摘要 |
PROBLEM TO BE SOLVED: To provide a handcart capable of maintaining the direction of traveling with a small force without no risk of the handcart to suddenly travel downward to the lower part of a inclined plane while a person crosses the inclined plane with the handcart, and showing the good property of traveling in a straight line even on a rough surface. SOLUTION: This handcart is provided with a left wheel 1a and a right wheel 1b of front wheels fixed on a wheel axle 2, and casters 3a, 3b as rear wheels, to concurrently rotate in the same direction. In crossing the incline plane, a force MG to rotate the handcart is developed from a component G of the gravity of the handcart and a distance L. And then, the force MF from friction forces Fa, Fb between front wheels and a road surface and a distance B acts in the direction reverse to the direction of the force MG. Accordingly, a force required to maintain the direction of traveling can be reduced. When a wheel hits an obstacle and a movement MS to change the direction of traveling of the handcart is generated, the force MF from the friction force of the front wheel acts in the direction reverse to the moment MS. Accordingly, the handcart shows the good property of traveling in a straight line.
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