Application of gap fillers during layup of charges of composite material
Systems and methods are provided for shaping flat charges. One embodiment is a forming system for shaping a flat charge. The forming system includes female dies that are elongate and are configured to hold the flat charge, and a male die that is elongate and is configured to press into the flat charge between the female dies to form the flat charge while the flat charge is supported, the male die includes notches that extend along a length of the male die and are dimensioned to retain gap fillers of the flat charge at widthwise locations of the flat charge corresponding to corners at the female dies while the flat charge is formed.
1. A forming system for shaping a flat charge, comprising:
a flat charge having gap fillers disposed atop the flat charge;
female dies that are elongate and are configured to hold the flat charge; and
a male die that is elongate and is configured to press into the flat charge between the female dies to form the flat charge while the flat charge is supported, the male die comprising notches that extend along a length of the male die and are dimensioned to retain the gap fillers of the flat charge at widthwise locations of the flat charge corresponding to corners of the female dies while the flat charge is formed,
wherein the gap fillers of the flat charge are disposed widthwise beyond the notches of the male die, and
wherein the gap fillers of the flat charge slide widthwise into the notches as the flat charge is pressed between the male die and the female dies.
2. The forming system of claim 1 wherein:
internal corners within each of the notches are at least ninety degrees.
3. The forming system of claim 1 wherein:
each of the widthwise locations becomes a corner of a preform after forming of the flat charge has completed.
4. The forming system of claim 1 wherein:
each notch bridges one of the corners of the female dies.
5. The forming system of claim 1 further comprising:
feet that pinch the flat charge against the female dies.
6. The forming system of claim 1 wherein:
the female dies include suction ports configured to apply suction that holds the flat charge during forming of the flat charge.
7. The forming system of claim 1 wherein:
the male die and the female dies are configured to form the flat charge into at least one shape selected from the group consisting of: a U shape, a trapezoidal shape, and an omega shape.
8. A method for shaping a flat charge, comprising:
disposing female dies that are elongate and are configured to hold the flat charge at a forming system;
placing the flat charge at the female dies;
disposing gap fillers atop the flat charge;
supporting the flat charge at the female dies;
pressing a male die that is elongate into the flat charge between the female dies to form the flat charge while the flat charge is supported; and
retaining the gap fillers atop the flat charge within notches that extend along a length of the male die, at widthwise locations of the flat charge corresponding to corners of the female dies, while the flat charge is formed into a preform,
wherein the gap fillers atop the flat charge are disposed widthwise beyond the notches of the male die, and
wherein the gap fillers atop the flat charge slide widthwise into the notches as the flat charge is pressed between the male die and the female dies.
9. The method of claim 8 further comprising:
inserting a bladder into the preform between the gap fillers.
10. The method of claim 8 wherein:
placing the flat charge comprises placing layers of composite material.
11. The method of claim 8 further comprising:
transporting the preform, including the gap fillers, to a mandrel.
12. The method of claim 8 further wherein:
forming the flat charge comprises enforcing a shape selected from the group consisting of: a U shape, a trapezoidal shape, and an omega shape.
13. The method of claim 8 further comprising:
placing the preform formed from the flat charge into contact with a skin preform.
14. The method of claim 13 further comprising:
co-curing the preform to the skin preform.
15. A forming system for shaping a flat charge, comprising: a flat charge configured to receive gap fillers on a top surface of the flat charge; a robot arm controlled to dispense the gap fillers atop the flat charge; female dies that are elongate and are configured to hold the flat charge; and a male die that is elongate and is configured to press into the flat charge between the female dies to form the flat charge while the flat charge is supported, the male die comprising notches that extend along a length of the male die and are dimensioned to retain the gap fillers of the flat charge at widthwise locations of the flat charge corresponding to corners of the female dies while the flat charge is formed, wherein the gap fillers of the flat charge are disposed widthwise beyond the notches of the male die, and wherein the gap fillers of the flat charge slide widthwise into the notches as the flat charge is pressed between the male die and the female dies.
16. The forming system of claim 15 wherein:
a majority of the gap filler by weight comprises a curable resin.
17. The forming system of claim 15 further comprising:
a laminator configured to lay up a layer of the flat charge in coordination with other laminators.
18. The forming system of claim 15 wherein:
the flat charge is configured for shaping into a preform for a stringer of an aircraft.
19. The forming system of claim 15 wherein:
the robot arm adheres the gap filler to the flat charge by pressing the gap filler into the flat charge.
20. The forming system of claim 15 wherein:
the robot arm dispenses the gap filler along a length of the flat charge at the widthwise location.