| 摘要 |
PURPOSE:To protect a driver from erroneous operation or biwilderment, by splitting the entire turning angle of upper turning body into predetermined turning angle range then functioning an electric switching means accordingly to indicate the operating direction of operating means of travel car. CONSTITUTION:A semi-circular cam 14 is arranged on the front half section of lower travel body 1 around the center of rotation while a limit switch 10S is fixed on the upper turning body 2 contactably with said cam 14. Then, with correspondence to opening/closing of the limit switch 10S, one of two sets of indication lamps comprised of a combination of advance indication lamps 11F, 12F and back indication lamps 11B, 12B is lighted to display advance/back with relation to an operating lever on an operating stand. Consequently, turning of upper body will never cause erroneous operation nor biwilderment for the operator. |
