JP6238708B2 - Pneumatic tire and manufacturing method thereof - Google Patents

Description

  The present invention relates to a pneumatic tire and a method for manufacturing the same.

Conventionally, as Patent Document 1, a tire belt (reinforcing member) having a configuration in which another wire coil is wound from two directions intersecting with a plurality of wire coils arranged in parallel in the longitudinal direction is known. .
Patent Document 2 discloses a tire belt having a configuration in which a plurality of belt cords extending in three intersecting directions are woven together.
Patent Document 3 discloses a tire belt made of a thin metal plate having a mesh structure.

However, in patent document 1, since only the other wire coil which cross | intersects the wire coil extended in a longitudinal direction is tangled, there is a possibility that it may rub against each other and wear and may break depending on the case. In particular, when a resin material is used for the wire coil for weight reduction, this problem becomes remarkable.
In Patent Document 2, as in the case of Patent Document 1, the belt cords are slidably contacted with each other and worn, and in some cases, the belt cord may be broken.
Moreover, in patent document 3, since the whole is comprised with the single thin metal material, there exists a possibility that it may fracture | rupture, when an external force concentrates on the part when the built-in tires run on a curbstone.
In any of the above-mentioned patent documents, there is no description regarding a configuration for reducing the weight of the chafer and improving the durability.

JP-A-1-237203 JP-A-5-162508 JP 2000-25412 A

  This invention makes it a subject to provide the pneumatic tire provided with the chafer which was lightweight and excellent in durability, and its manufacturing method.

As a means for solving the above problems, the present invention provides:
A pneumatic tire having a chafer disposed outside a carcass ply folded from the inside to the outside with a bead core,
The chafer is
A substrate including a plurality of wires arranged to extend in a specific direction at intervals,
The base material includes a plurality of polygonal portions repeatedly formed in two dimensions,
Each polygonal part is defined by a threaded part and a single line part;
Each of the threaded portions is formed by twisting two or more wires arranged adjacent to each other among the wires,
Each said single wire part provides the pneumatic tire which is one side of the wire which comprises the said screwing part.

  With this configuration, it is possible to effectively prevent the positional deviation between the wires at the screwed portion formed by twisting the wires twice or more. Therefore, it is possible to greatly reduce the possibility that the wires are rubbed and broken due to wear. In addition, the polygonal portion can increase multidirectional rigidity. Furthermore, since the polygonal part is merely formed continuously on the same plane, it is not necessary to make it multi-layered, and the weight can be reduced. In other words, the weight can be reduced while maintaining the durability of the chafer.

  In the chafer, it is preferable that the position of the outer end of the bead core is located on the tire outer diameter side with respect to the position of the inner end of the bead core.

  With this configuration, when the tire is mounted on the rim flange on the vehicle side, rim displacement can be prevented by increasing the frictional resistance by increasing the contact area between the chafer and the rim flange.

  In the chafer, the position of the outer end of the bead core is preferably positioned closer to the tire outer diameter side than the position of the outer diameter end of the rim flange to which the pneumatic tire is mounted.

  With this configuration, it is possible to further reduce the occurrence of rim displacement in the chafer mounted state on the rim flange.

  For example, in the chafer, the position of the outer end of the bead core may be in the range of 50 to 70% with respect to the height dimension of the bead filler that is disposed on the outer diameter side adjacent to the bead core.

  The chafer preferably forms a winding side region densely as compared with a winding side region with respect to the bead core.

  With this configuration, it is possible to more appropriately prevent rim displacement while suppressing an increase in the weight of the chafer.

  In this case, it is preferable that the tightly formed winding side region of the chafer is at least a contact portion with the rim.

  It is preferable that the chafer is formed of a vertical wire material in which the base material has a strip shape and both side portions extend in the longitudinal direction.

  With this configuration, it is easy to maintain the chafer in a stable shape with the vertical wires on both sides of the base material, and the rigidity balance can be improved.

