Method and apparatus for producing off-axis composite prepreg material

Abstract

The invention is directed to a method and apparatus for preferably producing a two layer off-axis composite prepreg material in tape form that has fiber direction at angles such as plus or minus five degrees to the longitudinal direction of the backing paper. The use of such off-axis prepreg composite material tape is primarily for fabricating high length-to-width ration parts such as composite wing stringers or spars for aircraft.

Description

BACKGROUND OF THE INVENTION[0001]1) Field of the Invention[0002]The invention relates to composite material, and more specifically to a method and apparatus for producing off-axis composite prepreg material for fabricating composite parts for aircraft.[0003]2) Description of Related Art[0004]Known methods and apparatuses exist for producing multi-ply tape and fabricating cross-plied structural material. Such known methods include using many layers of carbon tape with standard ply angle fiber orientations, such as 0 degree, plus and minus 45 degree, and 90 degree. Newer investigations indicate that there may be very significant weight savings using nonstandard ply angle fiber orientation, such as plus and minus 5 degree, and plus and minus 65 degree ply angle orientations for aircraft composite parts. The 65 degree ply angle orientations can easily be laid down with existing equipment. However, the plus and minus 5 degree ply angle orientation causes difficulty for current lay-up pro...

AI Technical Summary

Benefits of technology

[0007]The invention satisfies this need for an improved method and apparatus for producing off-axis composite prepreg material, as well as provides a unique, nonobvious, and advantageous method and apparatus for producing off-axis composite prepreg material. None of the known methods and devices provides all of the numerous advantages of the invention. Unlike known methods and devices, the method and apparatus for producing off-axis composite prepreg material provides the following advantages: it provides a method and apparatus for producing a two layer uni-directional off-axis composite prepreg material in narrow tape form that has the fiber direction at low angles, i.e., approximately plus or minus 5 degrees to the longitudinal direction of the backing paper; it provides a method and apparatus that produces rolls of composite prepreg material that have several plies of various fiber orientations; it provides a method and apparatus that can improve the productivity of laying up parts because several plies can be placed at one time rather than individually; it provides a method and apparatus that simplifies the lay-up machinery required because separate cross-ply laminations may not be required, since the cross-plies are incorporated into the laydown material; and it provides a method and apparatus that efficiently and less expensively produces off-axis tape primarily for fabricating high length-to-width ratio parts, such as composite wing stringers or spars for aircraft. Because the off-axis tape can be applied along the length of the part, it avoids large quantities of triangular prepreg scrap caused by running unidirectional prepreg tape off the part boundaries. In addition to the waste of material, running off the edge of the part adds to machine running time.

Problems solved by technology

In addition to the waste of material, running off the edge of the part adds to machine running time.

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