Method for manufacturing a rubber composite, method for manufacturing a tire

Abstract

The present application relates to a rubber composite manufacturing method, a tire manufacturing method. A rubber composite manufacturing method capable of suppressing the number of reels for supplying steel cords is provided. A rubber composite manufacturing method has: a reel setting step of setting a reel group in a steel cord supply device, the reel group being two or more reels each of which is wound with two or three steel cords; a pulling-out step of pulling out the steel cords each of which is wound on the reel; an arrangement step of arranging two or more steel cords pulled out from the reel group, that is, a steel cord group, in such a manner that the steel cords constituting the steel cord group are arranged in a row; and a rubber composite manufacturing step of manufacturing a rubber composite by embedding the steel cord group in rubber, the steel cord being a single wire steel cord, and a tension of 6.0% or more and 9.0% or less with respect to a breaking load of each of the steel cords constituting the steel cord group is applied to each of the steel cords when supplied to the arrangement step.

Description

Technical Field

[0001] This invention relates to a method for manufacturing rubber composites and a method for manufacturing tires. Background Technology

[0002] Patent Document 1 discloses a radial tire for passenger cars, which is a radial tire for passenger cars having a belt layer formed by embedding two or more single-line steel cords with circular cross sections in rubber. The tire is characterized in that the diameter d of the cords is in the range of 0.35 mm to 0.70 mm, and the rubber thickness D between the cords, measured perpendicular to the length direction of the cords, is in the range of 0.30 mm to 1.20 mm.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Microfilm of Japanese Patent Application No. 61-113799 (Japanese Patent Application No. 63-19404) Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In recent years, from the perspective of improving automobile fuel efficiency, there has been a demand for lightweight tires with low rolling resistance. To achieve tire lightweighting, previous research has focused on replacing stranded steel cords with single-ply steel cords with smaller cord diameters in the rubber composite used as the reinforcing layer of the tire, thereby making the rubber composite thinner.

[0008] However, when using single-ply steel cords with smaller diameters instead of stranded steel cords, the number of single-ply steel cords per unit width needs to be increased to ensure tire strength.

[0009] Furthermore, increasing the number of steel cords per unit width in the rubber composite requires increasing the number of steel cord rolls supplied during its manufacture. Therefore, this necessitates expanding the factory and modifying equipment.

[0010] Therefore, the object of the present invention is to provide a method for manufacturing a rubber composite capable of suppressing the number of rolls used to supply steel cord.

[0011] Methods for solving problems

[0012] The method for manufacturing a rubber composite of the present invention comprises: a roll setting step, wherein a roll assembly is set in a steel cord supply device, the roll assembly being two or more rolls each wound with two or three steel cords; a pull-out step, wherein two or three steel cords wound on the rolls are pulled out from the roll assembly using the steel cord supply device; an arrangement step, wherein the two or more steel cords pulled out from the roll assembly, i.e., the steel cord assembly, are arranged in a row in a cross section perpendicular to the length direction of the steel cords; and a rubber composite manufacturing step, wherein the steel cord assembly is embedded in rubber to manufacture a rubber composite, wherein the steel cords are single-strand steel cords, and a tension of 6.0% or more and 9.0% or less relative to the breaking load of each steel cord is applied to the steel cords constituting the steel cord assembly supplied to the arrangement step.

[0013] Invention Effects

[0014] According to the present invention, a method for manufacturing a rubber composite capable of suppressing the number of rolls used to supply steel cord can be provided. Attached Figure Description

[0015] Figure 1A This is a schematic diagram illustrating a method for manufacturing a rubber composite according to one aspect of the present invention.

[0016] Figure 1B This is a diagram schematically illustrating another configuration example of a method for manufacturing a rubber composite according to one aspect of the present invention.

[0017] Figure 2 This is a schematic diagram illustrating existing methods for manufacturing rubber composites.

[0018] Figure 3 This is an illustration of a roll that can be preferably used in a method for manufacturing a rubber composite according to one aspect of the present invention.

[0019] Figure 4 This is an explanatory diagram of the winding pitch of steel cord.

[0020] Figure 5 This is a cross-sectional diagram of the steel cord.

