JP2006346886A - Tire manufacturing method and tire groove forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire manufacturing method capable of enhancing the degree of freedom of the design of a groove pattern and capable of efficiently forming grooves, and a tire groove forming device. <P>SOLUTION: The tire groove forming device 20 comprises a rotary drive part 24 receiving a tire 10 in a detachable manner and rotating the attached tire 10 around a tire rotary shaft, and the grinder type grinding part 26 brought into contact with a tread part 16 of the tire 10 attached to the rotary drive part 24 to grind a part of the rubber material constituting the surface part of a tread part 16, and is constituted so that a grinder 32 is brought into contact with the tread part 16 while rotating the tire 10 and a part of the rubber material constituting the surface part of the tread part 16 is ground while rotating the tire 10. Accordingly, the ground refuse produced by this grinding is easily removed from the grooves. As a result, the degree of freedom of the design of the groove pattern can be enhanced and the grooves can be efficiently formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a tire manufacturing method and a tire groove forming apparatus for forming a groove in a tread portion after vulcanization molding, and more particularly, an optimum tire manufacturing method for use in manufacturing a large tire such as an ORR. And a tire groove forming apparatus.

  When manufacturing a tire such as a pneumatic tire, a groove is usually formed during vulcanization by providing a blade in a vulcanizer.

  By the way, in the vulcanization of large tires such as ORR, there is a problem that the groove shape is restricted in consideration of facilitating removal of the mold from the vulcanized tire in either the split mold or the full mode. was there. For example, in the lug groove, the groove is shallow on the tire center side. Further, in the thick groove (main groove) extending in the tire circumferential direction, the taper angle is increased with respect to the mold drawing direction. Thus, this problem is exacerbated in deep groove designs.

  In addition, if a taper is formed on the narrow groove extending in the tire circumferential direction, problems such as a decrease in rigidity of the land portion occur. Therefore, it is not preferable to form the taper in the narrow groove. Therefore, this problem has become serious even in the narrow groove design, which hinders improvement in tire performance. If a taper is not formed in the narrow groove, the mold is difficult to come off from the tire, and the blade is bent when the mold is removed.

  As a countermeasure, it is conceivable to form a narrow groove by grooving the tread portion of the tire after vulcanization molding with a cutter.

  Here, as described above, when the thick groove is formed, the cutter 82 having a substantially V-shaped cross section as shown in FIG. 8 is used, and the angle θ is set with respect to the tire radial direction as shown in FIG. It is possible to form a thick groove 88 having a groove sidewall 89 (ie, a tapered groove sidewall). In this case, the cutting waste can be easily removed from the thick groove 88 (see, for example, Patent Document 1).

However, when forming a narrow groove, a taper cannot be formed on the groove sidewall. For this reason, it is necessary to use a cutter having a substantially U-shaped cross section, and as a result, it is difficult to remove the cutting waste 94 generated by the cutting from the narrow groove 98 as shown in FIG. Therefore, it is necessary to add a process of removing the cutting waste 94, and there is a problem that productivity is lowered. In particular, in a large tire such as ORR, this difficulty is more noticeable because the land portion 96 adjacent to the narrow groove 98 is easily subjected to a force that causes the narrow groove 98 to shrink in the tire width direction.
JP 61-177232 A

  In view of the above facts, an object of the present invention is to provide a tire manufacturing method and a tire groove forming apparatus that can improve the design freedom of the groove pattern and can efficiently form the groove. .

  The invention according to claim 1 is a tire manufacturing method for forming a groove in a tread portion of a tire after vulcanization molding, and by grinding a part of a rubber material constituting a surface portion of the tread portion. A groove is formed.

  In this way, in the first aspect of the invention, since a part of the rubber material constituting the surface portion of the tread portion is ground, the grinding waste generated by this grinding is easily removed from the groove. Therefore, since there is no restriction on the shape of the groove, the degree of freedom in designing the groove pattern can be improved, and the groove can be formed efficiently.

  As the grinding, grinder grinding or drill grinding may be performed, and the grinding method is not particularly limited. When high finishing accuracy is required, grinding may be performed using a lubricant.

  The invention according to claim 1 can be applied regardless of whether the groove formed in the tread portion is a thick groove or a thin groove.

