Abstract:
A four-wheeled recreational vehicle in the form of a go-cart having an open body without doors or windows. The body is formed from interconnected tubular members to define a chassis and frame. The vehicle includes a front suspension having V-shaped, parallel upper and lower control members including forward and rear control arms. The forward control arms are substantially perpendicular to the chassis centerline and the rear control arms incline inwardly and rearwardly from the front wheels. Greater vertical front wheel travel is provided for improved ride comfort and stability over rough terrain. The accelerator and brake pedals are placed closer to the front wheel pivot axis for greater legroom.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the benefit of U.S. Provisional Application Ser. No. 60/634,158, filed on Dec. 8, 2004. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an off-road, four-wheeled recreational vehicle of the type sometimes referred to as a go-cart. More particularly, the present invention relates to an improved go-cart having a relatively short wheelbase, a compact overall structure, good handling and maneuverability, along with greater legroom than is available in many currently available compact go-carts. 
   2. Description of the Related Art 
   Go-carts of various configurations are known. Generally, such vehicles have a substantially open, tubular frame structure, three or four wheels, and one or two seats. Known vehicles of that type have either a short vertical travel front suspension system for a low-slung, generally shorter and narrower vehicle, or a high vertical travel front suspension system for a taller, generally longer and wider vehicle. Greater suspension travel is desirable to provide improved ride comfort and stability on rough terrain. Additionally, the shorter and narrower vehicles generally have limited legroom, which limits the size of the operator who can comfortably operate the vehicle, thereby limiting the potential market for it. On the other hand, the longer and wider vehicles are generally too large for convenient and economical shipment at a sufficient vehicle density in standard cargo containers of the type utilized in over-ocean shipments. Such vehicles also require larger storage spaces in user-owned facilities, such as personal garages. 
   There is therefore a need for a compact go-cart that accommodates two persons and that has a suspension system that enables a higher degree of front wheel vertical travel for improved off-road performance, improved maneuverability, and improved occupant comfort over widely varying terrain surfaces. Additionally, it is desirable to provide a compact go-cart structure that has a relatively short wheelbase while at the same time providing sufficient front legroom to comfortably accommodate a wide range of drivers of different sizes, from youths to adults. The present invention satisfies those needs and desires. 
   SUMMARY OF THE INVENTION 
   Briefly stated, in accordance with one aspect of the present invention, a compact, four-wheel, off-road, recreational vehicle is provided. The vehicle has a tubular frame, independent front suspension, rear-engine, rear-wheel drive, and seating to accommodate two persons. The front suspension includes generally V-shaped upper and lower control arms that have a length that permits greater vertical front wheel travel. The vehicle length and width are minimized. Material cost, shipping cost, required storage space, and maneuverability are improved. Additionally, the front suspension system and vehicle frame structure enable the accelerator and brake pedals to be positioned to provide longer legroom for both driver and passenger. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The structure, operation, and advantages of the present invention will become further apparent upon consideration of the following description, taken in conjunction with the accompanying drawings in which: 
       FIG. 1  is a left side front perspective view of an embodiment of a go-cart; 
       FIG. 2  is a left side rear perspective view of the go-cart embodiment shown in  FIG. 1 ; 
       FIG. 3  is a left side view of view of the go-cart embodiment shown in  FIG. 1 ; 
       FIG. 4  is a front view of the go-cart embodiment shown in  FIG. 1 ; 
       FIG. 5  is a top view of the go-cart embodiment shown in  FIG. 1 ; 
       FIG. 6  is an enlarged, fragmentary front elevational view of the left front wheel suspension system of the go-cart embodiment shown in  FIG. 1 ; 
       FIG. 7  is an enlarged, fragmentary top elevational view of the left front wheel suspension system of the go-cart embodiment shown in  FIG. 1 ; 
       FIG. 8  is a fragmentary, perspective view of the driver&#39;s side front suspension system, in exploded form; and 
       FIG. 9  is a fragmentary, perspective view of the driver&#39;s side front suspension system, in assembled form. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now to the drawings, and particularly to  FIGS. 1 through 5  thereof, there is shown a vehicle  10  in the form of a two-person go-cart. The vehicle is a four-wheeled, rear drive, gasoline-engine-powered vehicle having an open, tubular frame body structure. The body structure is formed from a number of interconnected frame sections that are defined by tubular steel members. 
   The body structure includes a base frame  12 , to which a floor pan  14  is attached, such as by welding, or the like, and which supports a pair of side-by-side seats, a driver&#39;s seat  16  and a passenger&#39;s seat  18 , each having a seat section and a backrest section. Base frame  12  includes a generally rectangular rear base frame section  20 , on which seats  16  and  18  are mounted for fore and aft movement, and a trapezoidal front base frame section  22  that extends forwardly of rear base frame section  20 . The shorter base  24  of front base frame section  22  is at the front end of vehicle  10 . Floor pan  14  is secured to and carried by the front base frame section  22 , such as by welding, or the like, and the forward end of front base frame section  22  includes a bumper structure  26  in the form of a pair of parallel, forwardly and upwardly extending bumper support bars  28  that extend from shorter base  24  of front base frame section  22  and terminate in a laterally extending bumper member  30 . 
