WO2015130302A1

WO2015130302A1 - Improved tire repair patch application

Info

Publication number: WO2015130302A1
Application number: PCT/US2014/019312
Authority: WO
Inventors: E. Bruce Colby; Cesar E. ZARAK; Michael WIDMYER; Glenn Andrew GORDON
Original assignee: Compagnie Generale Des Etablissements Michelin; Michelin Recherche Et Technique, S.A.
Priority date: 2014-02-28
Filing date: 2014-02-28
Publication date: 2015-09-03

Abstract

An improved method for application of a tire repair patch is provided. The use of cement for the application of the repair patch can be eliminated so as to avoid delays necessitated by drying time and the release of VOCs. Alternatively, cement can be pre-applied separately to the patch to avoid delays due to drying time and to facilitate the confinement of VOCs released during drying.

Description

IMPROVED TIRE REPAIR PATCH APPLICATION

FIELD OF THE INVENTION

[0001] The subject matter of the present disclosure relates generally to the application of a tire repair patch.

BACKGROUND OF THE INVENTION

[0002] Tires can be damaged during use from impact or collision with e.g., objects in the roadway. In some cases, the impact may be severe enough to puncture the tire and create an opening in the inner liner leading to a loss of gas (e.g., air) needed for proper inflation pressure. In other cases, the damage may not immediately create a loss of inflation pressure but may still cause damage requiring a repair that includes the inner liner.

[0003] In some cases, the damage to a tire may be repairable. Repair of the inner liner typically includes the application of a patch in a process that involves the use of cement. The cement is applied to a repair surface that is specifically prepared for application of the patch. The use of cement lengthens the time required for tire repair because of the additional time needed to allow drying of the cement. For example, depending on the cement composition, 10 to 15 minutes or more may be required for cement drying.

[0004] Additionally, the cement will typically include VOCs or volatile organic compounds. For this reason, such tire repairs must typically be performed under a hood or other area where proper ventilation is provided. Provision must be made for storage of the cement, which may be significant in a commercial facility where multiple tire repairs are made daily such as e.g., a facility where tire retreading is performed.

[0005] Tire repair is very often coupled with tire retreading. One difficulty in removing the cement from the repair process is that retreading involves an inflation step, after the repair has been made, and before the tire is submitted to curing in autoclave. The cement provides tack needed to hold the patch in place during the retreading process. So, any attempt to eliminate cement generally must replace much of this tack.

[0006] Accordingly, eliminating or minimizing the use of cement in the patch application process of tire repair is desirable. More particularly, a reduction or elimination of VOCs from a tire repair facility or tire retreading facility would be useful in minimizing ventilation and storage requirements. Additionally, the elimination of cement drying time from the patch application process would be useful for increasing the efficiency of tire repair. Still further, it is believed that for certain applications, the elimination of cement from the patch application process can result in improved cure adhesion between certain surfaces of the repair.

SUMMARY OF THE INVENTION

[0007] The present invention provides an improved method for application of a tire repair patch. The use of cement for the application of the patch can be eliminated so as to avoid delays necessitated by drying time and the release of VOCs. Alternatively, cement can be pre-applied separately to the patch to avoid delay in drying time and to facilitate the confinement of VOCs released during drying. Additional objects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.

[0008] In one exemplary aspect of the invention, a method of applying a repair patch to a damaged portion of a tire is provided that includes the steps of applying cement to a bonding surface of the patch before application of the patch to the tire; drying the cement dry substantially before application of the patch to the tire; preparing the surrounding surface of the damaged portion of the tire for application of the patch; pressing the patch onto the damaged portion of the tire; and curing at least part of the damaged portion of the tire.

[0009] In another exemplary aspect, the present invention provides a cementless method of applying a repair patch to a damaged portion of a tire. This exemplary method includes the steps of locating the damaged portion of the tire; grinding a surrounding surface of the damaged portion of the tire for application of the patch; repeatedly contacting and removing bonding compound over the surface created by the grinding step in a manner that removes residue from the surface for bonding with the repair patch; pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the surface treated by the grinding step and positions the patch over the damaged portion without the use of cement; and curing at least part of the damaged portion of the tire.

[0010] According to another exemplary aspect of the present invention, a cementless method of applying a repair patch to a damaged portion of a tire is provided that includes the steps of locating the damaged portion of the tire; preparing the surrounding surface of the damaged portion for application of the patch, the step of preparing including creating an opening at the damaged portion of the tire for receipt of the patch; positioning bonding rubber onto the tire in a manner that completely surrounds the opening created at the damaged portion; pressing the patch onto the damaged portion of the tire in a manner that contacts the bonding layer of the patch with the added bonding rubber bonding rubber and positions the patch over the opening without the use of a cement; and curing at least part of the damaged portion of the tire.

