JP7055276B2 - Pneumatic tires and how to make them - Google Patents

Description

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

Pneumatic tires are manufactured by laminating a plurality of types of strip-shaped tire materials such as carcass ply on a tire forming drum to form a raw tire. When the tire material is laminated on the tire forming drum, the start end portion and the end portion of the tire material are usually overlapped and jointed.

FIG. 5 is a schematic perspective view of the overlap joint portion of the carcass ply constituting the conventional pneumatic tire as viewed from above the side surface, and FIG. 6 is a cross-sectional view of the VI-VI. As shown in FIG. 5, the carcass ply 50 has a textile cord (warp) 52 densely arranged at predetermined intervals and a weft cord (two in FIG. 5) sparsely arranged in a direction substantially perpendicular to the textile cord 52. It is formed by coating (topping) rubber 56 on both sides of a textile member woven with 54 (indicated by a dotted line).

The carcass ply 50 is pre-cut to a predetermined size at an anvil portion on a conveyor (not shown) for transporting the carcass ply 50 in a two-stage forming machine, and then is pre-cut to a predetermined size, and then a tire forming drum (not shown) together with other materials. It is pasted on top. As shown in FIGS. 5 and 6, the carcass ply 50 wound around the tire forming drum is joined by overlapping the end portion 50b with the start end portion 50a, and the carcass layer including the overlap joint portion 60 is formed. It is formed (Patent Document 1, Patent Document 2).

However, in such an overlap joint, a rigidity difference occurs between the overlap joint portion 60 and other portions, and when the product tire is inflated, the overlap joint portion 60 having high rigidity locally swells. However, there is a risk that a dent in the radial direction will occur on the side of the tire.

Since the occurrence of such dents deteriorates the appearance quality of the tire, conventional measures have been taken to reduce the degree of overlap (overlap amount). For example, the joint amount J in the overlap joint portion 60 is set. Minimal joints that are made smaller, zipper joints, claw joints, and the like that joint the start end portion 50a and the end portion 50b in a state where they do not form an overlap portion are used. In these methods, the occurrence of dent can be suppressed by making the overlap joint portion having a rigidity difference from that of other portions smaller or by eliminating the overlap joint portion.

However, although the above methods can improve the problem of dent, each has a problem.

That is, when the extremely small joint is adopted, the dent level is improved to some extent, but it has not yet been improved to a dent level sufficient for the market demand.

In addition, when zipper joints and claw joints are used, it is possible to dramatically improve the dent level and eliminate the occurrence of dents, but joints using these require a complicated mechanism. High equipment installation costs are required. In addition, since it takes time to perform the joint work, there is a problem that the productivity is greatly reduced.

In addition, since the zipper joint and the claw joint are joined by butt joint without forming an overlap portion, the coupling force of the joint portion is lower than that of the overlap joint, and the joint portion is formed when the low cover is shaped. May open and open joints may occur.

Further, an insulation (sheet rubber) is attached on the outer periphery of the carcass ply 50 to suppress the opening of the end on the side of the overlap joint portion and suppress the dent. However, while this method is extremely effective in improving dents, it imposes a heavy load on production costs and productivity, and may lead to an increase in tire weight and a decrease in fuel efficiency. ..

Japanese Unexamined Patent Publication No. 2016-10933 Japanese Unexamined Patent Publication No. 2006-21514

Therefore, the present invention improves the dent level more than before and reduces the occurrence of open joints while using an overlap joint that is not expensive like a zipper joint or a claw joint and has excellent productivity. Further, it is an object to provide a pneumatic tire having excellent quality such as appearance and a manufacturing technique thereof.

The present inventor has diligently studied the solution to the above-mentioned problem, found that the above-mentioned problem can be solved by the invention described below, and has completed the present invention.

The invention according to claim 1 is
A rubber-coated carcass ply is wound on both sides of a textile member in which textile cords arranged at predetermined intervals and wefts arranged in a direction substantially perpendicular to the textile cord are woven together. It ’s a tire,
At at least one end of the start and end of the carcass ply joined by winding and overlapping, the warp and weft located between the arranged textile cords is cut .
At the starting end, the warp and weft is cut by a notch having a triangular cross section formed on the back surface of the starting end.
At the end, the warp and weft is a pneumatic tire formed on the surface of the end and whose cross section is cut by a triangular notch .

