Aircraft cover including means for limiting the scoop phenomena of pneumatic type
An aircraft nacelle includes at its outside wall a cowl moveable relative to the nacelle so as to block or unblock an opening. The cowl includes an articulation and locking/unlocking elements distant from the upstream edge of the cowl that include elements for limiting the appearance of scooping phenomena. The limiting elements include at least one lock integral with the rest of the nacelle or respectively the cowl that can occupy a locked state in which part of the lock interferes with the cowl or respectively the rest of the nacelle and prevents a deformation that includes a radial component of the cowl, and another free state in which the part no longer interferes with the cowl or respectively the rest of the nacelle and allows the opening movement of the cowl, with the switch from one state to the next being generated by a gas pressure variation.
1. An aircraft nacelle ( 10 ) having an outside wall with a cowl ( 14 ) that moves relative to the rest of the nacelle ( 10 ) in such a way as to block or unblock an opening, said cowl ( 14 ) comprising:
an articulation ( 15 ) relative to the rest of the nacelle ( 10 ) and a latch ( 17 ) opposite the articulation for holding said cowl ( 14 ); and
means ( 19 ) for limiting the appearance of scooping phenomena, said means ( 19 ) for limiting the appearance of the scooping phenomenon comprising at least one lock ( 26 ) that is integral with the rest of the nacelle ( 10 ) or respectively the cowl ( 14 ) and that occupies a locked state in which a part of the lock ( 26 ) interferes with the cowl ( 14 ) or respectively the rest of the nacelle ( 10 ) and prevents a deformation that comprises a radial component of said cowl ( 14 ) and a free state in which said part of the lock ( 26 ) no longer interferes with the cowl ( 14 ) or respectively the rest of the nacelle ( 10 ) and allows the opening movement of said cowl ( 14 ),
wherein the at least one lock comprises a membrane arranged to receive a gas so as to switch the at least one lock between the locked and free states by a pressure variation of the gas.
2. The aircraft nacelle according to claim 1 , wherein the membrane ( 44 ) is upstream from the opening and is arranged to move in response to the pressure variation of the gas and to expand into and withdraw from a first groove ( 60 ) that is upstream from the cowl ( 14 ) and open toward a front of the nacelle ( 10 ) so as to switch the at least one lock between the locked and free states.
3. The aircraft nacelle according to claim 2 , further comprising a second groove ( 62 ) opposite the first groove ( 60 ) and that receives the membrane.
4. The aircraft nacelle according to claim 1 , wherein the at least one lock ( 26 ) comprises a rod ( 28 ) that is guided in translation in a direction that is contained in a longitudinal plane and that makes an angle that is greater than 60° relative to the radial direction.
5. The aircraft nacelle according to claim 4 , wherein the membrane ( 44 ) expands and contracts by operation of the pressure variation of the gas to move the rod ( 28 ), the rod being movable in an opening ( 36 ) in a wall ( 38 ) that is integral with the cowl ( 14 ).
6. The aircraft nacelle according to claim 5 , wherein the membrane ( 44 ) is a bellows comprising an elastic material.
7. The aircraft nacelle according to claim 1 , the at least one lock comprising a spring ( 42 ) for placing the lock ( 26 ) in the free state, wherein the membrane expands against the spring by operation of the pressure variation of the gas to place the lock ( 26 ) in the locked state.
8. The aircraft nacelle according to claim 7 , further comprising a tap ( 46 ) at an outside surface of the nacelle and that is connected to the membrane to supply the gas.
9. The aircraft nacelle according to claim 7 , further comprising a tap ( 46 ′) inside the nacelle and connected to the membrane to supply the gas.
10. The aircraft nacelle according to claim 7 , further comprising a tap ( 46 ′) at a pressurized duct of a power plant and connected to the membrane to supply the gas.