[0011] In still another exemplary aspect, a cementless method of applying a repair patch to a damaged portion of a tire is provided. This exemplary method includes the steps of locating the damaged portion of the tire; grinding a surface surrounding the damaged portion of the tire for application of the patch; refreshing the surface treated by the grinding step with a mild abrasive; pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the surface treated by the refreshing step and positions the patch over the damaged portion without the use of a cement; and curing at least part of the damaged portion of the tire.

[0012] In another exemplary aspect, a cementless method of applying a repair patch to a damaged portion of a tire is provided that includes the steps of locating the damaged portion of the tire; preparing the surrounding surface area of the damaged portion for application of the patch, the step of preparing including creating a suitable surface at the damaged portion of the tire for receipt of the patch; heating the patch, including a bonding layer, so as to soften the bonding layer; pressing the patch onto the damaged portion of the tire in a manner that positions the patch over the opening without the use of a cement; and curing at least part of the damaged portion of the tire.

[0013] In another exemplary aspect, the present invention provides a cementless method of repairing a damaged portion of a tire. This exemplary, cementless method includes the steps of locating the damaged portion of the tire; preparing the surrounding surface of the damaged portion for application of a patch that comprises a cloth separator and a layer of cured rubber material, the step of preparing including creating a suitable surface at the damaged portion of the tire for receipt of the patch; positioning a layer of uncured bonding rubber onto the tire in a manner that covers and surrounds the opening created at the damaged portion; removing the cloth separator from the layer of cured rubber material of the patch; pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the uncured bonding rubber and positions the patch over the opening without the use of a cement, wherein the step of pressing occurs immediately after the step of removing; and curing at least part of the damaged portion of the tire.

[0014] These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

[0016] FIG. 1 provides a perspective view of a portion of an exemplary tire including a partial cross-section through a meridian plane. A damaged portion of the tire is also shown.

[0017] FIG. 2 is a perspective view of the portion of the exemplary tire shown in FIG. 1 with an exemplary opening created in the damaged portion of the tire in preparation for patch application.

[0018] FIG. 3 is a cross-section of the tire taken along line 3-3 of FIG. 2.

[0019] FIG. 4 illustrates the exemplary opening created in the tire of FIG. 2 as viewed from the interior of the tire.

[0020] A perspective view of an exemplary patch as may be used with the present invention is shown in FIG. 5.

[0021] FIG. 6 is a perspective view of the steps of creating another exemplary patch as may be used with the present invention. DETAILED DESCRIPTION

[0022] For purposes of describing the invention, reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0023] FIG. 1 provides a perspective view of a cross-section of a tire 100 having a damaged portion 102 along a sidewall 104. The cross-section is taken along a meridian plane of tire 100. Tire 100 includes a sidewall 102 that extends between a bead portion 106 and a crown portion 108, which includes a tread portion 110. A body ply 116 extends from bead portion 106 through sidewall 104 and crown portion 108. Tire 100 includes an inner liner 112 along the interior 114 of tire 100, which serves to maintain inflation pressure.

[0024] Damaged portion 102 may include a tear, laceration, puncture, or other damage 98 to tire 100 caused by e.g., impact or collision with another object. The size of the damaged portion 102 may differ from the example shown in FIG. 1 and/or may be located at other positions on tire 100. Although shown with a tread portion 110, it should be understood that the present invention may also be used to repair a tire for which the tread portion 110 has been removed as part of a retreading operation. Depending upon the severity of the injury, the damaged portion 102 of tire 100 may create an opening or leak in inner liner 112 that prevents tire 100 from holding inflation pressure. Additionally, the damaged portion 102 may include breaks or other damage to one or more cords 118 in body ply 116.

[0025] In one exemplary method, the repair of tire 100 includes locating the damaged portion 102 and then preparing it for application of the patch. As shown in FIG. 2, such preparation may include cutting the rubber materials of tire 100, in this example sidewall 102, to create an opening 120 having a specific shape such as e.g., a polygon of length L and width W. Opening 120 may be, for example, large enough to remove damaged materials from portion 102 while small enough and of a proper shape for application of a patch (it being understood, however, that the shape of opening 120 and the patch may be different). Such preparation may also include cutting one or more damaged cords 118. Typically, opening 120 is created completely through tire 100 extending between the interior 114 and exterior 122 of tire 100.

