초록 ▼

A vehicle including a frame; a rider support platform supported by the frame; a pair of first wheel units pivotably supported by the frame; a pair of second wheel units supported by the frame; first and second handlebars pivotably supported by the frame; a first linkage connecting the first handleba

A vehicle including a frame; a rider support platform supported by the frame; a pair of first wheel units pivotably supported by the frame; a pair of second wheel units supported by the frame; first and second handlebars pivotably supported by the frame; a first linkage connecting the first handlebar to one of the first wheel units so that pivotable movement of the first handlebar causes wheel of the one of the first wheel units to turn relatively to the frame; a second linkage connecting the second handlebar to the other of the first wheel units so that pivotable movement of the second handlebar causes wheel of the other of the first wheel units to turn relatively to the frame; and a movement coordinator which connects the first and second linkages to each other so that pivotable movement of one or both of the first and second handlebars in one direction causes the wheels of both first wheel units to turn in the same direction.

대표청구항 ▼

What is claimed is: 1. A vehicle comprising: a structural frame; a rider support platform supported by the structural frame; a pair of first wheel units pivotably supported by the structural frame, each first wheel unit comprising a first wheel; a pair of second wheel units supported by the structu

What is claimed is: 1. A vehicle comprising: a structural frame; a rider support platform supported by the structural frame; a pair of first wheel units pivotably supported by the structural frame, each first wheel unit comprising a first wheel; a pair of second wheel units supported by the structural frame, each second wheel unit comprising a second wheel; a first handlebar pivotably supported by the structural frame so that the first handlebar is pivotable relatively to the structural frame in opposite first and second directions; a second handlebar pivotably supported by the structural frame so that the second handlebar is also pivotable relatively to the structural frame in the first and second directions; a first linkage connecting the first handlebar to one of the first wheel units so that pivotable movement of the first handlebar causes the first wheel of the one of the first wheel units to turn relatively to the structural frame; a second linkage connecting the second handlebar to the other of the first wheel units so that pivotable movement of the second handlebar causes the first wheel of the other of the first wheel units to turn relatively to the structural frame; and a movement coordinator which connects the first and second linkages to each other so that pivotable movement of one or both of the first and second handlebars in the first or second direction causes the first wheels to turn in the same directions, wherein pivotable movement of the first and the second handlebar in opposite directions causes each of the wheels in the pair of first wheel units to point in opposite directions in a toe-in configuration causing a braking action in a relatively straight line. 2. The vehicle of claim 1, wherein each of the first and second linkages comprises: a steering linkage having a first end pivotably connected to the respective handlebar, and a second end opposite to the first end; a steering pivot arm which is pivotably connected to the second end of the steering linkage at a first pivot point; a tie rod having opposite first and second ends, the steering pivot arm being pivotably connected to the first end of the tie rod at a second pivot point; and a steering arm having a first end pivotably connected to the second end of the tie rod, and a second end opposite to the first end and fixedly connected to the respective wheel unit, wherein the steering pivot arms of the first and second linkages are pivotably connected to the structural frame at a common third pivot point so that the steering pivot arms are pivotable relatively to each other about the third pivot point. 3. The vehicle of claim 2, wherein the first, second and third pivot points of each steering pivot arm form points of a triangle. 4. The vehicle of claim 2, wherein the movement coordinator comprises a spring attached to each of the steering pivot arms of the first and second linkages at a location away from the third pivot point thereof so that pivotable movement of one of the steering pivot arms in an outward direction causes the other of the steering pivot arms to follow in the same direction. 5. The vehicle of claim 2, wherein the first wheels are front wheels and the second wheels are rear wheels. 6. The vehicle of claim 5, further comprising a bumper disposed forward of the first wheels and supported by the structural frame. 7. The vehicle of claim 1, wherein pivotable movement of the first and the second handlebars in opposite directions is resisted by at least one of a spring and an elastic member such that application of an amount of pivotal force on the first and the second handlebars in opposite directions is required to overcome the resistance of the at least one of the spring and the elastic member to cause the toe-in braking action. 