| 摘要 |
PURPOSE:To freely travel at a place having an obstacle such as a high wall by automatically shrinking a support foot with a shrinking device when detecting the obstacle in front of support foot. CONSTITUTION:Frame support feet 2 protruding downward and vertically shrink able are fitted to a frame 1 at a fixed distance longitudinally. A travel wheel 4 is suspendedly supported at the lower end of a support foot 2 via a shrinkable spring 3. The travel wheel 4 has a wheel drive motor so as to allow self- propulsion and can be vertically shrunk by a hydraulic jack motor. A wheel front detecting switch 10 detecting an obstacle directly before the travel wheel 4 is arranged in front of each travel wheel 4. When the switch 10 is operated, a wheel shrinking device is automatically operated to lift the wheel. |
