Abstract:
A removable underlift T-bar support accessory for tow trucks with underlift T-bars for lifting and towing a fifth wheel trailer or a goose neck trailer. The underlift T-bar comprises a boom connected to a crossbar having two legs. The accessory mounts on the underlift T-bar and provides a fifth wheel hitch assembly or a hitch ball at an appropriate working elevation thereby enabling the lifting and towing of a fifth wheel trailer or a goose neck trailer by a tow truck equipped with an underlift T-bar.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     REFERENCE TO A MICROFICHE APPENDIX 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a underlift T-bar support accessory by which a tow truck operator may easily and reversibly modify an underlift T-bar of a tow truck into an underlift T-bar equipped with a convenient fifth wheel hitch assembly for lifting and towing of fifth wheel hitch trailers. The invention also optionally, but preferably, provides a hitch ball for use with gooseneck trailers that require a hitch ball on the towing vehicle. 
     2. Description of Related Art 
     A number of devices exist for mounting a fifth wheel hitch in a pickup truck bed for towing a fifth wheel hitch trailer including HARRIS, U.S. Pat. No. 4,824,134 issued Apr. 25, 1989; CHAMBERS, U.S. Pat. No. 4,960,288 issued Oct. 2, 1990; and LINDENMAN, U.S. Pat. No. 5,509,682 issued Apr. 23, 1996. These devices are not suitable for use with underlift T-bars. 
     At least one fifth wheel hitch apparatus distributed by Miller Industries Towing Equipment Inc. of Ooltewah, Tennessee exists that may be used with tow trucks with a rear mounted underlift T-bar. The Miller device is massive, heavy, and cumbersome and provides little elevation to its centrally disposed fifth wheel hitch above the crossbar of the underlift T-bar. The Miller device is assembled on the crossbar of the underlift T-bar by sliding a sleeve onto each of the two free ends of the crossbar, each sleeve having an ear extending to the rear of the crossbar, each ear having a receiving aperture dimensioned to receive a vertical mounting stud of a central assembly, by mounting a central assembly having two vertical mounting studs to the sleeves from above by inserting the two studs into the receiving apertures, and by securing the studs in the ears by inserting locking pins in radial-through holes in the studs below the ears. The central assembly includes a centrally disposed fifth wheel hitch for receiving a kingpin of a fifth wheel trailer. When using the Miller apparatus, the operator has to reach under the trailer to be towed to insert a keeper pin in the hitch to secure the kingpin. 
     HILL, U.S. Pat. No. 5,607,279 issued Mar. 4, 1997, discloses a towing lift accessory for mounting a cable sheave to the retractable leg of an underlift hoist of a winch equipped flat bed tow truck. The elements of the lift accessory and its method of use require retraction of the leg to secure the lift accessory to the leg of the underlift hoist. The lift accessory provides a means for elevating and stabilizing the sheave for use with a cable running from a winch on the tow truck to a vehicle or other load to be retrieved. Hill also provides for a hitch socket member for receiving a conventional trailer hitch accessory. 
     BRIEF SUMMARY OF THE INVENTION 
     Towing vehicles, commonly tow trucks, often have a rear mounted hydraulically actuated underlift T-bar. The underlift T-bar comprises a boom aligned with the longitudinal axis of the tow truck connected to a crossbar proximate its middle point. The crossbar has a first leg and a second leg. 
     Many of the currently used underlift T-bars have booms that can be telescopically extended and retracted and many of the underlift T-bars have a limited range of vertical lifting motion that is insufficient for the lifting and towing of fifth wheel trailers. 
     A principal objective of this invention is to provide a novel, improved, and removable fifth wheel hitch assembly support accessory that is relatively lightweight, compact, simple, and low-maintenance, that is relatively inexpensive to manufacture, and that over a long service life provides reliable performance. The present invention provides for easy and reversible modification of an underlift T-bar of a tow truck to allow the lifting and towing of a fifth wheel trailer. The invention also provides an elevated hitch ball to an underlift T-bar, accessible for easy use for lifting and towing a gooseneck trailer. 
