Abstract:
A roof rack system for a vehicle. The roof rack system including: a roof rack system for a vehicle having a roof, comprising: a roof track having opposite first and second ends; a side track assembly, comprising: a shuttle track having opposite first and second ends; means for removeably attaching the side track assembly to the roof track and for positioning the first end of the shuttle track adjacent to the first end of the roof track; and a shuttle assist assembly mounted to the shuttle track, the shuttle assist assembly including means for exerting force on a shuttle when the shuttle is engaged the shuttle track; and a shuttle slideable in the roof track and in the shuttle track, moveable between the roof track and the shuttle track, and removable from the roof track and from the side track assembly.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a vehicular roof rack system; more specifically, it relates to a highly adaptable vehicular roof rack system with improved loading and unloading capability.  
       BACKGROUND OF THE INVENTION  
       [0002]     Roof racks are conventionally used for temporarily attaching loads such as skis, bicycles, small watercraft, luggage, building materials and other items to the roof of a vehicle for transport. For loading, the article must be lifted to the height of the roof of the vehicle. This can be difficult to accomplish for heavy or unwieldy articles with conventional roof racks currently available. Current designs address only specific load types and inadequately address heavy and unwieldy loads in general.  
         [0003]     Therefore, there is a need for an improved vehicular roof rack system with load type adaptability and improved loading and unloading capability.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention is a system for moving a load from a low position (i.e. a side of a vehicle) to a higher position (a roof of a vehicle) and back again, using a roof track and demountable side tracks that engage the roof track, the side tracks including a lift assist mechanism engaging a shuttle that is free to move in tracks in the side track and the roof track.  
         [0005]     A first aspect of the present invention is a roof rack system for a vehicle having a roof, comprising: a roof track having opposite first and second ends; a side track assembly, comprising: a shuttle track having opposite first and second ends; means for removeably attaching the side track assembly to the roof track and for positioning the first end of the shuttle track adjacent to the first end of the roof track; and a shuttle assist assembly mounted to the shuttle track, the shuttle assist assembly including means for exerting force on a shuttle when the shuttle is engaged in the shuttle track; and a shuttle slideable in the roof track and in the shuttle track, moveable between the roof track and the shuttle track, and removable from the roof track and from the side track assembly.  
         [0006]     A second aspect of the present invention is a roof rack system for a vehicle having a roof, comprising: a hollow roof track having opposite upper and lower walls, opposite first and second sidewalls, opposite first and second ends and a slot in a the upper wall of the roof track extending through the upper wall of the roof track and extending from the first end to the second end of the roof track; the opposite upper and lower walls of the roof track, the opposite first and second sidewalls of the roof track and the slot in the upper wall of the roof track defining a roof track shuttle guide; a side track assembly, comprising: a hollow shuttle track having opposite upper and lower walls, opposite first, second sidewalls and opposite first and second ends and a slot in a the upper wall of the shuttle track extending through the upper wall of the shuttle track and extending from the first end to the second end of the shuttle track; the opposite upper and lower walls of shuttle track, the opposite first and second sidewalls of the shuttle track and the slot in a the upper wall of the shuttle track defining a side track shuttle guide; a pair of brackets fixed to the opposite sidewalls and adjacent to the first end of the track shuttle, the brackets engageable in pins fixed to the first and second sidewalls of and adjacent to the first and second ends of the roof track, the roof track shuttle guide and side track shuttle guide aligned when the pair of brackets are engaged in the pins; and a shuttle assist assembly mounted to the lower sidewall of the shuttle track, the shuttle assist assembly including a bracket, a bracket guide, a slot in the lower sidewall of the shuttle track, and means for exerting force on the bracket, the bracket having a lower portion captured in the bracket guide and an upper portion extending into the side track shuttle guide; and a shuttle engageable in the roof track shuttle guide and the side track shuttle guide, slideable in the roof track shuttle guide and in the side track shuttle guide, and removable from the roof track shuttle guide and the side track shuttle guide. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0007]     The features of the invention are set forth in the appended claims. The invention itself, however, will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:  
