HK1188763A - Side-by-side atv - Google Patents

Description

Side-by-side all terrain vehicle

The application is a divisional application of patent applications with the application date of 19.12.2006, national application number 200680055961.6 (international application number PCT/US2006/048306) and the invention name of 'side-by-side all terrain vehicle' of the applicant, North Star industries, Ltd.

Technical Field

The present invention relates to a side-by-side all terrain vehicle having at least a pair of laterally spaced apart seating surfaces. More particularly, the present invention relates to a road compliant side-by-side all terrain vehicle.

Background

Generally, all terrain vehicles ("ATVs") and utility vehicles ("UV") are used to carry one or two passengers and a small amount of cargo across a variety of terrain. Due to the increased recreational interest in atvs, specialty atvs, such as those used for off-road, racing, and freight applications, have entered the market place. Most atvs include seats for up to two passengers, either seated side-by-side or with the passengers seated behind the driver of the atv. Side-by-side atvs having a driver and a passenger seated side-by-side in laterally spaced apart seats have become popular because of their ability to allow the passenger to share the driver's view and riding experience, rather than sitting behind the driver. Due to this side-by-side seating arrangement, most side-by-side atvs have a width of at least 54 inches (137 centimeters). An increasing number of ATV riders enjoy recreational trail riding on public lands including national parks and national forests. Most roads on such public land have imposed maximum width requirements to limit environmental damage. For example, most parks have established a maximum road width of about 50 inches, which makes the use of most side-by-side atvs on roadways unacceptable or impractical.

Disclosure of Invention

In accordance with an illustrative embodiment of the present disclosure, an all-terrain vehicle is shown that includes a frame, an engine supported by the frame, and a transmission supported by the frame. A pair of front wheels and a pair of rear wheels are operatively coupled to the frame. A pair of laterally spaced apart seating surfaces are supported by the frame. A pair of outermost lateral points of the vehicle define a vehicle width of less than 54 inches.

According to another illustrative embodiment of the present disclosure, an all-terrain vehicle is shown that includes a frame, an engine supported by the frame, and a transmission supported by the frame. A pair of front wheels and a pair of rear wheels are operatively coupled to the frame. A pair of laterally spaced apart seating surfaces are supported by the frame. A pair of outermost lateral points of the vehicle define a road-compliant vehicle width.

According to another illustrative embodiment of the present disclosure, an all-terrain vehicle includes a frame and a pair of laterally spaced-apart seating surfaces supported by the frame. The all-terrain vehicle also includes a pair of front wheels and a pair of rear wheels spaced apart from the pair of front wheels by a wheelbase distance. The pair of front wheels and the pair of rear wheels are adapted to support the frame above a road surface. The laterally spaced seating surfaces are supported at a seat height distance above the road surface. The all-terrain vehicle defines a ratio of a wheelbase distance to a seat height distance of at least 6.0 to 1.

The above-mentioned and other features of this invention and the manner of attaining them will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings.

Drawings

FIG. 1 is a perspective view of one embodiment of a side-by-side ATV;

FIG. 2 is an outline view of the side-by-side ATV shown in FIG. 1;

FIG. 3 is a front view of the ATV shown in FIGS. 1 and 2;

FIG. 4 is a top plan view of the side-by-side ATV shown in FIGS. 1-3;

FIG. 5 is a partial perspective view of the cab area of the side-by-side ATV shown in FIGS. 1-4;

FIG. 6 is a partial profile view of the cab area shown in FIG. 5;

FIG. 7 is a partial perspective view of one embodiment of a guard bar that may be used on a side-by-side ATV, such as the side-by-side ATV shown in FIG. 1;

FIG. 8 is another embodiment of a guard rail that may be used on a side-by-side ATV, such as the side-by-side ATV shown in FIG. 1;

FIG. 9 is a bottom plan view of the side-by-side ATV shown in FIGS. 1-4;

FIG. 10 is a partially exploded perspective view of the forward end of the ATV shown in FIGS. 1-4;

FIG. 11 is a partially exploded, perspective view similar to FIG. 10, showing details of the hood installation;

FIG. 12 is a cross-sectional view showing the hood installation with the hood partially removed from the front panel;

FIG. 13 is a cross-sectional view similar to FIG. 12 with the hood coupled to the front panel;

FIG. 14 is a rear perspective view of the frame and modular engine assembly of the side-by-side ATV shown in FIGS. 1-4;

FIG. 15 is a partially exploded rear perspective view of the frame and modular engine assembly shown in FIG. 14;

FIG. 16 is an exploded perspective view of one embodiment of an engine mount assembly that may be used on an ATV, such as the side-by-side ATV shown in FIGS. 1-4;

