies  90 . 
   The rectangular plates  82  also include a plurality of threaded apertures  122 . Preferably threaded into the threaded apertures  122  generally near the respective centers of the rectangular plates  82  are a respective pair of threaded studs  124 . Alternatively, the openings  122  may be unthreaded and conventional machine bolts may extend therethrough. The threaded studs  124  are utilized to attach the bearing assembly  16  as illustrated in  FIG. 1 . 
   Referring now to  FIGS. 1 and 4 , the bearing assembly  16  includes a rectangular flat plate  132  preferably having significant thickness, on the order of 0.5 inches to 0.075 inches (12.7 mm to 19.1 mm) which thus defines an edge surface  134 . The rectangular flat plate  132  has a length and width preferably approximately equal to the separations between the pairs of bumpers  98 , and  108  and  118  when the respective pairs of threaded shafts  94 ,  104 , and  114  are in approximately their mid-positions in the pairs of brackets  92 ,  102 , and  112  respectively. As illustrated in  FIG. 1 , the bumpers  98 ,  108 , and  118  engage the edge surface  134  of the flat plate  132  and, by rotation of the adjustment assemblies  90 ,  100 , and  110 , facilitate radial repositioning of the bearing assembly  16  relative to the attachment assembly  14 . The rectangular flat plate  132  includes a plurality of relatively large through apertures  136  which may receive a respective one of the studs  124  extending from the pair of rectangular plates  82 . The through apertures  136  are large relative to the studs  124  such that motion and repositioning of the rectangular flat plate  132  on the surfaces  84  of the rectangular plates  82  may be readily accommodated. Pairs of conventional washers  138  and nuts  142  are utilized to secure the bearing assembly  16  to the adjustment assembly  14  after it has been adjusted to an appropriate radial position, as described below, by the adjustment assemblies  90 ,  100 , and  110 . 
   The bearing assembly  16  includes a pair of axially spaced-apart ball bearing assemblies  144  which are mounted within an elongate cylindrical housing  146 . The cylindrical housing  146  may be secured by welding to the rectangular flat plate  132  and welded gussets  148  may be utilized to reinforce the assembly  16 . The cylindrical housing  146  terminates in a square plate  152  having a face which is accurately parallel to the end face of the rectangular flat plate  132 . The square plate  152  is preferably secured to the cylindrical housing  146  by welding and includes a plurality of through openings  154  which receive a like plurality of machine bolts  156  which attach the boring bar drive assembly  20  to the bearing assembly  16 . 
   Referring now to  FIGS. 1 ,  5  and  6 , the boring bar drive assembly  20  includes a boring bar axial drive (feed) assembly  160 . The axial drive assembly  160  includes a first reversible and variable speed electric motor  162  which drives a chain drive sprocket  164  and, in turn, a drive chain  166 . The drive chain  166  is wrapped about and engages a pair of driven chain sprockets  168  having concentrically disposed internally threaded apertures  170 . Each of the driven chain sprockets  168  receives a respective one of a pair of threaded shafts  172 . The driven chain sprockets  168  are free to rotate but are held captive within a first housing  174  of the boring bar drive assembly  20 . The drive chain  166  also circulates about an idler sprocket  176 . The pair of threaded shafts  172  extend to and are fixedly secured by, for example, lock nuts  178  to a second housing  184 . Thus as the drive chain  166  circulates and rotates the driven chain sprockets  168 , the threaded shafts  172  translate axially relative to the housing  174  and translate the first housing  174  relative to the second housing  184 . 
   A boring bar  180  which forms a portion of the boring bar assembly  18  extends into the first housing  174  and is received within an antifriction bearing such as a ball bearing assembly  182 . The boring bar  180  is freely rotationally received within the housing  174  by virtue of antifriction bearing assembly  182  but it is also restrained against axial motion. Accordingly, when the electric motor  162  is energized, it rotates the driven chain sprockets  168  which translate the first housing  174  along the pair of threaded shafts  172 . Since the end of the boring bar  180  is axially restrained within the housing  174  it, too, moves axially relative to the second housing  184 . 
   Referring now to  FIGS. 1 and 6 , the boring bar drive assembly  20  also includes a boring bar rotating (speed) assembly  190 . The boring bar rotating assembly  190  include a second electric motor  192  which drives, preferably through a right angle drive assembly  194 , a toothed wheel or gear pinion  196 . The gear pinion  196  engages a toothed belt such as a timing belt  198  or a chain which drives a complementarily toothed drive collar  200 . The drive collar  200  is free to rotate but is axially restrained within a housing  202 . The toothed drive collar  200  includes a pair of diametrically opposed axially extending drive keys  204 . The drive keys  204  engage complementary, diametrically opposed, axially extending slots or channels  206  formed in the boring bar  180 . When the electric drive motor  192  is energized, rotational energy is provided to the drive collar  200  which rotates the boring bar  180  and an associated boring or cutting tool  210  attached to the end of the boring bar  180  opposite the boring bar drive assembly  20 . 
   The first electric drive motor  162  and the second electric drive motor  192  are controlled by a control box or unit  212 . The control unit  212  includes a directional switch  214  which selects the direction of rotation of the first electric motor  162  associated with the feed of the boring bar  180  and a variable, preferably rotary control  216  which, in conjunction with a SCR or triac controller, adjusts the speed of the first electric motor  162 . An on-off switch  218  controls energization of the second electric motor  192  which rotates the boring bar  180 . Electrical energy is provided to the control unit  212  through a conventional cordset. 
