JP5577847B2 - Rehabilitated tire and manufacturing method thereof - Google Patents

Description

  The present invention relates to a retread tire using a precure tread and a method for manufacturing the retread tire. More specifically, the present invention aims at shortening the retreading operation time by omitting the stapler process and effectively preventing peeling between the ends of the precure tread. The present invention relates to a retreaded tire and a manufacturing method thereof.

  Conventionally, when a used tire is rehabilitated, a tread portion of a used tire is polished to form a base tire, and a new tread is bonded to the base tire whose tread portion is polished. ing. In particular, the rehabilitation method using a precured precure tread has the advantage that the rehabilitation equipment is not complicated and the rehabilitation work can be easily performed.

  In such a precure tread type rehabilitation method, the end of the precure tread is wound by winding the precure tread around the base tire through an adhesive rubber layer, and driving stapler needles at both ends thereof. Prevents peeling between parts. However, extra man-hours are required to drive and remove the stapler needle, which is a factor that reduces the productivity of retreaded tires.

  In addition, it has been proposed to eliminate the stapler process by forming concave and convex portions that are engaged with each other within the tread surface at both ends of the precure tread (see, for example, Patent Document 1). However, the uneven portions that are engaged with each other in the tread surface in this manner cannot sufficiently suppress the precure tread from jumping in the tire radial direction, and the precure tread ends are not necessarily peeled off. It cannot be prevented sufficiently.

JP 2008-1067 A

  An object of the present invention is to provide a retreaded tire and a method for manufacturing the retreaded tire that can reduce the rehabilitation work time by omitting the stapler process and can effectively prevent the end portions of the precure treads from peeling off each other. It is in.

To achieve the above object, a retread tire according to the present invention is a retread tire in which a belt-shaped precure tread is wound around a base tire via a rubber layer for adhesion, and a gauge is attached to one end of the precure tread. In the precure tread, at least one projection formed based on the change and extending in the thickness direction is provided, and the other end of the precure tread is engaged with the one end having the boss . The protrusion is selectively disposed in a land portion partitioned by a groove, and the precure tread is joined to the base tire by engaging both ends thereof.

In addition, a method for producing a retread tire according to the present invention for achieving the above object is the method for producing a retread tire in which a belt-like precure tread is wound around a base tire through an adhesive rubber layer. At least one protrusion is formed on one end of the cure tread that is molded based on a change in gauge and extends in the thickness direction, and the other end of the precured tread is connected to the one end having the protrusion. The protrusion is selectively disposed in a land portion defined by a groove in the precure tread, and the precure tread is joined to the base tire by engaging both ends thereof. It is a feature.

  In the present invention, when manufacturing a retread tire in which a belt-shaped precure tread is wound on a base tire via an adhesive rubber layer, one thickness of the precure tread is molded on the basis of a gauge change. A base tire by providing at least one protrusion extending in the vertical direction, engaging the other end of the precure tread with one end having the protrusion, and engaging the precure tread with both ends thereof By joining the two, the ends of the precure treads can be connected to each other, and at the same time, the tire radial jump can be suppressed, so that the precure tread can be firmly joined to the base tire without a stapler treatment. it can. Accordingly, it is possible to omit the stapler process and shorten the rehabilitation work time, and to effectively prevent the end portions of the precure tread from peeling off.

  In the present invention, one end of the precure tread is provided with at least one protrusion formed on the basis of a gauge change and extending in the thickness direction, and at least one protrusion protruding in the longitudinal direction in plan view is formed. And it is preferable to make the other end part of the precure tread into a shape that meshes with one end part having the protrusion and the convex part. Thereby, peeling of the edge parts of a precure tread can be prevented still more effectively.

  It is preferable that the ratio of the region where the protrusions are arranged with respect to the total width of the precure tread is 30% or more. Thereby, peeling of the edge parts of a precure tread can be prevented more reliably.

Moreover, it is necessary to selectively arrange the protrusions in the land portion defined by the grooves in the precure tread. Since the projection extends in the thickness direction of the precure tread, when the projection is provided in the region where the groove of the precure tread is disposed, the size of the projection is restricted. By selectively disposing the protrusion in the land as described above, interference between the protrusion and the groove can be avoided.