[0021] Figure 6A This is an explanatory diagram of the composite rollers in the arranging device used in the arranging process.

[0022] Figure 6B yes Figure 6A The side view of the composite roller shown.

[0023] Figure 6C This is an explanatory diagram of the guide plate in the arrangement device.

[0024] Figure 7 This is a cross-sectional view of a rubber composite according to one embodiment of the present invention.

[0025] Figure 8 This is an illustrative diagram of a tire according to one aspect of the present invention. Detailed Implementation

[0026] [Description of Embodiments of the Invention]

[0027] First, embodiments of the present invention will be described. In the following description, identical or corresponding elements will not be described repeatedly using the same symbols.

[0028] (1) A method for manufacturing a rubber composite according to one aspect of the present invention comprises: a roll setting step, wherein a roll assembly is set in a steel cord supply device, the roll assembly being two or more rolls each wound with two or three steel cords; a pull-out step, wherein two or three steel cords wound on the rolls are pulled out from the roll assembly using the steel cord supply device; an arrangement step, wherein the two or more steel cords pulled out from the roll assembly, i.e., the steel cord assembly, are arranged in a row in a cross section perpendicular to the length direction of the steel cords; and a rubber composite manufacturing step, wherein the steel cord assembly is embedded in rubber to manufacture a rubber composite, wherein the steel cords are single-strand steel cords, and a tension of 6.0% or more and 9.0% or less relative to the breaking load of each steel cord is applied to the steel cords constituting the steel cord assembly supplied to the arrangement step.

[0029] In one embodiment of the manufacturing method of the rubber composite of the present invention, two or three steel cords are wound on a roll. Therefore, the number of rolls can be set to half or one-third of the number of steel cords used. Thus, the number of rolls used to supply the steel cords can be controlled, and the number of steel cords per unit width of the rubber composite can be increased without factory expansion or equipment modification.

[0030] The two or three steel cords 12 wound on each drum 11 can be of the same length. In this case, it is possible to suppress the loss of steel cords when changing drums.

[0031] Furthermore, according to one aspect of the method for manufacturing a rubber composite, by suppressing the number of rolls used as described above, the freedom of setting the rolls is increased. Therefore, during the arrangement process, the feed angle when inserting the steel cord into the arrangement device can be easily selected. As a result, surface defects and coating peeling of the steel cord can be suppressed. Additionally, positional wobbling of the steel cord supplied to the arrangement device can be suppressed, allowing it to be supplied to a stable position.

[0032] In addition, by making the tension of the steel cords applied during the arrangement process greater than 6.0% of the breaking load of each steel cord, the position of the steel cords is stable and easy to align to the desired position during the arrangement process and the rubber composite manufacturing process.

[0033] This is believed to be because, due to the appropriate tension applied to the steel cord supplied to the arrangement process, its position is not easily displaced and remains stable even when an external force is applied to the steel cord.

[0034] As described above, the position of the steel cord is stable during the arrangement process and the rubber composite manufacturing process, thereby suppressing the deviation of the position of the steel cord in the thickness direction of the manufactured rubber composite.

[0035] The thickness of the rubber composite is a value obtained by adding the distribution width of the steel cords in the thickness direction of the rubber composite to the rubber thickness predetermined in a manner that allows the steel cords to be embedded. Therefore, by suppressing the deviation of the position of the steel cords in the thickness direction of the rubber composite, the thickness of the rubber composite can also be suppressed, thereby achieving weight reduction of the rubber composite and the tire using the rubber composite.

[0036] Furthermore, by stabilizing the position of the steel cord, excessive force is eliminated from the steel cord during the alignment process. Therefore, surface defects and coating peeling of the steel cord can be suppressed.

[0037] However, if the tension of each steel cord is excessively increased, the burden on the drum, steel cord supply device, etc., will also increase, and damage may occur. Therefore, as mentioned above, the tension of each steel cord relative to the breaking load of each steel cord is preferably 9.0% or less.

[0038] (2) Two steel cords can be wound on the above-mentioned drum.

[0039] By using two steel cords wound on the drum, the length of each steel cord can be made long enough to reduce the frequency of drum replacement.

