| 摘要 |
PURPOSE:To protect a blade against damage due to resonance without changing the speed of rotation of the blade, by applying a resin coating partially over the outer surface of a blade made of a resin, and thereby changing the rigidity and the moment of inertia of the blade. CONSTITUTION:The characteristic frequency of a blade made of a resin 2 is changed by applying a coating of a resin 7 over the outer surface of the blade at its root portion and thereby increasing the rigidity of the blade in particular. As the properties of the resin 7, it is required to have a good affinity for the outer surface of the blade made of the resin 2, so that it can be bonded to the outer surface of the blade with ease and firmly. With such an arrangement, the characteristic frequency of the blade can be changed in a desired manner by appropriately selecting the material of resin 7, coating area of resin 7, thickness of the coating, repairing position, etc. |
