US 12,226,961 B2
Preform charges and fixtures therefor
Erick Davidson, Piedmont, CA (US); Ethan Escowitz, Berkeley, CA (US); Riley Reese, Carpinteria, CA (US); Sean Hennessee, San Francisco, CA (US); and J. Scott Perkins, Berkeley, CA (US)
Assigned to Arris Composites Inc., Berkeley, CA (US)
Filed by Arris Composites Inc., Berkeley, CA (US)
Filed on Oct. 11, 2019, as Appl. No. 16/600,131.
Claims priority of provisional application 62/744,822, filed on Oct. 12, 2018.
Prior Publication US 2020/0114596 A1, Apr. 16, 2020
Int. Cl. B29C 70/46 (2006.01); B29B 11/16 (2006.01); B29C 65/00 (2006.01); B29C 70/68 (2006.01)
CPC B29C 66/1122 (2013.01) [B29B 11/16 (2013.01); B29C 70/46 (2013.01); B29C 70/467 (2013.01); B29C 70/68 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for forming a fiber-composite part, the method comprising:
forming a preform charge using a preform-charge fixture, the preform charge fixture comprising a first cavity, wherein the preform charge is sized and shaped to match a form of a mold cavity of a compression mold, wherein forming the preform charge comprises:
A. stacking, one upon another, a requisite amount of preforms in the first cavity, each preform consisting essentially of a segment of towpreg, the segment of towpreg comprising a bundle of fibers having a cross section of substantially circular or oval shape, wherein the bundle of fibers are impregnated with a polymer resin, the stacking of preforms resulting in an assemblage, the assemblage having a desired fiber alignment and a first geometry dictated by a shape of the first cavity;
B. immobilizing the preforms in the assemblage;
C. after forming the assemblage and immobilizing the preforms therein, softening the preforms, if required due to their chemical composition, thereby causing at least some neighboring preforms in the assemblage to tack together to form the preform charge, while maintaining the desired fiber alignment;
removing the preform charge from the first cavity of the preform charge fixture;
placing the preform charge into the mold cavity of the compression mold, whereby, by virtue of the size and shape of the preform charge, the preform charge registers to the mold cavity;
closing the mold cavity; and
compression molding the preform charge by subjecting the preform charge to elevated temperature and pressure sufficient to fully consolidate the fibers and resin therein, thereby fabricating a fiber-composite part.