| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase the degree of freedom in selecting the installation position while making a mast and a foundation portion small. SOLUTION: In a tower crane in which the mast 4 is provided, a derrickable jib 5 is provided on an upper portion of the mast 4 in a vertically oscillating manner, a derricking apparatus 6 to oscillate the derrickable jib 5 upward by winding an oscillating rope R1 connected to the derrickable jib 5 is provided, and a hoisting apparatus 8 to hoist a work 7 to be hoisted located below the derrickable jib 5 by winding a hoisting rope R2 installed via the derrickable jib 5, the derricking apparatus 6 is disposed on a lower end side of the mast 4, and the oscillating rope R1 is disposed within the mast 4.</p> |
