Method for producing a tire, in particular a retreaded tire, and retreaded tire produced according to said method

Abstract

In a retreaded tire, a bridge strip (8) is secured to an edge region (6) of a new tread (4) and the adjacent region of an adjacent side wall (7). The bridge strip (8) cures during the bonding of the new tread (4) to an already vulcanized base (1). The bridge strip (8) prevents the edge region (6) of the new tread (4) from detaching and contributes to a high load-bearing capacity of the tire.

Description

[0001] 202404137

[0002] - 1 - Description

[0003] Method for manufacturing a tire, in particular a retreaded tire and retreaded tires manufactured according to the method

[0004] The invention relates to a method for manufacturing a tire, in particular a retreaded tire for a vehicle, with a tread to be applied to a previously vulcanized tire base body. The invention further relates to a retreaded tire for a vehicle manufactured according to a method of the preceding claims, comprising a previously vulcanized tire base body, a new tread attached to the previously vulcanized tire base body, and two sidewalls.

[0005] To manufacture a retreaded tire, pre-vulcanized tread strips are attached to a pre-vulcanized tire base, the carcass of a worn tire. After the worn tread is removed, the tire base is ground. The ground tire base now has a specific roughness. A special rubber compound is applied between the tire base and the new tread, which bonds the tread to the carcass during subsequent vulcanization. In most retreading processes, the sidewalls remain untouched and unchanged. However, the combination of an old sidewall and a new tread can lead to tread separation during operation of the retreaded tire.

[0006] The invention addresses the problem of designing a method of the type mentioned above in such a way that the detachment of the newly applied tread on an already vulcanized tire base, particularly a retreaded tire, is largely avoided. Furthermore, the invention addresses the problem of creating a retreaded tire manufactured according to the method which exhibits high load-bearing capacity during operation.

[0007] The first-mentioned problem is solved according to the invention by attaching a bridging strip to an edge region of the tread and an adjacent region of a neighboring side wall. 202404137

[0008] - 2 -

[0009] This design stabilizes the area between the newly applied tread and the adjacent sidewall area with the bridging strip. This stabilization prevents the tread from separating from the rest of the tire at this point. The desired properties of the bridging strip can be easily achieved by selecting a suitable material and thickness.

[0010] According to another advantageous embodiment of the invention, applying the bridge strip is particularly easy if the bridge strip is applied as unvulcanized rubber to the tread and the area adjacent to the tread and is subsequently vulcanized.

[0011] According to another advantageous embodiment of the invention, further simplifying the application of the bridge strip is achieved by applying the unvulcanized rubber to the edge area of ​​the tread and the adjacent area of ​​the side wall via a mixing roller.

[0012] According to another advantageous embodiment of the invention, simplifying tire manufacturing involves curing the bridging strip during the bonding of the tread to the already vulcanized tire base body. This design minimizes the additional work required for applying the bridging strip. Curing and bonding of the tread to the already vulcanized tire base body preferably take place in an autoclave.

[0013] According to another advantageous embodiment of the invention, the bridge strip can be manufactured with the desired material properties if it is made of a material different from that of the sidewalls. A special component can be used as the material for the bridge strip, which, for example, has particularly high adhesive properties on the new tread and the existing sidewalls of the worn tire. The material of the bridge strip can have a special aesthetic design, for example, by covering irregularities in the area between the tread and the sidewall, thus contributing to a visually appealing appearance of the tire. 202404137

[0014] - 3 - contribute. The material of the bridge strip can also exhibit particularly high resistance to abrasion.

[0015] According to another advantageous embodiment of the invention, the bridge strip can be manufactured particularly cost-effectively if the bridge strip is made from the same material as the side walls.

[0016] According to another advantageous embodiment of the invention, to further increase the stability of the edge areas of the running track and adjacent areas of the side walls, it contributes if the bridge strip has a predetermined thickness and is designed to be raised above the adjacent areas of the side walls.

[0017] The second problem mentioned, namely the creation of a retreaded tire manufactured according to the method which has a high load-bearing capacity in operation, is solved according to the invention by a bridging strip covering an edge area of ​​the tread and an adjacent area of ​​sidewalls.

