Extended mobility tire with undulating sidewalls

• US 7,281,557 B2
• Filed: 05/18/2005
• Issued: 10/16/2007
• Est. Priority Date: 11/18/2002
• Status: Expired due to Fees

• Current Assignee: Michelin Recherche et Technique SA (Compagnie Generale DES Etablissements Michelin SCA)
• Original Assignee: Michelin Recherche et Technique SA (Compagnie Generale DES Etablissements Michelin SCA)
• Inventors: Merino Lopez, Jose
• Primary Examiner(s): Johnstone; Adrienne C.
• Application Number:
  US11/131,318
• Publication Number:
  US 20050263230A1
• Time in Patent Office: 881 Days
• Field of Search: 152/454, 152/457, 152/516, 152/522, 152/523, 152/555, 152/556, 152/557, 152/550
• US Class Current: 152/454
• CPC Class Codes: B60C 9/09 combined with other carcass plies having cords extending diagonally from bead to bead, i.e. combined radial ply and bias angle ply
• CPC Class Codes: Y10T 152/10864 Sidewall stiffening or reinforcing means other than main carcass plies or foldups thereof about beads

Abstract

A tire includes at least one carcass-type reinforcement structure anchored on each side in a bead, each bead being extended radially towards the outside by a sidewall having at least one substantially resilient circumferential cord disposed in the substantially median portion of the sidewalls. The carcass-type reinforcement structure includes a ply of carcass cords extending from the bead to the crown within a sidewall. The carcass cords are arranged in such a way that, in a sidewall zone restricted to the median portion of the sidewall, the carcass cords exhibit different respective axial positions, so as to form around the circumference a succession of substantially regular undulations defining an undulating circumferential profile. Outside of the sidewall zone, the carcass cords of the ply do not form undulations. At reduced pressure the undulations tend to straighten out and rigidify the sidewall in such a way as to be able to bear the load.

Claims

1. A tire comprising a reinforced crown, at least one carcass-type reinforcement structure extending circumferentially and anchored on each side of the tire in a bead whose base is intended to be fitted on a rim seat, each bead extended radially towards the outside by a sidewall, the sidewall meeting up radially towards the outside with a tread and comprising at least one substantially resilient circumferential cord disposed in the substantially median portion of said sidewall, each of the beads comprising furthermore an anchoring zone in which the carcass-type reinforcement structure is retained, said carcass-type reinforcement structure including a ply of carcass cords wherein a portion of each carcass cord is disposed in a sidewall and extends from a respective bead to the crown, the carcass cords arranged in such a way that, on the one hand, in a substantially median zone of the sidewall, the immediately adjacent carcass cords of said ply exhibit different respective axial positions over the circumference, so as to form in the sidewall zone a succession of substantially regular undulations forming an undulating circumferential profile, and on the other hand, outside the sidewall zone, all cords of said ply exhibit substantially identical respective axial positions, the sidewall zone having a radially outer border spaced radially inwardly from the crown and a radially inner border spaced radially outwardly from the respective bead.

2. The tire of claim 1, wherein in said sidewall zone, the carcass-type reinforcement structure is located between a first reinforcement structure path axially furthest to the inside and a second reinforcement structure path axially furthest to the outside.

3. The tire of claim 1, in which the outer surface of said sidewall of the tire, in the sidewall zone where the reinforcement structure comprises said undulations, also exhibits an undulating circumferential profile, substantially congruent with said undulating profile formed by said reinforcement structure.

4. The tire of claim 1, in which the radial position of a reinforcement cord, for a given circumferential position of the undulating circumferential profile, is substantially symmetrical in each sidewall relative to the median plane of said tire.

5. The tire of claim 1, in which the radial position of a reinforcement cord, for a given circumferential position of the undulating circumferential profile, is substantially opposing in each sidewall.