Molded laminated structure with negative draft angles and associated methods of manufacturing

Patent metadata

Field	Value
Publication number	US-2021237378-A1
Application number	US-202016781640-A
Country	US
Kind code	A1
Filing date	Feb 4, 2020
Priority date	Feb 4, 2020
Publication date	Aug 5, 2021
Grant date	—

Abstract

Disclosed herein is a molded laminated structure having negative draft angles and methods of manufacturing a molded laminated structure having negative draft angles. A preliminary structure having a first outer layer and a second outer layer is molded with a bend that divides the preliminary structure into two sections with an angle between the two sections of less than 180-degrees. Portions that extends from the sections are at positive draft angles. A groove is formed in the preliminary structure at the bend but not formed in a constant cross-section of the second outer layer. The preliminary structure is folding along the bend to at least partially close the groove and form a molded laminated structure with portions that extend at a negative draft configuration while retaining the second outer layer continuous throughout the molded laminated structure.

First claim

What is claimed is:

1 . A molded laminated structure comprising:
a first outer layer, defining a first outer surface; a second outer layer, defining a second outer surface, wherein the first outer surface is opposite the second outer surface; an intermediate portion; a first portion, extending from the intermediate portion at a first negative draft angle relative to a horizontal plane; a second portion, extending from the intermediate portion towards the first portion at a second negative draft angle relative to the horizontal plane, wherein the first portion and the second portion are at opposite ends of the intermediate portion and the first portion extends towards the second portion; a groove formed in the first outer layer and extending across an entirety of the intermediate portion along a folding joint between the first portion and the second portion, wherein the groove is not formed in a constant cross-section of the second outer layer such that the second outer layer is continuous across a constant cross-section of the intermediate portion along the groove; and an adhesive filling the groove.

2 . The molded laminated structure of claim 1 , wherein the groove further comprises:
a first wall, extending from the first outer surface and through the first outer layer; a second wall, opposite the first wall, and extending from the first outer surface and through the first outer layer; and an exposed section of the second outer layer between the first wall and the second wall.

3 . The molded laminated structure of claim 2 , further comprising:
a notch, formed in the second outer surface and extending across an entirety of the intermediate portion along the folding joint; and a filler material, within the notch.

4 . The molded laminated structure of claim 1 , further comprising a honeycomb core, interposed between the first outer layer and the second outer layer.

5 . The molded laminated structure of claim 1 , wherein the first outer layer and the second outer layer each comprises a glass-fiber-reinforced polymeric material.

6 . The molded laminated structure of claim 5 , wherein the second outer layer comprises four or less plies of glass-fiber-reinforced polymeric material.

7 . The molded laminated structure of claim 1 , wherein the first outer layer and the second outer layer each comprises a carbon-fiber-reinforced polymeric material.

8 . The molded laminated structure of claim 1 , wherein the structure is an aircraft structure.

9 . A method of manufacturing a molded laminated structure, the method comprising steps of:
molding a preliminary structure, wherein the preliminary structure comprises:
a first outer layer, defining a first outer surface;
a second outer layer, defining a second outer surface, wherein the first outer surface is opposite the second outer surface;
an intermediate portion, comprising a bend that divides the intermediate portion into a first section and a second section, wherein the first section, proximate the bend, is angled relative to the second section, proximate the bend, such that the second outer surface of the first section defines an angle with the second outer surface of the second section that is less than 180-degrees; and
a first portion, extending from the first section at a first positive angle relative to a horizontal plane; and
a second portion, extending from the second section away from the first portion at a second positive angle relative to the horizontal plane, wherein the first portion extends away from the second portion;
machining a groove into the first outer layer that extends across an entirety of the intermediate portion along the bend, wherein the groove is not formed in a constant cross-section of the second outer layer such that the second outer layer is continuous across a constant cross-section of the intermediate portion along the groove; filling the groove with an adhesive; and folding the intermediate portion at the bend to at least partially close the groove such that the first portion extends towards the second portion at a first negative draft angle relative to the horizontal plane and the second portion extends towards the first portion at a second negative draft angle relative to the horizontal plane.

10 . The method of claim 9 , wherein:
the groove of the preliminary structure has a cross-section, along a plane perpendicular to the bend comprising:
a first wall, extending from the first outer surface and into the first outer layer;
a second wall, opposite the first wall, and extending from the first outer surface and into the first outer layer; and
an exposed section of the second outer layer between the first wall and the second wall; and
the step of folding the intermediate portion at the bend at least partially closes the groove by folding the first wall towards the second wall, and the second wall towards the first wall.

11 . The method of claim 10 , wherein:
the exposed section of the second outer layer between the first wall and the second wall is radiused; and a radius of the exposed section is at least 7 times a thickness of the second outer layer.

12 . The method of claim 10 , wherein:
the exposed section of the second outer layer between the first wall and the second wall is radiused; and a radius of the exposed section is no more than 10 times a thickness of the second outer layer.

13 . The method of claim 10 , further comprising filling a notch formed in the second outer surface and extending across an entirety of the intermediate portion along the bend with a filler material, wherein the notch is formed in the second outer surface, opposite the exposed section of the second outer layer, during the step of folding the preliminary structure at the bend.

14 . The method of claim 9 , wherein:
the groove of the preliminary structure has a cross-section, along a plane perpendicular to the bend, that has a first V-shape; and the step of folding the intermediate portion at the bend at least partially closes the groove such that the cross-section of the groove, after folding the intermediate portion at the bend, has a second V-shape different than the first V-shape.

15 . A method of manufacturing a molded laminated structure, the method comprising steps of:
molding a preliminary structure, wherein the preliminary structure comprises:
a first outer layer, defining a first outer surface;
a second outer layer, defining a second outer surface, wherein the first outer surface is opposite the second outer surface;
a honeycomb core interposed between the first outer layer and the second outer layer;
an intermediate portion, comprising a bend that divides the intermediate portion into a first section and a second section, wherein the first section, proximate the bend, is angled relative to the second section, proximate the bend, such that the second outer surface of the first section defines an angle with the second outer surface of the second section that is less than 180-degrees;
a first portion extending from the first section at a first positive angle relative to a horizontal plane; and
a second portion extending from the second section, away from the first portion, at a second positive angle relative to the horizontal plane; wherein the first portion extends away from the second portion;
machining a groove into the first outer layer that extends across an entirety of the intermediate portion along the bend, wherein the groove is not formed in a constant cross-section of the second outer layer such that the second outer layer is continuous across a constant cross-

Assignees

• Boeing Co

Inventors

• Wirrick Jeffrey

Classifications

• B29C70/30

  Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core · CPC title

• B64C1/066

  Interior liners · CPC title

• B32B3/30

  characterised by a layer formed with recesses or projections, e.g. {hollows, grooves, protuberances, ribs (apertured layer B32B3/266; layer with cavities or internal voids B32B3/26)} · CPC title

• B32B3/12

  characterised by a layer of regularly- arranged cells, e.g. a honeycomb structure · CPC title

• B32B2605/18

  Aircraft · CPC title