| 摘要 |
PROBLEM TO BE SOLVED: To prevent damage to a hook storage device 14 or the like by a shock when a two-speed hydraulic motor 3 is wound and driven in a high-speed drive state and causes collision of a hook block 5 against a boom tip part 4a in storage operation for the hook block 5, in a winch device 1 allowing a change between low-speed drive and high-speed drive by the motor 3. SOLUTION: This controller has a hook proximity state detection switch 20 detecting proximity of the hook block 5 to the boom tip part 4a within a prescribed length L; and a displacement switching limitation means 21 receiving a detection signal of the switch 20 and disabling the switching of a high and low speed selector valve 11 to a small displacement side b.
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