  In the chafer, it is preferable that the base material includes three or more vertical wire rods, and a plurality of polygonal portions are formed in each divided region between the vertical wire rods.

  With this configuration, the rigidity in each divided region can be changed so as to be appropriate for the chafer.

The chafer is preferably the shape of each polygonal portion constituting the base material that has different.

  With this configuration, even if the required rigidity has directionality, it can be dealt with by changing the shape of the polygonal portion accordingly. For example, it may be formed so as to be short in a direction where rigidity is required and long in a direction where rigidity is not required.

  The chafer is preferably formed by arranging polygonal portions having different shapes between the divided regions.

  With this configuration, the level of rigidity in each divided region can be set to a value suitable for the chafer.

  The chafer is only required to adjust the shape of the polygonal part by changing the pitch of the threaded part.

  The chafer is not limited as long as the pitch of the threaded portions can be adjusted by changing the number of times of twisting between the wires, the inclination angle of the single wire extending from the threaded portions, or the interval between adjacent wires.

What is necessary is just to make it the said chafer further provide the coating | coated part which coats the whole said base material.
The polygonal part may be a quadrangle or a hexagon.

As a means for solving the above problems, the present invention provides:
A pneumatic tire having a chafer disposed outside a carcass ply folded from the inside to the outside with a bead core,
The chafer is
A threaded portion formed by twisting wires together;
A single wire portion formed from one of the wires extending from the threaded portion;
Comprising a base material formed by continuously forming a polygonal part surrounded by the same plane,
The threaded portion of the base material is formed by twisting two wire materials two or more times.

  With this configuration, it is possible to effectively prevent the positional deviation between the wires at the screwed portion formed by twisting the wires twice or more. Therefore, it is possible to greatly reduce the possibility that the wires are rubbed and broken due to wear. In addition, the polygonal portion can increase multidirectional rigidity. Furthermore, since the polygonal part is merely formed continuously on the same plane, it is not necessary to make it multi-layered, and the weight can be reduced. In other words, the weight can be reduced while maintaining the durability of the chafer.

  According to the present invention, a tire chafer is provided with a base material composed of a plurality of polygonal parts surrounded by a threaded part and a single wire part, and the twisted part is twisted two times or more between two wire rods. Because of this configuration, there is almost no friction between the wires, and there is no fear of cutting due to wear. Therefore, the durability of the chafer can be improved, and desired performance can be exhibited over a long period of time, and the weight can be reduced.

It is a fragmentary sectional view in the meridian surface of the pneumatic tire concerning this embodiment. It is a perspective view of the chafer of FIG. It is a top view of the base material shown in FIG. It is an enlarged view of one polygon part shown in FIG. It is a top view of the base material which shows the modification of FIG. It is a top view of the base material which shows the modification of FIG. It is a top view of the base material which shows the modification of FIG. It is a top view of the base material which shows the modification of FIG. It is a top view which shows the base material of the chafer which concerns on other embodiment. It is a top view which shows the base material of the chafer which concerns on other embodiment.

  Embodiments according to the present invention will be described below with reference to the accompanying drawings. In addition, the following description is only illustrations essentially and does not intend restrict | limiting this invention, its application thing, or its use. In the drawings, the same or similar parts are denoted by the same or similar reference numerals. The drawings are schematic and ratios of dimensions and the like are different from actual ones.

  FIG. 1 is a partial cross-sectional view of a pneumatic tire according to this embodiment. In this pneumatic tire, the external structure includes a tread portion 1, a shoulder portion 2, a side portion 3 and a bead portion 4. The internal structure includes a belt 5 provided from the tread portion 1 to the shoulder portion 2. A reinforcement ply 6 is provided on the outer peripheral side of the belt 5. A carcass ply 7 is provided on the inner peripheral side of the belt 5. The carcass ply 7 is directed from the tread portion 1 to the bead portion 4, folded back by a bead core 8 incorporated therein, and reaches the outer surface side beyond the bead filler 9 adjacent thereto. The folded portion of the carcass ply 7 is reinforced by the chafer 10. Note that description of other members is omitted here.