[0040] (3) A tension adjustment process for adjusting the tension of the steel cord can be provided between the above-mentioned pulling-out process and the above-mentioned arranging process.

[0041] By implementing a tension adjustment process, the tension of the steel cord supplied to the arrangement process can be easily controlled within the desired range.

[0042] (4) In the above tension adjustment process, the tension of the steel cord can be adjusted by changing the position of the tension adjustment roller that is in contact with the conveyed steel cord.

[0043] The tension of the steel cord can be easily controlled by changing the position of the tension adjusting roller that contacts the conveyed steel cord. Furthermore, by using the tension adjusting roller, surface defects in the steel cord can be suppressed.

[0044] (5) As the above-mentioned tension adjustment process, it may have at least a first tension adjustment process and a second tension adjustment process.

[0045] By having at least a first tension adjustment process and a second tension adjustment process as tension adjustment processes, that is, by implementing tension adjustment processes in two or more processes, the tension of the steel cord can be controlled more precisely.

[0046] (6) The angle between the steel cord supplied before the above-mentioned arrangement process and the steel cord arranged after the above-mentioned arrangement process, i.e. the inlet angle, can be more than 40 degrees and less than 50 degrees.

[0047] By keeping the feed angle below 50 degrees, defects and coating peeling in the steel cord can be effectively suppressed. Furthermore, phenomena such as wire coiling, caused by twisting of the steel cord, can be prevented.

[0048] By making the infeed angle θ 40 degrees or more, steel cord can be stably supplied to the arranging device.

[0049] (7) One aspect of the tire manufacturing method of the present invention includes a tire manufacturing step of manufacturing a tire using a rubber composite obtained by the manufacturing method of a rubber composite as described in any one of (1) to (6).

[0050] According to one aspect of the tire manufacturing method of the present invention, since a rubber composite obtained by the above-described rubber composite manufacturing method is used, the manufactured tire can be made lighter. Furthermore, according to the above-described rubber composite manufacturing method, defects on the surface of the steel cords and coating peeling during the manufacturing of the rubber composite can be suppressed. Therefore, the adhesion between the steel cords and the rubber is excellent, and the durability of the tire using this rubber composite can also be improved.

[0051] [Details of the embodiments of the present invention]

[0052] The following description, with reference to the accompanying drawings, outlines a method for manufacturing a rubber composite, a method for manufacturing a tire, a rubber composite obtained by the above-described manufacturing method, and specific examples of a tire, representing one embodiment of the present invention (hereinafter referred to as "this embodiment"). It should be noted that the present invention is not limited to these examples, and the claims, as indicated by the claims, are intended to include all modifications within the meaning and scope equivalent to the claims.

[0053] [Manufacturing method of rubber composites]

[0054] The method for manufacturing the rubber composite according to this embodiment may include the following steps: roll setting, pulling out, arranging, and rubber composite manufacturing.

[0055] In the drum setup process, two or more drums, i.e., drum assemblies, can be set up in the steel cord supply device. It should be noted that each of the two or more drums constituting the drum assembly has two or three steel cords wound on it. Furthermore, the steel cords are single-strand steel cords.

[0056] During the pulling-out process, a steel cord supply device is used to pull out two or three steel cords respectively wound on the drums that make up the drum assembly.

[0057] In the arrangement process, two or more steel cords drawn from a group of drums, i.e., two or more drums, i.e., a group of steel cords, can be arranged in a row in a cross section that forms a group of steel cords perpendicular to the length direction of the steel cords.

[0058] In the manufacturing process of rubber composites, steel cord assemblies, i.e., two or more steel cords, can be embedded in rubber to create rubber composites.

[0059] The following uses Figures 1A to 6C Each process step is explained.

[0060] Figure 1A , Figure 1B This is a diagram schematically illustrating the manufacturing method of the rubber composite according to this embodiment. Figure 2 This is a schematic diagram illustrating existing methods for manufacturing rubber composites. Figure 3 This is an explanatory diagram of a roll wound with steel cord that can be preferably used in the manufacturing method of the rubber composite of this embodiment. Figure 4 This is an explanatory diagram of the winding pitch of steel cord. Figure 5 This is a cross-sectional diagram of the steel cord. Figures 6A to 6C This is an explanatory diagram illustrating an example of the configuration of a composite roller and guide plate in an arrangement device used in the arrangement process.