         [0008]      FIG. 1  is a side view of a roof rack system according to the present invention in its loading/unloading position;  
         [0009]      FIG. 2A  is a side view of a roof rack system according to the present invention in its loading/unloading position;  
         [0010]      FIG. 2B  is a side view of a roof rack system according to the present invention in its transporting position;  
         [0011]      FIGS. 3A through 3D  are a sequence of side views from the loading/unloading position to the transporting position of a roof rack system according to the present invention;  
         [0012]      FIG. 4A  is a top view and  FIG. 4B  is a side view of a first embodiment of a roof track of a roof rack system according to the present invention;  
         [0013]      FIGS. 4C through 4F  are cross-sectional views through lines  4 C- 4 C,  4 D- 4 D,  4 E- 4 E and  4 F- 4 F respectively of  FIG. 4A ;  
         [0014]      FIG. 5A  is a side view and  FIG. 5B  is a top view of a track engagement end of a removable side track assembly of a roof rack system according to the present invention;  
         [0015]      FIG. 6A  is a cross-sectional side view of a track engagement end of a removable side track assembly of a roof rack system according to the present invention;  
         [0016]      FIG. 6B  is a cross-sectional end view through line  6 B- 6 B of  FIG. 6A ;  
         [0017]      FIG. 6C  is as cross-sectional view illustrating an alternative assist mechanism according to the present invention;  
         [0018]      FIG. 7A  is a side view,  FIG. 7B  is a top view and  FIG. 7C  is an end view of a shuttle assembly of a roof rack system according to a first embodiment of the present invention;  
         [0019]      FIG. 8  is a cross-sectional side view of a lower end of a side track showing an alternative to a shuttle assembly of a roof rack system according to a second embodiment of the present invention;  
         [0020]      FIG. 9A  is a cross-sectional view and  FIG. 9B  is a top schematic view of a cam of a locking mechanism according to the present invention;  
         [0021]      FIG. 10A  is a cross-section through a locking mechanism locked in an un-engaged position according to the present invention;  
         [0022]      FIG. 10B  is a cross-section through a locking mechanism unlocked in an engaged position according to the present invention;  
         [0023]      FIG. 10C  is a cross-section through a locking mechanism in an engaged and locked position according to the present invention;  
         [0024]      FIG. 11  is top view of a pair of carriers arranged to move in unison according to the present invention;  
         [0025]      FIG. 12  is a top view of a multiple roof track roof rack of a roof rack system according to the present invention;  
         [0026]      FIG. 13  is a side view of a roof track of a roof rack system according to a second embodiment the present invention;  
         [0027]      FIG. 14  is a side view of a roof track of a roof rack system according to a third embodiment the present invention;  
         [0028]      FIG. 15A  is a side view and  FIG. 15B  is an end view of a shuttle assembly of a roof rack system according to a third embodiment of the present invention;  
         [0029]      FIG. 16A  is a side view and  FIG. 16B  is an end view of a shuttle assembly of a roof rack system according to a fourth embodiment of the present invention; and  
         [0030]      FIG. 16C , is a partial cross section view of side track assembly of a roof rack for use with the fourth embodiment of the shuttle assembly. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]     A vehicle is defined as a conveyance for moving persons or cargo. Examples of vehicles according to the present invention include, automobiles, vans, trucks, buses and trailers. When an element of the present invention is indicated as mountable on a roof of a vehicle, it should also be understood that the element may be mounted on any relatively horizontal surface of the vehicle such as a hood, bed or body of the vehicle.  
