Patent · US Expired

Stiffened composite structural member and method of fabrication

US4086378A · kind A · utility

131Cited by
9References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 20, 1975
Grant dateApr 25, 1978
Priority date
Expiry dateFeb 20, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/249945
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Stiffened structural components, particularly integrally stiffened light weight shell structures, produced by molding astiffening member, preferably formed of a graphite-epoxy composition and having a so-called isogrid rib stiffening configuration, to a partially cured (B-stage) condition, injecting a suitable elastomer, e.g. a silicone, into the open spaces of the isogrid rib stiffener, to stabilize the partially cured composite during subsequent heat forming and curing operations, heat forming the resulting stiffening member to the required contour, e.g. for a cylinder into approximately 90.degree. arcuate isogrid panels, heat forming the skin of the shell structure by laying up a plurality of layers of a pre-impregnated tape within a cylindrical mold, installing a plurality, e.g. four, of the heat formed isogrid stiffening panels into the interior of the skin, co-curing the skin and the isogrid panels to form an integral stiffened shell structure, removing the cylindrical mold from the co-cured stiffened shell structure and removing the elastomer from the spaces between the isogrid rib stiffeners.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.