| 摘要 |
<p>PURPOSE:To obtain a high efficiency at all times in spite of wind speed and wind direction by a method wherein a blade is mounted to a blade mounting shaft projected radially around a rotary shaft so as to be rotatable around the mounting shaft in order to permit to change the angle of the blade freely within a predetermined range. CONSTITUTION:In the propeller type windmill, provided with two sheets of blades, for example, attached to the rotary shaft 2 so as to be extended to the diametral direction thereof, the blade mounting shaft 11 is projected into the diametral direction of the rotary shaft and the blade 1, having an aerofoil type, is mounted rotatably to the mounting shaft 11 through a bearing 12. The blade 1 is divided into some pieces in the lengthwise direction in accordance with necessity so as to be rotatable mutually. The blade 1 pivots in accordance with the angle of incidence of air even if the wind speed or the wind direction is changed suddenly and the relative angle of incidence is changed. According to this method, the sudden change will never be caused in the lift of the blade and the efficiency may be obtained at all times.</p> |
