Matrix element for tire mould and associated manufacturing method

Patent metadata

Field	Value
Publication number	US-10618237-B2
Application number	US-201615542283-A
Country	US
Kind code	B2
Filing date	Jan 8, 2016
Priority date	Jan 8, 2015
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

The liming element for a tire mould comprises a body 12 delimiting a moulding surface 14 intended to at least partially mould a rolling surface of the tire, at least one injection nozzle 26 arranged on the body and provided with at least one outlet orifice 26a, at least one supply duct extending inside the body and the injection nozzle while being in communication with the said outlet orifice, and at least one shut-off member 30 mobile with respect to the injection nozzle between an outlet orifice closed position and an outlet orifice open position. The body 12, the injection nozzle 26 and the shut-off member 30 are manufactured by the deposition and selective melting of stacked layers of powder.

First claim

The invention claimed is:

1. Liming element for a tire mould comprising a body delimiting a moulding surface configured to at least partially mould a rolling surface of the tire, wherein the lining element further comprises at least one injection nozzle arranged on the body and provided with at least one outlet orifice at least one supply duct extending inside the body and the injection nozzle while being in communication with the said outlet orifice, and at least one shut-off member mobile with respect to the injection nozzle between an outlet orifice closed position and an outlet orifice open position, the body, the injection nozzle and the shut-off member being manufactured by the deposition and selective melting of stacked layers of powder.

2. The lining element according to claim 1 , wherein the injection nozzle is made in one part with the body and projects out with respect to the moulding surface of the said body.

3. The lining element according to claim 1 , wherein the shut-off member is mobile from the closed position to the open position under the effect of the pressure of a fluid or of a solid introduced into the supply duct.

4. The lining element according to claim 1 , wherein the outlet orifice opens onto a frontal surface of the injection nozzle substantially parallel to the moulding surface of the body.

5. The lining element according to claim 1 , wherein the supply duct comprises means of connection to a supply source external to said element.

6. The lining element according to claim 1 , wherein the shut-off member is mobile in translation with respect to the injection nozzle.

7. The lining element according to claim 6 , wherein the shut-off member comprises a piston provided with a rod mounted inside the supply duct and with a shut-off head able to shut off the said outlet orifice in the closed position.

8. The lining element according to claim 1 , wherein the shut-off member is rotationally mobile with respect to the injection nozzle.

9. The lining element according to claim 8 , wherein the shut-off member comprises a flap that comes to bear against a frontal surface of the injection nozzle substantially parallel to the moulding surface of the body in the body closed position.

10. The lining element according to claim 1 , wherein the body comprises venting means extending from the moulding surface and configured to allow air to be evacuated while the tire is being moulded, said venting means being in communication with the supply duct.

11. The lining element according to claim 1 , comprising a plurality of protuberances extending outcuts from the moulding surface of the body and adapted to mould cuts in the tread of the tire.

12. The lining element according to claim 11 , wherein the injection nozzle extends out from a free frontal surface of one of the said protuberances.

13. The lining element according to claim 1 , wherein the injection nozzle extends out from the moulding surface of said body.

14. Mould for a tire of the type comprising a tread and two lateral sidewalls, the mould comprising first and second shells which are adapted to mould the lateral sidewalls of the tire, and a plurality of segments distributed in the circumferential direction and adapted to mould the tread of the said tire, each segment comprising at least one lining element according to claim 1 .

15. Method of manufacturing the lining element according to claim 1 , the lining element comprising a body delimiting a moulding surface adapted to at least partially mould a rolling surface of the tire, comprising the following steps:
a) manufacture, by deposition and selective melting of stacked layers of powder, of the body of the lining element, of at least one injection nozzle arranged on the said body and provided with at least one outlet orifice, and of a shut-off member for shutting off the said outlet orifice, the injection nozzle being rendered as one with the body and the shut-off member being rendered as one with at least the said nozzle during the steps of selective melting of the layers of powder,
b) at least partial formation of at least one supply duct extending inside the body and the injection nozzle and being in communication with the outlet orifice of the said nozzle during the steps of deposition and selective melting of the layers of powder, and
c) partial separation of the shut-off member and of the injection nozzle after the steps of deposition and selective melting of the layers of powder so as to give the shut-off member mobility between positions in which the outlet orifice of the injection nozzle is closed and open.

16. The method according to claim 15 , wherein, according to a modelled melting of the layers of powder, a clearance is provided between part of the shut-off member and a facing part of the injection nozzle, which clearance is comprised between 0.05 and 0.5 mm, so that the deposited powder present between the said facing parts is completely or partially melted by the diffusion of heat locally rendering the shut-off member and the injection nozzle as one.

17. The method according to claim 15 , wherein the shut-off member comprises a piston provided with a rod mounted inside the supply duct and with a shut-off head, and wherein the body of the lining element is manufactured in such a way as to extend in an inclined fashion with respect to a build platform on which a first layer of powder is deposited and melted.

18. Method of moulding a tire according to the mold of claim 14 comprising first and second shells adapted to mould the lateral sidewalls of tire, and a plurality of segments distributed in the circumferential direction and adapted to mould the tread of said tire, in which method the non-vulcanized green tire that is to be moulded is brought into contact with the shells and the segments of the mould, the green tire is heated, and then a fluid or a solid is injected under the exterior surface of the green tire which is in contact with the mould and which is adapted to form the rolling surface of the tire so as to create at least one cavity in the thickness of the green tire and beneath said rolling surface.

Assignees

• Michelin & Cie
• Michelin Rech Tech

Inventors

• Calvel Romain
• Boncompagne Thibault

Classifications

• B29D2030/0614

  porous moulds, e.g. sintered materials · CPC title

• B29D30/0678 Primary

  Injection moulding specially adapted for tyres or parts thereof (injection moulding in general B29C45/00) · CPC title

• B29D30/66

  Moulding treads on to tyre casings, e.g. non-skid treads with spikes · CPC title

• B29D30/0606 Primary

  Vulcanising moulds not integral with vulcanising presses (for solid tyres B29D30/02) · CPC title

• B29D2030/0617

  Venting devices, e.g. vent plugs or inserts · CPC title