| 摘要 |
PROBLEM TO BE SOLVED: To solve the problems that the center of a conventional carriage can not be pushed or pulled with a good footing, grounding pressure of wheels of a conventional four-wheeled carriage concentrate on diagonal wheels because of unevenness in a field, so that other diagonal wheels are less loaded, power driving can not be achieved with simple structure, and it is difficult for a powerless person to easily make direction change on a work load at ends of ridges, on a farm road, and in the field.SOLUTION: Three ridge grooves are moved and then the ridge grooves serving as a work road are always present under the center of a carriage, so that the center of the carriage can be pushed and pulled with a good footing. A linear shape connecting grounding points of wheels is a triangle or diamond shape comprising a combination of triangles, and then while a triangular shape carriage has thee wheels equally weighted, a diamond shape carriage has a wheel of a center groove weighted by the majority. The diamond shape carriage avoids having right and left wheels grounded strongly by being slightly floated, and the triangular shape carriage has a front wheel floated. The diamond shape carriage is easily turned by providing a steering wheel and only one wheel rolling in the center ridge serves as a driving wheel. |
