| 摘要 |
PURPOSE:To prevent an accident of falling of an operator and as well an accident of roll-down of a working vehicle due to an inclination of the vehicle, by providing sensors for detecting variations in the height of the ground surface around the working vehicle so that alarm is issued in accordance with the result of the detection and then, the vehicle is stopped. CONSTITUTION:Transmitting and receiving units 5l, 5r which are used as ultrasonic distance sensors, are attached to the right and left sides of the rear side surface of a working vehicle with their transmitting and receiving surfaces being directed downward. When one of the transmitting and receiving units detects a condition that the ground level in the rear of the vehicle is relatively lower, alarm alone is issued, and when the further lower ground level is detected, the engine is stopped with the issuance of alarm to stop the vehicle. Further, when both sensors 5l, 5r detect a condition that the ground level rear of the vehicle is low, the engine is stopped to inhibit the vehicle from travelling, and as well a warning lamp and a warning buzzer are actuated. |