         [0032]      FIG. 1  is a side view of a roof rack system according to the present invention in its loading/unloading position. In  FIG. 1  identical roof rack assemblies  100  each include a roof track  105 , a side track assembly  110  and a carrier assembly  115 . Rack assemblies  100  are illustrated mounted on a roof  120  of a vehicle  125  in the loading/unloading position with an exemplary load in the form of a kayak  130 . Each roof rack assembly  100  includes two or more roof mounts  135  (only one roof mount for each roof rack assembly is illustrated in  FIG. 1 ). Roof mounts  135  include an adjustment feature to move roof tracks  105  toward or away from roof  120  of vehicle  125  in order to bring top surfaces  140  of each roof track  105  into a common plane. Roof mounts  135  include means for securing roof tracks  105  to the top of vehicle  125 . Many means for securing roof mounts to the tops of vehicles are known in the art. In one example, roof mounts  135  may comprise rubber cups that grip the roof and straps that secure to a vehicles roof gutter. In a second example, roof mounts  135  may be adapted to engage and locking mechanism into vehicle roof rails often supplied by the manufacturer of the vehicle.  
         [0033]      FIG. 2A  is a side view of the roof rack system according to the present invention in its loading/unloading position. In  FIG. 2A , a horizontal plane  145  is defined in a flat and level surface of the earth upon which vehicle  125  is disposed. A vertical plane  150  is defined as perpendicular to horizontal plane  145 . When top surface  140  of roof track  105  is parallel to horizontal plane  145 , side track assembly  110  is disposed at an angle A relative to vertical plane  150 . In one example, angle A is between about 10° and about 50°. This makes the angle between roof track  105  and side track assembly between about 100° and about 140° which is an obtuse (greater than 90° but less than 180°) angle. Carrier assembly  115  comprises a cargo adapter  155  removeably mounted to a shuttle assembly  160 . In  FIG. 2A , side track  105  is cutaway in order to illustrate that shuttle assembly  160  is moveably and captively engaged in the side track as is described in more detail infra. In the particular example of  FIG. 2A , cargo adapter  155  is designed for kayak  130 . It is intended that any number of cargo adapters may be designed for specific cargos and may be interchangeably mounted on shuttle assembly  160 .  
         [0034]      FIG. 2B  is a side view of a roof rack system according to the present invention in its transporting position. In  FIG. 2B , roof track  105  is cutaway in order to illustrate that shuttle assembly  160  is moveably and captively engaged in the roof track as will be described in more detail infra. It should be noted, that in  FIG. 2B , side track assembly  110  (see  FIG. 2A ) has been removed.  
         [0035]      FIGS. 3A through 3D  are a sequence of side views from the loading/unloading position to the transporting position of a roof rack system according to the present invention. In  FIGS. 3A, 3B  and  3 C, a hooked flange  165  is attached to side track assembly  110  and a hook  170  formed in an end of the flange engages a flanged pin  175  mounted in a side of roof track  105 . (The flange portion of flanged pin  175  is optional). Hooked flange  165  and flanged pin  170  are adapted to easily attach side track assembly  110  to roof track  105  by hooking the flanged pin with the hook and swinging the roof track in the B direction. Swinging side track in the C direction allows side track assembly  110  to be removed from roof track  105 . This quick attach mechanism is illustrated in  FIGS. 5A and 5B  and described in more detail infra. An optional locking mechanism  180  is mounted on hooked flange  165  and is adapted to engage or disengage a pin capture hole  185  (see  FIG. 3D ) in an end of roof track  105 . Locking mechanism  180  is illustrated in  FIGS. 9A, 9B ,  10 A,  10 B and  10 C and described in more detail infra. Locking mechanism  180  is used to temporarily lock various parts of the roof rack system together as described infra.  
         [0036]     In  FIGS. 3A, 3B ,  3 C and  3 D, roof track  105  or side track assembly  110  or both are shown cutaway in order to illustrate wheels  190  on shuttle assembly  160  captured in shuttle guides (represented by the dashed lines) formed internal to the roof track and the side track assembly. In  FIG. 3A , shuttle assembly  160  is completely within side track assembly  110 . In  FIG. 3B , shuttle assembly  160  is transitioning from side track assembly  110  to roof track  105 . In  FIG. 3C , shuttle assembly  160  is completely within roof track  105 . In  FIG. 3D , side track assembly  110  (see  FIG. 3C ) has been removed.  
