| 摘要 |
<p>A composite type fan with low noise fan blades includes a hub and several long blades equally spaced around the circumference of the hub. A base ring is surrounded and connected with the end of the long blades integrally. The inner wall of the base ring located between the spaced long blades is secured at least one short blade, which has windward curved surface in the same orientation with the long blade. To improve the whole intake surface of the blade by means of arranging synchronous rotational short blades in the outer periphery of the long blades,, accordingly, the air can go uniformly through every point on the blades. The technical solution can reduce noise caused by the air contacts with the blades rotating in high speed. The design is scientific and the structure is reasonable and simple. It is to be noted that the fan can reduce noise apparently to compare the invention with the traditional one in same rotation speed and wind amount. In addition, the wind guiding passage arranged in the outer of the axial-flow fan blades can be omitted.</p> |