[0018] This design prevents the edge of the tread from separating from the sidewall. The retreaded tire manufactured using this method has a visually appealing appearance.

[0019] According to another advantageous embodiment of the invention, the material required for the bridging strip can be kept particularly low if the bridging strip is arranged in equal parts on the edge region of the tread and on the adjacent sidewall. This also keeps the manufacturing costs for the retreaded tire low when a costly special component is used for the bridging strip.

[0020] The invention allows for numerous embodiments. To further illustrate its basic principle, two of these are shown in the drawing and described below. This drawing shows a single figure depicting half a cross-section through a retreaded tire, 202404137.

[0021] - 4 -

[0022] The figure schematically shows half of a retreaded tire in cross-section. The retreaded tire has a vulcanized tire base body 1. The vulcanized tire base body 1 is a so-called carcass of a used tire. Belt inserts 2, bead cores 3, and the like, which are common in modern tires, are shown only schematically in the tire base body 1 for the sake of simplicity. A tread 4 is attached to the tire base body 1 by means of a curable rubber compound 5. The edge region of the tread 6 and an adjacent area of ​​a sidewall 7 of the tire are covered by a bridging strip 8. The bridging strip 8 connects the edge of the tread 4 with the adjacent area of ​​the sidewall 7. In this embodiment, the bridging strip 8 extends equally over the edge region 6 of the tread 4 and the sidewall 7.

[0023] To manufacture a retreaded tire, the worn tread is removed from a worn tire. This creates the tire base body 1. The new tread 4, shown in the illustration, is then pushed onto the tire base body 1 in a pre-cured state using the curable rubber compound 5. A rubber-elastic material made of unvulcanized rubber is then applied to the edge 6 of the tread 4 and the adjacent area of ​​the sidewall 7 using a mixing roller. The pre-cured tread 4 is then cured in an autoclave or hot mold and bonded to the tire base body 1 via the curable rubber compound 5. The unvulcanized rubber applied by the mixing roller cures to form the bridge strip 8. Any known heating medium, such as steam or hot water, can be used for the curing process.

[0024] 202404137

[0025] - 5 -

[0026] Reference symbol list

[0027] 1 tire base body

[0028] 2 Belt insert 3 Bead core

[0029] 4 treads

[0030] 5 Rubber compound

[0031] 6 Edge area

[0032] 7 Side wall 8 Bridge strip

Claims

202404137 -6- Patent claims 1. Method for manufacturing a tire, in particular a retreaded tire for a vehicle with treads (4) to be applied to an already vulcanized tire base body (1), characterized in that a bridge strip (8, 108) is attached to an edge area (6) of the tread (4) and an adjacent area of ​​an adjacent sidewall (7).

2. Method according to claim 1, characterized in that the bridge strip (8) is applied as unvulcanized rubber to the running strip (4) and the area adjacent to the running strip (4) and is subsequently cured.

3. Method according to claim 2, characterized in that the unvulcanized rubber is applied via a mixing roller to the edge area (6) of the tread (4) and the adjacent area of ​​the side wall (7).

4. Method according to at least one of claims 1 to 3, characterized in that the bridge strip (8) is cured during the joining of the tread (4) with the already vulcanized tire base body (1).

5. Method according to at least one of claims 1 to 4, characterized in that the bridge strip (8) is made of a material different from the material of the side walls (7).

6. Method according to at least one of claims 1 to 4, characterized in that the bridge strip (8) is made of the same material as the side walls (7).

7. Method according to at least one of claims 1 to 6, characterized in that the bridge strip (8) has a predetermined thickness and is designed to be raised above the adjacent areas of the side walls (7). 202404137 -7 - 8. Retreaded tire for a vehicle manufactured according to a method of the preceding claims, comprising a tire base body (1) that has already been vulcanized, a new tread (4) attached to the tire base body (1), and two sidewalls (7), characterized in that a bridging strip (8, 108) covers an edge region (6) of the tread (4) and an adjacent region of sidewalls (7).

9. Retreaded vehicle tire according to claim 8, characterized in that the bridge strip (8) is arranged in equal parts on the edge area (6) of the tread (4) and on the adjacent sidewall (7).

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