[0026] Referring to FIGS. 3 and 4, for this exemplary method, preparation will also include removal of some of the inner liner 112 of tire 100 to create a prepared surface 124 for patch application. As shown, prepared surface 124 forms part of the inner liner 112 located at damaged portion 102. Surface 124 surrounds opening 120 and is immediately adjacent to opening 120 for this embodiment. By way of example, the removal of material can be performed by e.g., grinding, buffing, or other actions that can roughen the surrounding surface 124 and remove contaminants from surrounding surface 124. Generally, the size of the surrounding surface 124 that is prepared corresponds to an area slightly larger than the size of the patch 126 that will be used for the repair.

[0027] An exemplary patch 126, as shown in FIG. 5, is selected for application at a position over the opening 120 of inner liner 112. Patch 126 is configured in a size and shape that will cover opening 120 and sufficiently contact surface 124. Patch 126 may include multiple additional layers and have a shape different than what is shown in FIG. 5. For this particular embodiment, patch 126 includes a protective layer 128 placed onto bonding surface 130 of a bonding layer 132 constructed from uncured rubber. However, in other

embodiments, patch 126 may be reinforced by e.g., one or more additional layers placed onto side 134 of bonding layer 132. For example, as shown in FIG. 6, patch 126 may include one or more additional layers of cured rubber 144 and 148 that are positioned (arrow P) onto side 134 of the uncured rubber used for bonding layer 132. Layers 144 and 148 have a protective cloth layer 142 on surface 146 opposite to surface 150. Protective layer 142 is removed and then the conglomerate of cured layers 144 and 148 are positioned onto bonding layer 132 of patch 126. Cloth layer 142 helps provide a clean, textured surface 146 for application to surface 134 and aids in removal from the molding surface.

[0028] Returning to FIG. 4, conventionally a bonding cement would be applied to surface 124 around opening 120. As previously indicated, a drying time would be required while VOCs are released from the cement, which would necessitate proper ventilation. Once the cement was dried, a patch would be placed in contact with the cement over opening 120. The cement promotes a necessary tack between the surface 124 and the desired patch and provides a seal between surface 124 and patch 126. Typically, surface 124 is not perfectly smooth after grinding, and the cement helps prevent gas leakage between the patch and surface 124. In addition, during e.g., a retreading operation, the cement assists in holding the patch in place during the retreading process. The inventors, however, have discovered that these issues can be overcome as will now be further described.

[0029] In one exemplary aspect of the present invention, cement is applied to the bonding surface 130 on layer 132 of patch 126. The cement is allowed to dry substantially before application to tire 100. Because the cement is applied to patch 126, this exemplary step advantageously allows patch 126 to be prepared in advance of other steps in the repair patch application process. As such, the time required for drying of the cement can be can be easily masked, thereby shortening the time for patch application to a damaged tire. In addition, because of e.g., the smaller size of patch 126 relative to tire 100, patch 126 can be readily placed into a hood or other ventilated area prior to application to tire 100 so as to more effectively confine and exhaust VOCs and prevent their migration to the rest of a tire repair or retread facility.

[0030] Once the cement is dried, patch 126 is pressed onto the damaged portion 102 of tire 100 with the cement on patch 126 contacting surface 124 around opening 120. The freshness of the prepared surface 124 and the fresh cement layer on the patch provide sufficient tack and adhesion. Depending on the size of the opening 120, repair rubber may now be placed in the opening from the exterior side 122 of tire 100 to fill the opening against patch 126. For retreading operations, if the location of the damaged portion 102 is in the crown portion 108 of tire 100, a new tread portion 110 may be placed on the tire 100, which is typically buffed in preparation for the new tread. Tire 100 is then placed into an autoclave or other device where heat and pressure are applied. These conditions cure the damaged portion of tire 100 or, more particularly, the uncured rubber components of patch 126 and the repair rubber. For retreading operations, the new tread portion 110 will also be cured to the buffed tire.