The invention according to claim 2 is
The pneumatic tire according to claim 1, wherein the warp and weft is cut between all the textile cords at at least one end of a start end and an end portion of the carcass ply.

The invention according to claim 3 is
The pneumatic tire according to claim 1 or 2, wherein the range in which the warp and weft is cut is a range of 2 to 10 mm from the tip of the start end portion or the end end portion of the carcass ply.

The invention according to claim 4 is
The pneumatic tire according to any one of claims 1 to 3, wherein the joint amount at the overlap joint between the tip end portion and the end portion of the carcass ply is 2 to 10 mm.

The invention according to claim 5 is
A rubber-coated carcass ply is cut on both sides of a textile member in which wefts arranged at predetermined intervals and wefts arranged in a direction substantially perpendicular to the textile cord are woven into a tire forming drum. It is a method of manufacturing pneumatic tires by pasting and manufacturing pneumatic tires.
A cutting step of cutting the carcass ply to a predetermined size and
A warp and weft cutting step of cutting the warp and weft located between the arranged textile cords at at least one end of the cut end and end of the carcass ply.
The carcass ply from which the weft has been cut is attached to the tire forming drum, and the joint step of overlapping jointing the start end portion and the end portion of the carcass ply is included.
In the warp and weft cutting step, the warp and weft is cut by forming a notch having a triangular cross section on the back surface of the start end portion at the start end portion, and the cross section is triangular on the surface of the end portion at the end portion. A method for manufacturing a pneumatic tire, which comprises cutting the warp and weft by forming a notch in a shape .

The invention according to claim 6 is
5. The process of claim 5, wherein the warp and weft cutting step is a step of cutting the warp and weft between all the textile cords at at least one end of the start end portion and the end portion of the carcass ply. This is a method for manufacturing pneumatic tires.

The invention according to claim 7 is
The method for manufacturing a pneumatic tire according to claim 5 or 6, wherein the range for cutting the warp and weft is a range of 2 to 10 mm from the tip of the start end portion or the end end portion of the carcass ply. ..

The invention according to claim 8 is
The method for manufacturing a pneumatic tire according to any one of claims 5 to 7, wherein the joint amount at the overlapping joint between the tip end portion and the end portion of the carcass ply is 2 to 10 mm. Is.

The air-filled invention according to claim 9, wherein the weft cutting step is a step of cutting the weft using a comb-shaped cutter. This is a tire manufacturing method.

The invention according to claim 10 is
The method for manufacturing a pneumatic tire according to any one of claims 5 to 8, wherein the weft cutting step is a step of cutting the weft using a gear-shaped cutter.

According to the present invention, the dent level is improved and the occurrence of open joints is reduced while using an overlap joint which is not expensive like a zipper joint or a claw joint and has excellent productivity. Further, it is possible to provide a pneumatic tire having excellent quality such as appearance and a manufacturing technique thereof.

It is a schematic perspective view which looked at the overlap joint part of the carcass ply which constitutes one Embodiment of the pneumatic tire which concerns on this invention from the side surface upper side. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. It is a schematic perspective view for demonstrating one Embodiment of the manufacturing method of the pneumatic tire which concerns on this invention. It is a schematic perspective view for demonstrating another embodiment of the manufacturing method of the pneumatic tire which concerns on this invention. It is a schematic perspective view which looked at the overlap joint part of the carcass ply which constitutes the conventional pneumatic tire from the upper side. FIG. 5 is a sectional view taken along line VI-VI of FIG.

Hereinafter, the present invention will be described based on the embodiments.

1. 1. Background to the present invention As described above, when the carcass ply is overlap-joined, the present inventor has a higher rigidity of the textile cord at the overlap-joint portion than the other portions, so that the air after production is obtained. We investigated the technical problem that dents occur in the overlap joint when the tires are inflated.

As a result, as shown in FIG. 6, in the overlap joint portion 60 of the carcass ply 50, the textile cords (warp) 52 of the start end portion 50a and the end portion 50b are each restrained by the weft 54, so that the textiles are adjacent to each other. The binding force between the cords 52 is strong and the rigidity is high. As a result, it was found that when inflating was performed after the product tire was manufactured, the overlap joint portion 60 having high rigidity did not swell locally and dents were generated.

Based on this finding, the present inventor can reduce the binding force of the textile cord at the overlap joint portion of the carcass ply to the product tire even if the start portion 50a and the end portion 50b are overlap jointed. Considering that the occurrence of dents can be sufficiently suppressed, experiments and studies were conducted, and the invention described below was completed.

