Method of making a waffle stiffener
AssigneeLockheed Martin Corporation
InventorsRoss A. Benson, Terrance R. Burd, Todd H. Ashton
Life of this patent
Estimating the term…
Abstract
An apparatus and method for stiffening a panel provides a composite waffle stiffener and the method for constructing the stiffener. A plurality of fabric plies pre-cut to a selected pattern are laid on a tool having a waffle configuration, the plies overlapping each other to maintain continuity of the structure. The resulting waffle stiffener is then bonded to a panel requiring stiffening. The stiffener is flexible and may be bonded to curved panels. Holes in the stiffener allow access to the volume between the stiffener and the panel for minimizing volume loss within, for example, a wing structure containing fuel and for ventilating air or moisture trapped in the volume.
Claims14
A method of constructing a composite waffle stiffener, comprising:
- forming a die having a waffle configuration, the waffle configuration being a plurality of generally-parallel first webs extending in a first direction and a plurality of generally-parallel second webs extending in a second direction and intersecting the first webs to form pockets, each pocket having four sidewalls and a base;
- then
- layering a plurality of fabric plies on the die, the fabric plies conforming to the waffle configuration and having cap regions defined by crests of the first and second webs;
- and
- disposing a plurality of unidirectional cap plies between the fabric plies such that the unidirectional cap plies extend along the cap regions in the first direction.
A method of constructing a composite waffle stiffener, comprising:
- forming a die having a waffle configuration, the waffle configuration being a plurality of generally-parallel first webs extending in a first direction and a plurality of generally-parallel second webs extending in a second direction and intersecting the first webs to form pockets, each pocket having four sidewalls and a base;
- then
- layering a plurality of fabric plies on the die, the fabric plies conforming to the waffle configuration and having cap regions defined by crests of the first and second webs;
- and
- disposing a plurality of unidirectional cap plies between the fabric plies such that the unidirectional cap plies extend along the cap regions in the first direction and the second direction.
Dependencies are inferred from the claim text.