Composite airfoil structures and their forming methods

Patent 6234423 Issued on May 22, 2001. Estimated Expiration Date:

July 29, 2019. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3768760

3775238

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Inventors

Assignee

Japan Aircraft Development Corporation

Application

No. 363396 filed on 07/29/1999

US Classes:

244/133, Materials of construction416/226, Formed with main spar416/230Wire, fiber, strand or fabric

Examiners

Primary: Barefoot, Galen L.

Attorney, Agent or Firm

Smith, Gambrell & Russell, LLP

International Class

B64C 003/20

Foreign Application Priority Data

1998-07-30 JP

Abstract

A box-structure airfoil is constructed of a composite material upper skin, a composite material lower skin 12 and a spar. Ribs and an elongate projection are formed integrally on the inner surface of each of the two skins. The upper and lower skins and the spar are simultaneously bonded by an adhesive to form a single structure. Since the ribs and the elongate projection are one-piece formed with each skin, it is possible to reduce the number of principal constituent components. Furthermore, since assembly operation is made by using the adhesive, there is no need for fasteners or the like for assembling. Moreover, the spar is bonded not only to Moreover, because not only a web but also flanges on both sides of the spar are bonded to the respective skins, it is possible to obtain a large strength. According to the invention, it is possible to reduce the number of principal constituent components and that of assembling components of an airfoil, thereby achieving its cost reduction.