It is a meridian half section view showing a retread tire which consists of an embodiment of the present invention. It is a top view which shows the principal part of the precure tread used by this invention. It is XX arrow sectional drawing of FIG. It is sectional drawing which shows the principal part of the other precure tread used by this invention. It is sectional drawing which shows the principal part of the other precure tread used by this invention. It is sectional drawing which shows the principal part of the other precure tread used by this invention. It is a top view which shows the principal part of the other precure tread used by this invention. It is a top view which shows the principal part of another precure tread (reference example) . It is a top view which shows the principal part of another precure tread (reference example) .

  Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows a retread tire according to an embodiment of the present invention, and FIGS. 2 and 3 show its precure tread. 2 and 3, C means the tire circumferential direction.

  In FIG. 1, a base tire 1 is formed by polishing (buffing) a tread portion of a used tire, 11 is a tread portion, 12 is a sidewall portion, and 13 is a bead portion. A precure tread 2 is wound around and joined to the base tire 1 with the tread portion 11 polished on the outer periphery of the tread portion 11 via an adhesive rubber layer 3.

  The precure tread 2 is a strip having a length corresponding to the tire outer peripheral length before being bonded to the base tire 1, and is vulcanized prior to rehabilitation work. A plurality of grooves 21 are formed on the tread surface of the precure tread 2, and a plurality of land portions 22 are partitioned by these grooves 21. Here, a rib pattern is formed on the precure tread 2 by extending the plurality of grooves 21 in the tire circumferential direction, but an arbitrary pattern such as a block pattern can be formed on the precure tread 2. .

  As shown in FIGS. 2 and 3, at one end 2A of the precure tread 2, at least one protrusion 201A and at least one depression 202A which are formed on the basis of a gauge change and extend in the thickness direction are formed. Has been. These protrusions 201 </ b> A and recesses 202 </ b> A are alternately arranged along the longitudinal direction of the precure tread 2. Further, at one end portion 2A of the precure tread 2, at least one convex portion 203A and concave portion 204A protruding in the longitudinal direction in plan view are formed.

  On the other hand, the other end 2B of the precure tread 2 is shaped to mesh with the one end 2A. More specifically, the other end 2B of the precure tread 2 is formed with at least one protrusion 201B and at least one depression 202B which are formed based on a gauge change and extend in the thickness direction. These protrusions 201 </ b> B and depressions 202 </ b> B are alternately arranged along the longitudinal direction of the precure tread 2. Further, at the other end 2B of the precure tread 2, at least one convex portion 203B and concave portion 204B projecting in the longitudinal direction in plan view are formed.

  When manufacturing a retread tire using the precure tread 2 described above, first, an unvulcanized adhesive rubber layer 3 is formed on the outer periphery of the tread portion 11 with respect to the base tire 1 having the tread portion 11 polished. The precure tread 2 is wound through the two and the two end portions 2A and 2B of the precure tread 2 are engaged with each other, thereby joining the precure tread 2 to the base tire 1. At that time, the adhesive rubber layer 3 is interposed not only at the interface between the base tire 1 and the precure tread 2 but also at the interfaces between the two end portions 2A and 2B.

  In a state where the end portions 2A and 2B of the precure tread 2 are engaged with each other, the convex portion 203A is combined with the concave portion 204B, the convex portion 203B is combined with the concave portion 204A, and the projection 201A is inserted into the recess 202B. 201B is inserted into the recess 202A. Therefore, the end portions 2A and 2B of the precure tread 2 are restricted from movement in the thickness direction and at the same time, the movement in the thickness direction is restricted. As a result, the end portions 2A and 2B of the precure tread 2 are connected to each other, and at the same time, the jumping in the tire radial direction can be suppressed. After the precure tread 2 is joined to the base tire 1 in this way, the rehabilitation work is completed by vulcanizing the rubber layer 3 for adhesion.

  According to the above embodiment, since the precure tread 2 can be firmly joined to the base tire 1 without the stapler process, the recuperation time can be shortened by omitting the stapler process. It is possible to effectively prevent peeling between the end portions.

