| 摘要 |
<p>The ventilator's rotor, formed by several separate parts made of synthetic material, has a cylindrical-shape metallic hub with its bottom surface sunk in a synthetic material ring to which the fan blades are fixed. The cylindrical part of the hub has grooves or holes into which fit the bases of the detachable blades, and its front edge has means to lodge a locking ring. The blades' bases have a fixation part which together with the cylindrical hub and the locking ring are, at least in part, sunk in the synthetic material crown. The blades are typically locked by rotation 180 deg. about their longitudinal axes.</p> |