   Extending in a rearward and upwardly angled direction from bumper member  30  is a trapezoidally-shaped front support frame  32 . As best seen in  FIGS. 3 and 5 , a steering column  34  that extends from a steering wheel  36  to one end of a steering control link  38  is suitably supported from cross member  40  of front support frame  32 . The other end of steering control link  38  is operatively connected with a rack and pinion steering mechanism  42  that is rigidly secured to bumper support bars  28 . Each end of steering control link  38  includes a universal joint to allow steering column  34  to be laterally offset from the center of steering mechanism  42 , and from the vehicle longitudinal centerline  44 , as seen in  FIGS. 3 and 5 . 
   As best seen in  FIGS. 1 and 3 , each side of vehicle  10  includes a generally loop-shaped side frame  46  that extends from the front toward the rear of the vehicle. Side frames  46  each extend in a rearward and upwardly sloping direction from front support frame  32  to a substantially horizontal intermediate section  48 , then to a rearwardly and downwardly sloping rear section  50 , to a reverse bend  52  and down to rear crossbar  54  of base frame  12 . Side frames  46  are substantially parallel to vehicle longitudinal centerline  44  and to each other, as seen in  FIG. 5 , and they define respective vehicle side planes that lie between the vehicle centerline and the center planes of each of respective rear wheels  56 . Between each of side frames  46  is a forward upper crossbar  58  and a rear upper crossbar  60  to define an open roof and to provide rigidity to the upper section of the vehicle framework for rollover protection. An upwardly and rearwardly sloping support bar  62  extends from substantially the center of a base frame rear crossbar  64  to rear upper crossbar  60 . 
   Positioned between the planes defined by side frames  46  is an engine support frame  66  that carries an engine/transaxle drive assembly  68  from which respective drive axles (not shown) extend laterally outwardly and are operatively coupled with rear wheels  56  for propelling vehicle  10  over the ground. A forward crossbar  70  of engine support frame  66  is pivotally coupled with base frame  12  rear crossbar  64 . A pneumatic or hydraulic shock absorber  72  with a surrounding coaxial coil spring  74  extends between a rear crossbar  76  interconnecting side frames  46  and a bracket (not shown) carried on the axle housings of each of rear wheels  56  for resiliently supporting the engine/transaxle assembly  68  and rear drive wheels  56  in cantilever fashion relative to the frame of vehicle  10 . 
   Each of front wheels  78  is independently suspended from and carried by the vehicle frame. Referring to  FIGS. 6 through 9 , which although showing only the left front wheel area, also apply to the right front wheel area in that similar elements are provided in the same relative relationship. An upwardly-extending, inwardly-inclined suspension forward support bar  80  extends from front base frame member  22  to front support frame  32  on each side of vehicle longitudinal centerline  44  a short distance behind bumper member  30 . A suspension inner support bracket  82  is rigidly affixed to each of to suspension forward support bars  80 . A suspension outer support bracket  84  is carried by a front wheel axle member  86  that rotatably carries front wheel  78 . Extending between and pivotally connected with each of suspension inner support bracket  82  and suspension outer support bracket  86  are a pair of substantially parallel upper and lower front control arms  88 ,  90 , respectively, that are oriented substantially perpendicularly relative to vehicle longitudinal centerline  44  and are inclined inwardly and upwardly from the respective front wheels  78  to the vehicle frame when the vehicle is in an unloaded condition, as shown in  FIG. 6 . 
   Also pivotally extending from respective upper and lower connection points of suspension outer support bracket  84  is a pair of substantially parallel, inwardly and rearwardly extending upper and lower rear control arms  92 ,  94 , respectively. As best seen in  FIG. 2 , a support bar  96 , that extends between and is rigidly affixed at its respective ends to each of base frame  12  and front support frame  32 , carries a suspension rear inner support bracket  98  that pivotally receives inner ends of each of upper and lower rear control arms  92 ,  94 . Furthermore, as is apparent from  FIGS. 5 ,  7 , and  8 , upper and lower rear control arms  92 ,  94 , respectively, are each J-shaped, with the bend of the J facing inwardly toward vehicle longitudinal centerline  44 , to minimize interference with the distance to which each of front wheels  78  of the vehicle can be turned about a vertical axis in a steering maneuver, and thereby reduce the minimum turning circle radius of the vehicle for improved maneuverability. 
   A pneumatic or hydraulic front shock absorber  100  and a surrounding coaxial coil spring  102  is connected between front support frame  32  and a crossbar  104  extending between and interconnecting lower front control arm  90  and lower rear control arm  94 , as best seen in  FIGS. 6 and 7 . Because of the relatively long lengths of the respective front suspension control arms, a significant amount of vertical wheel travel can be accommodated, thereby providing more comfortable riding and improved vehicle stability when driving the vehicle over uneven terrain. 
