| 摘要 |
<p>PROBLEM TO BE SOLVED: To keep the stability of an operator's body in the operation in a standing posture of high workability and visibility, and simultaneously reduce the fatigue caused by the driving operation. SOLUTION: A back rest device 30 is mounted on a back plate 23 at a rear part of a driver's seat 11. A back rest part 54 provided with a cushioning material 37 at its tip part is pivoted to an upper part of a fixing plate 31 forming the back rest device 30, rotatably by a rotary shaft 55. The cushioning material 37 is located at a lower part by the rotary shaft 55 when the back rest part 54 is fallen down, and a first arm 33 of the back rest part 54 is attracted to a magnet 67 to temporarily fix the back rest part 54 when the back rest part 54 is raised. The fixing plate 31 can be arbitrarily vertically positioned to the back plate 23, and a second arm 35 provided with the cushioning material 37 is longitudinally slidable to the first arm 33.</p> |