         [0037]      FIG. 4A  is a top view and  FIG. 4B  is a side view of a first embodiment of roof track  105  of a roof rack system according to the present invention. In  FIGS. 4A and 4B , roof track  105  is seen to be of the form of a hollow rectangular tube having a top wall  195 A, a bottom wall  195 B and opposite first and second sidewalls  195 C and  195 D and open at opposite ends  200 A to second end  200 B completely through top wall  195 A. A shuttle guide  210  is defined by top wall  195 A, bottom wall  195 B, first sidewall  195 C and second sidewalls  195 D. Slot  205  centered over shuttle guide  210  and is not as wide as shuttle guide  210 . Slot  205  is open to shuttle assembly track  210  and together slot  205  and shuttle guide  210  define a “T” slot. Periodically formed in sidewalls of slot  205  are semicircular notches  215 . Semi-circular notches  215  are adapted to engage a pin of an optional locking mechanism  180  attached to a shuttle assembly as illustrated in  FIGS. 7A, 7B  and  7 C and described infra. A first pair of flanged pins  175  are mounted to and a first pair of pin capture holes  185  are formed in first and second sidewalls  195 C and  195 D adjacent to first end  200 A and a second pair of flanged pins  175  are mounted to and a second pair of pin capture holes  185  are formed in first and second sidewalls  195 C and  195 D adjacent to second end  200 B.  
         [0038]      FIGS. 4C through 4F  are cross-sectional views through lines  4 C- 4 C,  4 D- 4 D,  4 E- 4 E and  4 F- 4 F respectively of  FIG. 4A . In  FIGS. 4C, 4D ,  4 E and  4 F an optional low resistance coating  220  is formed on all interior surfaces of shuttle guide  210 . In one example, low-friction coating  220  is a fluorocarbon polymer. In  FIG. 4C , dashed lines illustrate how wheels  190  of shuttle assembly  160  (only a portion shown) are captured by shuttle guide  210  of roof track  105 .  
         [0039]     Generally, roof tracks  105  are used in pairs, but it is possible to use just one or three or more on the same vehicle. Roof track  105  may be fabricated, for example, from aluminum, steel, plastic, glass filled resin, fiberglass or any other suitable material or combinations thereof.  
         [0040]      FIG. 5A  is a side view and  FIG. 5B  is a top view of a track engagement end of removable side track assembly  110  of a roof rack system according to the present invention. In  FIGS. 5A and 5B , side track assembly  110  includes two flanges  165  (each flange having a hook  170 , see  FIG. 5B ), a shuttle track  225 A and a shuttle assist assembly  225 B mounted under shuttle track  225 A. Within shuttle track  225 A which includes a slot  205 A, is a shuttle guide  210 A. Shuttle guide  210 A is similar to shuttle guide  210  (see  FIGS. 4A and 4B   4 C). Shuttle track  225 A includes a pin capture hole  185 A adapted to engage a pin of optional locking mechanisms on shuttle assembly  160  (see  FIGS. 7A, 7B  and  7 C) when the shuttle assembly is in a lowermost or loading position. Shuttle track  225 A may include semi-circular notches  215 A formed in the sidewalls of slot  205 A to be engaged by another locking mechanism  180  mounted on shuttle assembly  160  (see  FIGS. 7A, 7B  and  7 C)to hold the shuttle assembly in locations on side track assembly  110  other than the loading position. Shuttle assist assembly  225 B includes an access lid  230  in order to gain access to the assist mechanism for adjustment or replacement. While two locking mechanisms  180  are illustrated in  FIG. 5B , one on either of flanges  165 , one or none may be employed.  
