Anti-lightning strike fasteners for composite material aircraft structures
US4891732A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1987 |
| Grant date | Jan 2, 1990 |
| Priority date | — |
| Expiry date | Nov 30, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB64D45/02
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A fastener for use with aircraft structures comprising composite materials has improved electrical characteristics designed to reduce damage by lightning strikes. The fastener comprises separate nut and bolt portions and a cage member (4, 1, 6). The nut (4) and the head portion of the bolt 1 both have beveled edges which in use are countersunk in the composite materials to enhance electrical contact between the fastener and aircraft structural members (2, 5). The nut (4) is captively mounted inside the cage member (6) and is moveable, within pre-determined limits, inside the cage (6) so that it may be axially aligned with and the bolt screwed therein, thus compensating for any initial non-aligment of the nut (4) and bolt (1) due to a complex shape of the aircraft structure necessitated by aerodynamic or other considerations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.