[0061] It should be noted that the rubber composite manufactured by the method of this embodiment will be described in detail later, but it has a cross-section perpendicular to the length direction of the steel cords contained therein, as shown below. Figure 7 The structure shown. Specifically, as... Figure 7 The rubber composite 40 shown has the following structure: the steel cords 12 constituting the steel cord group 2 are arranged in a row along the X-axis in the figure, and the steel cord group 2, that is, two or more steel cords 12, are embedded in the rubber 41.

[0062] (1) Roller setting process

[0063] like Figure 1A , Figure 1B As shown, in the drum setting process 100, two or more drums 11, i.e., drum group 1A, can be set in the steel cord supply device 10. The steel cord supply device 10 is a device that controls the rotation of the drums 11 and supplies the steel cord 12 wound on each drum 11. The steel cord supply device 10 is sometimes also referred to as a feed reel, etc. FIG1 shows a method of using one steel cord supply device 10 that can set two or more drums 11, but it is not limited to this method, and a single steel cord supply device 10 independent for each drum 11 can also be used.

[0064] Figure 1A , Figure 1B The illustration is schematic, so only two rolls 11 are shown. However, depending on the number of steel cords 12 contained in the manufactured rubber composite, two or more rolls 11 may be further provided in the roll setting process 100 in a direction perpendicular to the paper surface.

[0065] As mentioned above, to achieve tire weight reduction, single-ply steel cords with smaller cord diameters are used instead of stranded steel cords. Furthermore, when using single-ply steel cords, from the viewpoint of ensuring tire strength, it is necessary to increase the number of steel cords per unit width of the rubber compound.

[0066] However, in order to manufacture rubber composites with an increased number of steel cords per unit width, it is necessary to increase the number of steel cord rolls supplied. Therefore, there is a need to expand the factory and upgrade the equipment.

[0067] In contrast, in the manufacturing method of the rubber composite of this embodiment, two or three steel cords are wound on a single roll. Therefore, the number of rolls can be half or one-third of the number of steel cords used. Thus, the number of rolls used to supply the steel cords can be controlled, and the number of steel cords per unit width of the rubber composite can be increased without factory expansion or equipment modification.

[0068] Alternatively, the two or three steel cords 12 wound on each drum 11 can be of the same length. In this case, it is possible to suppress the loss of steel cords when changing drums.

[0069] Single-strand steel cords are wound onto each spool 11 as steel cords 12. By using single-strand steel cords, the cord diameter can be controlled compared to using stranded steel cords, thus reducing the thickness of the rubber composite and achieving weight reduction. Therefore, tires using this rubber composite can also be lightweight.

[0070] like Figure 2As shown, in the existing method of manufacturing a rubber composite that uses a single steel cord 12 wound on a spool 21, when manufacturing a rubber composite with an increased number of steel cords per unit width, the number of spools 21 with a single steel cord wound on them increases. That is, the number of spools constituting the spool group 1B increases. Therefore, the degree of freedom in the placement of the spools 21 decreases. As a result, Figure 2 The distribution width of the feed angle θ in the existing rubber composite manufacturing method shown is greater than that of the feed angle θ. Figure 1A , Figure 1B The distribution width of the feed angle θ in the manufacturing method of the rubber composite shown in this embodiment is wider. Therefore, some steel cords 12 have surface defects and coating peeling. In addition, during the manufacturing of the rubber composite, the position of the steel cords 12 supplied to the arranging device 14 sometimes wobbles. Furthermore, for the steel cord supply device 20, in order to cope with the increased number of rolls 21, it is also necessary to increase the number of ports of the rolls 21.

