| 摘要 |
An attachment device comprises a conical screw and a hook which fits thereto with a curved center portion having a slot extending in the length direction of the hook. A plate can be engaged in said slot so that an aperture in the plate located near the edge thereof partly reaches inside the hook, whereafter the screw can be inserted therein. The screw then engages the edge of the aperture and the concave portion of the hook. The hook itself is inserted through an aperture in a rail and is held against one of its sides, so that the plate is drawn perpendicularly against the opposite side of the rail. |
