| 摘要 |
METHOD AND APPARATUS FOR MAKING PREFORMS A directed fiber, directed energy process provides both a method and an apparatus for making structural preforms. Fibrous reinforcement material is chopped into short lengths of fiber and propelled toward a perforate mold part. During propulsion and/or deposition on the perorate mold part the fibers are sprayed with an electromagnetic radiation-curable binder. The bindercarrying fibers are held on the perforate mold part by a flow of air in that the perforate mold part is rotatably mounted in a plenum which provides an air flow therethrough. Rotation of the perforate mold part and scanning action of the fiber and binder propelling mechanisms effects even and complete coverage of the perforate mold part. After a mat of the chopped fibers has been applied to the perforate mold part, a conforming second mold part closes the mold and presses the fibers to replicate the shape of the three dimensional rigid preform. While in the mole which may be advantageously constructed of an electromagnetic radiation transmissive material, the pressed fibers are subjected to electromagnetic radiation to cure the binder and bond the fibers of the mat into a rigid three-dimensional element. A subassembly, such as an auxiliary member or members, may be attached by applying an electromagnetic energycurable binder to a selected area of the preform and/or the subassembly, placing the auxiliary member into a desired orientation and into intimate contact with the preform at the selected binder-coated area, and the binder at that area cured by the application of the electromagnetic energy. The electromagnetic energy may be, for example, microwave radiation and/or ultraviolet radiation. |