         [0041]      FIG. 6A  is a cross-sectional side view of a track engagement end of removable side track assembly  110  of a roof rack system according to the present invention and FIG.  6 B is a cross-sectional end view through line  6 B- 6 B of  FIG. 6A .  FIG. 6A  is taken through line  6 A- 6 A of  FIG. 6B . In  FIGS. 6A and 6B , wheels  190  of shuttle assembly  160  are illustrated engaged in shuttle guide  210 A. Slot  205 A is open to shuttle guide  210 A and together slot  205 A and shuttle guide  210 A define an upper “T” slot. Shuttle assist assembly  225 B includes a clock spring guide  235  under shuttle guide  210 A and a spring chamber  240  under shuttle guide  210 A adjacent to flange  165  (see  FIG. 5A ). Spring chamber  240  houses a drum  245  on which a clock spring  250  is wound, a first end  255  of the clock spring is engaged in drum  245 . Clock spring  250  is fed through clock spring guide  235  and a second end  260  of the clock spring is connected to a bracket  265  engaged in shuttle guide  210 A and extending into spring guide  235  through a slot  270  connecting shuttle guide  210 A and spring guide  235 .  
         [0042]     Clock spring  250  is a retracted coil fitted over drum  245  in its relaxed position. Clock spring  250  comes under tension as it is pulled away from drum  245 . Bracket  265  is automatically pulled up toward drum  245  as spring  250  recoils on the drum and the tension on the spring decreases. Drum  245  is locked in position and does not rotate as clock spring  250  coils and uncoils as bracket  265  is moved. As bracket  265  is pulled down by the user pulling on shuttle assembly  160 , the bracket is pulled away from the drum and the tension on spring  250  increases. Optional bumpers  275  are provided on shuttle assembly  160  to prevent wheels  190  from contacting bracket  265 . Thus, power assist in moving heavy loads from the load position (see  FIG. 2A ) to the transport position (see  FIG. 2B ) is provided. In one example, clock spring  250  provides about 5 to about 50 foot-pounds of assist force. Bracket  265  may include an optional flange  267  to engage clock spring guide  235 .  
         [0043]     Optionally, when bracket  265  is pulled as close as possible to drum  245 , clock spring  250  may be removed from drum  245  and replaced in the field by the user with a different spring having a different assist force. In an alternative embodiment, clock spring  250  may be replaced with a coil spring, an elastomer strap or elastomer cord. In an alternative embodiment drum  245  may be adapted to be adjustable in order to increase or decrease the tension on clock spring  250  (or the elastomer strap or cord). In an alternative embodiment clock spring  250  and drum  245  may be replaced by a reversible direction motor and appropriate gearing.  
         [0044]      FIG. 6C  is as cross-sectional view illustrating an alternative assist mechanism according to the present invention. In  FIG. 6C , a hydraulic cylinder  271  with a piston  272 , such as a gas strut and a recursive bracket  273  is attached to cylinder  272  and the assembly fitted into guide  235 . An end  274  of recursive bracket  273  projects into shuttle guide  210 A.  
         [0045]     Side track assembly  110  may be fabricated, for example, from aluminum, steel, plastic, glass filled resin, fiberglass, any other suitable material or combinations thereof.  
         [0046]      FIG. 7A  is a side view,  FIG. 7B  is a top view and.  FIG. 7C  is an end view of shuttle assembly  160  of a roof rack system according to a first embodiment of the present invention. In  FIGS. 7A and 7B , shuttle assembly  160  includes wheels  190  mounted on axles  280 , a mounting plate  285 , struts  290  connecting mounting plate  285  to axles  280 , optional bumpers  275  connected to struts  275  by brackets  295  and optional locking mechanisms  180  are connected to struts  290  by brackets  300 . Turning to  FIG. 7B , mounting plate  285  includes a centrally located optional clearance opening  305  and a multiplicity of attachment slots  310  which extend through the thickness of mounting plate  285 . The purpose of clearance opening  305  is to allow quick turning (in terms of turning through an angle) as shuttle assembly  160  transitions from side track assembly  110  to roof track  105  (see  FIG. 3B ). The purpose of attachment slots  305  is to allow temporary mounting of any number of different cargo adapters to shuttle assembly  160 . See, for example, a cargo adapter  155  in  FIG. 2A .  
