JP2011026710A - Cord fabric and pneumatic tire using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a producing method, by which can be obtained the pneumatic tire 8 having a high quality and in excellent productivity. <P>SOLUTION: The cord fabric 48 for tires used in the producing method, comprises main cord groups MG comprising a plurality of parallel main cords 42a and dummy cord groups DG comprising a plurality of parallel dummy cords 42b. The main cord groups MG and the dummy cord groups DG are alternately arranged. The intermediate elongations of the dummy cords 42b are larger than those of the main cords 42a. Preferably, the ratio of the intermediate elongations of the dummy cords 42b to the intermediate elongations of the main cords 42a is 150-250%. Preferably, the number of the dummy cords 42b contained in each dummy cord group DG is 2-4. Preferably, the number of the main cords 42a contained in each main cord group MG is 5-15. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pneumatic tire. In particular, the present invention relates to a pneumatic tire provided with a band formed using a weave fabric.

  The pneumatic tire has a band inside the tread in the radial direction. This band includes a cord wound spirally in the circumferential direction. Such a band structure is called a jointless structure. For the formation of this band, a strip in which 3 to 20 cords are arranged in parallel is used.

  FIG. 6 is a cross-sectional perspective view showing a part of the strip 2 used for forming a band of a pneumatic tire. The strip 2 includes ten cords 4 arranged in parallel and a topping rubber 6. These codes 4 are arranged at equal intervals. Each cord 4 extends in the direction indicated by the double arrow A. In this tire manufacturing method, the strip 2 is spirally wound in the circumferential direction to form a band.

  The strip 2 is formed as follows. Although not shown, a cord fabric is formed in which 1000 to 2000 cords 4 are juxtaposed and the positions of these cords 4 are held by wefts. A sheet made of topping rubber 6 is bonded to this interwoven fabric to form a ply. This ply is cut and the strip 2 is obtained. An example of a method for manufacturing a tire using a weave fabric is disclosed in Japanese Patent Application Laid-Open No. 2006-239938. In this publication, a carcass ply is formed using a braided fabric.

  Although not shown, the strip 2 is formed using a cutting jig provided with a plurality of knives and these knives arranged at predetermined intervals. This interval is adjusted in consideration of the number of cords 4 included in the formed strip 2. By using this cutting jig, a large number of strips 2 are formed by one slit.

JP 2006-239938 A

  The topping rubber 6 constituting the ply contains carbon black. The topping rubber 6 is black. The cord 4 is covered with this topping rubber 6. For this reason, the position of the cord 4 cannot be specified from the appearance of the ply.

  In this manufacturing method, even if the knives are placed at equal intervals, the number of cords 4 included in the obtained strip 2 may vary due to variations in the spacing of the cords 4. In order to accurately measure the number of the cords 4, it is necessary to disassemble the end portion of the ply and confirm the position of the cord 4. This work takes time. This operation hinders productivity.

  In the ply formed using the interwoven fabric, the position of the cord 4 in the width direction may be shifted. Since the position of the cord 4 cannot be grasped when the ply is cut with the cutting jig, the cord 4 is cut if the cord 4 exists in the moving direction of the knife. The cutting of the cord 4 causes variations in the number of cords 4 included in the strip 2. This variation affects the tire quality. In particular, in consideration of productivity, when the right side portion of the band is formed by using one strip 2 and the left side portion of the band is formed by using another strip 2, the above variation causes the binding force of the band. May affect. In this case, the tire conicity is deteriorated.

  An object of the present invention is to provide a production method capable of obtaining a pneumatic tire having excellent productivity and high quality.

  The tire weave fabric according to the present invention includes a main cord group including a plurality of main cords arranged in parallel and a dummy cord group including a plurality of dummy cords arranged in parallel. The main code group and the dummy code group are arranged alternately. The intermediate elongation of the dummy cord is larger than the intermediate elongation of the main cord.

  Preferably, in the tire weave fabric, the ratio of the intermediate elongation of the dummy cord to the intermediate elongation of the main cord is 150% or more and 250% or less.

