| 摘要 |
PURPOSE:To prevent a slip between driving rollers and an endless belt while rotating, by furnishing teeth of a gear shape along the whole length at both right and left ends of the inner surface of the endless belt contacting with rollers. CONSTITUTION:At the both right and left ends of the inner surface of an endless belt 1, teeth 11 of a gear shape are fixed longitudinally along the whole length. The gear shape teeth 11 are geared with the gear teeth arranged at the periphery of driving rollers 12, 12' which are held at the front and rear ends of the car frame 13, and at the same time, with the teeth of guide rollers 14, 14' which are placed at the adequate positions on both sides of a holding beam 4, while the belt 1 is extended in a straight line. Therefore, a pressing power to the wall by a vacuum power acts against the wall through the endless belt 1. |