FIG. 17 is an exploded perspective view of another embodiment of an engine mount assembly that may be used on an ATV, such as the side-by-side ATV shown in FIGS. 1-4;

FIG. 18 is an exploded perspective view of yet another embodiment of an engine mount assembly that may be used on an ATV, such as the side-by-side ATV shown in FIGS. 1-4;

FIG. 19 is a partial front perspective view of a bottom side of the drivetrain components of the side-by-side ATV shown in FIGS. 1-4;

FIG. 20 is a partially exploded rear view of the frame and rear suspension system components of the side-by-side ATV shown in FIGS. 1-4;

FIG. 21 is a rear elevational view of the frame and suspension system illustrated in FIG. 20;

FIG. 22 is a partial rear perspective view of a steering mechanism and front axle assembly that may be used on ATVs such as the side-by-side ATV shown in FIGS. 1-4;

FIG. 23 is a partial front perspective view of the steering mechanism and front axle assembly of the ATV shown in FIG. 22;

FIG. 24 is a partial perspective view of one embodiment of a brake assembly that may be used on an ATV, such as the side-by-side ATV shown in FIGS. 1-4;

FIG. 25 is a front rear perspective view of the engine and clutch cooling components of the side-by-side ATV shown in FIGS. 1-4;

FIG. 26 is a partial rear view of the engine and clutch cooling components shown in FIG. 25;

FIG. 27 is a partial perspective view of the driver side footwell area of the side-by-side ATV shown in FIGS. 1-4;

FIG. 28 is a partially exploded view of a steering assembly that may be used on an ATV such as the side-by-side ATV shown in FIGS. 1-4;

FIG. 29 is a side elevational view of the steering assembly of FIG. 28, showing the steering wheel in a plurality of tilted positions; and

fig. 30 is a partial perspective view of an adjustable grab bar that may be used on atvs, such as the side-by-side atvs shown in fig. 1-4.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention.

Detailed Description

The embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may utilize their teachings. For example, although the following description is directed primarily to ATVs, certain features described herein may be used in other applications, such as utility vehicles, snowmobiles, motorcycles, mopeds, and the like.

Referring initially to FIG. 1, one illustrative embodiment of a side-by-side ATV 10 is shown. ATV 10 includes a front end 12, a rear end 14, and a frame 15, frame 15 being supported above the ground by a pair of front tires 22a and front wheels 24a and a pair of rear tires 22b and rear wheels 24 b. Atv 10 includes a pair of laterally spaced apart upper seating surfaces 18a, 18b and a pair of laterally spaced apart lower seating surfaces 20a, 20b, respectively. The upper seating surfaces 18a, 18b are configured to support the back of a seated operator, while the lower seating surfaces 20a, 20b are configured to support the buttocks of a seated operator. In the illustrative embodiment, the upper and lower seating surfaces 18a, 18b, 20a, 20b form a bucket seating arrangement, however a bench-type seat or any other type of seating structure may be used. Upper and lower seating surfaces 18, 20 are positioned within cab 17 of atv 10.

Protective cage 16 extends over cab 17 to help prevent the occupants of ATV 10 from being injured by passing branches or twigs, and may also serve as a support in the event of a vehicle rollover. As shown in fig. 1-4, the protective covering 16 narrows as it extends upward to allow the driver and passengers to more easily enter and exit the cab 17. Additionally, in some embodiments, a cover including one or more of a roof, windshield, and doors (not shown) may be attached to protective enclosure 16 to block weather elements, such as wind, rain, or snow. The cab 17 also includes a front console 31, an adjustable steering wheel 28 and a shift lever 29. The front console 31 may include a tachometer, odometer, or any other suitable instrument. Front end 12 of ATV 10 includes front panel 67, hood 32, and front suspension assembly 26. Front suspension assembly 26 pivotally couples front wheels 24 to ATV 10. Rear end 14 of atv 10 includes an engine cover 19, with engine cover 19 extending over a modular engine assembly 34 as shown in fig. 2, 14 and 15. Modular engine assembly 34 is illustratively disposed entirely behind upper and lower seating surfaces 18a, 18b, 20a, 20 b.

As shown in fig. 2, the front wheels 24 are supported for rotation by a front axle 36. Similarly, the rear wheels 24b are supported for rotation by the rear axle 38. In the illustrative embodiment shown in fig. 2, the wheelbase a extending between the center of the front axle 36 and the center of the rear axle 38 is equal to about 77 inches (195.6 centimeters). Seat height B is equal to the distance between low point 21 of lower seating surface 20 and the bottom of frame 15 when atv 10 is at rest. In the illustrative embodiment, the seat height B is equal to about 11.75 inches (29.8 centimeters). In the illustrative embodiment, the ratio of wheelbase to seat height, or distance a to distance B, is about 6.55 to 1. In other embodiments not shown, the ratio of the wheel base to the seat height may be equal to other suitable ratios, however the present invention contemplates ATVs having a wheel base to seat height ratio greater than about 6.0 to 1. A wheel base to seat height ratio greater than about 6.0 to 1 facilitates a relatively low center of gravity for the vehicle and further provides improved efficiency factors, handling performance, and space utilization.