8. A vehicle comprising: a structural frame; a rider support platform supported by the structural frame; a pair of first wheel units pivotably supported by the structural frame, each first wheel unit comprising a first wheel; a pair of second wheel units supported by the structural frame, each second wheel unit comprising a second wheel; a first handlebar pivotably supported by the structural frame so that the first handlebar is pivotable relatively to the structural frame in opposite first and second directions; a second handlebar pivotably supported by the structural frame so that the second handlebar is also pivotable relatively to the structural frame in the first and second directions; a first linkage connecting the first handlebar to one of the first wheel units so that pivotable movement of the first handlebar causes the first wheel of the one of the first wheel units to turn relatively to the structural frame; a second linkage connecting the second handlebar to the other of the first wheel units so that pivotable movement of the second handlebar causes the first wheel of the other of the first wheel units to turn relatively to the structural frame; and a movement coordinator which connects the first and second linkages to each other so that pivotable movement of one or both of the first and second handlebars in the first or second direction causes the first wheels to turn in the same direction, wherein the structural frame comprises a first sub-structural frame pivotably supporting the first wheel units and the first and second handlebars, and a second sub-structural frame supporting the second wheel units, the rider support platform comprising a first sub-rider-support platform supported by the first sub-structural frame, and a second sub-rider-support platform supported by the second sub-structural frame, the second sub-rider-support platform being pivotably connected to the first sub-rider-support platform for folding the vehicle. 9. The vehicle of claim 8, wherein the second sub-rider-support platform is pivotably connected to the first sub-rider-support platform by a hinge. 10. The vehicle of claim 8, wherein the second sub-structural frame is releasably connected to the first sub-structural frame. 11. The vehicle of claim 10, wherein the second sub-structural frame is releasably connected to the first sub-structural frame by a connector which comprises a frame support bracket fixedly attached to one of the first and second sub-structural frames and having a through hole, a complementary through hole in the other of the first and second sub-structural frames, and a lock pin received in said holes. 12. The vehicle of claim 11, wherein the frame support bracket is fixedly attached to the first sub-structural frame and extends outward therefrom, and the complementary through hole is formed in the second sub-structural frame. 13. The vehicle of claim 11, wherein the lock pin comprises a ball-lock pin or a bolt and a nut. 14. The vehicle of claim 1, wherein each of the first and second wheel units comprises a spindle bracket pivotably supported by the structural frame and having holes of different heights, and an axle having a first end rotatably attached to the respective wheel and a second end non-rotatably placed in one of the holes of the spindle bracket. 15. The vehicle of claim 14, wherein placing the second end of said axle from the one of the holes of the spindle bracket to another of the holes of the spindle bracket changes a height of the rider support platform relative to the respective wheel. 16. The vehicle of claim 14, wherein said axle is threaded, and each of said holes is also threaded. 17. The vehicle of claim 14, wherein a handle is attached to the first end of said axle. 18. A vehicle comprising: a structural frame comprising a front sub-structural frame and a rear sub-structural frame; a rider support platform comprising a front sub-rider-support platform supported by the front sub-structural frame, and a rear sub-rider-support platform supported by the rear sub-structural frame and pivotably connected to the front sub-rider-support platform; a pair of front wheel units, each front wheel unit comprising a front wheel, a spindle bracket pivotably supported by the front sub-structural frame and having holes of different heights, and an axle having a first end rotatably attached to the front wheel and a second end non-rotatably received in one of the holes of the spindle bracket; a pair of rear wheel units supported by the rear sub-structural frame, each rear wheel unit comprising a rear wheel; a first handlebar pivotably supported by the front sub-structural frame so that the first handlebar is pivotable relatively to the front sub-structural frame in opposite first and second directions; a second handlebar pivotably supported by the front sub-structural frame so that the second handlebar is also pivotable relatively to the front sub-structural frame in the first and second directions; a first linkage connecting the first handlebar to the spindle bracket of one of the front wheel units so that pivotable movement of the first handlebar causes the front wheel of the one of the front wheel units to turn relatively to the front sub-structural frame; a second linkage connecting the second handlebar to the spindle bracket of the other of the front wheel units so that pivotable movement of the second handlebar causes the front wheel of the other of the front wheel units to turn relatively to the front sub-structural frame; and a movement coordinator which connects the first and second linkages to each other so that pivotable movement of one or both of the first and second handlebars in the first or second direction causes the front wheels to turn in the same direction.