Contoured composite stringers

US11660830B2 · kind B2 · utility

Assignee

• The Boeing Company · US

Inventors

• Daniel M. Rotter · Lake Forest Park, US
• Lisa Christina Carlson · Auburn, US
• Brad Andrew Coxon · Everett, US
• Hyukbong Kwon · Marysville, US
• Khanh Mai Pham · Renton, US
• Darrell D. Jones · Mill Creek, US
• Brian G. Robins · Renton, US

Key dates

• Filing date: Jan 18, 2019
• Grant date: May 30, 2023
• Expiry date: Mar 25, 2042

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T50/40
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Aircraft that incorporates a rounded-hat composite stringer connected to an inner side of the skin of the aircraft to form an elongate conduit that defines a conduit axis, where the conduit axis includes at least one curving portion. The rounded-hat composite stringer can be manufactured by constructing a lower forming die and an upper forming die, each forming die having a length and defining a curve along at least a portion of the length of the die, cutting a pre-cured flat composite charge dimensioned to form the rounded-hat composite stringer, pressing the flat composite charge between the lower and upper forming dies to shape the composite charge into a pre-formed stringer having an inner side between curved fillet portions, contacting a forming member against the inner side of the pre-formed stringer, applying radius fillers to the curved fillet portions of the pre-formed stringer, curing the pre-formed stringer, and removing the forming member from the cured stringer.