Referring now to fig. 3 and 4, a front view and a top plan view of atv 10 are shown. In the illustrative embodiment, width C, which is defined as the overall width of ATV 10, extends between the outermost lateral points of ATV 10. In the illustrative embodiment, the outer surfaces of tires 22 on the front and rear ends of ATV 10 define the outermost points. In other embodiments, the width C may be measured from the outer fender of the front panel 67. It will be appreciated that both of the outer surface of the tire 22 and the fender of the front panel 67 may define the width C if the dimensions defined by each are substantially equal. In the illustrative embodiment, the width C is about 50 inches. In other embodiments, ATV 10 may be constructed of other suitable widths, however the present invention contemplates ATVs having a road-following width or a width of less than about 54 inches.

Referring now to FIG. 5, a partial view of cab 17 of ATV 10 is shown. Lower seating surface 20 is coupled to base 41 of ATV 10. Foot well area 40 extends below base 41 and encloses the foot and lower leg portions of each passenger. Foot well area 40 includes a floorboard 42 and side panels 46 on each side of ATV 10. The floor 42 includes an aperture 44 positioned to allow fluid to flow out of the floor 42. Side panels 46 extend upward from floorboard 42 on each side of ATV 10. In the illustrated embodiment, the side panel 46 extends upwardly from the floor 42 approximately 4 inches (10.2 centimeters), however the side panel 46 may be constructed of any suitable height. Side panels 46 and foot well areas 40 prevent the feet and lower leg portions of the driver and passenger of ATV 10 from moving out of cab 17 when ATV 10 is in motion, such as when traversing rough terrain. In other embodiments (not shown), side panels 46 may be removed to allow easier entry and exit into cab 17 of ATV 10.

Referring now to FIG. 7, an illustrative embodiment of side-by-side ATV 48 is shown. Atv 48 includes driver's side seat 49, side panel 52, and engine cover 54. Tube 56 extends upwardly from engine cover 54 to form boot 16. Seat guard 50 is coupled between engine cover 54 and side panel 52 to prevent a passenger seated on seat 49 from sliding laterally out of seat 49 during heavy driving. In addition, the seat guard 50 may provide protection from passing external obstacles. Seat guard 50 may also be included on the passenger side of atv 48.

Referring now to FIG. 8, another illustrative embodiment of ATV 48 is shown including additional safety bar 58. In this embodiment, safety bar 58 is coupled between tube 56 and seat guard 50 to further enclose a passenger in the cab area of ATV 48. Additionally, safety bar 58 may function as a handle when entering or exiting ATV 48. Additionally, a panel or restraining member, such as a mesh member, may also be disposed between one or more of seat guard 50, safety bar 58, tube 56, and side panel 52 to further restrain the driver or passenger's accessories from exiting the vehicle during strenuous travel.

Referring now to fig. 9, an illustrative bottom plan view of atv 10 is shown. For simplicity, the floor and bottom side shields have been removed. In this embodiment, driver side 65 of ATV 10 is shown in the upper portion of FIG. 9, while passenger side 63 is shown in the lower portion of FIG. 9. Longitudinal axis 66 separates driver side 65 from passenger side 63 and defines a longitudinal centerline of ATV 10. In this embodiment, various relatively heavy components are positioned vertically adjacent to frame 15 to lower the center of gravity of the vehicle, thereby improving balance and stability. For example, fuel tank 62 is positioned below lower seating surface 20b on passenger side 63 of ATV 10. Fuel tank 62 is supported by frame 15. As shown, the fuel tank 62 is L-shaped, however any suitable shape of fuel tank may be used. Positioning fuel tank 62 on passenger's side 63 improves the balance of ATV 10 when only the driver is on driver's side 65 of ATV 10. Battery 64 is positioned under lower seating surface 20a on driver's side 65 of atv 10. In this embodiment, battery 64 is positioned near axis 66 on ATV 10 and is relatively low, thereby improving balance. Positioning the battery 64 near the seating surface 20a also allows for easier maintenance and can shorten the plumbing to the engine assembly 34.

