Structural composite preform wet-out and curing system and apparatus
In accordance with one embodiment of the present invention, the invention comprises a continuous structural composite preform wet out system and apparatus which takes as an input pre-formed structural composite structures with a structural foam core, passes these structures through a wetting system which may comprise sprayers, brushes, a die or dies, or other wetting means; applies a cure process such as ultraviolet light, heat, curing agent or other cure method, and produces a completed, cured structural composite structure such as a beam or panel for use in any structure as desired by the user. The improved structural composite wet out system of the invention provides run rate, ease of use, structure efficiency and handling advantages over the pultrusion systems of the prior art by achieving higher production rates, the ability to use light cure resins and the ability to produce composite structures of non-uniform cross-section.
1. A system for producing a composite structure, comprising:
a conveyor for motivating a composite preform along a longitudinal axis of motivation, wherein said composite preform is defined as having a structural foam core at least partially covered with an unwetted fabric attached to said foam core;
a wetting station comprising a plurality of spray heads in fluid communication with a controllable resin pump via a first resin conduction means, and wherein said resin pump is in fluid communication with a resin reservoir containing resin via a second resin conduction means;
a cylindrical mandrel for shaping the composite preform:
a curing station; and
a resin collection sump system comprising a sump basin for collecting excess resin as it drains away from said wetting station, said sump basin in fluid communication with a sump pump, and said sump pump being in fluid communication with a reservoir, and said reservoir being in fluid communication with said wetting means via said resin pump;
wherein:
said wetting station, said cylindrical mandrel, and said curing station are each located along said longitudinal axis of motivation, such that said composite preform is motivated by said conveyor to pass through said wetting station first, then wrapped around the cylindrical mandrel in a tight spiral on the cylindrical mandrel, and then through said curing station;
a resin flow rate through the plurality of spray heads is controlled by the controllable resin pump such that said unwetted fabric is saturated with resin by the plurality of spray heads when said controllable resin pump motivates said resin from said resin reservoir to the plurality of spray heads while said composite preform is motivated through said wetting station by said conveyor;
the plurality of spray heads being disposed both above and below the conveyor, so as to spray resin onto opposing surfaces of said composite preform as said composite preform is motivated along said longitudinal axis of motivation through said wetting station, such that unwetted fabric on both opposing surfaces is saturated with resin;
said curing station is disposed to at least partially cure said resin while said composite preform is motivated through said curing station by said conveyor; and
wherein said conveyor is further defined as a motor-driven conveyor.
2. The system of claim 1 , wherein said foam core is further defined as a self-expanding foam that has been injected into a forming die while applying said fabric such that interstitial spaces in said fabric are filled with said self-expanding foam.
3. The system of claim 1 , wherein said curing station is further defined as comprising a heating element disposed so as to radiate heat energy onto said composite preform as said composite preform is motivated along said longitudinal axis of motivation through said curing station.
4. The system of claim 1 , wherein said curing means is further defined as at least one lighting element disposed so as to radiate light energy onto said composite preform as said composite preform is motivated along said longitudinal axis of motivation through said wetting station.
5. The system of claim 1 , wherein said curing means is further defined as at least one ionizing radiation source disposed so as to radiate ionizing radiation onto said composite preform as said composite preform is motivated along said longitudinal axis of motivation through said wetting station.
6. The system of claim 4 , wherein said composite preform is characterized by cross-sections of different sizes and shapes taken at different locations along said composite structure.
7. The system of claim 5 , wherein said composite preform is characterized by cross-sections of different sizes and shapes taken at different locations along said composite structure.