  As shown in FIG. 2, the ratio of the region in which the protrusion 201A is disposed with respect to the total width W of the precure tread 2 is preferably 30% or more. That is, in FIG. 2, when the widths of the regions where the protrusions 201A are arranged are w1, w2, and w3, respectively, it is preferable to have a relationship of (w1 + w2 + w3) /W≧0.3. Here, the width of the region where the protrusion 201 </ b> A is disposed is a width when the protrusion 201 </ b> A is projected in the longitudinal direction of the precure tread 2. Thereby, peeling of the edge parts of the precure tread 2 can be prevented more reliably.

In the precure tread 2, the protrusion 201A is selectively disposed in the land portion 22 defined by the groove 21 together with the protrusion 201B. Since the protrusions 201A and 201B extend in the thickness direction of the precure tread 2, when the protrusions 201A and 201B are provided in the region where the groove 21 of the precure tread 2 is provided, the dimensions of the protrusions 201A and 201B are restricted. Will be. However, when the protrusions 201A and 201B are provided in the land portion 22, interference between the protrusions 201A and 201B and the groove 21 can be avoided, and the protrusions 201A and 201B can be formed sufficiently large.

  4 to 9 show modifications of the precure tread used in the present invention. In FIG. 4, the protrusion 201A and the recess 202A of the end 2A of the precure tread 2 have a zigzag shape in a sectional view, and the protrusion 201B and the recess 202B of the end 2B also have a zigzag shape in a sectional view so as to be aligned therewith. Yes. In FIG. 5, a plurality of protrusions 201A and a plurality of depressions 202A are formed at the end 2A of the precure tread 2, and a plurality of protrusions 201B and a plurality of depressions 202B are also formed at the end 2B so as to be aligned therewith. Yes. In FIG. 6, the protrusions 201A and the depressions 202A of the end 2A of the precure tread 2 are rounded with chamfered corners, and the corners of the protrusions 201B and the depressions 202B of the end 2B are also chamfered so as to be aligned therewith. Has been rounded. As described above, various shapes can be adopted for the protrusions 201A and 201B and the recesses 202A and 202B.

  In FIG. 7, convex portions 203A and concave portions 204A having various shapes are formed at the end portion 2A of the precure tread 2, and convex portions 203B and concave portions 204B having various shapes are formed at the end portion 2B so as to be aligned therewith. Is formed. As described above, various shapes can be employed for the convex portions 203A and 203B and the concave portions 204A and 204B. The convex portions 203A and 203B are preferably wider on the distal end side than on the proximal end side, whereby the connectivity between the end portions of the precure tread 2 can be enhanced.

  If the number of the convex portions 203A and 203B in the precure tread 2 is too large, not only the processing becomes difficult, but also the rigidity of each of the convex portions 203A and 203B decreases. Therefore, even if it is the case where it is provided most densely, it is preferable to have one convex part 203A, 203B per 30 mm width of the precure tread 2.

  8, a single convex portion 203A and concave portions 204A on both sides thereof are formed on the end portion 2A of the precure tread 2, and a single concave portion 204B and convex portions on both sides thereof are formed on the end portion 2B so as to be aligned therewith. A portion 203B is formed. Further, a protrusion 201A and a recess 202A are formed over the entire width of the end 2A of the precure tread 2, and a protrusion 201B and a recess 202B are formed over the entire width of the end 2B so as to be aligned therewith.

  In FIG. 9, a protrusion 201A and a recess 202A are formed over the entire width of the end 2A of the precure tread 2, and a protrusion 201B and a recess 202B are formed at the end 2B so as to be aligned therewith. However, the end portions 2A and 2B of the precure tread 2 are not formed with convex portions and concave portions in plan view. Also in this case, in a state where the end portions 2A and 2B of the precure tread 2 are engaged with each other, the protrusion 201A is inserted into the recess 202B, and the protrusion 201B is inserted into the recess 202A. The end portions 2A and 2B can be firmly fixed.