  The chafer 10 is a sheet formed by covering the surface of the base material 11 with the covering portion 12, and covers the folded portion of the bead core 8 on the outer surface side of the carcass ply 7 within a predetermined range from the inside to the outside. To be pasted. The folded portion of the chafer 10 is a winding region 10A on the inner side (left side region in FIG. 1) than the center position of the inner diameter portion of the bead core 8, and the outer side (right side region in FIG. 1) is a winding region 10B. is there.

  The outer end position 10a of the chafer 10 is disposed closer to the tire outer diameter (upward in the drawing) than the inner end position 10b. Specifically, the outer end position 10 a of the chafer 10 is provided in a range of 50 to 75% of the height dimension (the length in the tire radial direction) of the bead filler 9. On the other hand, the inner end position 10b of the chafer 10 is provided in a range of 20 to 50% of the height dimension of the bead filler 9 (the length in the tire radial direction).

  Further, the outer end position 10a of the chafer 10 may be determined as follows because the height dimension of the bead filler 9 (the length in the tire radial direction) varies depending on the type of tire. That is, in the tire cross section, from the inner diameter portion of the bead core 8 (the position of the nominal diameter of the bead core 8 (including the carcass ply 7 and the chafer 10): the reference position A) toward the tire outer diameter direction (18.0). The outer end position 10a of the chafer 10 may be determined so as to have a height of ± 8.0) mm (in this case, the height (in the tire outer diameter direction) of the rim flange 14 from the reference position A) Is 17.5 mm).

  Here, two types of methods for determining the outer end position 10a of the chafer 10 have been introduced. However, the outer end position 10a of the chafer 10 has a tire attached to the rim flange 14 with the tire mounted on the rim 13. It may be determined only to project to the outer diameter side. Further, the inner end position 10b of the chafer 10 may be inside the bead core 8 (inside the position indicated by the point 8a of the inner diameter portion of the bead core 8 in FIG. 1).

  Thus, by setting the position of the chafer 10 (outer end position 10a and inner end position 10b), the contact area between the chafer 10 and the rim flange 14 when the tire is mounted on the rim 13 on the vehicle side. Can be increased, and rim displacement can be prevented.

  As shown in FIG. 3, the base material 11 is a sheet-like material in which a plurality of wire portions 15 are twisted together at a predetermined position to form a plurality of polygonal portions 16.

  For the wire 15, a metal material such as steel, a resin material made of organic fibers such as polyester, aramid, rayon, nylon, or the like can be used. Each wire 15 may be composed of a single wire, but a plurality of thinner wires may be bundled or twisted to form a single wire.

  The base material 11 is formed by arranging a plurality of one wire 15 in the vertical direction (longitudinal direction) and twisting adjacent wires at a predetermined pitch in the vertical direction. That is, a polygonal portion 16 surrounded by a threaded portion 17 in which adjacent wire rods are twisted together and a single wire portion 18 composed of one wire rod 15 extending from the threaded portion 17 is formed. Here, the polygon part 16 is comprised by the regular hexagon. Further, the screwing portion 17 is formed by twisting the wire materials two or more times. Here, the threaded portion 17 is formed by twisting the wire rods twice and a half (in FIG. 2, a circular space is shown at the center position of the threaded portion 17. This is to make the state easy to understand, and no space is actually formed.) The wire 15 (vertical wire 19) on both sides is used while extending straight in the vertical direction. The polygonal portion 16 is continuously formed on the same plane between the vertical wire rods 19 and constitutes a honeycomb form.