     The accessory includes a novel frame easily mounted to the boom and legs of an underlift T-bar. Then either a fifth wheel hitch assembly or a hitch ball is coupled to the frame. Then either a fifth wheel trailer or a goose neck trailer is coupled to the hitch assembly or hitch ball for lifting and towing. The frame provides the hitch assembly or hitch ball at an appropriate working elevation. In the preferred embodiment, the frame provides elevation of the fifth wheel hitch assembly approximately two feet above the central axis of the crossbar of the underlift T-bar. The frame provides elevation of the hitch ball approximately one and a half feet above the central axis of the crossbar of the underlift T-bar. The elevation provided by the frame allows an underlift T-bar that has limited range of vertical lifting motion increased capability to lift and tow a fifth wheel trailer or a goose neck trailer. 
     The frame includes two leg-straddling brackets and one boom-straddling bracket whereby the frame is releasably mounted to the boom and the two legs of the crossbar of the underlift T-bar. The two leg-straddling brackets are spaced from each other equidistant from the middle point of the crossbar and each is dimensioned to straddle and extend downward on both sides of a leg of the crossbar and downward below the leg. The boom-straddling bracket is dimensioned to straddle and extend downward on both sides of the boom and downward below the boom. Each bracket cooperates with locking means to encircle the corresponding boom or leg. The locking means may include releasable slidably received locking pins, push-pull pins, or locking bolts that are received in a pair of cooperating apertures in each of the brackets. Preferably the locking pins are secured relative to the brackets by spring clips, hair-pin clips, lynch pin clips, or cotter pins through radial-through holes in the locking pins. If locking bolts are used, they can be secured with locking nuts. 
     The frame may include three bracket shims for adjusting the dimensions of the brackets relative to the boom and legs of the specific underlift T-bar being modified. The shims allow the frame when dimensioned to fit an underlift T-bar with a larger boom or larger legs to be adjusted for use with an underlift T-bar with a smaller boom or smaller legs. 
     Each leg-straddling bracket is joined to a vertical support, the two vertical supports are connected to opposite ends of a horizontal crosspiece. The supports and the crosspiece form a figure H. Preferably, a hitch ball is releasably mounted in an appropriate opening in the crosspiece. 
     The boom-straddling bracket is joined to an angled member, the angled member is joined to the crosspiece proximate its midpoint. The vertical supports at their upper ends are joined to yokes that are adapted and dimensioned to cooperate with two pintle pins of a fifth wheel hitch assembly; whereby, the hitch assembly may be operatively coupled and decoupled from the yokes. Each yoke may receive and operatively retain a pintle pin of the fifth wheel hitch assembly. Each yoke has a pair of cooperating holes for the insertion of retaining means to secure a pintle pin relative to the yoke. The retaining means may include releasable slidably received retaining pins, push-pull pins, or retaining bolts that are received in the cooperating holes. Preferably the retaining pins are secured relative to the yokes by spring clips, hair-pin clips, lynch pin clips, or cotter pins through radial-through holes in the retaining pins. If retaining bolts are used, they can be secured with locking nuts. 
     Another prime object of the accessory is to increase the capability of a tow truck equipped with an underlift T-bar having a telescoping boom to respond to a towing situation that involves a disabled tow vehicle towing a fifth wheel hitch trailer or a goose neck trailer. Often such a truck is also equipped with a tiltable, extendable flat bed for carrying a disabled vehicle. Nominal use of the accessory with such a truck regarding a fifth wheel hitch trailer will allow a tow truck operator to perform the following steps: loading on the bed a disabled tow vehicle even longer than the bed, extending the boom to the rear as necessary to provide clearance from the disabled tow vehicle, affixing and locking the frame to the boom and legs of the crossbar, coupling a fifth wheel hitch assembly to the frame, coupling a fifth wheel trailer to the hitch assembly, and then lifting and towing the fifth wheel trailer. Nominal use of the accessory with such a truck regarding a goose neck trailer will allow a tow truck operator to perform the following steps: loading on the bed a disabled tow vehicle even longer than the bed, extending the boom to the rear as necessary to provide clearance from the disabled tow vehicle, affixing and locking the frame to the boom and legs of the crossbar, coupling a goose neck trailer to the hitch ball, and then lifting and towing the goose neck trailer. 
