FIELD OF THE INVENTION

The present invention is directed to a method and apparatus for continuously molding carbon fiber reinforced polymer (CFRP) slender components.

BACKGROUND OF THE INVENTION

To reduce costs and weight of CFRP aircraft, it is typically better to have more integrated components with fewer joints and parts, and where possible, to manufacture these with a continuous production/molding system.

Continuous CFRP molding has been achieved typically with constant section, straight parts, such as rails, stringers, cross beams and the like, but where geometries vary such as fuselage frames (typically curved, even of circular shape) this is not easy in a continuous process and other processes like 1-shot press forming are often used. Expanding continuous molding to fuselage frames would create an opportunity to reduce cost and also reduce product complexity and weight by reducing the number of joints.

It is clearly possible by creating a curved mold tool to create in semi-continuous fashion a curved shape, but what has not been possible has been to create a full fuselage frame in a continuous manner. Either the frame has to be cut into multiple parts, requiring several joints adding weight and assembly costs, and/or the process is simply not continuous as it has to avoid the possibility that the geometry causes a clash with the mold tooling or associated equipment.

SUMMARY OF THE INVENTION

An embodiment of the invention comprises a method for forming a continuously molded carbon fiber reinforced polymer slender curved component. Steps of the method include:

directing a continuous supply of uncured carbon fiber reinforced polymer material into a forming tool,

continuously molding the uncured carbon fiber reinforced polymer material into a desired shape in the forming tool,

curing the carbon fiber reinforced polymer material into a component of the desired shape in the forming tool,

removing the component from the forming tool, and

putting an out-of-plane curvature in the component.

In an embodiment, the out-of-plane curvature is put into the component while the carbon fiber reinforced polymer material is in the forming tool.

In an embodiment, the out-of-plane curvature is put into the component after the carbon fiber reinforced polymer material has been removed from the forming tool.

In an embodiment, the method includes cutting the component into a component part of a desired length.

In an embodiment, the method includes a further heating and re-curing process to eliminate the out-of-plane curvature after the component has been cut into the component part.

The invention also comprises an apparatus for forming a continuously molded carbon fiber reinforced polymer slender curved component. The apparatus includes a forming tool configured to receive a continuous supply of uncured carbon fiber reinforced polymer material, the forming tool having a shape conforming to a desired shape for the carbon fiber reinforced polymer slender curved component, an arrangement for at least partially curing the carbon fiber reinforced polymer material into a component, and an arrangement for putting an out-of-plane curvature in the component.

In an embodiment, the arrangement for putting an out-of-plane curvature in the component comprises a curvature built into the forming tool.

In an embodiment, the arrangement for putting an out-of-plane curvature in the component comprises a series of rollers arranged downstream of the forming tool to receive the at least partially cured component and to deflect the at least partially cured component out of a plane in which the carbon fiber reinforced polymer is directed through the forming tool.

In an embodiment, the apparatus further comprises a tool for cutting the component into a component part of a desired length.

In an embodiment, the apparatus further comprises a tooling jig configured to receive the component part and a heater configured to heat and re-cure the component part to eliminate the out-of-plane curvature.