Referring now to fig. 10-13, front end 12 of atv 10 is shown in more detail. The front end 12 includes a hood 32, and the hood 32 may be removably coupled to the front panel 67. As shown, the hood mounting assembly includes a pair of plungers or pegs 95 removably received within a cylindrical collar 97. Plunger 95 is secured near the rear corner of cover 32, while grommet 97 is secured to front panel 67 near the rear corner of storage area 68. In this embodiment, plunger 95 and retaining ring 97 are illustratively formed of steel and a resilient material (e.g., elastomer), respectively, although any suitable material may be used. The front portion of the cover 32 includes a plurality of flanges 99a, the flanges 99a being configured to cooperate with a lip 99b formed in the front panel 67 to define a releasable hinge.

In this illustrative embodiment, the storage area 68 and the access panel 61 are positioned below the hood 32. Storage area 68 may receive a tool box, cargo net bag, or any other suitable vehicle accessory for atv 10. The access panel 61 may include any suitable engine or vehicle service port or terminal, such as a radiator fill cap, a battery charge terminal, a filler plug, or a transmission fill plug.

Referring now to fig. 14, one illustrative embodiment of frame 15 of a side-by-side atv such as atv 10 shown in fig. 1 is shown. Frame 15 includes an inner rail 72, a front cross member 71, a middle cross member 73, and a rear cross member 77. Frame 15 also includes an outer tube 70 that defines an outermost width of frame 15. The rear assembly 92 is coupled to the upper frame rails 90 and the cross member 77 and will be described in detail below. The portion of frame 15 between middle cross member 73 and rear cross member 77 supports modular engine assembly 34 of atv 10. In this embodiment, modular engine assembly 34 may include a transmission 136, such as a continuously variable transmission, and a rear differential 132, as shown in FIG. 15, prior to installation in frame 15.

Referring to fig. 14 and 15, the inner rails 72 of the frame 15 are coupled together at the front ends by the cross members 71 and at the rear ends by the rear cross members 77. Brackets 76 couple upper frame tubes 88, upper frame rails 90, vertical tubes 74, and outer tubes 70 together on each side of ATV 10. Outer tube 70 is coupled to inner rail 72 by bracket 69. Standpipe 74 is coupled at a lower end to inner rail 72. The upper frame tube 88 is coupled to the support tube 83, and the support tube 83 is coupled to the inner rail 72 at a lower end. Upper frame rails 90 are coupled at a rear end to cross tubes 91.

As shown in fig. 15, modular engine assembly 34 may be preassembled prior to installation in frame 15. During construction of frame 15, upper brace 78 is attached to frame 15 to provide dimensional stability during the welding process. During installation of modular engine assembly 34, upper brace 78 is removed from frame 15 and modular engine assembly 34 is placed on frame 15. Upper bracket 78 is then reattached to frame 15. More specifically, as shown in FIG. 14, after modular engine assembly 34 is positioned between upper frame rails 90 in frame 15, upper brace 78 may be installed.

The upper bracket 78 includes an outer bracket 86, a rear bracket 84, a cross member 80, and a diagonal member 82. The diagonal members 82 are coupled together at one end by a bracket 84 and at an opposite end by the cross member 80. Each bracket 86 is generally U-shaped and includes an aperture 85. The U-shaped bracket 86 is adapted to overlap the upper frame tube 88. The holes 85 in the bracket 86 and the holes 87 in the upper frame tube 88 align and receive fasteners to secure the upper bracket 78 to the upper frame tube 88. Bracket 84 includes holes 81 that align with holes 89 in cross tube 91 and may be secured using any suitable fasteners.

In this embodiment, modular engine assembly 34 is mounted on frame 15 of ATV 10 using a three-position mounting system to allow modular engine assembly 34 to be placed into frame 15 and bolted or attached as a unit. An illustrative embodiment of each of the three mounting assemblies is shown in fig. 16-18. Referring now to FIG. 16, a mounting system 94 positioned on the driver side of modular engine assembly 34 and frame 15 is shown. Bracket 96 is mounted to modular engine assembly 34 prior to mounting modular engine assembly 34 in frame 15. Lower bracket 102 is coupled to rail 75 of frame 15 and receives mounting plate 100. Mounting plate 100 is coupled to bracket 102 by fasteners 104.

During installation of modular engine assembly 34 into frame 15, bracket 96 is aligned with mounting plate 100, and fasteners 98 are placed in holes in bracket 96 and in holes 101 of mounting plate 100 to secure bracket 96 and modular engine assembly 34 to frame 15. Similarly, as shown in fig. 18, mounting assembly 120 is positioned on the passenger side of modular engine assembly 34 and frame 15. Bracket 128 is coupled to frame 15. The mounting plate 126 is coupled to the bracket 128 by fasteners 130. Bracket 122 is coupled to the passenger side of modular engine assembly 34 and is positioned such that when modular engine assembly 34 is installed in frame 15, the aperture in bracket 122 is aligned with central aperture 127 of mounting plate 126. Fasteners 124 extend through apertures in bracket 122 and apertures 127 in mounting plate 126 to secure modular engine assembly 34 to frame 15.