     Another object is to provide an underlift T-bar support accessory that does not require permanent or prior structural modification of the underlift T-bar. An advantage of the present invention is that it provides a robust, underlift T-bar support accessory proximate the crossbar of the underlift T-bar. When the accessory is affixed and locked to an underlift T-bar having a telescoping boom, the accessory can be moved rearward as the boom is extended and moved forward as the boom is retracted. 
     Another object is to promote tow truck operator safety by providing a lightweight fifth wheel hitch assembly support accessory for use with an underlift T-bar that avoids the operator getting under the boom to attach the accessory. Use of the accessory also avoids the operator reaching under or getting under a fifth wheel trailer to secure the trailer to the fifth wheel hitch assembly. 
     The present invention avoids a major disadvantage of a fifth wheel hitch assembly attached to a bed of a tow truck. When a fifth wheel hitch assembly is attached to the bed of the tow truck, the bed is thereby often made unavailable for other purposes including carrying a disabled vehicle. The accessory permits convenient lifting and towing of a fifth wheel trailer without interfering with or precluding use of the bed of the tow truck. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is an oblique perspective view of the rear of a tow truck equipped with an underlift T-bar having attached thereto an underlift T-bar support accessory including a fifth wheel hitch assembly. 
     FIG. 2 is a side elevational view of the underlift T-bar support accessory shown in FIG.  1 . 
     FIG. 3 is an oblique, partially exploded, perspective view of the underlift T-bar support accessory. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1, the present invention is novel and provides an underlift T-bar support accessory  8  having a frame  10  especially suited for mounting on a towing vehicle preferably a tow truck  12 . The tow truck  12  preferably includes an underlift T-bar  14  that extends from the back of the tow truck. The underlift T-bar  14  can be of many alternative designs known in the art. Preferably, the underlift T-bar  14  is hydraulically actuated and can be raised and lowered vertically and has a telescoping boom  16  connected to a crossbar  18  at an approximate middle point  20  of the crossbar. The telescoping boom  16  is longitudinally extendable and may be locked in variable positions of extension from fully retracted to fully extended. The crossbar  18  has a first leg  22  and a second leg  24 . A method of using the accessory  8  with an underlift T-bar  14  provides for lifting and towing of a fifth wheel trailer (not shown). An alternative method of using the accessory  8  with an underlift T-bar  14  provides for lifting and towing of a goose neck trailer (not shown). 
     Referring to FIG. 1, the frame  10  is releasably affixed and locked to the boom  16  and the first leg  22  and the second leg  24  of the crossbar  18  of the tow truck  12 . The frame  10  includes a first leg-straddling bracket  26  and a second leg-straddling bracket  28 . Alternatively, the first leg-straddling bracket  26  and the second leg-straddling bracket  28  are together referred to as the leg-straddling brackets  26  and  28 . The leg-straddling brackets  26  and  28  are spaced from each other equidistant from the middle point of the crossbar  18  and respectively extend downward, around, and downward below the first leg  22  and the second leg  24  of the crossbar  18 . The first leg  22  of the crossbar  18  releasably receives the first leg-straddling bracket  26 . Correspondingly, the second leg  24  releasably receives the second leg-straddling bracket  28 . 
     Referring to FIGS. 1,  2 , and  3 , the frame  10  further includes a boom-straddling bracket  30 . The boom  16  releasably receives the boom-straddling bracket  30 . The boom-straddling bracket  30  extends downward, around, and downward below the boom  16 . 
