Motorcycles exhibit handling characteristics which are superior in many ways over automobiles, and have less aerodynamic drag and reduced rolling resistance as compared with standard automobiles and automobile tires. Reduced aerodynamic and rolling resistance can result in improved fuel economy and vehicle performance. The preferred embodiment of the invention has four (4) tires and is therefore capable of carrying a higher gross weight than a typical motorcycle with two (2) tires. The vehicle can accommodate a larger and heavier engine, heavier fuels and loads such as batteries, more cargo, and the weight of an enclosed aerodynamic body to protect the occupants from the elements and from crashes, while reducing aerodynamic drag.
A vehicle designed around this suspension system can be constructed as narrow as a motorcycle, which is important because frontal area and shape are significant determinates of aerodynamic drag. The combination of minimal frontal area, an enclosed aerodynamic passenger/cargo compartment, and low rolling friction (drag) motorcycle tires yields improved fuel economy.
No computers, sensors, or mechanical systems are necessary to lean the vehicle or to keep it upright at speed. The only lean control mechanism required is a simple combination of bracing which will lock the vehicle in an upright position at speeds below which the gyroscopic effect of the turning wheels is insufficient to provide control-less than approximately three (3) to five (5) miles per hour.
The vehicle's suspension system can be softer and provide a smoother ride than motorcycles and many non-tilting vehicles such as autos, trucks, and ATVs. Typical motorcycle suspension systems are thirty percent (30%) to fifty percent (50%) stiffer than those of non-tilting vehicles, because motorcycles experience all of the lateral acceleration or “G” force loading occurring during turning maneuvers. The proposed suspension system experiences none of the lateral acceleration of a motorcycle, because the suspension system does not lean while turning. It remains in and acts only in the vertical like the suspension system of a typical non-leaning vehicle. Suspension systems of non-tilting vehicles must resist the forces causing the vehicle to lean to the outside of a turn and the resulting outward weight transfer. The proposed suspension system experiences no lateral weight transfer while turning because the vehicle's mass is moved to the inside of the turn, as is a motorcycle's during a balanced turn.
Compared with a typical motorcycle, this vehicle will have twice the traction—promoting shorter braking distances, improved cornering, and the ability to accommodate more powerful engines. Due to the relatively smaller contact patch of motorcycles, the vehicle is less susceptible to hydroplaning than automobiles and trucks. Having the same overall width of a motorcycle makes a vehicle easier to maneuver, requires less parking space, and it can use car pool lanes.
With two (2) front wheels, this design has inherently better front wheel traction and is more stable and safer than vehicles with one (1) tilting or fixed front wheel. As weight shifts forward as a vehicle slows and stops, front wheel traction is critical for stopping quickly, a major safety factor.
Vertical posts 1 rigidly attached to both ends of a rigid structure 2 extending the full length of a vehicle so that the vertical posts are located at or near the center of the vehicle's front and rear wheels. Opposing combination shock absorber and spring assemblies 3 are attached at the top of the posts. The lower end of the combination shock absorber and spring assembly is attached to or toward the wheel end of the lower A arms 4. The amount of force transferred by the shock absorber and spring assembly vertically and horizontally to the vertical post is determined by the lengths of the sides of the triangle comprising the shock absorber and spring assembly, the distance from the attachment point of the lower end of the shock absorber to the vertical post, and the height (length) of the vertical post. The springs incorporated within the shock absorber and spring assembly have sufficiently high spring rate and tension to maintain the vertical posts and the shock absorber and spring assembly in a vertical posture. A lengthwise structure 5 connecting the two (2) vertical posts will maintain a similar orientation as a result. The vehicle's cargo, power plant and drive train, and fuel tank are attached to the lengthwise structure connecting the two (2) vertical posts. The accompanying drawing
A second lengthwise structure 6 extending the full length of the vehicle is located above the first lengthwise structure (carrying the vehicle's power plant, drive train, fuel, and cargo) and is attached to the vertical members extending downward at both ends to the lower (first) lengthwise structure. These vertical members are attached to the lower lengthwise structure to allow the vertical members and the second (upper) lengthwise structure to rotate around the lower (first) lengthwise structure. The inner ends of the upper A arms and passenger compartment are attached to the upper (second) lengthwise structure. Regardless of the lean angle or irregularities in the road surface, the upper and lower A arms will remain parallel (with each other) and the tires will remain parallel (with each other and with the vertical members connecting the upper and lower lengthwise members).