  As shown in FIG. 4, the description will be made in detail with a focus on one polygonal portion 16. The polygonal portion 16 includes a first single wire portion 18A composed of a first wire rod 15A extending from a threaded portion 17 obtained by twisting two adjacent wire rods 15 and a second single wire composed of a second wire rod 15B. Part 18B. Further, the first wire rod 15A and a first screw portion 17A in which the third wire rod 15C adjacent to the first wire rod 15A on the opposite side to the second wire rod 15B is twisted. Further, the second wire rod 15B and a second screw portion 17B in which the fourth wire rod 15D adjacent to the second wire rod 15B on the opposite side of the first wire rod 15A is twisted. Furthermore, it has the 3rd single wire part 18C which consists of the 1st wire 15A branched from the 17th screw part 17A, and the 4th single wire part 18D which consists of the 2nd wire 15B branched from the 2nd screw part 15B. The third single wire portion 18C (first wire rod 15A) and the fourth single wire portion 18D (second wire rod 15B) are twisted together to form the screwed portion 17.

  The shape of the polygonal portion 16 can be changed to a vertically long shape or a horizontally long shape by changing the threaded portion pitch, that is, the honeycomb density. Here, as shown in FIG. 3, the threaded portion pitch is a vertical pitch P <b> 1 that is a distance between the longitudinally threaded portions 17 (here, a central position is used), and a laterally threaded portion 17. Means a horizontal pitch P2.

  The adjustment of the vertical pitch P1 can be performed by increasing / decreasing the number of times the screwing portion 17 is screwed or by adjusting the inclination angle θ of the single wire portion 18.

  As the number of times of screwing of the threaded portion 17 is increased, it is possible to prevent the positional displacement between the wire rods and to make it difficult to rub, but as described above, it is possible to sufficiently prevent the friction between the wire rods during use. That is all you need. By adjusting the number of times of screwing, the length of the screwing part 17 can be changed to adjust the vertical pitch P1. For example, as shown in FIG. 7, each regular hexagon can be made into a vertically long shape by increasing the number of times of screwing, or it can be made into a horizontally long shape (not shown) by reducing the number of times of screwing. it can.

  The vertical pitch P1 can also be adjusted by changing the inclination angle of the single wire portion 18 extending from the threaded portion 17 (inclination angle θ of the single wire portion 18 with respect to the vertical direction (vertical direction) in FIG. 3). In FIG. 5, the inclination angle with respect to the threaded portion 17, that is, the inclination angle θ with respect to the vertical direction is increased to form a horizontally long shape. In FIG. 6, the inclination angle with respect to the threaded portion 17, that is, the inclination angle θ with respect to the vertical direction is reduced to form a vertically long shape.

  The adjustment of the lateral pitch P2 can be performed by adjusting the interval of the wire 15. That is, the polygonal portion 16 can be made horizontally long by widening the interval between the wire rods 15 and can be made vertically long by narrowing.

  In this way, the regular hexagon can be adjusted to either a vertically long shape or a horizontally long shape by increasing / decreasing the number of times of screwing of the screwing portion 17 and adjusting the inclination angle θ of the single wire portion 18. By adopting a vertically long shape, the rigidity in the vertical direction can be reduced compared to the horizontal direction. On the other hand, by adopting a horizontally long shape, the rigidity in the horizontal direction can be reduced compared to the vertical direction.

  Further, the shape of the polygonal portion 16 of the base material 11 is not limited to a hexagon (including a regular hexagon and a vertically long or a horizontally long hexagon), and may be a quadrangle shown in FIG. That is, by making the length of the single wire portion 18 sufficiently larger than the screwed portion 17, it can be made a quadrangular shape. In FIG. 8, the polygonal portion 16 has a rhombus shape.

  The base material 11 having the above-described structure becomes the chafer 10 by coating with a thin rubber (topping rubber) (not shown) or by coating a film-like synthetic resin by thermal welding. .

  The chafer 10 having the above-described configuration is attached to the folded portion of the carcass ply 7 so that the vertical wires 19 on both sides are along the tire circumferential direction. In a tire provided with such a chafer 10, the twisted portions 17 between the wires are twisted together at a number of times of two or more, so that the wires are not rubbed in use (running by the tire). . Therefore, there is no fear that the wire 15 is damaged due to wear and cut.

