| 摘要 |
PURPOSE:To prevent metallic sounds caused by rotation and noises caused by oscillation by attaching a plastic thin plate to one side or both sides of a blade or coating it with a plastic solution and drying to cover it with a film of required thickness. CONSTITUTION:A fan blade has been produced considering such factors as cutting the air thoroughly and reducing its weight by using a thin plate as far as possible, but some faults are caused, during its use, e.g., metallic sounds peculiar to the metal blade are generated and also noises are generated as a result of unstability for high speed rotation. Therefore, a blade 1 is made of an extremely thin metal plate, and a plastic thin plate 2 is attached or bonded to it or it is coated with a plastic film 3, thereby a light and firm fan blade can be available. |