Modular engine assembly 34 is also mounted to frame 15 by a third mounting assembly shown in fig. 14 and 17. The mounting assembly 106 includes a bracket 108, side plates 116, and a mounting plate 114. The bracket 108 is coupled to the bracket 93 of the rear assembly 92. Bracket 108 includes a vertically extending plate 110 and is coupled to bracket 93 by extending fasteners (not shown) through holes 109. Side plates 116 are coupled to a rear differential 132 of engine assembly 34. Mounting plate 114 is coupled between side plates 116 by fasteners 118. During installation of modular engine assembly 34 into frame 15, vertically extending plates 110 of brackets 108 are positioned on either side of mounting plate 114. Fasteners 112 are then placed through apertures in vertically extending plate 110 and apertures 115 of mounting plate 114 to secure modular engine assembly 34 in frame 15.

Referring now to FIG. 19, a partial, forward, bottom side perspective view of the drivetrain components of ATV 10 is shown. Modular engine assembly 34 includes an engine 133, a transmission 136, and a rear differential 132. In this embodiment, the crankshaft (not shown) of engine 133 is parallel to the fore-aft direction of ATV 10 and provides a narrower overall vehicle width and an improved center of gravity of ATV 10. In this embodiment, the engine 133 is a 760cc engine producing approximately 50 horsepower. The engine 133 produces excellent acceleration characteristics and response characteristics. Atv 10 weighs about 950 pounds (430.9 kilograms) and has a power-to-weight ratio (horsepower/pound) of about 0.053/1. Any suitable engine may be used in ATV 10, and ATV 10 may be constructed of any suitable weight, however the present invention contemplates ATVs having a power to weight ratio (horsepower/pound) of at least 0.045/1.

Rear differential 132 of modular engine assembly 34 is directly coupled to transmission 136 through housing 148 to maintain center-to-center spacing and enable easy assembly. In the illustrative embodiment, rear differential 132 is a lockable electronic rear differential, however any suitable rear differential or rear axle may be used. Output shaft 138 extends from transmission 136 toward the front of ATV 10 and rotates to power front wheels 24a of ATV 10. In this embodiment, the all-terrain vehicle has on-demand all-wheel drive with switchable back-drive, however any suitable drivetrain such as two-wheel drive or four-wheel drive may be used.

As shown in fig. 19, the output shaft 138 extends below the protective panel 134. Protective panel 134 is positioned below upper and lower seating surfaces 18a, 18b, 20a, 20b and protects passengers in atv 10 from moving parts of modular engine assembly 34 and helps to shield noise. The extended end of the output shaft 138 includes a splined portion 140 adapted to engage the inner circumference of a coupler 142. Coupler 142 is coupled to gimbal 144. Universal joint 144 connects coupler 142 to a front drive shaft 146 that powers the front wheels of atv 10. The coupler 142 is movable in the forward-rearward direction on the splined portion 140 of the output shaft 138 while remaining engaged with the splined portion 140. During rough driving, the front drive wheels 146 may move in a fore-aft direction such that the coupler 142 slides longitudinally on the splined portion 140 of the output shaft 138 while the front drive shaft 146 remains rotationally coupled with the output shaft 138.

Referring now to fig. 20 and 21, the components of the rear suspension of atv 10 are shown. Rear frame assembly 92 is formed from down tubes 105, vertical tubes 107, rear brackets 160, front brackets 162, down tubes 180, and cross tubes 182 and 184. The down tube 105 is coupled to the upper frame rail 90 and extends rearward. The down tubes 180 are coupled at one end to the rear cross member 77. The opposite ends of lower tubes 180 are coupled together by cross tubes 182. Cross tubes 182 support pins 164, and pins 164 may be used to couple to a trailer or other device for towing behind atv 10. The lower ends of down tubes 105 are coupled together by cross tube 184. Front bracket 162 and rear bracket 160 extend between down tube 180 and down tube 105. Vertical tubes 107 extend downward from upper frame rails 90 and are coupled to down tubes 105. Each down tube 105 includes a bracket 186. Similarly, each standpipe 107 includes a bracket 176.

Rear wheel 24b includes an inner hub assembly 25. The lower ends of the upper and lower control arms 172 and 170 are coupled to the inner hub assembly 25 of the rear wheel 24 b. The lower end of bumper 168 is also coupled to inner hub assembly 25. The upper ends of upper and lower control arms 172 and 170 are pivotally coupled to front and rear brackets 162 and 160 on each side of ATV 10. Upper end 178 of buffer 168 is coupled to bracket 176 on standpipe 107. Stabilizer or torsion bar 174 is coupled to inner hub assembly 25 by rods 171. More specifically, rod 171 has an upper end connected to the opposite end of torsion bar 174 and a lower end connected to lower control arm 170. Torsion bar 174 is coupled to bracket 186 on down tube 105 and provides a torsional transverse connection between lower control arms 170 of rear wheels 24 b.

