| 摘要 |
PROBLEM TO BE SOLVED: To reduce a load acting on a connecting part between a connecting winch unit and a swivel base, by reducing the moment acting on the connecting winch unit. SOLUTION: A boom 6 having a top sheave on the tip is arranged on the swivel base 5. The connecting winch unit 12 is rotatably connected to an end part of the swivel base 5. A sheave support member 25 for supporting a lower sheave 32b is rotatably connected to the connecting winch unit 12. The sheave support member 25 is positioned above the connecting winch unit 12 and the swivel base 5, and contacts a load support part 31 with an upper surface of the swivel base 5. When back tension is made to act by winding a second rope 15 wound on a second winch 14 between the top sheave and the lower sheave 32b, the moment trying to pull up the connecting winch unit 12 with the load support part 31 as a fulcrum, acts on the sheave support member 25. COPYRIGHT: (C)2011,JPO&INPIT |