         [0047]     Shuttle assembly  160  may be fabricated, for example, from aluminum, steel, plastic, glass filled resin, fiberglass, any other suitable material or combinations thereof. Wheels  190  may be fabricated, for example, from aluminum, steel, plastic, rubber, polyurethane or fluoro-carbon polymers. Bumpers  275  may be fabricated, for example, rubber, polyurethane or fluorocarbon polymers.  
         [0048]      FIG. 8  is a cross-sectional side view of a lower end of a side track assembly  110  showing an alternative to a shuttle assembly according to a second embodiment of the roof rack system of the present invention. In  FIG. 8 , a load slider  315  includes a handle  320  connected to a bearing  325  (or integrally formed with) which is engaged in shuttle guide  210 A and optional locking mechanism  180 . Load slider  315  is moved along shuttle guide  210 A the same as shuttle assembly  160  illustrated in  FIG. 6A  and described supra. If bearing  325  is small enough, load slider may be slid into roof rack  105  similarly to shuttle  160  (see  FIGS. 3A, 3B ,  3 C and  3 D).  
         [0049]      FIG. 9A  is a cross-sectional view and  FIG. 9B  is a top schematic view of a cam  330  of locking mechanism  180  of  FIGS. 5B, 7A  and  8 . Slot A is located a furthest distance from a bottom  335  of cam  330 . Slot B is open to bottom  335  of cam  330 . Slot C is located a distance part way between Slot A and bottom  335  of cam  330 . Slot A is a locked pin up position or locked and not engaged position of locking mechanism  180 . Slot B is an automatic pin engage position or auto-engage position of the locking mechanism  180 . Slot C is a locked pin down position or locked and engaged position of the locking mechanism  180 .  
         [0050]      FIG. 10A  is a cross-section through locking mechanism  180  locked in an un-engaged position according to the present invention. In  FIG. 10A , locking mechanism  180  includes a knob  340 , cam  330 , a pin  345  and a cam follower  350  attached to or integral with pin  345 . A spring  355  is positioned between cam  330  and pin  345  so as to always exert outward force on the pin. Knob  340  is fixed to pin  345  so the pin rotates when the knob is rotated and moves in and out and the knob moves in and out as cam follower  350  follows Slot A, Slot B and Slot C. Cam  330  is fixedly mounted to a mounting surface plate  360 . Mounting plate  360  comprises either flange  165  (see  FIG. 5A ) or bracket  300  (see  FIG. 7B ).  
         [0051]     In  FIG. 10A , locking mechanism  180  is in its locked and not engaged position and a bottom surface  365  is flush with (or recessed below) a bottom surface  370  of mounting plate  360 . In this position, pin  345  cannot move away from cam  330 .  
         [0052]      FIG. 10B  is a cross-section through locking mechanism  180  unlocked in an engaged position according to the present invention. In  FIG. 10B , locking mechanism  180  is in its auto-engage position and a bottom surface  365  extends a distance D 1  past bottom surface  370  of mounting plate  360 . In this position, pin  345  automatically moves away from cam  330  when positioned over an opening, for example opening  185  and notches  215  of top rack.  105  of  FIGS. 4A and 4B  or opening  185 A and notches  215 A of a side track assembly  110  of  FIG. 5B .  
         [0053]      FIG. 10C  is a cross-section through locking mechanism  180  in an engaged and locked position according to the present invention. In  FIG. 10C , locking mechanism  180  is in its locked and engaged position and a bottom surface  365  is extends a distance D 2  past bottom surface  370  of mounting plate  360 . In this position, pin  345  cannot move toward cam  330 . D 2  is less than D 1 .  
         [0054]      FIG. 11  is top view of a pair of shuttle assemblies  160  arranged to move in unison of a roof rack system according to the present invention. In  FIG. 11 , a connector  375  includes two attachment plates  385  connected to each other by a strut  380 . Attachment plates  385  include openings  390  that align with opening  305  in mounting plate  285  of shuttle assembly  160  and mounting holes  395  that align with attachment slots  310  in mounting plate  285 . Two roof tracks and two side track assemblies are required in this configuration.  
