| 摘要 |
PROBLEM TO BE SOLVED: To provide a crane operating device 15 capable of selecting the independent drive of a telescopic boom 3 in a crane and hook parallel displacement control interlocked with the drive of the telescopic boom 3, with simple operation. SOLUTION: A controller 21 is provided with a mode selecting means 28 capable of selecting an independent drive mode and a hook horizontal displacement mode. When the mode selecting means 28 is changed over to the independent drive mode and a telescopic motion (derricking motion) changeover direction indicator switch 16 (17) is operated, a telescopic motion (derricking motion) control valve 4 (6) is changed over to the valve changeover indication quantity of a valve changeover quantity indicating means 19 in the indicating direction of the indicator switch 16 (17). When the mode selecting means 28 is changed over to the horizontal displacement mode and the telescopic motion (derricking- motion) changeover direction indicator switch 16 (17) is operated, the telescopic motion (derricking motion) control valve 4 (6) is changed over as mentioned above, and a winch control valve 8 is changed over to a valve changeover quantity to move a hook 12 while keeping the hanging height almost constant.
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