  Preferably, in the tire weave fabric, the number of dummy cords included in each of the dummy cord groups is 2 or more and 4 or less.

  Preferably, in the tire weave fabric, the number of main cords included in each main cord group is 5 or more and 15 or less.

  Preferably, in the tire weave fabric, the thickness of the dummy cord is equal to or less than the thickness of the main cord.

A method for manufacturing a pneumatic tire according to the present invention includes:
(1) A main code group including a plurality of parallel main codes and a dummy code group including a plurality of parallel dummy codes are provided, and the main code groups and the dummy code groups are alternately arranged. A step of forming a ply by laminating a sheet made of topping rubber to the bamboo woven fabric,
(2) The ply is cut between one dummy code of the dummy code group and another dummy code located next to the one dummy code, and a strip is formed;
(3) the strip is spirally wound in the circumferential direction to form a band;
(4) The raw cover including the band includes a step of pressing and heating in the mold. In this manufacturing method, the intermediate elongation of the dummy cord is larger than the intermediate elongation of the main cord.

  In this pneumatic tire manufacturing method, a pattern is formed on the surface of the ply along the dummy cord. In the step of forming the strip, the ply is cut along the pattern.

  By using the weave fabric according to the present invention, the position of the main cord included in the ply can be easily specified from its appearance. For this reason, it is easy to adjust the distance between the knives provided in the cutting jig. This interwoven fabric can contribute to shortening the formation time of the strip. This weave fabric can contribute to tire productivity. Since the position of the dummy code is a mark, the main code is prevented from being cut when the strip is formed. Since the number of cords included in each strip is equal, bands having the same characteristics are formed in each manufactured tire. By using this interwoven fabric, the quality of the manufactured tire is stabilized. Since the intermediate elongation of the dummy cord is larger than the intermediate elongation of the main cord, the influence of the dummy cord on the tire restraining force is small. Even if the left side portion and the right side portion of the band are formed of different strips, a portion specific to the band is not formed, and thus the influence of this band on conicity is small. By using this interwoven fabric, a high-quality tire can be manufactured stably. This method of manufacturing a tire using a weave fabric is excellent in productivity and can manufacture a high-quality tire.

FIG. 1 is a cross-sectional view showing a part of a pneumatic tire manufactured by the manufacturing method of the present invention. FIG. 2 is a cross-sectional perspective view showing a part of a strip constituting a band provided in the tire of FIG. 1. FIG. 3 is a schematic view showing a part of a ply used for forming the strip of FIG. FIG. 4 is a cross-sectional perspective view showing a part of the ply of FIG. FIG. 5 is a cross-sectional view showing a cutting state of the ply of FIG. FIG. 6 is a cross-sectional perspective view showing a part of a strip used for forming a band of a pneumatic tire.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  The pneumatic tire 8 shown in FIG. 1 includes a tread 10, a sidewall 12, a bead 14, a carcass 16, a belt 18, a band 20, an inner liner 22, and a chafer 24. The tire 8 is a tubeless type. The tire 8 is attached to a passenger car. In FIG. 1, the vertical direction is the radial direction, the horizontal direction is the axial direction, and the direction perpendicular to the paper surface is the circumferential direction. The tire 8 has a substantially bilaterally symmetric shape with the one-dot chain line CL in FIG. 1 as the center. This alternate long and short dash line CL represents the equator plane of the tire 8.

  The tread 10 is made of a crosslinked rubber having excellent wear resistance. The tread 10 has a shape protruding outward in the radial direction. The tread 10 includes a tread surface 26. The tread surface 26 is in contact with the road surface. A groove 28 is carved in the tread surface 26. The groove 28 forms a tread pattern. The groove 28 may not be cut in the tread 10.

  The sidewall 12 extends substantially inward in the radial direction from the end of the tread 10. The sidewall 12 is made of a crosslinked rubber. The sidewall 12 absorbs an impact from the road surface by bending. Further, the sidewall 12 prevents the carcass 16 from being damaged.