  In each embodiment mentioned above, it is preferable to give the end shape of the precure tread 2 based on the shape of the mold when the precure tread 2 is vulcanized, but the end of the precure tread 2 after vulcanization You may make it provide by processing a part mechanically.

  When renewing a used tire of tire size 11R22.5 by the precure tread method, the retreaded tires of the conventional example, the comparative example 1 and the examples 1 and 2 are obtained by changing the structure of the precure tread as shown in Table 1. Got.

  In Table 1, when “protrusions” are present, one end of the precure tread is provided with a protrusion formed on the basis of gauge change and extending in the thickness direction, and the other end of the precure tread is connected to one end. This means that the shape meshes with the part. Further, when there is a “convex portion”, a convex portion protruding in the longitudinal direction in a plan view is formed at one end portion of the precure tread, and the other end portion of the precure tread is engaged with the one end portion. It means having a shape.

  About these test tires, the working time and the peeling rate were evaluated by the following evaluation methods, and the results are also shown in Table 1.

Working hours:
For each test tire, the molding time per tire during rehabilitation was measured. The evaluation results are shown as an index with Conventional Example 1 as 100. The smaller the index value, the better the molding workability during rehabilitation. In addition, in the conventional example, the stapler process was performed in order to fix the both ends of the precure tread, and in the comparative example 1 and Examples 1-2, the stapler process was not performed.

Peeling rate:
About each test tire, the ratio which the junction part of a precure tread peels in the state of the retreaded tire after vulcanization was calculated | required. The evaluation results are shown as an index with Conventional Example 1 as 100. It means that the smaller the index value, the smaller the rate at which the joint portion of the precure tread is peeled off. Here, the stapler processing was not performed in all of the conventional example, the comparative example 1, and the examples 1 and 2.

  As is clear from Table 1, the tires of Examples 1 and 2 have excellent molding workability at the time of rehabilitation as compared with the conventional example, and effectively prevent peeling between the ends of the precure tread. I was able to. On the other hand, the tire of Comparative Example 1 did not achieve the improvement effect as in Examples 1 and 2.

1 tire 2 Precured tread 3 Adhesive rubber layer 11 Tread part 12 Side wall part 13 Bead part 21 Groove 22 Land part 201A, 201B Protrusion 202A, 202B Depression 203A, 203B Convex part 204A, 204B Concave part

Claims (6)

In a retread tire in which a belt-shaped precure tread is wound around a base tire via a rubber layer for adhesion, at least one end of the precure tread is molded based on a gauge change and extends in the thickness direction. One protrusion is provided, the other end of the precure tread is engaged with one end having the protrusion, and the protrusion is selectively placed in a land portion defined by a groove in the precure tread. A retread tire characterized by being arranged and joined to the pedestal tire by engaging the precure tread with both ends thereof engaged with each other.   At least one protrusion formed on one end of the precure tread and extending in the thickness direction is formed based on a change in gauge, and at least one protrusion protruding in the longitudinal direction in plan view is formed. The rehabilitated tire according to claim 1, wherein the other end portion of the cure tread is configured to mesh with the one end portion having the protrusion and the convex portion.   The rehabilitated tire according to claim 1 or 2, wherein a ratio of a region in which the protrusion is disposed with respect to a total width of the precure tread is set to 30% or more. In a method for manufacturing a retread tire in which a belt-shaped precure tread is wound through a rubber layer for adhesion to a base tire, the thickness direction is formed on one end of the precure tread based on a gauge change At least one projection extending to the other end of the precure tread so that the other end of the precure tread is engaged with the one end having the projection, and the projection is formed in a land portion defined by a groove in the precure tread. Is selectively disposed, and the precure tread is joined to the base tire by engaging both ends thereof with each other. At least one protrusion formed on one end of the precure tread and extending in the thickness direction is formed based on a change in gauge, and at least one protrusion protruding in the longitudinal direction in plan view is formed. The method for manufacturing a retread tire according to claim 4 , wherein the other end portion of the cure tread is shaped to mesh with the one end portion having the protrusion and the convex portion. The method for manufacturing a retread tire according to claim 4 or 5 , wherein a ratio of a region in which the protrusion is disposed with respect to a total width of the precure tread is set to 30% or more.

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