As depicted and revealed herein, at speeds over approximately three (3) miles per hour the vehicle will require no system—either automatic or operator controlled—to keep the vehicle upright while traveling straight, or to force it to lean while turning. The vehicle will use the gyroscopic action of the rotating wheels to remain stable, upright, or lean and turn like a motorcycle or bicycle. As the driver steers and thereby applies a horizontal torque to the front wheel(s), the front wheel(s) will generate a perpendicular vertical torque. Like a standard motorcycle, a steering input turning the front wheel(s) to the left will cause the vehicle to lean and simultaneously turn to the right. The tilting mass of the vehicle will behave and affect the vehicle's handling just like the same mass on a motorcycle. The non tilting mass of the vehicle will not lean or rotate like the tilting portion, but it will be moved to the inside of the turn as the vehicle leans or tilts just like the tilting portion. If the center of gravity of the non tilting mass is at the same level or height that it is moved from side to side, other than requiring less force to initiate a turn or directional change (because this mass does not rotate), it will have the same effect on handling as the tilting mass. At speeds below approximately three (3) miles per hour, the gyroscopic effect of the rotating wheels will be insufficient to control the vehicle. Steering will be reversed, and steering toward the right will effect a right turn and the leaning portion of the vehicle will have to be locked upright or the driver will have to put his feet down.
The suspension system provides effective individual damping of each wheel in that each wheel has its own damping system/shock absorber and the actions of each wheel and forces generated by each damping system/shock absorber and spring assembly will have minimal impact upon other damping system/shock absorber(s), spring assembly(s) and wheel(s). The reasons for this effect are:
1. All of the vehicle's shock absorbers are connected to the non-leaning lengthwise rigid structure. When one shock absorber reacts to a bump, its actions will be distributed to and resisted by the other shock absorbers and suspension springs. In the example set forth in the accompanying drawings, the forces generated by each shock absorber will be distributed to and resisted by three (3) other shock absorbers and springs.
2. Most of the vehicle's mass is carried by the non-leaning portion of the vehicle. Increasing the mass of the non-leaning rigid structure connecting the vehicle's suspension systems will increase the non leaning structure's inertia, further reducing the effect one shock absorber has on the vehicle's other shock absorber(s) and wheel(s).
The vehicle will lean and therefore respond to directional changes easier and more quickly for its overall mass. The non-leaning mass is moved to the inside of a turn just like the leaning mass, but it does not lean or rotate like all the mass does on a typical motorcycle. Since the non-leaning mass does not rotate it will be easier to change the lean angle and turn the vehicle than if the entire mass of the vehicle were to rotate when initiating a turn.
REFERENCES CITEDSer. No.InventorDateGroup Art Unit/Class6,874,793ChoudheryApril 2005 280/5.5215,765,897Braun/DaimlerJune 1998280/2824,887,829PrinceApril 1987280/2824,632,413Fujita et alDecember 1986280/1124,515,390GreenbergMay 1985280/6754,478,305Martin, IIOctober 1984180/2154,375,293SolbesMarch 1983280/21 4,351,410TownsendSeptember 1982280/1123,606,374CapgrasSeptember 19713,089,710FiolaMay 19632,787,473ChiodoApril 1957 This invention relates to and claims priority based upon Provisional Patent No. 60/731,415, filed 31 Oct. 2005.