| 摘要 |
PURPOSE:To keep spaces among the fences constant even when the float fences are multiple-stretched by making the floats on the windward side or the upstream side to the direction of a wind or a water stream side smaller than the floats on the leeward or downstream side. CONSTITUTION:On a direction of a wind shown in the arrow A, the float fence B consisting of the float 1 and a hanging tail 2 is fixed by an anchor 3. The float fence C consisting of the float 4 and a hanging tail 5 is stretched on the leeward or downstream side from the fence B. The fences B and C are connected by a holder 6 in order to keep the space between the fences B and C constant. Accordingly, since the float C is subject to wind pressure or the water stream more than the float B by the wind force or the water stream of the direction of the wind or the water stream the float C is pulled strongly to the leeward or downstream side and the holder 6 is brought to a tensed state, and the space between the fences B and C can be kept constant. |