2. 2. Pneumatic tire of the present invention (1) Outline The pneumatic tire of the present invention (hereinafter referred to as “tire”) is provided at at least one end of a start end portion and an end portion of the overlap joint portion of the wound carcass ply. , The weft located between the arranged textile cords is cut.

In this way, the warp and weft at at least one end of the start end and the end portion of the overlap joint portion of the carcass ply is cut between the textile cords arranged at predetermined intervals, whereby the overlap joint portion is formed. Since the restraint of the textile cord in the above is relaxed, the rigidity of the overlap joint portion does not increase. As a result, even when the product tire is inflated, the generation of dents is effectively suppressed at the overlap joint portion of the carcass ply, and it is possible to stably manufacture a pneumatic tire having excellent quality such as appearance. can. In cutting the weft, it is preferable that all the wefts at at least one end of the start end and the end portion are cut between all the textile cords, and further, the start end, the end, and both ends are cut. It is more preferable that the weft is cut at the portion.

(2) Tires of the present embodiment The tires of the present embodiment will be specifically described below with reference to the drawings. FIG. 1 is a schematic perspective view of the overlap joint portion of the carcass ply constituting the tire according to the present embodiment as viewed from above the side surface. FIG. 2 is a cross-sectional view taken along the line II-II of FIG.

As shown in FIG. 1, in the tire of the present embodiment, a sheet-shaped carcass ply 10 cut to a predetermined size is wound around a drum (not shown) to overlap the start end portion 10a and the end portion 10b. It is the same as the conventional one in that it has the overlap joint portion 20 formed by the above.

The carcass ply 10 is woven with textile codes 12 arranged at predetermined intervals and weft threads (indicated by a two-dot chain line in FIG. 1) 14 substantially orthogonal to the textile code (warp) 12. Both sides of the textile member are coated (topping) with rubber 16. The weft 14 is thin and has a role of holding the textile code 12 so that the textile code 12 is not disturbed when the rubber 16 is topping. In this respect as well, it is the same as the conventional one.

However, in the tire of the present embodiment, the weft 14 at at least one end of the start end 10a and the end 10b of the carcass ply 10 is cut between the textile cords 12 arranged at predetermined intervals. In this embodiment, the case where the wefts 14 at the ends of both the start end 10a and the end 10b are cut between the textile cords 12 arranged at predetermined intervals will be described.

Specifically, the back surface 10d of the start end portion 10a of the carcass ply 10 of the overlap joint portion 20 on the drum is a substantially intermediate position (indicated by a dotted line in FIG. 1) 13 and a weft 14 of adjacent textile codes 12. A notch 22 having a triangular cross section is formed at a portion substantially orthogonal to the above. Then, the warp and weft 14 is cut between the textile cords 12 arranged at predetermined intervals while maintaining the connection of the rubber 16 of the start end portion 10a of the carcass ply 10 of the overlap joint portion 20 by the notch 22. ..

Further, the surface 10c of the end portion 10b of the carcass ply 10 of the overlap joint portion 20 also has a notch 24 having a triangular cross section at a portion where the substantially intermediate position 13 of the adjacent textile code 12 and the weft 14 are substantially orthogonal to each other. It is formed. Then, by this notch 24, the weft 14 of the end portion 10b of the carcass ply 10 of the overlap joint portion 20 and the rubber 16 in the vicinity of the weft 14 are cut between the textile cords 12 arranged at predetermined intervals. There is.

The cutting range (length) of the weft 14 is adjusted to an appropriate value according to the size of the carcass ply 10, and the cutting range (hereinafter, also referred to as “cut width”) of the weft 14 is, for example, the starting end. It is preferably in the range of 2 to 10 mm inward from the tip of the portion 10a or the end portion 10b.

The joint amount J of the overlap joint portion 20 is adjusted to an appropriate value according to the width of the carcass ply 10, etc., but is in the range of 2 to 10 mm from the viewpoint of an appropriate joint amount that can suppress the open joint. Is preferable.

Examples of the tire suitable for the tire of the present embodiment include a tire having a 1-0 HTU (high turn up) structure or a tire having a 1-0 LTU (low turn up) structure. Since these tires have a single carcass structure, they are disadvantageous for dent suppression, but by applying this embodiment, a remarkable dent suppression effect can be exhibited for these structures as well. .. Further, a remarkable effect can be obtained by applying it to a tire structure having a flatness of 55% or more.

