Crown reinforcement for an aircraft tire

Patent metadata

Field	Value
Publication number	US-10589573-B2
Application number	US-201415036608-A
Country	US
Kind code	B2
Filing date	Nov 6, 2014
Priority date	Nov 15, 2013
Publication date	Mar 17, 2020
Grant date	Mar 17, 2020

Abstract

Crown reinforcement of an aircraft tire comprises a working reinforcement (2) radially inside of tread (3) and radially outside of carcass reinforcement (4). Working reinforcement (2) comprises two working bi-plies (21, 22) radially superposed with respective axial widths (L1, L2), from first axial end (I1, I2) to second axial end (I′1, I′2). Each working bi-ply (21, 22) comprises two working layers (211, 212; 221, 222) radially superposed and respectively made up of axially juxtaposed portions of strip (5) of axial width W extending circumferentially in periodic curve (6) that forms, in the equatorial plane (XZ) of the tire and with the circumferential direction (XX′) of the tire, a non-zero angle A and has a radius of curvature R at its extrema (7). The difference DL between the respective axial widths (L1, L2) of the radially superposed working bi-plies (21, 22) is at least equal to 2×(W+(R−W/2)−(1−cos A)).

First claim

The invention claimed is:

1. An aircraft tire comprising:
a working reinforcement radially on an inside of a tread and radially on an outside of a carcass reinforcement;
the working reinforcement comprising at least two working bi-plies which are radially superposed and respectively have an axial width, from a first axial end to a second axial end;
each said working bi-ply having a main section comprising at least in part two working layers that are radially superposed, a first, radially outer, one of the at least two working bi-plies comprising, at an axial end thereof, a first axial-end additional thickness, extending axially to an outside of the main section of the first bi-ply, the first axial-end additional thickness comprising a first set of two additional working layers sandwiched between the two working layers of the first bi-ply such that the first axial-end additional thickness is four superposed working layers, each working layer being respectively made up of an axial juxtaposition of portions of a strip, and a second, radially inner, one of the two working bi-plies comprising, at an axial end thereof, a second axial-end additional thickness, extending axially to an outside of the main section of the second bi-ply, the second axial-end additional thickness comprising a second set of two additional working layers sandwiched between the two working layers of the second bi-ply,
wherein the working reinforcement comprises six working layers only in a region of axial overlap between the first axial-end additional thickness and the main section of the second, radially inner, bi-ply;
the strip, of axial width W, extending circumferentially in a periodic curve that forms, in the equatorial plane of the tire and with the circumferential direction of the tire, a non-zero angle A and has a radius of curvature R at its extrema;
the strip being made up of reinforcers coated in an elastomeric compound;
wherein a difference DL between the respective axial widths of the at least two radially superposed working bi-plies is at least equal to 2×(W+(R−W/2)×(1−cos A)),
wherein the first, radially outer, one of the at least two working bi-plies contacts the second, radially inner, one of the at least two working bi-plies, over their respective axial widths axially inwardly of the first axial-end additional thickness, and the first and second axial-end additional thicknesses are axially offset by a distance of DL/2.

2. The aircraft tire according to claim 1 , wherein the axial width W of the strip is at least equal to 2 mm.

3. The aircraft tire according to claim 1 , wherein the axial width W of the strip is at most equal to 20 mm.

4. The aircraft tire according to claim 1 , wherein a ratio R/W between the radius of curvature R, at the extrema of the periodic curve of the strip, and the width W of the strip is at least equal to 13.

5. The aircraft tire according to claim 1 , wherein the non-zero angle A formed by the periodic curve of the strip in the equatorial plane and with the circumferential direction is at least equal to 3°.

6. The aircraft tire according to claim 1 , wherein the non-zero angle A, formed by the periodic curve of the strip in the equatorial plane and with the circumferential direction is at most equal to 35°.

7. The aircraft tire according to claim 1 , wherein the reinforcers of the strip are made of a textile material.

8. The aircraft tire according to claim 1 , wherein the reinforcers of the strip are made of an aliphatic polyamide.

9. The aircraft tire according to claim 1 , wherein the reinforcers of the strip are made of an aromatic polyamide.

10. The aircraft tire according to claim 1 , wherein the reinforcers of the strip are made of a combination of an aliphatic polyamide and of an aromatic polyamide.

11. Method of manufacturing an aircraft tire according to claim 1 , comprising a step of manufacturing the working reinforcement, wherein the at least two working bi-plies that are radially superposed and respectively have an axial width, from a first axial end to a second axial end, are obtained by circumferential zigzag winding of the strip, of axial width W, on the lateral surface of a tire building drum of radius R f and having as its axis the axis of rotation of the tire, with the periodic curve forming, in the equatorial plane and with the circumferential direction, the non-zero angle A and having the radius of curvature R at its said extrema such that the difference DL between the respective axial widths of the at least two radially superposed working bi-plies is at least equal, in terms of absolute value, to 2×(W+(R−W/2)×(1−cos A)).

12. The aircraft tire according to claim 1 , wherein the axial width W of the strip is at least equal to 6 mm.

13. The aircraft tire according to claim 1 , wherein the axial width W of the strip is at most equal to 14 mm.

14. The aircraft tire according to claim 1 , wherein the non-zero angle A formed by the periodic curve of the strip in the equatorial plane and with the circumferential direction is at least equal to 5°.

15. The aircraft tire according to claim 1 , wherein the non-zero angle A, formed by the periodic curve of the strip in the equatorial plane and with the circumferential direction is at most equal to 25°.

Assignees

• Michelin & Cie
• Michelin Rech Tech

Inventors

• Romero De La Osa Marc
• Delacroix Serge

Classifications

• B60C2200/02

  for aircrafts · CPC title

• B60C2009/2035

  built-up by narrow strips · CPC title

• B29K2713/02

  coated · CPC title

• B29D30/22

  Breaker plies being applied in the unexpanded state · CPC title

• B60C2009/2016

  comprising cords at an angle of 10 to 30 degrees to the circumferential direction · CPC title