  The bead 14 is located substantially inward of the sidewall 12 in the radial direction. The bead 14 includes a core 30 and an apex 32 that extends radially outward from the core 30. The core 30 has a ring shape. The core 30 is formed by winding a non-stretchable wire (typically a steel wire). The apex 32 is tapered outward in the radial direction. The apex 32 is made of a highly hard crosslinked rubber.

  The carcass 16 includes a carcass ply 34. The carcass ply 34 is bridged between the beads 14 on both sides, and extends along the inside of the tread 10 and the sidewall 12. The carcass ply 34 is folded around the core 30 from the inner side to the outer side in the axial direction. Although not shown, the carcass ply 34 includes a plurality of cords arranged in parallel and a topping rubber. The absolute value of the angle formed by each cord with respect to the equator plane is usually 70 ° to 90 °. In other words, the carcass 16 has a radial structure. The cord is usually made of organic fibers. Examples of preferable organic fibers include polyester fibers, nylon fibers, rayon fibers, polyethylene naphthalate fibers, and aramid fibers. A carcass 16 having a bias structure may be employed.

  The belt 18 is located outside the carcass 16 in the radial direction. The belt 18 is laminated with the carcass 16. The belt 18 reinforces the carcass 16. The belt 18 includes an inner layer 36 and an outer layer 38. Although not shown, each of the inner layer 36 and the outer layer 38 is composed of a large number of cords arranged in parallel and a topping rubber. Each cord is inclined with respect to the equator plane. The absolute value of the tilt angle is not less than 10 ° and not more than 35 °. The cord inclination direction of the inner layer 36 is opposite to the cord inclination direction of the outer layer 38. A preferred material for the cord is steel. An organic fiber may be used for the cord.

  The band 20 is located on the inner side in the radial direction of the tread 10. The band 20 is located on the radially outer side of the belt 18. The band 20 covers the belt 18. This band 20 is formed using the strip 40 shown in FIG.

  As shown in the figure, the strip 40 is composed of twelve cords 42 and a topping rubber 44 arranged in parallel. Each cord 42 is covered with a topping rubber 44. In FIG. 2, the cord 42 extends in the direction indicated by the double arrow A. The strip 40 also extends in the direction indicated by the double arrow A.

  The twelve cords 42 included in the strip 40 are composed of ten main cords 42a and two dummy cords 42b. These main cords 42 a are arranged at equal intervals in the width direction of the strip 40. In this specification, the group consisting of these main codes 42a is referred to as a main code group MG. The dummy code 42b is arranged on both sides of the main code group MG.

  In the tire 8, the band 20 is formed by spirally winding the strip 40 in the circumferential direction. Since the extending direction of the strip 40 is aligned with the circumferential direction during winding, the main cord 42a is also wound spirally in the circumferential direction. The band 20 has a jointless structure. The band 20 can contribute to the rigidity in the radial direction. In the tire 8, the influence of the centrifugal force acting during traveling is suppressed.

  In the method of manufacturing the tire 8, the strip 40 is formed using the ply 46 shown in FIG. The ply 46 is composed of a blind fabric 48 and a topping rubber 44. The interwoven fabric 48 includes a large number of cords 42 as warps and wefts 50. These codes 42 are arranged at equal intervals. As shown in the figure, in the weave fabric 48, wefts 50 are roughly driven into the cords 42 arranged in parallel. The weft 50 restrains these cords 42. The weft 50 holds the shape of the weave fabric 48. Examples of the weft 50 include cotton fibers and polynosic fibers. In FIG. 3, the double arrow A indicates the extending direction of the cord 42.

  The numerous cords 42 constituting the blind fabric 48 are composed of the plurality of main cord groups MG composed of the ten main cords 42a and the plurality of dummy cord groups DG composed of the two dummy cords 42b. . As shown in the drawing, dummy code groups DG are arranged on both sides of the main code group MG. Main code groups MG are arranged on both sides of the dummy code group DG. The main code group MG and the dummy code group DG are alternately arranged.

