LEANING WHEELED PERSONAL ELECTRIC VEHICLE
An electric vehicle which is able to be steered by conventional bicycle-style steering, leaning rear steering or a combination of the two is herein described.
Latest ZUUMCRAFT, INC. Patents:
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/038,362, filed Mar. 20, 2008, entitled “Lean Steering Truck With A Torsion Spring Assembly” and claims the benefit of U.S. Provisional Patent Application Ser. No. 61/038,364, filed Mar. 20, 2008, entitled “Leaning Three Wheeled Personal Electric Vehicle”, which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTIONThis invention relates to wheeled leaning vehicles used primarily for personal transportation. The preferred embodiment described below falls within the emerging class of very light electric vehicles, a sub-class of electric vehicles used primarily for human transportation.
BACKGROUND OF THE INVENTIONThis invention relates to electrically propelled leaning vehicles. Within the set of prior art the following subsets are known:
Within the subset of electrically propelled vehicles are a variety of designs such as U.S. Pat. No. 5,918,692 which typically seek to minimize weight and maximize interior volume thereby resulting in centers of mass higher than their gas powered counterparts. The limitations of this sub-set of the prior art include significantly degraded vehicle handling, decreased corner entrance and exit speeds, greater passenger discomfort, and reduced traction in inclement environmental conditions such as rain or snow.
Within the subset of leaning vehicles a significant proportion envision complicated, inefficient drive systems which seek to transfer the output of a central power unit, such as a gasoline fueled engine, to a plurality of wheels. An examples of this includes U.S. Pat. No. 4,456,277. This prior art is significantly limited by including telescoping drive shafts, chain-tensioner systems, or other methods to deliver power to wheels that have a variable distance, camber, and lean relative to the power unit.
Within the subset of three-wheeled vehicles the prior art consists of designs which often have a leading or trailing single wheel opposite a pair of wheels. This subset is severely limited by the manner in which the two co-axial wheels are connected. Most limited are those which feature a solid axle interconnecting the two co-axial wheels, such as U.S. Pat. No. 3,776,353. These suffer from extremely poor cornering and handling. The prior art also includes a set of designs which interconnect the pair of co-axial wheels using mechanical or electro-mechanical linkages, such as U.S. Pat. No. 4,087,106. This sub-set typically lacks provision to return the vehicle, and thereby the rider, to a neutral position subsequent to cornering, turning, or other handling maneuvers.
The herein described invention overcomes the significant limitations of the prior art:
SUMMARY OF THE INVENTIONBy combining one or a plurality of in-hub electrically powered motors with the novel leaning mechanism described herein, a vehicle capable of leaning into curves and handling in direct response to rider weight shifts is achieved. In one embodiment the powered wheel is located in front of the standing rider, with two turning, canting wheels placed behind the rider. The rider is able to use handlebar controlled steering during slow-speed maneuvering and is able to tilt the riding platform, by shifting pressure to one foot or the other, to add in a variable and instantaneous amount of rear-steering. In another embodiment one to four in-hub electrical motors are employed, up to one on each of four wheels, two afore and two behind the seated or standing rider. The novel leaning mechanism described is placed both afore and behind the rider and each interconnects the two associated, powered wheels. In this embodiment an all wheel drive, lean steering, electric vehicle is established.
In one aspect a lean steering vehicle includes a main platform and a front wheel assembly coupled to a forward end of the main platform. A torsion hanger assembly is coupled to the main platform, is rotatable around a first axis, and provides resistive force against rotation around the first axis from a neutral position. A first swing arm is rotatably coupled to the torsion hangar assembly. A first rear wheel is rotatably coupled to the first swing arm at a point distal to the point at which the first swing arm is coupled to the torsion hangar assembly. An electric motor is coupled to at least one of the front wheel assembly and the rear wheel to provide a driving force. Additionally a second rear wheel can be included and coupled to the vehicle in the same manner as the first rear wheel.
The following detailed description is directed to certain specific embodiments of the invention. However, the invention can be embodied in a multitude of different systems and methods. In this description, reference is made to the drawings wherein like parts are designated with like numerals throughout.