     The leg-straddling brackets  26  and  28  and the boom-straddling bracket  30  each include a bracket locking means  32 ,  34 , and  36  to releasably affix and lock respectively each of the leg-straddling brackets  26  and  28  to the first leg  22  and the second leg  24  of the crossbar  18  and the boom-straddling bracket  30  to the boom  16 . The bracket locking means  32 ,  34 , and  36  shown each include a locking pin  38  slidably received in a pair of cooperating apertures  39  in each of the leg-straddling brackets  26  and  28  and the boom-straddling bracket  30 . Each locking pin  38  may be held in position by a spring clip  40 . The leg-straddling brackets  26  and  28  and the bracket locking means  32  and  34  respectively encircle the first leg  22  and the second leg  24  of the crossbar  18 . The boom-straddling bracket  30  and the bracket locking means  36  encircle the boom  16 . 
     The frame  10  also includes a first vertical support  42  and a second vertical support  44 . The first vertical support  42  is joined to the first leg-straddling bracket  26  and depends vertically from the leg-straddling bracket  26 . Correspondingly, the second vertical support  44  is joined to the second leg-straddling bracket  28  and depends vertically from the leg-straddling bracket  28 . Alternatively, the first vertical support  42  and the second vertical support  44  are together referred to as the vertical supports  42  and  44 . The vertical supports  42  and  44  are joined respectively to opposite ends  46  and  48  of a horizontal crosspiece  50 . In the preferred embodiment, the vertical supports  42  and  44  are parallel to one another and the crosspiece  50  is welded between them forming a figure H. 
     The frame  10  further includes an angled member  52 . The angled member  52  is joined to the boom-straddling bracket  30 . The angled member  52  depends upwardly and rearwardly from the boom-straddling bracket  30  and is connected to the crosspiece  50  proximate its midpoint  54 . 
     Respectively, each vertical support  42  and  44  has an upper end  56  and  58 . Each upper end  56  and  58  is joined respectively to a yoke  60  and  62 . Each yoke  60  and  62  is U-shaped and is dimensioned to receive respectively a pintle pin  64  and  66  of a fifth wheel hitch assembly  68 . Each yoke  60  and  62  has a pair of cooperating holes  69  for the insertion of a retaining pin  70  that may be held in position by a spring clip  40 . 
     The accessory  8  includes a fifth wheel hitch assembly  68 . Referring to FIG. 3, the hitch assembly  68  comprises a draw-bar member  72  having a centrally disposed locking hitch  74  controlled by a control handle  76  and a pair of pintle pins  64  and  66  projecting respectively from opposite sides  78  and  80  of the draw-bar member  72 . Preferably the pintle pins  64  and  66  are coaxial. 
     The hitch assembly  68  can be pivotably and operatively connected to the yokes  60  and  62  via pintle pin retaining means  82  and  84  that retain pintle pins  64  and  66  after the pintle pins  64  and  66  are respectively received by the yokes  60  and  62 . As depicted in FIGS. 1 and 3, the pintle pin retaining means  82  and  84  shown each include a retaining pin  70  that is slidably received in a pair of cooperating holes  69  formed in each yoke  60  and  62 . Each retaining pin  70  may be held in position by a spring clip  40 . 
     The hitch assembly  68 , in a manner known in the art, may be releasably locked by means of the control handle  76  to secure a king pin (not shown) of a trailer to be towed (not shown). 
