| 摘要 |
<p>[Problem] To make a rotary blade and a wind direction parallel with each other by use of wind during a strong wind. [Solution] First to third rotary blades (3 to 5) are attached to a rotatable rotating body (2) so as to be centered on a revolution shaft (1). A wind direction shaft (6) is rotatable with respect to the revolution shaft (1) according to the direction of wind force against a wind direction plate (61). A fixed sprocket (7) is fixed to the wind direction shaft (6). A key driving mechanism (13) allows a first key member (11) to be engaged into the respective first engaging portions (81, 91) of first and second movable sprockets (8, 9) at a normal time. In this state, the rotating body (2) can be rotated by the wind received by the rotary blades (3 to 5). During a strong wind, the first key member (11) is pulled out from the respective first engaging portions (81, 91). A second key member (12) is then engaged into the respective second engaging portions (82, 92) of the first and second movable sprockets (8, 9). In this state, each of the rotary blades (3 to 5) becomes parallel with a wind direction.</p> |