As shown in
In this presently described embodiment the rear wheel assembly 120 is comprised of a pair of swing arms 121 which span the distance between the torsion hanger assembly 122 and the rear wheels 123. Each rear wheel 123 is mounted to a swing arm 121 so as to provide free rotation, in this embodiment through the use of sealed bearings. The swing arms 121 also directly support brake calipers 124 which transfer force onto rear brake rotors 125, which are concentrically mounted to the freely rotating rear wheels 123, in order to stop the rotation of the said rear wheels 123.
As shown in
As shown in
As shown in
In one embodiment the torsion spring 230 and spring chamber 430 form an interchangeable sub-assembly which, when changed to a torsion spring 230 of varying spring constants so vary the ride dynamics of the vehicle. In another embodiment the torsion spring 230 is of a progressively varying spring constant; for every degree the torsion spring 230 is compressed an incrementally varying force is exerted upon the assembly 120 thereby providing varying ride dynamics in relation to the lean angel of the main platform 107.
As shown in
-
- Lean to Turn Ratio∝{Rider Weight, Vehicle Weight, Torsion Spring Constant, Swing Arm Lengths, Front Wheel Offset, Front Wheel Trail, Wheel Base, Front and Rear Wheel Radii}
And the Restorative force exerted upon the vehicle and rider is governed by Proportionality 2:
-
- Restorative Force∝{Normal Force, Length of Swing Arms, Wheel Radii, Inflated Tire Spring Constant, Torsion Spring Constant, Combined Rider and Vehicle Weight, and Wheel Base}
As shown in
In an alternative embodiment the controller 602 includes a secondary all wheel drive controller 610 to regulate power distribution and monitor power distribution to each of Left Front Motor 611, Right Front Motor 612, Left Rear Motor 613, Right Rear Motor 614. In this manner an all wheel drive configuration is achieved together with a sensing system to monitor and counteract wheel slippage and respond directly to varying wheel speeds, as in cornering.
As shown in
The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent exemplary embodiments of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments and that the scope of the present invention is accordingly limited by nothing other than the appended claims.
Claims
1. A lean steering vehicle comprising:
- a main platform;
- a front wheel assembly coupled to a forward end of the main platform;
- a torsion hanger assembly coupled to the main platform, rotatable around a first axis, and providing resistive force against rotation around the first axis from a neutral position;
- a first swing arm rotatably coupled to the torsion hangar assembly;
- a first rear wheel rotatably coupled to the first swing arm at a point distal to the point at which the first swing arm is coupled to the torsion hangar assembly; and
- an electric motor coupled to at least one of the front wheel assembly and the rear wheel to providing a driving force.
2. The vehicle of claim 1 further comprising a first control arm coupled at a first end to the first swing arm at a location on the first swing arm distal to point at which the first swing arm is coupled to the torsion hangar assembly and coupled at a second end to a part of the vehicle that is fixed in relationship to the main platform.
3. The vehicle of claim 2 further comprising a handle bar coupled to a steering column with the steering column being coupled to the front wheel assembly.
4. The vehicle of claim 2 further comprising a second swing arm rotatably coupled to the torsion hangar assembly; a second rear wheel rotatably coupled to the second swing arm at a point distal to the point at which the second swing arm is coupled to the torsion hangar assembly; and a second control arm coupled at a first end to the second swing arm at a location on the second swing arm distal to point at which the second swing arm is coupled to the torsion hangar assembly and coupled at a second end to a part of the vehicle that is fixed in relationship to the main platform.
5. The vehicle of claim 1 wherein the torsion hangar assembly includes a torsion spring.
Type: Application
Filed: Mar 19, 2009
Publication Date: Nov 3, 2011
Applicant: ZUUMCRAFT, INC. (San Diego, CA)
Inventors: Tom Boyd (San Diego, CA), Rasyad Chung (Berkeley, CA), Greg Grosset (Boulevard, CA), William Lofft (San Diego, CA), Amish Parashar (Campbell, CA)
Application Number: 12/407,558
International Classification: B60K 1/00 (20060101);