  FIG. 4 is a cross-sectional perspective view showing a part of the ply 46 of FIG. FIG. 4 shows a portion of the ply 46 where the dummy code group DG is located. The two dummy codes 42b included in the dummy code group DG are arranged in parallel. Main codes 42a are disposed on both sides of the dummy code group DG.

  Although not shown, in the dummy code group DG, a pattern is formed along the dummy code 42b on each of the upper surface and the lower surface thereof. This pattern is stripe-like. A region SP is shown as a region SP. Since this pattern can be visually recognized, the position of the dummy code 42b can be specified by grasping the position of this pattern. Since the main code group MG is located next to the dummy code group DG, the position of the main code 42a can be grasped using the position of the dummy code 42b specified by the pattern formed on the surface as a mark.

  In the manufacturing method of the tire 8, the specification and the like are taken into consideration, and the number of main cords 42a included in the main code group MG and the number of dummy cords 42b included in the dummy code group DG are determined. After a large number of main cords 42a and a large number of dummy cords 42b are juxtaposed, wefts 50 are driven in to form a weave fabric 48 in which main cord groups MG and dummy cord groups DG are alternately arranged. A sheet made of the topping rubber 44 is bonded to the blind fabric 48 to form a ply 46. The ply 46 is cut with a knife to form a strip 40.

  FIG. 5 is a cross-sectional view showing a cutting state of the ply 46 of FIG. In FIG. 5, a knife 54 is shown together with a ply 46. As shown in the drawing, the knife 54 is located between one dummy code 42b and another dummy code 42b located next to the one dummy code 42b, which is grasped from the pattern formed in the region SP. positioned. By passing the knife 54 at this position, the ply 46 is cut. In the manufacturing method of the tire 8 using the interwoven fabric 48, since the position of the main cord 42a can be grasped based on the pattern formed on the surface thereof, the cutting of the main cord 42a by the knife 54 is effectively prevented. Can be done.

  Although not shown, in this manufacturing method, a cutting jig provided with a number of knives 54 is used for cutting the ply 46. In this cutting step, the positions of the knives 54 are adjusted so that the distance between the knives 54 is equal to the width of the strip 40. Since the positions of the main cord 42a and the dummy cord 42b can be specified by the stripe-like pattern, the end portion of the ply 46 is disassembled and the cord 4 is exposed in order to grasp the position of each cord 4 as in the conventional manufacturing method. There is no need to let them. According to this manufacturing method, the position adjustment of the knife 54 is easy. Moreover, a large number of strips 40 with the same number of main cords 42a can be produced in one slit. This manufacturing method using the weave fabric 48 can contribute to the productivity of the tire 8. Since the characteristics of each strip 40 are stabilized, the band 20 having the same characteristics is formed in each tire 8 manufactured by this manufacturing method. This manufacturing method using the interwoven fabric 48 can stably manufacture the high-quality tire 8.

  In this manufacturing method, the strip 40 is supplied to a former (not shown) together with members such as the carcass ply 34, the bead 14, the belt 18, and the tread 10. The carcass ply 34 is wound around this former to form a cylinder. A bead 14 is combined with a cylindrical carcass ply 34. When the bead 14 reaches a predetermined position, the apex 32 constituting the bead 14 is pushed down. The carcass ply 34 is folded around the core 30. The belt 18 is laminated on a portion of the carcass ply 34 corresponding to the inner side in the radial direction of the tread 10. Outside the belt 18, the strip 40 is spirally wound in the circumferential direction to form the band 20.

  In this manufacturing method, two strips 40 are used when forming the band 20 from the viewpoint of productivity. Each strip 40 is spirally wound axially outward from the equator plane or vice versa. In the tire 8, the portions of both sides of the band 20 across the equator plane are formed by strips 40. In this manufacturing method, the number of main cords 42a included in each strip 40 is equal. For this reason, a peculiar part is not formed in the band 20 formed using the two strips 40. In the tire 8, the influence of the band 20 on conicity is suppressed. By using the interwoven fabric 48, the high-quality tire 8 can be manufactured stably.

