Use of a moisture reservoir for retreading

Patent metadata

Field	Value
Publication number	US-12358250-B2
Application number	US-202117914017-A
Country	US
Kind code	B2
Filing date	Mar 10, 2021
Priority date	Mar 26, 2020
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A method of retreading a tire. The method includes the steps of applying a primer to an inner surface of a circumferential tread and applying the primer to an outer surface of a tire casing; applying an adhesive to the primer disposed on the inner surface and the primer disposed on the outer surface; applying the circumferential tread to the tire casing so the inner surface contacts the outer surface and a bondline edge forms circumferentially about the tire casing proximate to a shoulder area of the tire casing; and coupling a moisture reservoir to the circumferential tread proximate to the bondline edge.

First claim

What is claimed is:

1. A method of retreading a tire without the use of a curing chamber for vulcanizing rubber, the method comprising:
determining a predetermined amount of moisture associated with controlling a release of water vapor during curing of a moisture-curing adhesive;
interposing a moisture-curing adhesive between an inner surface of a circumferential tread and an outer surface of a tire casing;
applying the circumferential tread to the tire casing so the inner surface contacts the outer surface and a bondline edge forms circumferentially about the tire casing proximate to a shoulder of the tire casing;
coupling a moisture reservoir to the circumferential tread proximate to the bondline edge such that at least a portion of the circumferential tread is not covered by the moisture reservoir;
interposing a film between the bondline edge and the moisture reservoir such that the film prevents interfacing between the bondline edge and the moisture reservoir;
wetting the moisture reservoir with the predetermined amount of moisture such that, responsive to the wetting, the water vapor is released from the moisture reservoir and permeates the bondline edge;
enclosing the circumferential tread, the tire casing, and the moisture reservoir within an envelope, the envelope being positioned so as to extend within grooves of the circumferential tread; and
removing air from the envelope to apply a pressure to the circumferential tread in a direction toward the tire casing such that an additional amount of moisture is released from the moisture reservoir and directed to the bondline edge to permeate the bondline edge,
wherein the envelope is positioned within the grooves to reduce moisture circulation within the envelope, and
wherein the film is coupled to the portion of the circumferential tread that is not covered by the moisture reservoir such that the envelope comes into contact with the film when air is removed from the envelope.

2. The method of claim 1 , further comprising:
forming a precured tread strip having a generally planar mounting surface and a ground-contacting opposing surface opposite and parallel to the generally planar mounting surface; and
vulcanizing two ends of the precured tread strip together to form the circumferential tread.

3. A method of retreading a tire without the use of a curing chamber for vulcanizing rubber, the method comprising:
determining a predetermined amount of moisture associated with controlling a release of water vapor during curing of an adhesive within an envelope;
applying a primer to an inner surface of a circumferential tread and applying the primer to an outer surface of a tire casing;
applying an adhesive to the primer disposed on at least one of the inner surface and the outer surface;
applying the circumferential tread to the tire casing;
coupling a moisture reservoir to the circumferential tread such that at least a portion of the circumferential tread is not covered by the moisture reservoir;
interposing a film between the bondline edge and the moisture reservoir such that the film prevents interfacing between the bondline edge and the moisture reservoir;
wetting the moisture reservoir with the predetermined amount of moisture such that, responsive to the wetting, the water vapor is released from the moisture reservoir;
enclosing the tire casing, the circumferential tread, and the moisture reservoir in the envelope, the envelope being positioned so as to extend within grooves of the circumferential tread; and
removing air from the envelope to apply a pressure to the circumferential tread in a direction toward the tire casing such that an additional amount of moisture is released from the moisture reservoir and directed to the bondline edge to permeate the bondline edge,
wherein the envelope is positioned within the grooves to reduce moisture circulation within the envelope, and
wherein the film is coupled to the portion of the circumferential tread that is not covered by the moisture reservoir such that the envelope comes into contact with the film when air is removed from the envelope.

4. The method of claim 3 , further comprising:
curing the adhesive at a temperature of 40-130 degrees Fahrenheit, inclusive.

5. The method of claim 4 , further comprising:
curing the adhesive for 24 hours.

6. The method of claim 4 , further comprising:
applying a pressure of 40-100 PSI to the circumferential tread as the adhesive is curing.

7. The method of claim 3 , further comprising, prior to applying the circumferential tread to the tire casing, misting the adhesive with an adhesive reactant.

8. The method of claim 3 , wherein coupling the moisture reservoir to the circumferential tread further comprises covering the entirety of the circumferential tread with the moisture reservoir such that the moisture reservoir is interposed between the envelope and the circumferential tread about an entire circumference of the circumferential tread.

9. The method of claim 3 , further comprising:
forming a precured tread having a first end and a second end opposite the first end;
applying the primer to the first end and the second end;
applying the adhesive to the first end and the second end; and
curing the adhesive to form the circumferential tread.

10. A method of retreading a tire without the use of a curing chamber for vulcanizing rubber, the method comprising:
determining a predetermined amount of moisture associated with controlling a release of water vapor during curing of an adhesive within an envelope;
forming a precured tire tread having a first end and a second end;
splicing the first end and the second end to form a circumferential tread having an inner surface and a road-contacting outer surface;
applying a primer to the entirety of the inner surface;
applying a moisture-curing adhesive to the entirety of the inner surface;
applying the circumferential tread to a tire casing so a bondline edge forms circumferentially about the tire casing;
wetting a moisture reservoir with the predetermined amount of moisture such that, responsive to the wetting, the water vapor is released from the moisture reservoir and permeates the bondline edge for curing the moisture-curing adhesive;
enclosing the circumferential tread, the tire casing, and the moisture reservoir within the envelope, the envelope being positioned so as to extend within grooves of the circumferential tread;
positioning the moisture reservoir proximate to the bondline edge within the envelope such that at least a portion of the circumferential tread is not covered by the moisture reservoir;
interposing a film between the bondline edge and the moisture reservoir such that the film prevents interfacing between the bondline edge and the moisture reservoir and
removing air from the envelope to apply a pressure to the circumferential tread in a direction toward the tire casing such that an additional amount of moisture is released from the moisture reservoir and directed to the bondline edge to permeate the bondline edge,
wherein the envelope is positioned within the grooves to reduce moisture circulation within the envelope, and
wherein the film is coupled to the portion of the circumferential tread that is not covered by the moisture reservoir such that the envelope comes into contact with the film when air is removed from the envelope.

11. The method of claim 10 , wherein the tire casing comprises a buffed mounting surface, the method further comprising:
applying the primer to the buffed mounting surface; and
applying the moisture-curing adhesive to the primer disposed on the buffed mounting surface.

12. The method of claim

Assignees

• Bridgestone Bandag Llc

Inventors

• Li Yichen
• Otting Robert G
• Bender David L

Classifications

• B29D2030/544

  Applying an intermediate adhesive layer, e.g. cement or cushioning element between carcass and tread · CPC title

• B29D30/56 Primary

  Retreading with prevulcanised tread {(B29D30/542 takes precedence)} · CPC title

• B29D30/542 Primary

  using envelopes or membranes provided with sealings for curing · CPC title

• B29D30/54

  Retreading · CPC title