   Referring now to  FIGS. 1 and 7 , a first repair configuration of a motor vehicle axle  220  is illustrated. The motor vehicle axle  220  includes a brake flange  222  having a plurality through apertures  224  which are offset from and parallel to the axis of the axle  220 . The apertures  224  are utilized to receive a plurality, typically at least four, bolts  226  which extend through the openings  52  in the lugs or ears  42  of the assembly  12 . Suitable nuts  228  are secured and tightened upon the bolts  226  to retain the lugs or ears  42  and all of the associated components of the boring apparatus  10  in place upon the axle  220 . A portion of the axle  220  extending beyond (to the right as illustrated in  FIG. 7 ) of the brake flange  222  has previously been damaged, which has occasioned the repair described herein. Such damage typically occurs near the terminal portion of the axle  220 , away from the brake flange  222 . The damaged portion (not illustrated) has therefore been cut off such that only solid and undamaged material remains between the location of the cut and the brake flange  222 . 
   At this time the boring apparatus  10  is assembled without the boring bar drive assembly  20 . Depending upon the original length of the axle  220  to the right of the brake flange  222 , as illustrated in  FIG. 7 , as well as the length of the remaining (undamaged) axle  220 , suitable length (or thickness) spacers  64  are selected which properly axially locate the boring apparatus  10  relative to the axle  220 , the preferred location being the closest, i.e., shortest (or thinnest) spacers  64  that will locate the boring apparatus  10  closest to the axle  220  while permitting operation and inspection of the boring operation. Setup proceeds by utilizing the boring bar  180  with a dial indicator (not illustrated) disposed at its terminal portion rather than a boring or cutting tool such as the tool  210 . The boring bar  180  and the dial indicator are inserted into the bearing assembly  16  and the thumb wheel adjustments  96 ,  106  and  118  are utilized in conjunction with one another to minimize runout of the dial indicator as it and the boring bar  180  are rotated within the cut off end of the axle  220 , thereby positioning the bearing assembly  16  and specifically the center axis of the bearing assemblies  144  ad the boring bar  180  on, i.e., coincident with, the center axis of the axle  220 . The boring bar  180  having the dial indicator is then removed and the boring bar  180  having a cutting tool  210  is installed in the bearing assembly  16 . Next, the boring bar drive assembly  20  is secured to the bearing assembly  16  by installing and tightening the machine bolts  156 . The boring apparatus  10  is thus assembled into the configuration illustrated in  FIG. 1 . The interior region of the axle  220  is then bored to receive a replacement spindle assembly  230  illustrated in  FIG. 7  or the replacement spindle assembly  250  illustrated in  FIG. 8 . 
   The replacement spindle assembly  230  includes an elongate spindle  232  having a threaded terminal portion  234 , an outer bearing surface  236  and an inner bearing surface  238 . The spindle  232  is received within and secured to a sleeve  240  having an inside diameter just slightly larger than the outside diameter of the corresponding region of the spindle  232 . The spindle  232  and sleeve  240  are preferably secured by weld material  242  fully about its circumference on the ends of the spindle  232  and the sleeve  240  opposite the threaded portion  234  of the spindle  232 . As will be readily appreciated, the outside diameter of the sleeve  240  is just slightly less than the inside diameter of the axle  220  which has just been bored by the boring apparatus  10 . The spindle assembly  230  is then installed in the bored portion of the axle  220 . Upon insertion of the spindle assembly  230  into the axle  220 , a full circumferential weld  244  is emplaced between the sleeve  240  and the axle  220 . Additionally, acuate slots  246  are preferably cut in the wall of the axle  220  and weld material  248  is added therein to secure the rearward portion of the spindle assembly  230  to the axle  220 . 
   Referring now to  FIGS. 1 and 8 , an alternate replacement spindle assembly  250  is illustrated. It should be appreciated that although the spindle assembly  250  is different from the spindle assembly  230  discussed above with regard to  FIG. 7 , the installation, i.e., mounting of the boring apparatus  10  onto the axle  220 , and operation thereof is the same. That is, the ears or lugs  42  are secured to the brake flange  222  of the axle  220  by machines bolts  226  that extend through the openings  52  in the lugs or ears  42  and openings  224  in the brake flange  222  to be secured by nuts  228 . The boring bar  180 , temporarily having a dial indicator secured thereto in place of a cutting or boring tool  210  is inserted into the bearing assembly  16  and the thumb wheels  96 ,  106  and  116  are adjusted in conjunction with one another to center the bearing assembly  16  on the center axis of the axle  220 . The boring bar  18  is then installed with a cutting tool  210  and the drive assembly  20  is activated to bore out the interior of the axle  220  to a desired inside diameter. 
   The spindle assembly  250  includes a spindle  252  having a threaded terminal portion  254 , an outer bearing surface  256  and an inner bearing surface  258 . The largest outside diameter of the spindle  252  which typically corresponds to the diameter of the inner bearing surface  252  is just slightly smaller than the inside diameter of a sleeve  260 . A sleeve  260  is a slightly different configuration than the sleeve  230  discussed above and includes a shaped exterior surface. Once again, however, the sleeve  260  is secured to the spindle  252  by a circumferential weld  262  at the end of the sleeve  252  opposite the threaded terminal portion  254 . The inside diameter of the axle  220  is bored out to a diameter just slightly larger than the outside diameter of the sleeve  260 . The spindle assembly  250  is then inserted into the bored out portion of the axle  220  and a full circumferential weld  264  secures the spindle assembly  252  to the axle  220 . 
   The foregoing disclosure is the best mode devised by the inventor for practicing this invention. It is apparent, however, that apparatus and methods incorporating modifications and variations will be obvious to one skilled in the art of boring machines. Inasmuch as the foregoing disclosure presents the best mode contemplated by the inventor for carrying out the invention and is intended to enable any person skilled in the pertinent art to practice this invention, it should not be construed to be limited thereby but should be construed to include such aforementioned obvious variations and be limited only by the spirit and scope of the following claims.