3. 3. Pneumatic Tire Manufacturing Method (1) Outline Next, a tire manufacturing method according to the present embodiment will be specifically described with reference to the drawings. FIG. 3 is a schematic perspective view for explaining a method for manufacturing a tire according to the present embodiment.

The attachment of the carcass ply 10 to the drum is the same as in the past in that it has a cutting process and a joint process, but it is the present implementation that a weft cutting process is provided between the cutting process and the joint process. It is a feature of the manufacturing method of the tire of the form.

(2) Method for manufacturing a tire according to the present embodiment The method for manufacturing a tire according to the present embodiment will be described in detail below.

(B) Cutting step In the cutting step, in a two-stage molding machine (not shown), a long carcass ply conveyed from the upstream side is precut to a predetermined size at an anvil portion on a conveyor that conveys the carcass ply.

(B) Weft cutting step After the carcass ply 10 is cut to a predetermined size, a weft cutting step is subsequently performed on a conveyor. As shown in FIG. 2, the weft 14 is cut within a predetermined range of at least one end of the start end 10a and the end 10b of the overlap joint portion 20 of the carcass ply 10.

In the warp and weft cutting step, as described above, it is preferable to cut all the warp and weft between all the textile cords at at least one end of the start end and the end portion of the carcass ply, and further at both ends. It is more preferable that the weft is cut. The cutting position of the weft 14 is adjusted to an appropriate value according to the length of the carcass ply 10 and the like, but the cutting range C (FIG. 3) of the weft 14 is inside from the tip of the start end portion 10a or the end end portion 10b. It is preferably in the range of 2 to 10 mm toward.

In the weft cutting process, there is a concern that the warp will be loosened due to the cutting of the weft, but since the adjacent textile cords other than the cut part are connected by rubber, the start end of the carcass ply of the overlap joint and the carcass ply at the overlap joint. There is no variation in the cut part at the end.

The weft cutting step is preferably performed using a comb-shaped cutter or a gear-shaped cutter on the conveyor of the molding machine. An example of the weft cutting process using these cutters will be described below.

(A) Weft cutting step using a comb-shaped cutter Here, the weft 14 at both ends of the start end portion 10a and the end portion 10b is cut using the comb-shaped cutters 30a and 30b. As shown in FIG. 3, the comb-shaped cutters 30a and 30b extend along a direction perpendicular to the transport direction of the carcass ply 10 (the width direction of the carcass ply 10), that is, in the stretching direction of the textile cord 12. On the other hand, it is provided in parallel. A plurality of comb-shaped cutters 30a and 30b are arranged side by side so that the wefts 14 arranged in the weft cutting range C are cut inward from the tips of the start end 10a and the end 10b, respectively. Further, the comb-shaped cutters 30a and 30b have the same number of comb-shaped cutter cutting blades 32a and 32b as the number of wefts 14 at equal intervals so that all the wefts 14 of the carcass ply 10 can be cut. ing.

The cutting blades 32a and 32b of the comb-shaped cutters 30a and 30b have a rectangular front view and a triangular side view. Then, in the comb-shaped cutters 30a and 30b, the pitch spacing of the cutting blades 32a and 32b of the comb-shaped cutter is set according to the spacing between the weft 14 of the start end portion 10a and the end portion 10b of the carcass ply 10 of the overlap joint portion 20. Has been done.

Once the operation of the conveyor of the molding machine is stopped, the carcass ply 10 is pre-cut to a predetermined size by the anvil portion on the conveyor, and then the lower comb-shaped cutter 30a is raised and the upper comb-shaped cutter is raised. As the 30b descends, the weft threads 14 at both ends of the start end 10a and the end 10b are cut using the lower comb-shaped cutter 30a and the upper comb-shaped cutter 30b, respectively.

(B) Warp and Weft Cutting Step by Gear Shape Cutter Here, the weft 14 at both ends of the start end 10a and the end 10b is cut by using the lower gear shape cutter 40a and the upper gear shape cutter 40b, respectively. .. FIG. 4 is a schematic perspective view for explaining a method of manufacturing a pneumatic tire using a gear-shaped cutter instead of a comb-shaped cutter.

The gear shape cutters 40a and 40b move along a direction perpendicular to the transport direction of the carcass ply 10 (width direction of the carcass ply 10), that is, move parallel to the stretching direction of the textile cord 12. It is provided so that it can be done.