Rear wheels 24b may move vertically in an independent manner along a path defined by upper control arm 172 and lower control arm 170. For example, when ATV 10 encounters rough terrain, rear wheels 24b may move up and down to maintain contact with the ground. By placing bracket 176 coupled to bumper 168 on vertical tube 107 of frame 15, the load path created when rear wheel 24b moves upward is translated through the vertically positioned frame member (vertical tube 107) of frame 15. In addition, torsion bar 174 provides interaction between the independent suspensions of rear wheels 24b through respective control arms 170. As is known in the art, during cornering, torsion bar 174 resists deflection of outer rear wheel 24b caused by centrifugal force by transmitting the deflection to inner rear wheel 24 b. These elements may improve the ride and handling characteristics of ATV 10.

Referring now to fig. 22-24, the components of the front suspension, including the right front brake assembly 199, are shown. The front frame assembly 203 includes a front tube 204 coupled to an upper cross member 205. Rear tube 207 is positioned behind front tube 204 and is coupled to diagonal braces 209 and crossmember 71 (FIG. 14). The upper bracket 211 is supported by the front tube 204 and the bracket 209, while the lower bracket 213 is supported by the lower tube 215. The lower ends of the upper and lower control arms 210 and 212 are coupled to the inner hub 25 of the wheel 24 a. The lower end of the steering arm (commonly referred to as a steering rod) 208 and bumper 217 are also coupled to the inner hub of the wheel 24 a. The upper ends of upper and lower control arms 210 and 212 are pivotally coupled to lower brackets on each side of ATV 10. The upper end of the bumper 217 is pivotally coupled to a bracket 223 extending between the rear tubes 207. The control arms 210, 212 and the bumper 217 cooperate to define independent front suspensions for the right and left front wheels 24 a. More specifically, front wheels 24a may move vertically in an independent manner along a path defined by upper and lower control arms 210 and 212.

With further reference to fig. 22 and 23, a stabilizer or torsion bar 214 is coupled to the head tube. Links or rods 219a and 219b are illustratively operatively coupled to opposite left and right ends of torsion bar 214 by left and right clamps 225a and 225b and torque bars 221a and 221b, respectively. Rod 219 is coupled to inner hub assemblies 25 of right and left front wheels 24a through upper control arm 210. In use, when a force is exerted on one of the right and left front wheels 24a during vehicle travel, the front suspension can transmit the corresponding force to the other of the right and left front wheels 24 a. For example, when an upward force is applied to left front wheel 24a due to a collision or a turn, respective upper and lower control arms 210 and 212 may move upward relative to ATV 10. This upward movement may push the corresponding rod 219a upward, which may cause the corresponding end of the left torque rod 221a to move upward. The left torque rod 221a may act as a lever, exerting a torque on the left end of the torsion bar 214.

The torsion bar 214 may include a torque transfer adjuster (not shown) that determines how much of the torque applied by the left torque bar 221a (or the right torque bar 221b) is transferred to the right torque bar 221b (or the left torque bar 221 a). The clamps 225a and 225b may be repositioned or moved along the torque rods 221a and 221b to change the suspension effect. In the present example, upward movement of the left torque rod 221a may cause upward movement of the right torque rod 221b, thereby pushing the right rod 219b and connected control arms 210 and 212 upward. The upward movement of the right control arms 210 and 212 may exert an upward force on the right front wheel 24 a. Thus, the front suspension can exert a portion of the upward force exerted on the left front wheel 24a by the running road surface on the right front wheel 24 a. While the present example refers to a force exerted by the running surface on the left front wheel 24a, the front suspension can operate in a similar manner when the running surface exerts a force on the right front wheel 24 a. An illustrative embodiment of a torsion bar is disclosed in U.S. patent application serial No. 11/340,301 filed on 26.1.2006, which is expressly incorporated herein by reference.