  The invention according to claim 2 is characterized in that the groove is formed along the tire circumferential direction by rotating the tire around the tire rotation axis while rotating and contacting the grinder to the tread portion. To do.

  Thereby, the groove | channel along a tire peripheral direction can be formed easily in a short time. In addition, after grinding with the grinder for groove formation, you may make the external appearance of a product tire favorable by grind | polishing with the grinder for surface finishing.

  The invention according to claim 3 is characterized in that the groove is formed along the tire circumferential direction by rotating a drill around the tread portion and rotating the tire around a tire rotation axis. To do.

  Thereby, the groove | channel along a tire peripheral direction can be easily formed in a short time like the invention of Claim 2.

  The invention according to claim 4 is an apparatus for forming a groove in a tread portion of a tire after vulcanization molding, wherein the tire is detachably attached and the attached tire is rotated around a tire rotation axis. And rotating means for contacting the tread portion of the tire attached to the rotating means, and grinding means for grinding a part of the rubber material constituting the surface portion of the tread portion. The groove along the groove is formed in the tread portion.

  In the invention according to claim 4, the grinding means is brought into contact with the tread portion while rotating the tire, and a part of the rubber material constituting the surface portion of the tread portion is ground. The grinding debris to be removed is easily removed from the groove. Therefore, according to the invention described in claim 4, it is possible to realize a tire groove forming apparatus capable of improving the design freedom of the groove pattern and efficiently forming the groove.

  The invention described in claim 5 is characterized in that a grinder capable of coming into contact with and separating from the tread portion of the tire attached to the rotating means is provided as the grinding means.

  Thereby, the structure of a grinding means can be simplified.

  The invention according to claim 6 is characterized in that a drill capable of contacting and separating is provided as the grinding means on the tread portion of the tire attached to the rotating means.

  Thereby, the structure of a grinding means can be simplified like the invention of Claim 5.

  The invention described in claim 7 is characterized in that the drill is attached so as to be movable in the tire width direction.

  Accordingly, grooves extending in the tire width direction can be formed. For example, grooves extending in a zigzag shape in the tire circumferential direction and grooves extending in a zigzag shape in the tire circumferential direction can be easily formed in a short time. .

  Note that extending in a zigzag manner in the tire circumferential direction means that a groove portion extending in the same direction as the tire circumferential direction and a groove portion extending obliquely with respect to the tire circumferential direction are alternated and extend in the tire circumferential direction. It means that the groove portions extending in the same direction as the circumferential direction are arranged in a staggered manner. The phrase “zigzag extending in the tire circumferential direction” means that the groove portions that are inclined with respect to the tire circumferential direction extend in the tire circumferential direction while turning back so that the inclination directions are alternate.

  Since the present invention has the above-described configuration, it is possible to improve the design freedom of the groove pattern and to efficiently form the groove.

  Hereinafter, embodiments will be described and embodiments of the present invention will be described. In the second and subsequent embodiments, the same components as those already described are denoted by the same reference numerals and description thereof is omitted.

[First Embodiment]
First, the first embodiment will be described. As shown in FIG. 1, in the present embodiment, circumferential grooves 18 (FIG. 3, FIG. 3) along a tire circumferential direction U are formed on a tread portion 16 of a large pneumatic tire 10 such as an ORR (hereinafter simply referred to as a tire 10). The tire groove forming device 20 is used to form the tire groove (see FIG. 4). The circumferential groove 18 is narrow and deep.

  The tire groove forming device 20 abuts on the tread portion 16 of the tire 10 attached to the rotary shaft 22 and the tread portion 16 of the tire 10 attached to the rotary shaft 22. The grinder type grinding part 26 which grinds a part of rubber material which comprises the surface part 17 of this, and the raising / lowering mechanism 30 which raises / lowers the grinder type grinding part 26 are provided. In the present embodiment, the elevating mechanism 30 can adjust the position in the tire width direction of the grinder-type grinding part 26 to an arbitrary position, whereby the grinder 32 constituting the grinder-type grinding part 26 can be adjusted. The position in the tread width direction can be adjusted.

  The rotation shaft 22 of the rotation drive unit 24 can be rotated by a motor (not shown). The structure of the rotation drive unit 24 is such that the tire 10 is attached so that the rotation shaft 22 and the tire rotation axis of the tire 10 to be attached coincide with each other.