     The leg-straddling brackets  26  and  28 , the boom-straddling bracket  30 , the vertical supports  42  and  44 , the angled member  52 , the horizontal crosspiece  60 , and the yokes  60  and  62  can be fabricated from structural steel. The brackets  26 ,  28 , and  30  can be formed of appropriate sized channel or in an exemplary configuration fabricated from L-shaped pieces of steel welded together to form a channel-shaped bracket. The vertical supports  42  and  44  can be formed of two-inch by three-inch structural steel tubing each having a length of approximately 24 inches each welded respectively to a leg-straddling bracket  26  and  28 . The angled member  52  can be formed of two-inch by three-inch structural steel tubing having a length of approximately 22 inches. The angled member  52  is beveled for welding and is welded to the boom-straddling bracket  30  at a preferred angle of approximately  45  degrees from the horizontal and is beveled at the other end for welding and is welded to the crosspiece  50 . The yokes  60  and  62  can be formed from two-inch by ¼-inch flat steel bars each having a length of approximately five inches. The yokes  60  and  62  preferably are welded respectively to upper ends  56  and  58 . The crosspiece  50  preferably can be formed from three-inch steel angle iron having rearwardly and downwardly extending flanges and having a length of approximately 18½ inches. The crosspiece  50  may alternatively be formed from solid steel bar or round, square, or rectangular steel tubing. The opposite ends  46  and  48  of the crosspiece  50  are welded respectively to vertical supports  42  and  44 . 
     The locking pins  38  preferably are ⅝-inch pins of suitable length to extend through and beyond the pair of cooperating apertures  39  in the brackets  26 ,  28 , and  30  to enable securing of the locking pins  38  by spring clips  40 . The retaining pins  70  preferably are ⅜ inch pins of suitable length to extend through and beyond the pair of cooperating holes  69  in the yokes  60  and  62  to enable securing of the retaining pins  70  by spring clips  40 . Preferably, the pins  38  and  70  are made of cold-rolled steel and the spring clips  40  are made of spring steel. Preferably, the pins  38  have a double head as shown in FIG. 3 to facilitate insertion and removal of the pin. 
     The fifth wheel hitch assembly  68  can be a RBW INDUSTRIES, INC., model: LR-1001 crossbar hitch (LI&#39;L ROCK&#39;R 5 th  Wheel Hitch) with the annular terminal flanges (not shown) ground off so that the pintle pins  64  and  66  are cylindrical in shape. 
     The support accessory  8  can be conveniently used with various underlift T-bars available from Miller Industries Towing Equipment Inc., Jerr-Dan Underlifts, NO-Mar, Dynamic, and Kilar. Preferably, the underlift T-bar  14  includes a telescoping boom  16  that is longitudinally extendable and may be locked in variable positions of extension from fully retracted to fully extended. 
     The frame  10  may also include a hitch ball  86  releasably mounted in an appropriate opening  88  in the crosspiece  50 . The hitch ball  86  can be a conventional hitch ball which may be of any of the various conventional, available sizes, but preferably having a 1-inch threaded shank. 
     Referring to FIG. 3, the frame  10  may include two leg-bracket shims  90  having a plurality of alignment tabs  92  and one boom-bracket shim  94  having a plurality of alignment tabs  92  for adjusting the dimensions of the brackets  26 ,  28 , and  30  relative respectively to the first leg  22  and the second leg  24  of the crossbar  18  and to the boom  16  of the specific underlift T-bar  14  being modified. The shims  90  and  94  are slidably received within brackets  26 ,  28 , and  30  and allow the frame  10  when dimensioned to fit an underlift T-bar  14  with a larger boom  16  or larger crossbar  18  to be adjusted for use with an underlift T-bar with a smaller boom or smaller crossbar. The shims  90  and  94  can be fabricated from structural steel and can be formed of appropriate sized channel or in an exemplary configuration fabricated from L-shaped pieces of steel welded together to form a channel-shaped shim. 
     From the preceding, it should be apparent that the present invention provides a new underlift T-bar support accessory and methods that allow for convenient, easy modification of an underlift T-bar of a tow truck to permit the lifting and towing of fifth wheel trailers or goose neck trailers. 
     The preceding description and exposition of a preferred embodiment of the invention is presented for purposes of illustration and enabling disclosure. It is neither intended to be exhaustive nor to limit the invention to the precise form disclosed. Modifications or variations in the invention in light of the above teachings that are obvious to one of ordinary skill in the art are considered within the scope of the invention as determined by the appended claims when interpreted to the breath to which they are fairly, legitimately and equitably entitled.