[0071] In contrast, according to the method for manufacturing the rubber composite of this embodiment, by suppressing the number of rolls 11 used as described above, the degree of freedom in the placement of the rolls 11 is increased. Therefore, in the arrangement process 102 described later, the feed angle θ when inserting the steel cord 12 into the arrangement device 14 can be easily selected. As a result, surface defects and coating peeling of the steel cord 12 can be suppressed. In addition, during the manufacturing of the rubber composite, positional wobbling of the steel cord 12 supplied to the arrangement device 14 can be suppressed, and it can be supplied to a stable position.

[0072] like Figure 1A , Figure 1B , Figure 2 As shown, the aforementioned feed angle θ refers to the angle between the steel cord 12 supplied before the arrangement process 102 and the steel cord 12 after the arrangement process 102. That is, the feed angle θ is the angle between the steel cord 12 before it is inserted into the arrangement device 14 and the steel cord 12 after it has been arranged. Figure 1A , Figure 1B The angle formed by the dashed line A in the diagram. It should be noted that in... Figure 2 In this case, the feed angle θ can also refer to the angle between the steel cord 12 before it is supplied to the arranging device 14 after the direction is changed by the guide roller 13 and the steel cord 12 after it is arranged by the arranging device 14.

[0073] exist Figure 1A , Figure 1B , Figure 2 In the process, due to the width of the paper, the infeed angle θ of the steel cord 12 inserted into the arrangement device 14 is only shown in the part where the infeed angle θ reaches its maximum value, but the infeed angle θ is calculated for each steel cord 12.

[0074] The aforementioned feed angle θ is preferably 50 degrees or less, and more preferably 48 degrees or less. This is because by making the feed angle θ 50 degrees or less, defects and coating peeling in the steel cord 12 can be particularly suppressed. Furthermore, it can suppress phenomena such as twisting of the steel cord, known as wire coiling.

[0075] Furthermore, the aforementioned feed angle θ is preferably 40 degrees or more, and more preferably 42 degrees or more. This is because by making the feed angle θ 40 degrees or more, the steel cord can be stably supplied to the arranging device 14.

[0076] The method of winding the steel cord 12 on the roll 11 used in the manufacturing method of the rubber composite in this embodiment is not particularly limited. For example, Figure 3 , Figure 4 As shown, the first steel cord 121 and the second steel cord 122 can be gathered together and wound into a spiral shape along the shaft 112 of the drum 11. The steel cord 12 can be wound on the shaft 112 of the drum 11 in multiple layers. Figure 3 , Figure 4 The diagram shows an example of two steel cords 12 being gathered together and wound around the shaft 112 of the drum 11, but even when there are three steel cords 12, they can be gathered together and wound along the shaft 112 of the drum 11 in the same way.

[0077] In addition, Figure 3 For example, flanges 111 may be provided only at both ends of the shaft 112 of the drum 11, but two or more flanges 111 may also be provided on the shaft 112 of the drum 11. The shaft 112 may be divided according to the number of steel cords wound on the drum 11 using the flanges 111. In this case, for example, the steel cords may be wound one by one in each region divided by the flanges 111 on the shaft 112.

[0078] As described above, two or three steel cords may be wound on the spool 11 used in the manufacturing method of the rubber composite in this embodiment, but it is particularly preferred that two steel cords are wound on the spool 11. As described above, by having two steel cords wound on the spool, the length of each steel cord can be sufficiently long, and the frequency of spool replacement can be suppressed.

[0079] The winding pitch P when winding the steel cord 12 on the shaft 112 of the drum 11 is not particularly limited and can be arbitrarily selected to wind the steel cord 12 to the desired length. The winding pitch P refers to the length of one turn of the steel cord 12 wound on the shaft 112 of the drum 11. This length refers to the length along the central axis CA of the drum 11 (refer to...). Figure 4 The length of ).

[0080] The diameter D of the steel cord 12 is preferably 0.20 mm or more and 0.45 mm or less, more preferably 0.25 mm or more and 0.40 mm or less. The reasons for the preferred range of the diameter D of the steel cord 12 will be explained later.

[0081] like Figure 5 As shown, the cord diameter D of the steel cord 12 refers to the diameter of the cross-section of the steel cord 12 perpendicular to its length direction. The cord diameter D of the steel cord 12 is preferably the average of the measured values ​​of three cross-sections perpendicular to its length direction. When measuring the cord diameter D using a micrometer or similar tool at the three cross-sections perpendicular to the length direction of the steel cord and calculating the average value, although it also depends on the length of the test piece of steel cord 12, it is preferable that the distance between adjacent cross-sections is 1 cm or more and 5 cm or less.