  The grinder 32 has a thin and uniform disk shape, and the outer peripheral surface is a grinding surface 33. The width of the grinding surface 33 is set so that the value obtained by adding this width and the width of the cutting margin is the same as the width of the circumferential groove 18.

  The grinder type grinding unit 26 is provided above the rotation driving unit 24. The grinder type grinding part 26 is attached to the lifting mechanism 30 so that the grinding surface 33 of the grinder 32 faces the surface part 17 of the tread part 16 of the tire 10 attached to the rotation drive part 24.

  Hereinafter, an operation of forming a circumferential groove in the pneumatic tire 10 by the tire groove forming device 20 will be described.

  First, the vulcanized tire 10 is attached to the rotation shaft 22 of the rotation drive unit 24.

  Then, with the rotation of the tire 10 stopped, the grinder 32 is rotated, and the grinder type grinding unit 26 is lowered by the lifting mechanism 30.

  As a result, the grinding surface 33 of the grinder 32 comes into contact with the surface portion 17 of the tread portion 16, and grinding of the surface portion 17 is started.

  When the height of the grinder 32 reaches a set height, that is, a height at which a predetermined groove depth is formed, the descent of the grinder-type grinding unit 26 by the elevating mechanism 30 is stopped.

  And the surface part 17 is ground in the tire circumferential direction U by the grinder 32 by rotating the tire 10 by the rotational drive part 24 at a comparatively low fixed speed (refer FIG. 2). The rotational speed of the rotational drive unit 24 is set to a speed that does not hinder grinding with the grinder 32.

  As a result, the circumferential groove 18 is formed by the grinder 32 (see FIGS. 3 and 4). Since the grinding waste generated by grinding is fine, it is easily released from the circumferential groove 18 by the rotation of the grinder 32 during grinding. The groove side wall 19 of the circumferential groove 18 formed in this way is not tapered, and the angle formed between the groove side wall 19 and the tire radial direction is 0 °.

  As described above, in the present embodiment, the circumferential groove 18 is formed by grinding the grinder 32 in contact with the tread portion 16. Therefore, since the grinding waste is fine-grained, the grinding waste can be easily detached from the circumferential groove 18 without forming a taper on the groove side wall 19. Moreover, since the height of the grinder 32 at the time of grinding can be adjusted to an arbitrary height by the elevating mechanism 30, even a deep groove can be easily formed.

  Thereby, while being able to improve the design freedom of the pattern of the circumferential groove | channel 18, the circumferential groove | channel 18 can be formed efficiently.

  In this embodiment, after stopping the lowering of the grinder 32, the tire 10 is rotated. However, the grinder 32 is lowered while rotating the tire 10, and the grinder 32 is lowered when the height of the grinder 32 reaches a set height. May be stopped.

[Second Embodiment]
Next, a second embodiment will be described. As shown in FIG. 5, in the present embodiment, a tire groove forming device having a drill type grinding part with a drill 42 attached to the tip is used instead of the grinder type grinding part 26 as compared with the first embodiment. This drill-type grinding part is attached to an elevating mechanism 30 (see FIG. 1). A grindstone is preferably disposed on the side wall of the drill 42. The diameter of the drill 42 is a diameter corresponding to the width of the groove to be formed.

  In the present embodiment, the elevating mechanism 42 can adjust the position in the tire width direction of the drill-type grinding part to an arbitrary position, whereby the tread width of the drill 42 constituting the drill-type grinding part. The direction position can be adjusted.

  In the present embodiment, first, similarly to the first embodiment, the vulcanized tire 10 is attached to the rotation shaft 22 of the rotation drive unit 24.

  Then, in a state where the rotation of the tire 10 is stopped, the drill 42 is rotated and the drill-type grinding unit is lowered by the lifting mechanism 30.

  As a result, the tip of the drill 42 comes into contact with the surface portion 17 of the tread portion 16, and the surface portion 17 is shaved in the depth direction by the drill 42.

  When the height of the tip of the drill 42 reaches a set height, that is, a height at which a predetermined groove depth is formed, the lowering of the drill type grinding unit by the lifting mechanism 30 is stopped.

  And the surface part 17 is ground in the tire circumferential direction U by the drill 42 by rotating the tire 10 at a relatively low constant speed by the rotation drive unit 24 (see FIG. 5). The rotational speed of the rotational drive unit 24 is set to a speed that does not hinder grinding with the drill 42 as in the first embodiment.

