Honeycomb core structure for use in a structural panel for a jet engine nacelle
The invention relates to a honeycomb core structure ( 202 ) for use in a structural panel for a jet engine nacelle, comprising at least one block with a honeycomb core (A, B) having a central part ( 5 a, 5 b ) with core honeycomb cells ( 7 a, 7 b ) and at least two lateral parts ( 9 a, 9 b ) each comprising a number of honeycomb joining cells ( 11 a, 11 b ) of which at least one part of the honeycomb joining cells ( 11 a , 11 b ) has at least one additional wall ( 201 a, 201 b ) to form a join, the honeycomb core block(s) (A, B) being connected by at least one joint zone ( 213 ) formed by punching two additional walls ( 201 a, 201 b ) superimposed one or the other and provided by honeycomb joining cells ( 11 a, 11 b ) belonging to the distinct lateral parts ( 9 a, 9 b ). The invention further relates to a structural panel and a nacelle comprising such a structure ( 202 ) and a method for producing such a structure ( 202 ).
1. A honeycomb core structure for use in a structural panel for a jet engine nacelle, comprising:
at least one honeycomb core block with a honeycomb core having a central part with core honeycomb cells; and
at least two lateral parts each comprising a number of honeycomb joining cells of which, maintaining a closed cell form, at least one part of the honeycomb joining cells has at least one additional wall to form a join,
wherein the honeycomb core block(s) are rigidly connected by at least one joint zone formed by two additional walls superimposed and punched on each other, and provided by the honeycomb joining cells belonging to distinct lateral parts.
2. The structure according to claim 1 , wherein the two additional walls are unfolded.
3. The structure according to claim 1 , wherein a length of the two additional walls is larger than a diameter of a punching and smaller than or equal to a length of a side of a honeycomb cell of the honeycomb core.
4. The structure according to claim 1 , wherein the honeycomb joining and core cells are made from metal, an alloy, or a composite material.
5. The structure according to claim 1 , further comprising a plurality of blocks with a honeycomb core defining a plurality of joint zones.
6. The structure according to claim 1 , wherein the structure is single-layered and comprises another block joined on said at least one honeycomb core block.
7. A structural panel for a turbojet engine nacelle, comprising at least one honeycomb core structure according to claim 1 .
8. The panel according to claim 7 , wherein the panel comprises an acoustic panel.
9. A jet engine nacelle comprising a structural panel according to claim 7 .
10. A method for making a honeycomb core structure according to claim 1 , comprising:
A—forming at least one additional wall on lateral honeycomb cells of at least one block with a honeycomb core defining two lateral parts surrounding a central part;
B—at least partially superimposing the additional walls on the honeycomb joining cells belonging to two separate lateral parts;
C—joining the honeycomb core block(s) by punching the additional walls thus superimposing via a punching means to form the honeycomb core structure.
11. The method according to claim 10 , wherein, in step A, the additional wall(s) are formed by cutting, substantially crosswise, a block with a honeycomb core whereof the honeycomb cells are expanded.
12. The method according to claim 10 , wherein, in step B, the additional walls are superimposed when the honeycomb joining and/or core ( 7 a , 7 b ) cells are not expanded.
13. The method according to claim 10 , wherein, in step C, the punching means is eyeletting pliers.