| 摘要 |
PROBLEM TO BE SOLVED: To provide an expansion support capable of reducing a labor in lifting operation and having superior operability. SOLUTION: This expansion support is provided with a square pole fixed support 1, a square pole and hollow first movable support 3 internally fitted into the hollow part of the fixed support 2, a square pole and hollow second movable support 4 internally fitted into the hollow part of the first movable support 3, and a square pole and hollow third movable support 5 internally fitted into the hollow part of the second movable support. The hollow part of the fixed support 2 is equipped with a first coil spring S1 for applying an upward energizing force to the first movable support 3 and the hollow part of the first movable support 3 is equipped with a second coil spring S2 for applying an upward energizing force to the second movable support 4 respectively. The first movable support 3 and the third movable support 5 are provided with height position adjusting means respectively. |
