| 摘要 |
PURPOSE:To relieve a labor, by a method wherein a hook is rotatably located to the lower part of a support bracket situated to the lower part of a body, and a fulcrum part is positioned between the actuating point side and the point of force side of the body so that a set position is regulatable. CONSTITUTION:After a support bracket 15 is brought near to the hook 3 side to set a lever ratio to a high value, the hook 3 is inserted into a hatch 31d of a manhole cover 30, and a locking groove is engaged with the hatch 31d. The point of force 2a side of a body 2 is depressed downward to lift up the cover 30. The bracket 15 is moved to the portion, most closer to the point of force 2a, of a fulcrum regulating part 2C to set a lever ratio to a low value. The point of force 2a is further depressed to push up the one end of the cover 30, and after a roller is inserted under the cover 30,the cover 30 is pulled out by pulling the point of force 2a side. |