         [0055]      FIG. 12  is a top view of a multiple roof track roof rack system according to the present invention. In  FIG. 12 , three or more roof tracks  105  are mounted to cross-bars  400 . Cross-bars  400  may be mounted to the roof by any number of methods known in the art. In one example, cross-bars  400  are fabricated from box beam or “U” channel.  
         [0056]      FIG. 13  is a side view of a roof track  105 A of a roof rack system according to a second embodiment the present invention. In  FIG. 13 , roof track  105 A is similar to roof track  105  of  FIG. 4B  except that the roof track is curved away from the vehicle top. A central portion  405  of roof track  105 A is curved away from distal ends  200 C and  200 D.  
         [0057]     It should be noted that side track assemblies  110  (see  FIG. 5A ) may be attached to either end  200 A or  200 B of roof track  105  of  FIG. 4B  or either end  200 C or  200 D of roof track  105 A depending from which side of the vehicle loading is to be performed and from which side of the vehicle unloading is to be performed from. Loading and unloading can be performed from either side of the vehicle and loading does not need to be performed from the same side of the vehicle as unloading because the side track assemblies are removable and universally attachable.  
         [0058]      FIG. 14  is a side view of a roof track  105 B of a roof rack system according to a third embodiment the present invention. In  FIG. 14 , roof track  105 B is similar to roof track  105  of  FIG. 4B  except that roof track  105 B has only one end (a first end  205 E) to which a side track assembly  110  (see  FIG. 5A ) may be mounted. A second end  200 F may be closed so as to prevent a shuttle from being removed or being pushed out of roof track  105 B. Also roof track  105 B may mounted to any conventional roof rack  405 .  
         [0059]      FIG. 15A  is a side view and  FIG. 15B  is an end view of a shuttle assembly  160 A of a roof rack system according to a third embodiment of the present invention. In  FIGS. 15A and 15B , shuttle assembly  160 A is similar to shuttle assembly  160  of  FIGS. 7A, 7B  and  7 C except that wheels  190  and axels  280  (see  FIG. 7A ) are replaced with non-rotatable pins  410  connected to strut  290  and bumpers  275  are connected directly to pins  410 .  
         [0060]      FIG. 16A  is a side view and  FIG. 16B  is an end view of a shuttle assembly  160 B of a roof rack system according to a fourth embodiment of the present invention. In  FIGS. 16A and 16B , shuttle assembly  160 B is similar to shuttle assembly  160  of  FIGS. 7A, 7B  and  7 C except that wheels  190  (see  FIG. 7A ) are replaced with toothed wheels (or pinions)  415 .  
         [0061]      FIG. 16C , is a partial cross section view of side track assembly  110 A of a roof rack of a roof rack system for use with the fourth embodiment of the shuttle assembly. In  FIG. 16C , side track assembly  110 A is similar to side track assembly  110  of  FIG. 6A  except shuttle track  225 B includes toothed track (or rack)  420 . Teeth on toothed wheel (pinion)  415  are adapted to mesh with teeth toothed track  420 . Similarly, toothed tracks (racks) may be mounted on bottom wall  195 B top track  105  (see  FIG. 4B ). Spring  250  is shown in clock spring guide  235 .  
         [0062]     Thus, the present invention provides an improved vehicular roof rack system with load type adaptability and improved loading and unloading capability.  
         [0063]     Additionally, the present invention is capable of being mounted to any relatively horizontal surface for example, a table or bench top, a deck or the roof of a shed in order to assist moving loads from the side of the table or bench top, deck or shed to the table or bench top, deck surface or shed roof, respectively, and back again.  
         [0064]     The description of the embodiments of the present invention is given above for the understanding of the present invention. It will be understood that the invention is not limited to the particular embodiments described herein, but is capable of various modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, it is intended that the following claims cover all such modifications and changes as fall within the true spirit and scope of the invention.