Method for manufacturing a structure with cellular cores for a turbojet nacelle

Abstract

The invention relates to a method for manufacturing a structure with cellular cores ( 202 ) that can be used in the structural panel of a turbojet nacelle, including at least one block of cellular cores (A, B) having a central portion ( 5 a, 5 b ) with core honeycomb cells ( 7 a, 7 b ) and at least two side portions ( 9 a, 9 a′, 9 b, 9 b ′) each including side honeycomb cells ( 11 a, 11 b ), wherein said method includes the following steps: A) forming junction walls on the side honeycomb cells ( 11 a, 11 b ), the junction walls being capable of interacting for forming a junction area ( 213 ); B) unfolding the junction walls thus formed; and C) joining the walls thus unfolded ( 46 ) and belonging to two different side portions ( 9 a, 9 b) end-to-end so that said junction walls ( 46 ) are fitted together so as to form a junction area ( 213 ). The invention also relates to a structural panel and to a nacelle including a structure with cellular cores obtained by said method.

1 . A method for manufacturing a structure with cellular cores that can be used in a structural panel of a turbojet nacelle, including at least one block of cellular cores having a central portion with core honeycomb cells and at least two side portions each including side honeycomb cells, wherein said method comprises:
 A) forming junction walls on the side honeycomb cells, the junction walls being capable of interacting for forming a junction area;   B) unfolding the junction walls thus formed; and   C) joining the walls thus unfolded and belonging to two different side portions end-to-end so that said junction walls are fitted together so as to form a junction area.   
     
     
         2 . The method according to the preceding- claim 1 , wherein a length of each junction wall is greater than or equal to a largest length of the side and/or core honeycomb cells. 
     
     
         3 . The method according to  claim 1 , wherein the side parts belonging to cellular core blocks, whereof the side and core honeycomb cells have different sizes, are joined end-to-end. 
     
     
         4 . The method according to  claim 1 , wherein, in step A, one opens the edge honeycomb cells situated on edges of a side part of a block intended to be joined and honeycomb cells adjacent to the edge honeycomb cells so as to form the junction walls. 
     
     
         5 . The method according to  claim 4 , wherein the edge and adjacent honeycomb cells are opened by section to a lateral side and/or a wall of a honeycomb cell. 
     
     
         6 . The method according to  claim 1 , comprising an additional step D in which the fitting done in step C is maintained by clamps or staples. 
     
     
         7 . A structural panel for a nacelle surrounding a turbojet engine, comprising at least one cellular core structure obtained using the method according to  claim 1 . 
     
     
         8 . The panel according to  claim 7  being an acoustic panel whereof the cellular core structure(s) are coated on one faces thereof with an outer skin impermeable to air and on their-another face with an air-permeable perforated inner skin. 
     
     
         9 . The panel according to  claim 7 , having at least two cellular core structures superimposed one on the other. 
     
     
         10 . An aircraft engine nacelle, comprising at least one structural panel according to  claim 7 . 
     
     
         11 . The nacelle according to the preceding claim, wherein the structural panel(s) are situated in an air intake zone of said nacelle.