[Example]
An actual vehicle feeling test was performed using the pneumatic tire including the belt 5 of the comparative example and the pneumatic tire including the belt 5 of the example according to the present invention. For more information, in the size 195 / 65R15 91H, air pressure using a pneumatic tire of 180kPa, they were evaluated for re-time the amount of deviation.
The Trim shift amount, less deviation amount is more indices is small, the better the performance.

比較例１：従来構造のナイロン製のチェーファー１０を使用したタイヤ
比較例２：線材１５の捩合回数を１回としたチェーファー１０を使用したタイヤ
実施例１：線材１５の捩合回数を２回としたチェーファー１０を使用したタイヤ（多角形部１６の密度は、内側と外側で同じ）
実施例２：線材１５の捩合回数を２回としたチェーファー１０を使用したタイヤ（多角形部１６の密度は、内側の方が外側よりも大きい）
実施例３：線材１５の捩合回数を２回としたチェーファー１０を使用したタイヤ（多角形部１６の密度は、外側側の方が内側よりも大きい）

Comparative example 1: Tire using nylon chafer 10 having a conventional structure Comparative example 2: Tire using chafer 10 in which the number of times of twisting of wire 15 is one Example 1: Number of times of twisting of wire 15 Tire using the chafer 10 that has been made twice (the density of the polygonal portion 16 is the same on the inside and outside)
Example 2: Tire using the chafer 10 in which the wire 15 is twisted twice (the density of the polygonal portion 16 is larger on the inside than on the outside).
Example 3: Tire using the chafer 10 in which the wire 15 is twisted twice (the density of the polygonal portion 16 is larger on the outer side than on the inner side).

As apparent from Table 1, by the constitution of any of Examples 1-3, it is possible to sufficiently suppress the Trim shift amount, the third embodiment in particular to increase the density of the polygonal portion 16 outside the The effect could be exhibited remarkably.

  In addition, this invention is not limited to the structure described in the said embodiment, A various change is possible.

  For example, in the above embodiment, the chafer 10 is composed of one layer, but it may be composed of two or more layers.

  Moreover, in the said embodiment, although the base material 11 was formed by twisting together the several wire 15 arranged in parallel in the horizontal direction in the predetermined position of the vertical direction between adjacent wires, the diagonal which cross | intersects mutually The base material 11 may be formed by twisting together the wires extending in the direction.

  Further, as shown in FIG. 9, by providing three vertical wires 17, a configuration having two divided areas (first divided area 20 and second divided area 21) is formed, and each divided area 20, 21 has a polygonal shape. The density and rigidity may be varied by changing the shape and size of the portion 16. In this case, it is preferable that the winding region 10B is dense and the winding region 10A is sparse. By making the winding region 10B dense, the frictional resistance with the rim flange 14 can be increased, and rim displacement can be prevented more effectively. Moreover, the vibration transmitted from the road surface to the rim 13 via the tire can be reduced by making the winding region 10A sparser than the winding region 10B.

  Further, as shown in FIG. 10, by providing three vertical wires 17, the structure has three divided regions (first divided region 20, second divided region 21, and third divided region 22), and the same as described above. Thus, the density and rigidity of the polygonal portion 16 may be made different between the divided regions 20, 21, and 22.

  Further, the number of divided areas is not limited to the number of examples, and the number of divided areas can be freely changed according to the application.

  Furthermore, although the polygonal part 16 of each divided region is all configured with a hexagon, it may be configured with another polygon such as a quadrangle as in the above embodiment. Further, the polygonal shape may be different in each divided region. For example, the polygonal portion 16 may be a hexagon in the first divided region and a quadrangle in the second region. Moreover, the length of the screwing part 17 formed in the vertical wire rod of the boundary part may not be the same, and the position may be shifted in the vertical direction. This is the same regardless of the shape of the polygonal portion 16.