  In this manufacturing method, the tread 10 is further combined with the outer side of the formed band 20, and a low cover (not shown) is obtained. The raw cover is put into a mold (not shown) held at a predetermined temperature. The raw cover is pressed between the cavity surface of the mold and the outer surface of a bladder (not shown). The raw cover is heated by heat conduction from the bladder and the mold. While the rubber composition of the low cover flows by the pressurization and heating, the rubber composition causes a crosslinking reaction, and the tire 8 is obtained.

In this manufacturing method, the intermediate elongation of the dummy cord 42b is larger than the intermediate elongation of the main cord 42a. The high intermediate elongation dummy cord 42b does not hinder the binding force of the band 20. In the tire 8, the band 20 can effectively contribute to running stability. From this viewpoint, the ratio of the intermediate elongation of the dummy cord 42b to the intermediate elongation of the main cord 42a is preferably 150% or more. In this manufacturing method, it is preferable that the ratio of the intermediate elongation is 250% or less from the viewpoint that the moldability of the interwoven fabric 48 can be appropriately maintained. In addition, this intermediate elongation is a material testing machine (“2005 type” manufactured by Intesco) under the following conditions in accordance with the provisions of a) standard time test in Section 8.7 of “JIS L 1017”. It is the elongation at constant load measured by
Test temperature: 20 ° C
Test humidity: 65%
Material grip interval: 250 mm
Tensile speed: 300 mm / min

  In this manufacturing method, the number of main cords 42a included in the main cord group MG is preferably 5 or more and 15 or less. By setting the number to 5 or more, the band 20 can be efficiently formed by the strip 40. This manufacturing method is excellent in productivity. By setting the number to 15 or less, the band 20 having a sufficient restraining force is formed. The tire 8 manufactured by this manufacturing method is excellent in running stability.

  In this manufacturing method, the number of dummy codes 42b included in the dummy code group DG is preferably 2 or more and 4 or less. By setting the number to be two or more, the ply 46 in which the position of the dummy cord 42b can be easily specified is obtained. The ply 46 can contribute to stable production of the high-quality tire 8. By setting the number to 4 or less, the influence of the dummy cord 42b on the tire performance can be suppressed.

  In this manufacturing method, the main cord 42a is made of an organic fiber. Examples of preferable organic fibers include nylon fibers, polyester fibers, rayon fibers, polyethylene naphthalate fibers, and aramid fibers. From the viewpoint of running stability, polyethylene naphthalate fiber and aramid fiber are preferred. The main cord 42a may be a steel cord.

  The thickness of the main cord 42a is preferably 800 dtex / 2 or more and 2000 dtex / 2 or less. By setting the thickness to 800 dtex / 2 or more, the band 20 can effectively contribute to running stability. By setting the thickness to 2000 dtex / 2 or less, the rigidity of the band 20 is appropriately maintained. In the tire 8, excellent riding comfort is maintained. From this viewpoint, the thickness is preferably 1200 dtex / 2 or less. The thickness of the main cord 42a is measured in accordance with JIS L 1017. This thickness is the positive fineness of the cord 42 defined in JIS L 1017-8.3 (b). The thickness of a dummy code 42b described later is also measured in the same manner.

  In this manufacturing method, the dummy cord 42b is made of an organic fiber. Examples of preferable organic fibers include nylon fibers, polyester fibers, rayon fibers, polyethylene naphthalate fibers, aramid fibers, and cotton fibers. From the viewpoint of suppressing the influence on the production cost, the thickness of the dummy cord 42b is preferably equal to or less than the thickness of the main cord 42a.

  Hereinafter, the effects of the present invention will be clarified by examples. However, the present invention should not be construed in a limited manner based on the description of the examples.

