| 摘要 |
<p>PURPOSE:To decrease resistance at a strong wind by a method wherein a sail is spread on a net mounted to a frame to form a wheel, and the sail is left flowing in the wind according to its direction or taken up on a roller at a strong wind. CONSTITUTION:A sail 4 clings to a net 3 according to the direction of a wind force 6, thus giving rise to a resistance strong against the wind. A sail 4' then comes off a net 3', on the contrary, according to the direction of the wind force 6, thus the resistance weakening against the wind. Vanes 2, 2' run around a rotary shaft 1 in the direction 7' due to an unbalance in resistance of the vanes 2, 2' against the wind. Then, a pressure receiving area of the sail against the wind can be adjusted by winding the sail on rollers 5, 5'.</p> |
