Closing member for opening
An object of the invention is to provide a low-cost closing member for an opening having an excellent lightning protection capability. A door body 30 , a clamp ring 40 made of a composite material, and an opening 12 of a wing panel 11 made of the composite material are electrically connected by surface bonding of conductive materials in a butt section of an abutment surface 34 of the door body 30 and a tapered surface 40 c of the clamp ring 40 and a butt section of a tapered surface 40 d of the clamp ring 40 and an abutment surface 14 of the opening 12.
1. A closing member for an opening that is formed in a panel constituting an outer surface of an airframe of an aircraft and being made of a composite material including a carbon fiber, the closing member comprising:
a closing member body configured to be disposed on one surface side of the panel to close the opening such that at least a side thereof faces and is exposed to an exterior of the airframe, the closing member body being made of one of titanium alloy, a stainless alloy, and a composite material including a carbon fiber, the closing member body having an external diameter larger than that of the opening;
a ring-shaped clamp member configured to be disposed on the other surface side of the panel such that at least a surface side of the clamp member faces an exterior of the airframe, the clamp member being made of the composite material including the carbon fiber, the clamp member having an external diameter larger than that of the opening; and
a fastener configured to tighten the closing member body and the clamp member while the panel is held between an outer circumferential portion of the closing member body and an outer circumferential portion of the clamp member,
wherein the closing member body and the clamp member are configured to be disposed such that the closing member body and an inner circumferential portion of the clamp member abut on each other, and the outer circumferential portion of the clamp member and an inner edge portion of the opening abut on each other, whereby the closing member is electrically connected to the panel through the clamp member.
2. The closing member for an opening according to claim 1 , wherein an abutment surface of the closing member body and the inner circumferential portion of the clamp member and an abutment surface of the outer circumferential portion of the clamp member and the inner edge portion of the opening constitute a tapered surface that is configured to be tilted with respect to a direction orthogonal to the airframe surface when the clamp member and the closing member body are disposed.
3. The closing member for an opening according to claim 1 , wherein, in the clamp member, the surface that is to be located on the outward of the airframe is made of the composite material including the carbon fiber while a surface facing an inward of the airframe is made of a metallic material.
4. The closing member for an opening according to claim 3 , wherein the metallic material is an aluminum alloy.
5. The closing member for an opening according to claim 3 , wherein the clamp member comprises a first layer made of the composite material, a second layer made of the metallic material, and an insulating layer provided between the first layer and the second layer.
6. The closing member for an opening according to claim 5 , wherein the first layer and the second layer are integrally joined by an adhesive agent.
7. An aircraft comprising the closing member according to claim 1 .
8. The aircraft according to claim 7 , wherein the opening is provided in a main wing constituting the airframe, and the opening is an access to a fuel tank accommodated in the main wing.