CROWN REINFORCEMENT FOR AN AIRCRAFT
Tire for an aeroplane and, in particular, the crown thereof which comprises a tread ( 1 ), a working reinforcement ( 2 ), a carcass reinforcement ( 3 ) and a hoop reinforcement ( 4 ). The radially internal working layer ( 21 ) of the working reinforcement ( 2 ) comprises a concave portion. The hoop reinforcement ( 41 ) comprises at least one hooping layer ( 41 ) radially on the inside of the working layer ( 21 ) and made up of mutually parallel reinforcing elements, having a mean diameter D, that are inclined, with respect to the circumferential direction (XX′), at an angle of between +10° and −10°. The hooping layer ( 41 ) comprises at least one axial discontinuity ( 411 ) having an axial width (L 411 ) at least equal to three times the mean diameter D of the reinforcing elements of the hooping layer ( 41 ).
1 . A tire for an aeroplane, comprising:
a tread;
a working reinforcement radially on the inside of the tread and comprising at least one working layer;
the radially internal working layer having an axial width at least equal to two-thirds of the maximum axial width of the tire and comprising a concave portion;
a carcass reinforcement radially on the inside of the working reinforcement and comprising at least one carcass layer;
a hoop reinforcement radially on the outside of the carcass reinforcement and comprising at least one hooping layer;
the hooping layer having an axial width at most equal to 0.8 times the width of the widest working layer and comprising mutually parallel reinforcing elements that are inclined, with respect to the circumferential direction, at an angle of between +10° and −10°; and
the reinforcing elements of the hooping layer having a mean diameter D,
wherein the hooping layer comprises at least one axial discontinuity having an axial width at least equal to three times the mean diameter D of the reinforcing elements.
2 . The aeroplane tire according to claim 1 , wherein the axial width of the axial discontinuity is at least equal to 10 times the mean diameter D of the reinforcing elements of the hooping layer.
3 . The aeroplane tire according to claim 1 , wherein the hooping layer comprises at least two axial discontinuities having axial widths at least equal to three times the mean diameter D of the reinforcing elements of the hooping layer.
4 . The aeroplane tire according to claim 1 , wherein one said axial discontinuity is centered on the equatorial plane of the tire.
5 . The aeroplane tire according to claim 3 , wherein two said axial discontinuities are positioned symmetrically with respect to the equatorial plane.
6 . The aeroplane tire according to claim 1 , wherein the hoop reinforcement comprises two said hooping layers.
7 . The aeroplane tire according to claim 1 , wherein the reinforcing elements of a said hooping layer consist of aliphatic polyamides, aromatic polyamides or a combination of aliphatic polyamides and aromatic polyamides.
8 . The aeroplane tire according to claim 1 , wherein a said working layer comprises mutually parallel reinforcing elements that are inclined, with respect to the circumferential direction, at an angle of between +20° and −20°.
9 . The aeroplane tire according to claim 1 , wherein wherein the reinforcing elements of a said working layer consist of aliphatic polyamides, aromatic polyamides or a combination of aliphatic polyamides and aromatic polyamides.
10 . The aeroplane tire according to claim 1 , comprising at least one said carcass layer comprising mutually parallel reinforcing elements that form an angle of between 80° and 100° with the circumferential direction, wherein the reinforcing elements of a carcass layer consist of aliphatic polyamides, aromatic polyamides or a combination of aliphatic polyamides and aromatic polyamides.
11 . The aeroplane tire according to claim 1 , wherein a protective reinforcement comprising at least one protective layer made up of metal or textile reinforcing elements is disposed radially on the outside of the working reinforcement.