The cut blades 42a and 42b of the gear shape cutter have a triangular front view and a triangular side view. Then, the gear shape cutters 40a and 40b are geared according to the spacing of the wefts 14 so that all the wefts 14 of the start end portion 10a and the end portion 10b of the carcass ply 10 of the overlap joint portion 20 can be cut. The pitch intervals of the cut blades 42a and 42b of the shape cutter are set.

Once the operation of the conveyor of the molding machine is stopped, the carcass ply 10 is pre-cut to a predetermined size by the anvil portion on the conveyor, and then the lower gear shape cutter 40a and the upper gear shape cutter 40b are the carcass ply 10. The weft thread 14 at both ends of the start end 10a and the end 10b is cut while rotating and moving along the width direction of the.

(C) Joint step After the weft cutting step, the transport conveyor starts transporting again, the carcass ply 10 is transported to a tire forming drum (not shown), and the carcass is transferred together with other rubber materials for tires including an inner liner. The back surface 10d of the start end portion of the ply is attached onto the tire forming drum toward the outer peripheral surface of the tire forming drum. In the carcass ply 10 wound around the tire forming drum, the carcass layer having the overlap joint portion 20 is formed by overlapping jointing the end portion 10b with the start end portion 10a. At this time, the joint amount J of the overlap joint portion 20 is adjusted to an appropriate value according to the length of the carcass ply 10 and the like, but as described above from the viewpoint of an appropriate joint amount that can suppress the open joint. It is preferably in the range of 2 to 10 mm.

4. Effect of the present embodiment (1) According to the tire of the present embodiment, the wefts at at least one end of the overlap joint portion of the carcass ply are arranged at predetermined intervals. Since it is cut between the cords, the binding force between the adjacent textile cords is relaxed, the rigidity of the overlap joint part is relaxed, and the difference in rigidity between the overlap joint part and the other parts becomes larger. It gets smaller.

As a result, when a product tire having such an overlap joint portion is inflated, the overlap joint portion also expands appropriately in the same manner as the other portions, so that a local dent is generated on the outer periphery of the tire. Can be reduced and the dent level can be improved. Then, it is possible to provide a pneumatic tire having excellent appearance quality.

(2) According to the tire manufacturing method according to the present embodiment, even if a conventional overlap joint is adopted, it is possible to prevent the occurrence of dent only by providing a weft cutting step for cutting the weft. In the joint process, it is not necessary to provide a complicated mechanism as in the case of a butt joint. Therefore, it is possible to manufacture a pneumatic tire having a low manufacturing cost, high production efficiency, and excellent appearance quality.

Next, the present invention will be described more specifically by way of examples.

1. 1. Examples and Comparative Examples Using a carcass ply having a 1-0 LTU structure, 100 pneumatic tires having a tire size of 155 / 80R13 were produced (Examples 1 to 3 and Comparative Examples 1 to 4).

In Examples 1 to 3, the wefts at the start and end portions were cut on the conveyor after the pre-cutting of the carcass ply. In Examples 1 to 3, as shown in Table 1, the weft cut width and the joint amount are different from each other.

On the other hand, in Comparative Examples 1 to 4, pneumatic tires were produced without cutting the wefts at the start and end portions. As shown in Table 1, Comparative Examples 1 to 4 have different joint amounts.

2. 2. Test method After inflating the manufactured pneumatic tire at an internal pressure of 200 kPa, uniformity was measured and evaluated while rotating with an FV measuring device. Specifically, the amount of dent in the buttless portion was measured using a non-contact distance measurement sensor, and the dent evaluation of each pneumatic tire was performed by sensory evaluation. In addition, RFV value, RRO value and balance value were measured and evaluated.

3. 3. Evaluation Results The evaluation results are shown in Table 1. The rigidity of the overlap joint portion (rigidity of the joint portion), the RFV value, the RRO (Radial Run Out) value, the balance value, and the dent evaluation are shown by relative evaluation with Comparative Example 1 as 100. Here, the smaller the value of the joint portion rigidity, the lower the rigidity, the smaller the RFV value and the RRO value, the higher the performance, and the larger the balance value, the higher the performance. It shows that it is high. In addition, the dent evaluation indicates that the larger the value, the smaller the amount of dent.