     FIGS. 8 and 9  are fragmentary perspective views of the driver&#39;s side front suspension structure. Although not shown, it should be understood that the passenger&#39;s side front suspension structure is the mirror image of the driver&#39;s side structure.  FIG. 8  shows the structure in exploded form and  FIG. 9  shows the structure in its assembled form. As shown, the lower end  126  of shock absorber  100  is connected with a clevis  128  that can be welded to crossbar  104  and that allows pivotal movement of the lower end of shock absorber  100  relative to crossbar  104 . The innermost ends  130 ,  132  of front control arms  88 ,  90 , respectively, and the innermost ends  134 ,  136  of rear control arms  90 ,  92 , respectively, are each connected with the cart frame by means of respective eyebolts  138  that are pivotally connected with forward inner support bracket  82  and rear inner support bracket  98 , respectively. 
   The outer ends of each of the upper and lower control arms are connected with outer support bracket  84  through respective ball joints  140 . Outer support bracket  84  also rigidly carries an axle  142  that rotatably supports a front wheel. Also rotatably carried by axle  142  are a brake rotor disc  144 , a wheel hub  146 , and related bearing and seal elements  148 . 
   Although not shown in the drawings, it should be understood that a tie rod extends from each of the rack and pinion steering gear mechanism ends  106  to the respective suspension outer support bracket  84  at a front wheel  78 . As is apparent from  FIG. 7 , the steering connection point  108  at front wheel  78  is offset in a forward direction relative to the vehicle longitudinal axis, from the vertical pivot axis of front wheel  78  and from a transverse vertical plane in which the upper and lower front control arms lie. Further, it should be understood that each of the tie rod ends includes a ball joint connection at the ends of steering gear mechanism  106  and at connection point  108  of outer support bracket  84 . 
   The positions relative to the overall vehicle structure of the foot pedals for operating the vehicle are best seen in  FIGS. 5 and 7 . An accelerator pedal  110  is provided to the left of and adjacent to vehicle longitudinal centerline  44  and is pivotally supported relative to floor pan  14 . Pedal  110  is carried on an accelerator pedal arm  112  that is secured to a sleeve  114  that is rotatably carried on a pivot pin (not shown) that is supported from floor pan  14  in such a way as to allow sleeve  114  to pivot about its own axis. Accelerator pedal  110  is operatively connected with engine/transaxle assembly  68  by a suitable connection means (not shown), such as a cable, or the like, to control the engine speed, and thereby the vehicle speed. 
   Similarly, a brake pedal  116  is provided to the left of accelerator pedal  110 , adjacent to base frame  12 , and is also pivotally supported relative to floor pan  14 . Pedal  116  is carried on a brake pedal arm  118  that pivots about the axis of sleeve  120  that is rotatably carried on a pivot pin (not shown) that is supported from floor pan  14  in such a way as to allow sleeve  120  to pivot about its own axis. Brake pedal  116  is operatively connected with a suitable vehicle braking system, such as by a mechanical or hydraulic mechanism connected with brake pads carried at the vehicle wheels. 
   The operator foot contact surfaces of each of pedals  110 ,  116  can be of the order of about 8½ inches from the axis of rotation of front wheels  78  when the front wheels are in the straight-ahead position. The pivot axes of each of pedal arms  112 ,  118  can be of the order of about 9¾ inches from the axis of rotation of front wheels  78  when the front wheels are in the straight-ahead position. Such a positioning of the pedal surfaces and the pedal arm pivot axes relative to the rotation axes of the front wheels enables a more compact vehicle structure to be utilized, to facilitate efficient and economical shipping of the vehicles in standard cargo containers, and it also serves to provide sufficient leg room for vehicle operators of different sizes. In that regard, the overall length of a vehicle of the type described herein can be of the order of about 84 inches, to enable efficient placement in cargo containers having an interior length of 87½ inches and an interior width of 50 inches. For a vehicle having an overall length of 84 inches, the front-to-rear wheelbase length can be about 67¼ inches. 
   As shown in  FIGS. 3 ,  5 ,  6 , and  7 , a lower side member  122  extends along each of the driver&#39;s and passenger&#39;s sides of the vehicle at a height between base frame  12  and forward and rear upper crossbars  58 ,  60  that define a roof frame. Side members  122  are attached at their forward ends to respective suspension forward support bars  80  that extend between the forward portion of front support frame  32  and base frame  12 . At their rearmost ends each of side members  122  is attached to the side frame structure at a respective roof support member  124 . As can be seen in  FIG. 5 , side members  122  diverge outwardly and rearwardly from the respective suspension forward support bars  80  to a point laterally adjacent the front edges of the respective seats  16 ,  18 , then extend rearwardly substantially parallel to each other to a point laterally adjacent the respective seat back cushions. They then curve inwardly to their connection with the respective roof support member  124 . 
   Although particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit of the present invention. It is therefore intended to encompass within the appended claims all such changes and modifications that fall within the present invention.