METHOD FOR MANUFACTURING AN IMPROVED PNEUMATIC TIRE

• US 20200130309A1
• Filed: 07/02/2018
• Published: 04/30/2020
• Est. Priority Date: 07/11/2017
• Status: Active Grant

• Current Assignee: Compagnie Generale DES Etablissements Michelin SCA
• Original Assignee: Compagnie Generale DES Etablissements Michelin SCA
• Inventors: PIALOT, Frederic, FABRE, Thomas, WIEL, Pierre
• Granted Patent: US 11,602,913 B2
• Time in Patent Office: Days
• CPC Class Codes: B29C 45/1459 Coating annular articles
• CPC Class Codes: B29C 45/1671 with an insert
• CPC Class Codes: B29D 30/0678 Injection moulding specially adapted for tyres or parts thereof injection moulding in general B29C45/00
• CPC Class Codes: B29D 30/52 Unvulcanised treads, e.g. on used tyres; Retreading apparatus for forming treads by extrusion B29C48/00; apparatus for vulcanising treads B29C35/02; apparatus characterised by the means for holding wheels or parts thereof B60B30/00
• CPC Class Codes: B29D 30/66 Moulding treads on to tyre casings, e.g. non-skid treads with spikes
• CPC Class Codes: B29K 2021/003 Thermoplastic elastomers
• CPC Class Codes: B29L 2030/002 Treads
• CPC Class Codes: B29L 2030/003 Plies; Breakers
• CPC Class Codes: B29L 2030/007 Sidewalls

Abstract

The invention relates to a process for manufacturing a tire (1). The process includes the steps a): forming a carcass (3) from at least one first material based on thermoplastic elastomer, b): forming, on the carcass (3), at least bead zones (10) from at least one second material based on thermoplastic elastomer and c): forming, on the assembly obtained during step b), an additional part from at least one third material based on thermoplastic elastomer.

Claims

1. A process for manufacturing a tire, comprising the following steps:

a) forming a carcass from at least one first material based on thermoplastic elastomer;

b) forming on the carcass at least bead zones from at least one second material based on thermoplastic elastomer;

c) forming, on the assembly obtained during step b), an additional part from at least one third material based on thermoplastic elastomer in order to obtain a tire which comprises a tread formed during step b) or step c) from a material based on thermoplastic elastomer.

2. The process according to claim 1, in which step a) includes the following phases:

a1) manufacturing a carcass ply and two bead wires;

a2) injecting, into a carcass mold, the first material based on thermoplastic elastomer while overmolding this first material around the carcass ply and the two bead wires so as to form the carcass;

a3) cooling, in the carcass mold, the assembly obtained during step a2);

a4) releasing the carcass thus formed from the carcass mold.

3. The process according to claim 1, in which step b) includes the following phases:

b1) manufacturing at least one reinforcing ply;

b2) injecting, into a bead zone mold, the second material based on thermoplastic elastomer while overmolding this second material on the reinforcing ply so as to form the bead zones and a tread on the carcass;

b3) cooling, in the bead zone mold, the assembly obtained during step b2);

b4) releasing the assembly obtained during step b2) from the bead zone mold.

4. The process according to claim 1, in which step c) includes the following phases:

c1) injecting, into an additional part mold, the third material based on thermoplastic elastomer so as to form exterior sidewalls;

c2) cooling, in the additional part mold, the assembly obtained during step c1);

c3) releasing the tire (1) thus formed from the additional part mold.

5. The process according to claim 1, in which step b) includes the following phases:

b5) injecting, into a bead zone mold, the second material based on thermoplastic elastomer so as to form the bead zones on the carcass;

mold b7) releasing the assembly obtained during step b5) from the bead zone mold.

6. The process according to claim 1, in which step c) includes the following phases:

c4) manufacturing at least one reinforcing ply;

c5) injecting, into an additional part mold, the third material based on thermoplastic elastomer while overmolding this third material on the reinforcing ply so as to form exterior sidewalls and a tread;

c6) cooling, in the additional part mold, the assembly obtained during step c5);

c7) releasing the tire (1) thus formed from the additional part mould.

7. The process according to claim 1, in which step b) includes the following phases:

b8) injecting, into a bead zone mold, the second material based on thermoplastic elastomer so as to form the bead zones and exterior sidewalls on the carcass;

b9) cooling, in the bead zone mold, the assembly obtained during step b8);

b10) releasing the assembly obtained during step b8) from the bead zone mold.

8. The process according to claim 1, in which step c) includes the following phases:

c4) manufacturing at least one reinforcing ply;

c8) injecting, into an additional part mold, the third material based on thermoplastic elastomer while overmolding this third material on the reinforcing ply so as to form a tread;

c9) cooling, in the additional part mold, the assembly obtained during step c8);

c10) releasing the tire (1) thus formed from the additional part mold.

9. The process according to claim 2, in which each mold is formed from a frame arranged to receive removable elements dedicated to each step a), b) and c).

10. The process according to claim 2, in which each mold is maintained at a temperature below 35°

C. during the implementation of the process.

11. The process according to claim 2, in which each cooling phase allows the rigidification of at least the outer surface of the material used based on thermoplastic elastomer by cooling it below a given temperature which is a function of the material used based on thermoplastic elastomer.

12. The process according to claim 1, in which the given temperature is the glass transition temperature or the melting point of the material used based on thermoplastic elastomer.