[Experiment 1 Experiment on strip workability]
[Example 1]
A weave fabric was prepared in which a main cord group consisting of 10 main cords arranged in parallel at equal intervals and a dummy code group consisting of two dummy cords arranged in parallel at equal intervals were arranged alternately. This weave fabric includes 150 main cord groups and 149 dummy cord groups. Therefore, this weave fabric includes 1500 main cords and 298 dummy cords. The main cord is made of nylon fiber. The thickness of this main code was 1400 dtex / 2. The intermediate elongation of the main cord is 10%. This dummy cord is made of polyester fiber. The thickness of the dummy code was 1100 dtex / 2. The intermediate elongation of this dummy cord is 19%.

[Comparative Example 1]
A conventional weave fabric with 1500 main cords in parallel was prepared. This blind fabric does not contain dummy cords. This main code is equivalent to the main code used in the first embodiment.

[Evaluation of processing time]
A ply having the configuration shown in FIG. 3 was formed using the weave fabric of Example 1. On the surface of the ply, 149 stripe portions are formed. In this ply, a mother tape was formed by passing a knife through every 10 stripe portions. This mother tape includes 10 main code groups and 9 dummy code groups. Each of the nine stripes on the surface of the mother tape was passed through a knife to form a strip having the configuration shown in FIG. 150 strips were formed from one ply. In this formation, a time T1 until 15 mother tapes were formed from one ply was measured. The time T2 until 10 strips were formed from one mother tape was measured. A time T3 from the 15 mother tapes until 150 strips were formed was measured. These measured times T1, T2 and T3 are shown in Table 1 below.

  A ply was formed using the interwoven fabric of Comparative Example 1. The end of this ply was disassembled to expose the end of the main cord. A knife was passed through every 100 main cords to form 15 mother tapes. In one mother tape, a knife was passed through every 10 main cords to form 10 strips having the configuration shown in FIG. 150 strips were formed from one ply. Also during this formation, the time T1 from the formation of one mother ply to the formation of 15 mother tapes was measured. The time T2 until 10 strips were formed from one mother tape was measured. A time T3 from the 15 mother tapes until 150 strips were formed was measured. These measured times T1, T2 and T3 are shown in Table 1 below.

  As shown in Table 1, times T1, T2, and T3 when using the interwoven fabric of Example 1 are shorter than times T1, T2, and T3 when using the interwoven fabric of Comparative Example 1. It can be seen that the interwoven fabric of Example 1 can contribute to strip productivity. From this evaluation result, the superiority of the present invention is clear.

[Experiment 2 Tire Performance Evaluation 1]
[Formation of strip A]
A strip A having the configuration shown in FIG. 2 was formed using the interwoven fabric of Example 1 above. The strip A includes ten main codes and two dummy codes, and the dummy codes are arranged on both sides of the ten main codes arranged in parallel. The main cord is made of nylon fiber. The thickness of this main code was 1400 dtex / 2. The intermediate elongation of the main cord is 10%. This dummy cord is made of polyester fiber. The thickness of the dummy code was 1100 dtex / 2. The intermediate elongation of this dummy cord is 19%.

[Formation of strip B]
A strip B was obtained in the same manner as the strip A except that the number of dummy codes included in the dummy code group was four. The strip B includes 10 main codes and 4 dummy codes. In the strip B, two dummy codes are arranged on both sides of the ten main codes arranged in parallel.

[Formation of strip C]
A strip C having the configuration shown in FIG. 6 was formed using the interwoven fabric of Comparative Example 1 described above. This strip C does not include a dummy code. The strip C includes ten main cords. This main code is equivalent to the main code used for the strip A.

[Formation of strips D and E]
Strips D and E were formed in the same manner as the strip C except that the number of main cords was changed. Accordingly, each of strips D and E does not include a dummy code. The strip D includes 12 main cords. The strip E includes 14 main cords.

[Example 2]
A tire of Example 2 having the basic configuration shown in FIG. 1 and the specifications shown in Table 2 below was obtained. The tire size was 215 / 45R17. In this tire, the band is formed using the strip A.

[Example 3 and Comparative Example 2-4]
A tire was obtained in the same manner as in Example 2 except that the strip constituting the band was as shown in Table 2 below.

