| 摘要 |
<p>The equipment has a chassis of U-section with a centre (2) and two wings (3, 4). There are four small wheels (5, 6), two mounted loose on one shaft and the other two on a shaft parallel to it. Two wheels are outside the chassis along one wing and the others along the other wing. The wheels are positioned so that the centre is slightly above the ground. One of the wings has a sleeve (8) slightly inclined to it. The sleeve is lengthened (12) at its free end by a bend perpendicular to the wing.</p> |