In any of Examples 1 to 3, the rigidity is relaxed and the evaluation result of the dent is improved as compared with Comparative Example 1, and the wefts at the start and end of the overlap joint portion are cut after the precut of the carcass ply. As a result, it was found that the occurrence of dents at the overlap joint portion of the carcass ply can be appropriately suppressed.

Further, even when the examples in which the joint amounts are the same and the comparative examples are compared, the rigidity of the joint portion is lower in the embodiment in which the wefts at the start and end portions are cut, and dents are generated. It turned out that it can be suppressed appropriately.

Further, in Examples 1 to 3, the occurrence of dent could be suppressed even while maintaining the conventional joint amount.

From Table 1, the high-speed uniformity level is improved, and the low-speed RFV level and RRO level are improved by cutting the wefts at the start and end portions of the overlap joint portion after the pre-cut of the carcass ply 10. It was confirmed that an excellent pneumatic tire can be manufactured.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments. Various modifications can be made to the above embodiments within the same and equal range as the present invention.

10, 50 Carcass ply 10a, 50a Starting end 10b, 50b Ending part 10c Front surface of the end of the carcass ply 10d Back side of the beginning of the carcass ply 12, 52 Textile code 13 Approximately intermediate positions of adjacent textile cords 14, 54 Weft 16 , 56 Rubber 20, 60 Overlap joints 22, 24 Notches 30a, 30b Comb-shaped cutter 32a, 32b Comb-shaped cutter cutting blades 40a, 40b Gear-shaped cutter 42a, 42b Gear-shaped cutter cutting blade C Weft cutting range J Joint amount

Claims (10)

A rubber-coated carcass ply is wound on both sides of a textile member in which textile cords arranged at predetermined intervals and wefts arranged in a direction substantially perpendicular to the textile cord are woven together. It ’s a tire,
At at least one end of the start and end of the carcass ply joined by winding and overlapping, the warp and weft located between the arranged textile cords is cut .
At the starting end, the warp and weft is cut by a notch having a triangular cross section formed on the back surface of the starting end.
At the end portion, the warp and weft is a pneumatic tire formed on the surface of the end portion and having a cross section cut by a triangular notch . The pneumatic tire according to claim 1, wherein the warp and weft is cut between all the textile cords at at least one end of a start end and an end portion of the carcass ply. The pneumatic tire according to claim 1 or 2, wherein the range in which the warp and weft is cut is a range of 2 to 10 mm from the tip of the start end portion or the end end portion of the carcass ply. The pneumatic tire according to any one of claims 1 to 3, wherein the joint amount at the overlap joint between the tip end portion and the end portion of the carcass ply is 2 to 10 mm. A rubber-coated carcass ply is cut on both sides of a textile member in which wefts arranged at predetermined intervals and wefts arranged in a direction substantially perpendicular to the textile cord are woven into a tire forming drum. It is a method of manufacturing pneumatic tires by pasting and manufacturing pneumatic tires.
A cutting step of cutting the carcass ply to a predetermined size and
A warp and weft cutting step of cutting the warp and weft located between the arranged textile cords at at least one end of the cut end and end of the carcass ply.
The carcass ply from which the weft has been cut is attached to the tire forming drum, and the joint step of overlapping jointing the start end portion and the end portion of the carcass ply is included.
In the warp and weft cutting step, the warp and weft is cut by forming a notch having a triangular cross section on the back surface of the start end portion at the start end portion, and the cross section is triangular on the surface of the end portion at the end portion. A method for manufacturing a pneumatic tire, which comprises cutting the warp and weft by forming a notch in a shape . 5. The process of claim 5, wherein the warp and weft cutting step is a step of cutting the warp and weft between all the textile cords at at least one end of the start end portion and the end portion of the carcass ply. How to make a pneumatic tire. The method for manufacturing a pneumatic tire according to claim 5 or 6, wherein the range for cutting the warp and weft is a range of 2 to 10 mm from the tip of the start end portion or the end end portion of the carcass ply. The method for manufacturing a pneumatic tire according to any one of claims 5 to 7, wherein the joint amount at the overlapping joint between the tip end portion and the end portion of the carcass ply is 2 to 10 mm. .. The method for manufacturing a pneumatic tire according to any one of claims 5 to 8, wherein the weft cutting step is a step of cutting the weft using a comb-shaped cutter. The method for manufacturing a pneumatic tire according to any one of claims 5 to 8, wherein the weft cutting step is a step of cutting the weft using a gear-shaped cutter.

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