  At this time, in this embodiment, the drill-type grinding part is reciprocated in the tire width direction W.

  As a result, a zigzag groove 48 extending in a zigzag shape in the tire circumferential direction U is formed by the drill 42 (see FIG. 6). Since grinding waste generated by grinding is sent out of the tire along the drill 42, it is easily released from the zigzag groove 48 by the rotation of the drill 42 during grinding. The groove side wall 49 of the zigzag groove 48 formed in this way is not tapered, and the angle formed between the groove side wall 49 and the tire radial direction is 0 °.

  As described above, in this embodiment, the zigzag groove 48 is formed by grinding the drill 42 in contact with the tread portion 16. Accordingly, since the grinding waste is fed out of the tire along the drill 42, the grinding waste can be easily detached from the zigzag groove 48 without forming a taper on the groove side wall 49. Further, since the height of the drill 42 at the time of grinding can be adjusted to an arbitrary height by the elevating mechanism 30, even a deep groove can be easily formed. Thereby, the design freedom of the groove pattern along the tire circumferential direction U can be improved, and the groove can be formed efficiently.

  Even if a tire groove forming device is not used, a general-purpose drill type processing device is used, and as shown in FIG. 7, a cylindrical hole 57 is sequentially formed so as to be continuous in the tire circumferential direction U. A groove 58 may be formed.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. Needless to say, the scope of rights of the present invention is not limited to the above embodiment.

It is a side view showing composition of a tire groove forming device concerning a 1st embodiment. It is side surface sectional drawing which shows forming a groove | channel in 1st Embodiment. It is a fragmentary top view which shows the circumferential groove | channel formed in 1st Embodiment. It is a tire radial direction fragmentary sectional view which shows the circumferential groove | channel formed in 1st Embodiment. It is side surface sectional drawing which shows forming a groove | channel in 2nd Embodiment. It is a fragmentary top view which shows the circumferential groove | channel formed in 2nd Embodiment. In 2nd Embodiment, it is a fragmentary top view which shows forming a circumferential direction groove | channel by another method. It is a perspective view which shows the cutter which grooves the tread part of the tire after a vulcanization molding with the conventional tire manufacturing method. It is a tire radial direction fragmentary sectional view which shows that cutting waste is removed from a groove | channel with the cutter shown in FIG. It is a tire radial direction fragmentary sectional view which shows that the cutting waste is hard to be removed from a narrow groove with the conventional tire manufacturing method.

Explanation of symbols

10 Tire 16 Tread portion 17 Surface portion 18 Circumferential groove (groove)
20 Tire groove forming device 24 Rotation drive unit (rotating means)
32 Grinder 42 Drill 48 Zigzag groove (groove)
58 Circumferential groove (groove)
88 Thick groove
98 Narrow groove (groove)

Claims (7)

A tire manufacturing method for forming a groove in a tread portion of a tire after vulcanization molding,
The tire manufacturing method, wherein the groove is formed by grinding a part of a rubber material constituting a surface portion of the tread portion.   2. The tire manufacturing method according to claim 1, wherein the groove is formed along a tire circumferential direction by rotating a grinder on the tread portion and bringing the tire into contact with the tread portion and rotating the tire around a tire rotation axis. Method.   2. The tire manufacturing method according to claim 1, wherein the groove is formed along a tire circumferential direction by rotating a drill into contact with the tread portion and rotating the tire around a tire rotation axis. Method. An apparatus for forming a groove in a tread portion of a tire after vulcanization molding,
A rotating means for detachably attaching the tire and rotating the attached tire around a tire rotation axis;
A grinding means for abutting the tread portion of the tire attached to the rotating means and grinding a part of a rubber material constituting the surface portion of the tread portion;
A tire groove forming apparatus, wherein the groove along the tire circumferential direction is formed in the tread portion.   The pneumatic tire groove forming device according to claim 4, wherein a grinder capable of coming into contact with and separating from the tread portion of the tire attached to the rotating means is provided as the grinding means.   The pneumatic tire groove forming apparatus according to claim 4, wherein a drill capable of contacting and separating from the tread portion of the tire attached to the rotating means is provided as the grinding means.   The tire groove forming apparatus according to claim 6, wherein the drill is attached so as to be movable in a tire width direction.

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