DESCRIPTION OF SYMBOLS 1 ... Tread part 2 ... Shoulder part 3 ... Side part 4 ... Bead part 5 ... Belt 6 ... Reinforcement ply 7 ... Carcass ply 8 ... Bead core 9 ... Bead filler 10 ... Chafer 11 ... Base material 12 ... Covering part 13 ... Rim 14 ... Rim flange 15 ... Wire material 16 ... Polygonal portion 17 ... Screw portion 18 ... Single wire portion 19 ... Vertical wire material 20 ... First divided region 21 ... Second divided region 22 ... Third divided region

Claims (17)

A pneumatic tire having a chafer disposed outside a carcass ply folded from the inside to the outside with a bead core,
The chafer is
A substrate including a plurality of wires arranged to extend in a specific direction at intervals,
The base material includes a plurality of polygonal portions repeatedly formed in two dimensions,
Each polygonal part is defined by a threaded part and a single line part;
Each of the threaded portions is formed by twisting two or more wires arranged adjacent to each other among the wires,
Each said single wire part is one side of the wire which comprises the said screwing part, The pneumatic tire characterized by the above-mentioned.   2. The pneumatic tire according to claim 1, wherein a position of an outer end of the bead core is positioned on an outer diameter side with respect to a position of an inner end of the bead core.   The position of the outer end of the bead core is positioned on the tire outer diameter side of the chafer from the position of the outer diameter end of the rim flange to which the pneumatic tire is mounted. Pneumatic tire.   The chafer is characterized in that the position of the outer end of the bead core is in the range of 50 to 70% with respect to the height dimension of the bead filler disposed adjacent to the bead core toward the tire outer diameter side. The pneumatic tire according to any one of claims 1 to 3.   The pneumatic tire according to any one of claims 1 to 4, wherein the chafer has a winding side region formed denser than a winding side region with respect to the bead core.   The pneumatic tire according to claim 5, wherein the chafer has a tightly formed winding side region at least a contact portion with a rim.   The pneumatic tire according to any one of claims 1 to 6, wherein each of the chafers is formed of a vertical wire rod in which the base material has a strip shape and both side portions extend in the longitudinal direction.   8. The chafer according to claim 7, wherein the base material includes three or more vertical wires, and a plurality of polygonal portions are formed in each divided region between the vertical wires. The described pneumatic tire. The chafer pneumatic tire according to any one of claims 1 to 8, the shape of the polygonal portion constituting said substrate is that you have different.   The pneumatic tire according to claim 9, which is dependent on claim 8, wherein the chafer is formed by arranging polygonal portions having different shapes between the divided regions.   The pneumatic tire according to claim 9 or 10, wherein the chafer can be adjusted by changing a shape of the polygonal portion by changing a pitch of a screwed portion.   The chafer is characterized in that the pitch of the threaded portion can be adjusted by changing the number of times of twisting between the wires, the inclination angle of the single wire extending from the threaded portion, or the interval between adjacent wires. The pneumatic tire according to claim 11.   The pneumatic tire according to any one of claims 1 to 12, wherein the chafer further includes a covering portion that coats the entire base material. The pneumatic tire according to claim 1, wherein the polygonal portion is a quadrangle or a hexagon. A pneumatic tire having a chafer disposed outside a carcass ply folded from the inside to the outside with a bead core,
The chafer is
A threaded portion formed by twisting wires together;
A single wire portion formed from one of the wires extending from the threaded portion;
Comprising a base material formed by continuously forming a polygonal part surrounded by the same plane,
The pneumatic tire according to claim 1, wherein the threaded portion of the base material is formed by twisting two wire rods two or more times. A polygonal portion surrounded by a twisted portion formed by twisting wires together two or more times and a single wire portion extending from the screwed portion and made of one of the wires is continuously formed on the same plane. The manufacturing method of the pneumatic tire characterized by including the formation process of the chafer provided with the base material to perform. Furthermore, the manufacturing method of the pneumatic tire of Claim 16 provided with the formation process of the belt which coats the whole said base material with a coating | coated part.

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