[0031] In another exemplary aspect of the present invention, the use of cement can be eliminated from the process of applying repair patch 126. After locating the damaged portion 102, creating opening 120, and preparing surface 124 by e.g., grinding as described above, surface 124 is repeatedly contacted with a bonding compound. For example, the bonding compound may be a portion of uncured rubber that is specially formulated to adhere to surface 124 created by the grinding step. The uncured rubber is repeatedly placed into contact with surface 124 and then removed from surface 124. The tackiness of the bonding compound removes residue created during the grinding step and/or other contaminants that could interfere with proper bonding of patch 126. In addition, it is believed such repeated contacting can help activate surface 124 to further enhance tack and bonding. In one exemplary aspect, this step can be performed using a tack roller 136 (FIG. 3) that includes the bonding compound 138. Tack roller 136 is moved repeatedly back and forth (arrows S) over surface 124. After such repeated application of the bonding compound, patch 125 is pressed onto surface 124 of tire 100 (without the use of cement) and further steps may be completed (e.g., filling, retreading) as described above before placing tire 100 into an autoclave or other device where heat and pressure are applied.

[0032] In another cementless, exemplary aspect of the invention, a thin element of bonding rubber is positioned onto surface 124 surrounding the damaged portion. More particularly, after locating the damaged portion 102, creating opening 120, and preparing surface 124 by e.g., grinding, a thin element of an uncured, bonding rubber 140 is applied to surface 124 in a manner that provides a high tack bond that completely surrounds opening 120 as shown in FIG. 4. Preferably, bonding rubber 140 is applied to all of the prepared, surrounding surface 124. Bonding rubber 140 may be hot extruded or applied as a layer and stitched. Protective layer 128 of patch 126 is then removed from the bonding layer 132 of uncured rubber 132, and then patch 126 is pressed to surface 124 and bonding rubber 140. The presence of the extra layer of bonding rubber on the periphery of the damaged area sufficiently tacks the repair to the tire, seals any irregularities, blocks any air pathways, and prevents air from migrating from the inside of the tire through the injury during the inflation step of the retreading process. Further steps may be completed (e.g., filling, retreading) as described above before placing tire 100 into an autoclave or other device where heat and pressure are applied.

[0033] In still another cementless, exemplary aspect of the present invention, the prepared tire surface 124 is refreshed using a mildly abrasive cleaner. For example, after locating the damaged portion 102, creating opening 120, and preparing surface 124 by e.g., grinding as described above, surface 124 is refreshed with a mild abrasive. By way of example, the mild abrasive could be Scotchbrite™ that is used to rub surface 124. Such refreshment helps to remove residual debris from surface 124 and promotes better tack and adhesion with patch 126. After pressing patch 126 onto the refreshed surface 124 without the use of cement, further steps may be completed (e.g., filling, retreading) as described above before placing tire 100 into an autoclave or other device where heat and pressure are applied.

[0034] In another exemplary aspect of the present invention, patch 126 with bonding layer 132 is heated. More particularly, as set forth previously, the damaged portion 102 of tire 100 is located, opening 120 is created, and surface 124 is prepared as described above. Using a heat source such e.g., a hot pad or other device, bonding layer 132 of patch 126 is heated to so as to soften the bonding layer thereby increasing its tack and wetting capability. After pressing patch 126 onto the refreshed surface 124 without the use of cement, further steps may be completed (e.g., filling, retreading) as described above before placing tire 100 into an autoclave or other device where heat and pressure are applied.

[0035] In still another exemplary embodiment of the present invention, an additional cementless method of repair of tire 100 is provided. After locating the damaged portion 102, it is prepared for application of the patch (e.g., creating a buffed surrounding surface 124 in the vicinity of the opening at the damaged portion of the tire). Then, a layer of uncured, bonding rubber 132 is positioned onto the tire in a manner that covers the prepared area 124 at damaged portion 102. Preferably, bonding rubber 132 is applied to all of the prepared, surrounding surface 124. Next, a cloth separator 142 or other protective layer is removed from one or more layers of cured rubber such as e.g., layers 144 and 148 as shown in FIG. 6. The removal of the protective layer 142 is performed immediately prior to the application of layers 144 and 148 to tire 100 such that surface 146 is clean and sufficiently fresh for positioning onto layer 132. After removal of protective layer 142, the cured layers 144 and 148 are pressed onto the uncured layer of bonding rubber 132 so as to cover all of surface 134. Tire 100 is then subjected to a curing step as previously described.

[0036] While the present subject matter has been described in detail with respect to specific exemplary embodiments and methods thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Steps from various exemplary aspects of the invention as set forth above may be combined to provide still additional exemplary aspects of the invention. For example, the refreshing step can be combined with the steps of heating the patch and/or applying bonding compound. Other combinations may also be used. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art using the teachings disclosed herein.

