Tire molding process

Patent metadata

Field	Value
Publication number	US-12391016-B2
Application number	US-202218052243-A
Country	US
Kind code	B2
Filing date	Nov 3, 2022
Priority date	Nov 15, 2021
Publication date	Aug 19, 2025
Grant date	Aug 19, 2025

Abstract

A process for molding a tire within a tire mold having movable elements displaceable to bring the tire mold into an open position or a closed position. The tire mold comprises upper and lower side members; mold segments defining a mold cavity; and one or more seal members for sealing the mold cavity. The process comprises steps of providing a tire mold having one or more closing seal members; placing the green tire into the mold cavity; placing one or more closing seal members next to a cooperating surface so as to face it without contacting it, by bringing the tire mold into a partial closure position; and drawing a vacuum on the mold cavity causing the one or more closing seal members to be moved or deformed by suction until they are in contact with the cooperating surface so that the mold cavity is sealed in an airtight manner.

First claim

What is claimed is:

1. A molding process wherein a green tire is formed and then molded within a tire mold; the tire mold having one or more movable elements that can be displaced to bring the tire mold into an open or into a closed position; the tire mold comprising an actuating ring, a top plate, a bottom plate, upper and lower side members, a plurality of mold segments and slide blocks; the upper and lower side members and the plurality of mold segments defining a mold cavity and the tire mold further comprising sealing means for sealing the mold cavity including one or more closing seal members; wherein the process comprises the following steps:
providing the tire mold having one or more closing seal members;
placing the green tire into the mold cavity;
placing the one or more closing seal members next to a cooperating surface, wherein the one or more closing seal members face the cooperating surface without contacting it, by bringing the tire mold to a partial closure position; and
drawing a vacuum on the mold cavity causing the one or more closing seal members to be moved or deformed by suction until they are in contact with the cooperating surface so that the mold cavity is sealed in an airtight manner,
wherein each of the one or more closing seal members is associated with a cooperating surface, and one of the one or more closing seal members and the cooperating surface being moveable relative to the other during the displacement of the one or more movable elements.

2. The molding process according to claim 1 , wherein in the partial closure position of the tire mold, the one or more closing seal members are spaced from the cooperating surface with a distance of at most 1.5 mm.

3. The molding process according to claim 1 , wherein in the partial closure position of the tire mold, the one or more moveable elements still have a stroke of at least 3.0 mm before the tire mold reaches its closed position.

4. The molding process according to claim 1 , wherein the step of drawing the vacuum on the mold cavity comprises the one or more closing seal members changing from a rest condition where they are spaced from the cooperating surface to a working condition where they are contacting said cooperating surface, and wherein the one or more closing seal members change from their rest condition to their working condition by one or more of deformation and displacement.

5. The molding process according to claim 1 , wherein the mold segments show an inner molding surface with one or more cutting elements; the one or more cutting elements being spaced from the green tire when the tire mold is in its open position and are contacting the green tire to cut its tread portion when the tire mold is in its closed position, and wherein in the partial closure position of the tire mold, the one or more cutting elements are still spaced from the green tire so that the step of drawing the vacuum on the mold cavity is started before the one or more cutting elements come into contact with the green tire.

6. The molding process according to claim 1 , wherein the actuating ring is one of the one or more moveable elements and can be displaced from an initial position to a final position to close the tire mold, and wherein the step of drawing the vacuum in the mold cavity is started before the actuating ring reaches its final position.

7. The molding process according to claim 1 , wherein the one or more closing seal members comprise an upper closing seal member that is placed on the top plate and the associated cooperating surface is an essentially vertical edge of the actuating ring or an essentially vertical edge of an upper seal plate fixed to the actuating ring.

8. The molding process according to claim 7 , wherein the upper closing seal member is an O-ring seal member and is arranged in one of i) a groove of an essentially vertical wall of the top plate and ii) a recess of an essentially vertical wall of the top plate and maintained in position by a hook.

9. The molding process according to claim 7 , wherein the upper closing seal member is a T-seal member anchored in a groove of an upper surface of the top plate and extending essentially vertically so that the cooperating surface faces an essentially vertical side of the T-seal member.

10. The molding process according to claim 1 , wherein the one or more closing seal members comprise a lower seal member placed on the actuating ring, wherein the lower closing seal member is an O-ring seal member arranged in a groove of an essentially vertical wall of the actuating ring, and the cooperating surface is an essentially vertically extending ledge arranged at the outer end of the bottom plate.

11. The molding process according to claim 1 , wherein the one or more closing seal members comprise a lower seal member which is a T-seal member anchored to the bottom plate or to the actuating ring and is extending essentially vertically so that the cooperating surface faces a vertical side of the T-seal member, the cooperating surface being on the actuating ring or the bottom plate respectively.

12. A molding process wherein a green tire having a tread, sidewall and bead portions is formed and then molded within a tire mold; the tire mold having one or more movable elements that can be displaced to bring the tire mold into an open or a closed position; the tire mold comprising an actuating ring, a top plate, a bottom plate, upper and lower side members, a plurality of mold segments and slide blocks, and a vacuum device; the upper and lower side members and the plurality of mold segments defining a mold cavity, and the tire mold further comprising sealing means for sealing the mold cavity including one or more closing seal members; wherein the process comprises the following steps:
providing the tire mold having one or more closing seal members placed on one or more carrier elements wherein each of the one or more closing seal members is associated with a cooperating surface, and one of the one or more closing seal members and the cooperating surface being moveable relative to the other during a stroke of the one or more moveable elements between the open position and the closed position of the tire mold;
opening the tire mold and placing the green tire into the mold cavity;
placing the one or more closing seal members next to the respective cooperating surface so as to face it without contacting it by bringing the tire mold to a partial closure position, wherein the one or more closing seal members are in a rest condition and spaced from the cooperating surface with a distance of at most 1.5 mm; and
drawing a vacuum on the mold cavity allowing the one or more closing seal members to change from their rest condition to a working condition in which they are in contact with their associated cooperating surface.

13. The molding process according to claim 12 , wherein the vacuum device is activated to draw the vacuum in the tire mold for a time ranging from 5 to 40 seconds.

14. The molding process according to claim 12 , further comprising the steps of:
closing the tire mold while the vacuum is drawn and curing the tire, wherein a vacuum device for drawing the vacuum is deactivated during the step of curing causing the one or more closing seal members to change from their working condition back to their rest condition.

15. The molding process according to claim 12 , wherein the one or more closing seal members are made of an elastic material.

16. A molding process wherein a green tire having a tread, sidewall and bead portions is formed and then molded within a tire mold; the tire mold having

Assignees

• Goodyear Tire & Rubber

Inventors

• Pierre Christophe Jean Alexis Ghislain
• Windehausen Michel Jean Yves

Classifications

• B29D2030/0607

  Constructional features of the moulds · CPC title

• B29C2791/006

  Using vacuum · CPC title

• B29C33/0038

  with sealing means or the like (seals on envelopes used in tyre retreading B29D30/542; for injection moulding footwear B29D35/0045) · CPC title

• B29C33/10

  with incorporated venting means · CPC title

• B29D30/0629

  with radially movable sectors · CPC title