For simplicity, only right front brake assembly 199 is shown in fig. 22 and 23, however a similar brake assembly may be used for each wheel 24 of atv 10. The front brake assembly 199 is coupled to the inner hub 25 of the wheel 24. Front axle 206 is supported by inner hub assembly 25. As described in detail above, the upper and lower control arms 210, 212 and the steering arm 208 are coupled to the inner hub 25 of the wheel 24 a. Steering arms 208 are positioned above and rearward of front axle 206 to allow caliper bracket 201 and caliper 200 to be positioned rearward or on the back side of front axle 206. Control arm 210 is positioned above steering arm 208 to facilitate the relative positioning of steering arm 208 and also caliper bracket 201 and caliper 200. The caliper bracket 201 and the brake disc 202 are also coupled to the inner hub 25 of the wheel 24. Brake caliper 200 is coupled to the back or rearward facing end of caliper bracket 201. Placing brake caliper 200 on the rearward facing end of caliper bracket 201 prevents mud and debris from piling up on caliper 200 as tire 22 is rotated forward or counterclockwise. Placing caliper 201 on the forward facing side or end of brake disc 202 may require a wiper or housing to prevent mud and debris from tire 22 from piling up on caliper 200.

Referring now to fig. 25 and 26, a front perspective view and a rear profile view of engine cover 19 of atv 10 are shown. Modular engine assembly 34 includes an engine cooling inlet 220 and a clutch cooling inlet 218. The inlets 218 and 220 extend upwardly through the opening 216 in the engine cover 19 and direct cooling air to the clutch housing 135 and the engine 133. The clutch housing 135 protects a clutch mechanism adapted to transmit power from the engine 133 to the transmission 136. Portals 218 and 220 are positioned between driver's upper seating surface 18 and passenger's upper seating surface 18 to collect air that passes between upper seating surfaces 18a and 18b as the atv travels in a forward direction. As ATV 10 accelerates, more air passes between upper seating surfaces 18a and 18b and is collected by inlets 218 and 220.

Referring now to FIG. 27, a partial perspective view of the driver's side of cab 17 of ATV 10 is shown. As described above, the cab 17 includes the upper seating surface 18, the lower seating surface 20, the steering wheel 28, and the front console 31. In this illustrative embodiment, accelerator pedal 226 and brake pedal 224 are positioned in footwell area 40 of cab 17.

Referring now to fig. 28, an exploded view of a steering assembly that may be used on an atv such as atv 10 is shown. In this illustrative embodiment, the steering wheel 28 may be tilted by pivoting about a pivot axis 227, as shown in fig. 29. Illustratively, the steering wheel 28 is infinitely adjustable, i.e., in a continuous manner, within a predetermined angular range of motion α. In the illustrative embodiment, α is defined as about 42 degrees. In another illustrative embodiment, the steering wheel 28 is telescopically adjustable in a direction along the longitudinal axis 228.

The steering wheel 28 is coupled to a rod 234 that extends through the tilt bracket 30. The rod 234 is connected to a coupling 242 that transmits the rotation of the steering wheel 28 and the rod 234 to a universal joint 244. The universal joint 244 is coupled to an upper end of a steering shaft 246. The lower end of the steering shaft 246 is coupled to a universal joint 248, and the universal joint 248 transfers rotation of the steering shaft 246 to the front gearbox assembly 247 and the steering arm 208 (fig. 22) to turn the front wheels 24. The tilt bracket 30 is pivotally coupled to the bracket 250 by a fastener assembly 235 that defines a pivot axis 227. Fastener assembly 235 may include a conventional bolt 235a, a washer 235b, and a nut 235 c. The bracket 250 includes a lower arm 232. The lower end or mounting portion 240 of the adjustment device 230 is coupled to the arm 232 of the bracket 250. An upper end or mounting portion 238 of adjustment device 230 is coupled to tab 236 of tilt bracket 30. When the steering wheel 28 is tilted upward, the adjustment device 230 is extended and the tilt bracket 30 is rotated upward. Conversely, when the steering wheel 28 is tilted downward, the adjustment device 230 is retracted and the tilt bracket 30 is rotated downward.

In the illustrative embodiment, adjustment device 230 includes a gas spring having a cylinder 252 and a movable piston rod 254. A lever 256 is operatively coupled to the piston rod 254 and is configured to selectively block fluid flow within the cylinder 252. In operation, when the lever 256 blocks fluid flow, the lever 256 is in a stop position and locks the rod 254, and therefore the steering wheel 28, in place. Actuation of lever 256 allows fluid to flow within cylinder 252 and thus allows adjustment of rod 254 and steering wheel 28. In one illustrative embodiment, the adjustment device 230 includes a device available from StabilusA gas spring.

Referring now to fig. 30, an adjustable grab bar for a passenger seated in atv 10 is shown. Adjustable grab bar 190, also shown in fig. 22 and 23, is positioned in front fender 195 of atv 10 and extends rearward toward the passenger seated in cab 17. Adjustable grab bar 190 includes a handle portion 192, tubes 193 and 194, and a locking mechanism 196. The passenger may telescopically adjust the position of the handle portion 192. Tube 193 can extend out of tube 194 and retract back into tube 194 to allow a passenger to adjust the position of handle portion 192 during entry or exit from cab 17 of ATV 10. A locking mechanism 196 secures the tube 193 and handle portion 192 in a desired position.