Claims

WHAT IS CLAIMED IS:

1. A method of applying a repair patch to a damaged portion of a tire, the method comprising the steps of:

applying cement to a bonding surface of the patch before application of the patch to the tire;

drying the cement dry substantially before application of the patch to the tire;

preparing the damaged portion of the tire for application of the patch;

pressing the patch onto the damaged portion of the tire; and

curing at least part of the damaged portion of the tire.

2. The method of applying a repair patch to a damaged portion of a tire as in claim 1 , further comprising the step of placing the patch within a hood or other ventilated area during the step of drying.

3. The method of applying a repair patch to a damaged portion of a tire as in claim 1 , further comprising the step of exhausting volatile organic compounds released from the cement during the step of drying.

4. The method of applying a repair patch to a damaged portion of a tire as in claim 1 , wherein the step of preparing comprises creating an opening at the damaged portion of the tire.

5. The method of applying a repair patch to a damaged portion of a tire as in claim 4, wherein the step of preparing comprises grinding an inner liner of the tire at a surface surrounding the opening from the step of creating.

6. A cementless method of applying a repair patch to a damaged portion of a tire, the method comprising the steps of:

locating the damaged portion of the tire;

grinding a surface surrounding the damaged portion of the tire for application of the patch; repeatedly contacting and removing bonding compound over the surface of the grinding step in a manner that removes residue from the surface for bonding with the repair patch;

pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the surface treated by the grinding step and positions the patch over the damaged portion without the use of cement; and

curing at least part of the damaged portion of the tire.

7. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 6, wherein the bonding compound comprises an uncured rubber that is formulated to adhere to the surface treated by the grinding step.

8. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 6, wherein the step of repeatedly contacting and removing comprises moving a tack roller including the bonding compound over the surface treated by the grinding step.

9. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 6, further comprising the step of creating an opening at the damaged portion of the tire.

10. A cementless method of applying a repair patch to a damaged portion of a tire, the method comprising the steps of:

locating the damaged portion of the tire;

preparing the damaged portion for application of the patch, the step of preparing including creating an opening at the damaged portion of the tire for receipt of the patch; positioning bonding rubber onto the tire in a manner that completely surrounds the opening created at the damaged portion;

pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the bonding rubber and positions the patch over the opening without the use of a cement; and

curing at least part of the damaged portion of the tire.

11. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 10, wherein the step of positioning comprises:

applying an extra layer of the bonding compound around the damaged portion; and stitching the layer of bonding compound to the tire.

12. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 10, wherein the step of positioning comprises extruding the bonding compound onto the tire around the damaged portion.

13. A cementless method of applying a repair patch to a damaged portion of a tire, the method comprising the steps of:

locating the damaged portion of the tire;

grinding a surface of the damaged portion of the tire for application of the patch; refreshing the surface treated by the grinding step with a mild abrasive;

pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the surface treated by the refreshing step and positions the patch over the damaged portion without the use of a cement; and

curing at least part of the damaged portion of the tire.

14. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 13, further comprising the step of creating an opening at the damaged portion of the tire, wherein the surface treated during the grinding step is located around the opening.

15. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 14, further comprising the steps of:

applying a layer of the bonding compound around the opening; and

stitching the layer of bonding compound to the tire.

16. The cementless method of applying a repair patch to a damaged portion of a tire as in claim 14, further comprising the step of extruding a bonding compound onto the tire around the opening.

17. A cementless method of applying a repair patch to a damaged portion of a tire, the method comprising the steps of:

locating the damaged portion of the tire;

preparing the damaged portion for application of the patch, the step of preparing including creating an opening at the damaged portion of the tire for receipt of the patch; heating the patch, including a bonding layer, so as to soften the bonding layer;

pressing the patch onto the damaged portion of the tire in a manner that positions the patch over the opening without the use of a cement; and

curing at least part of the damaged portion of the tire.

18. A cementless method of repairing a damaged portion of a tire, the method comprising the steps of:

locating the damaged portion of the tire;

preparing the damaged portion for application of a patch that comprises a cloth separator and a layer of cured rubber material, the step of preparing including creating an opening at the damaged portion of the tire for receipt of the patch;

positioning a layer of uncured bonding rubber onto the tire in a manner that covers and surrounds the prepared surface area created at the damaged portion;

removing the cloth separator from the layer of cured rubber material of the patch; pressing the patch onto the damaged portion of the tire in a manner that contacts the patch with the uncured bonding rubber and positions the patch over the opening without the use of a cement, wherein the step of pressing occurs immediately after the step of removing; and

curing at least part of the damaged portion of the tire.