[High-speed durability evaluation]
The high-speed durability based on the ECE30 standard was evaluated. A speed V (km / h) at which the prototype tire was damaged and a time M (minutes) from when the speed was reached to when the tire was damaged were obtained. The results are shown in Table 2 below. The higher the speed and the longer the time, the better the high-speed durability.

[Evaluation of Uniformity]
Conicity was measured according to the conditions of the uniformity test defined in “JASO C607: 2000”. The average value of the results of measuring 20 tires is shown in Table 2 below. The smaller this number, the higher the evaluation.

[Evaluation of workability]
The time required to prepare the strip was determined. This required time is the sum of the times T1, T2 and T3 obtained in Experiment 1 above. The results are shown in Table 2 below. It is shown that workability is excellent, so that this value is small.

  As shown in Table 2, the tire of the example is superior in productivity to the tire of the comparative example. The tire of this example has high-speed durability and conicity equivalent to the tire of the comparative example. From this evaluation result, the superiority of the present invention is clear.

[Experiment 3 Tire Performance Evaluation 2]
[Test Example 1]
A tire having the basic configuration shown in FIG. 1 and the specifications shown in Table 3 below was obtained. The tire size was 195 / 65R15. In this tire, two strips A were used in forming the band. Each strip A was spirally wound from the end of the belt toward the equator plane. In this tire, the right part and the left part of the band with the equator plane of the band are both formed of the strip A.

[Test Example 2-25]
Tires were obtained in the same manner as in Test Example 1 except that the strips constituting the right and left portions of the band were as shown in Table 3, Table 4 and Table 5 below.

[Evaluation of Uniformity]
Conicity was measured in the same manner as in Experiment 2 above. The average values of the results of measuring 20 tires are shown in Tables 3, 4 and 5 below. The smaller this number, the higher the evaluation.

  As shown in Table 3, Table 4, and Table 5, it was confirmed that the influence of the dummy code on the conicity was small.

  The weave fabric described above can also be applied to the manufacture of various tires.

2, 40 ... Strip 4 ... Cord 6 ... Topping rubber 8 ... Tire 10 ... Tread 12 ... Side wall 14 ... Bead 16 ... Carcass 18 ... Belt 20 ... Band 42 ... Cord 42a ... Main cord 42b ... Dummy cord 46 ... Ply 48 ... Bann fabric 50 ... Weft

Claims (8)

A main code group including a plurality of parallel main codes and a dummy code group including a plurality of parallel dummy codes;
This main code group and this dummy code group are arranged alternately,
A tire weave fabric in which the intermediate elongation of the dummy cord is greater than the intermediate elongation of the main cord.   The tire weave fabric according to claim 1, wherein a ratio of the intermediate elongation of the dummy cord to the intermediate elongation of the main cord is 150% or more and 250% or less.   3. The tire weave fabric according to claim 1 or 2, wherein the number of dummy cords included in each of the dummy cord groups is 2 or more and 4 or less.   The tire weave fabric according to any one of claims 1 to 3, wherein the number of main cords included in each of the main cord groups is 5 or more and 15 or less.   5. The tire weave fabric according to claim 1, wherein a thickness of the dummy cord is equal to or less than a thickness of the main cord. A main code group including a plurality of parallel main codes and a dummy code group including a plurality of parallel dummy codes are provided, and the main code groups and the dummy code groups are alternately arranged. A process in which a sheet made of topping rubber is bonded to the fabric and the ply is formed;
The ply is cut between one dummy code of the dummy code group and another dummy code located next to the one dummy code to form a strip;
The strip is spirally wound in the circumferential direction to form a band;
The raw cover including the band includes a step of pressing and heating in the mold,
A method of manufacturing a pneumatic tire in which the intermediate elongation of the dummy cord is larger than the intermediate elongation of the main cord. On the surface of the ply, a pattern is formed along the dummy cord,
The method for manufacturing a pneumatic tire according to claim 6, wherein the ply is cut along the pattern in the step of forming the strip.   The pneumatic tire manufactured with the manufacturing method of the said Claim 6 or 7.

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