While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.

Claims (20)

1. An all-terrain vehicle comprising:

a frame (15) and a pair of laterally spaced apart seats (18a, 18b) supported by the frame (15), the pair of laterally spaced apart seats (18a, 18b) including a driver seat and a passenger seat;

an engine (133) supported by the frame (15), the engine (133) disposed longitudinally rearward of the pair of laterally spaced seats;

a transmission (136) coupled to the engine;

the all-terrain vehicle is characterized in that the frame rearward of the seat includes a lower rear frame portion extending at least partially below the engine and the transmission and an upper rear frame portion extending at least partially above the engine and the transmission, and at least a portion of the upper rear frame portion is detachable to mount the engine rearward of the pair of laterally spaced-apart seats.

2. The all-terrain vehicle of claim 1, wherein the upper rear frame portion includes an upper frame exterior and an upper frame interior.

3. The all-terrain vehicle of claim 2, wherein the upper frame outer portion is a fixed portion of the frame, and the inner portion is readily removable.

4. The all-terrain vehicle of any of claims 1-3, wherein the detachable inner portion is in the form of a detachable upper bracket (78).

5. The all-terrain vehicle of claim 3 or 4, wherein the upper frame outer portion defines a plane, the upper frame inner portion defines a plane, and the outer defined plane and the inner defined plane are coplanar when assembled.

6. The all-terrain vehicle of claim 5, wherein the inner portion includes a cross member (80) attachable to the upper frame outer portion.

7. The all-terrain vehicle of claim 5 or 6, wherein the interior includes two bracket members (82, 82), the two bracket members (82, 82) intersecting such that near the seat, a first member is located to the right of a second member, and near a rearmost portion of the vehicle, the first member is located to the left of the second member.

8. The all-terrain vehicle of any of claims 1-7, wherein, near a rear portion of the upper frame, the upper frame outer portion is narrower than a portion of the upper frame proximate a middle frame portion.

9. The all-terrain vehicle of claim 8, wherein, near a rear portion of the upper frame, the upper frame interior is narrower than a portion of the upper frame proximate the intermediate frame portion.

10. The all-terrain vehicle of any of claims 1-8, wherein the upper frame interior and the upper frame exterior define three points of detachable coupling between the upper frame interior and the upper frame exterior.

11. The all-terrain vehicle of claim 10, wherein a front end of the upper frame interior defines two points (86, 86) of detachable coupling with the upper frame exterior, and a rear end of the upper frame interior defines one point (84) of detachable coupling with the upper frame exterior, the point of detachable coupling at the rear end being laterally positioned between the two points of detachable coupling at the front end.

12. The all-terrain vehicle of any of claims 1-11, wherein the upper frame defines an opening defined externally therethrough sized to receive the engine therethrough.

13. The all-terrain vehicle of claim 12, wherein the upper frame interior is received within the opening and is coupled to the upper frame exterior such that passage of the engine through the aperture is blocked.

14. The all-terrain vehicle of any of claims 1-13, further comprising an outer body panel supported by the frame (15).

15. The all-terrain vehicle of any of claims 1-14, further including an engine cover (54) supported by the upper rear frame portion.

16. A method of assembling an all-terrain vehicle, comprising the steps of:

a. providing a frame comprising a front frame portion, a middle frame portion and a rear frame portion, the rear frame portion comprising a lower rear frame portion and an upper rear frame portion, wherein at least a portion of the upper rear frame portion is detachable to provide an open upper surface of the rear frame portion;

b. providing a pair of laterally spaced seats (18a, 18b) including a passenger seat and a driver seat supported by the intermediate frame portion;

c. providing an engine (133) and mounting the engine behind the pair of laterally spaced seats and through the open upper surface of the frame such that the engine is longitudinally disposed behind the pair of laterally spaced seats and supported by the lower rear frame portion;

d. coupling a transmission (136) to the engine; and

e. reattaching the detachable portion to provide a closed frame above the engine.

17. The method of claim 16, wherein the transmission is coupled to the engine prior to installation of the engine into the frame, whereby the engine and transmission define a subassembly (34) and the engine and transmission subassembly is lowered to pass through the open upper surface of the frame and be supported by the lower rear frame portion.

18. The method of claim 16 or 17, wherein the detachable portion is mounted during manufacture of the frame such that frame components are properly aligned.

19. The method of any of claims 16-18, wherein the frame components are welded together and an upper bracket (78) is attached to the frame (15) to provide dimensional stability during welding.

20. The method of any of claims 16 to 19, further providing a bonnet, wherein the bonnet (19) is positioned above the engine and supported by the upper rear frame portion.