[0082] The material of the steel cord 12 is not particularly limited, for example, Figure 5 As shown, the steel cord 12 may have a configuration in which steel wires 31 are disposed and a coating 32 is disposed on the surface of the steel wires 31. The steel wires 31 and the coating 32 will also be described later.

[0083] (2) Pull-out process

[0084] like Figure 1A , Figure 1B As shown, in the pulling-out process 101, the steel cord supply device 10 simultaneously pulls out two or three steel cords 12 wound on each of the drum groups 1A, i.e., two or more drums 11.

[0085] During the pull-out process, all the steel cords 12 wound on each drum 11 are pulled out simultaneously. That is, when there are two steel cords wound on each drum 11, two steel cords 12 are pulled out simultaneously. Therefore, in the pull-out process 101, for example, a number of steel cords 12 can be pulled out by multiplying the number of drums constituting the drum group 1A by the number of steel cords 12 wound on each drum.

[0086] The steel cord 12 drawn out during the pulling process can be supplied to the arranging process. It should be noted that, in order to adjust the conveying direction of the steel cord 12, guide rollers (not shown) can also be installed on the conveying path of the steel cord 12 as needed.

[0087] In the method for manufacturing the rubber composite according to this embodiment, it is preferable to apply tension to the steel cords 12 supplied to the arranging process. For example, the ratio of the tension of each steel cord 12 supplied to the arranging process to the breaking load of each steel cord is preferably 6.0% or more and 9.0% or less, more preferably 6.0% or more and 8.5% or less, and even more preferably 6.5% or more and 8.5% or less.

[0088] The tension of each steel cord 12 refers to the tension applied to each steel cord 12, which can be adjusted by using the device for pulling the steel cords on the manufacturing production line and by implementing the tension adjustment process described later as needed.

[0089] By applying a tension of 6.0% or more relative to the breaking load of each steel cord during the arrangement process, the position of the steel cord 12 is stable and easily aligned to the desired position in the arrangement process 102 and the rubber composite manufacturing process 103 described later.

[0090] This is believed to be because, due to the appropriate tension applied to the steel cord 12 supplied to the arrangement process, its position is not easily displaced and remains stable even when an external force is applied to the steel cord 12.

[0091] As described above, in the arrangement process 102 and the rubber composite manufacturing process 103, the position of the steel cord 12 is stable, thereby suppressing the deviation of the position of the steel cord in the thickness direction of the manufactured rubber composite.

[0092] The thickness of the rubber composite is a value obtained by adding the distribution width of the steel cords 12 in the thickness direction of the rubber composite to the rubber thickness predetermined in a manner that allows the steel cords 12 to be embedded. Therefore, by suppressing the deviation of the position of the steel cords in the thickness direction of the rubber composite, the thickness of the rubber composite can be suppressed, and the rubber composite and the tire using the rubber composite can be made lighter.

[0093] Furthermore, by stabilizing the position of the steel cord 12, it is unnecessary to apply excessive force to the steel cord 12 during the arrangement process 102. Therefore, it is possible to suppress surface defects and coating peeling of the steel cord 12.

[0094] However, if the tension of each steel cord 12 is excessively increased, the burden on the drum 11, the steel cord supply device, etc., will also increase, and damage may occur. Therefore, as described above, the tension of each steel cord 12 relative to the breaking load of each steel cord is preferably 9.0% or less.

[0095] (3) Arrangement process

[0096] In the pulling process 101, as described above, two or more steel cords 12, i.e. steel cord groups 2, can be pulled out from the drum group 1A.

[0097] In the arrangement process 102, the steel cord group 2 pulled out from the drum group 1A through the pull-out process 101 can be arranged in such a way that the steel cords 12 forming the steel cord group 2 in a cross section perpendicular to the length direction of the steel cord 12 are arranged in a row.

[0098] As mentioned above, for example, Figure 7 As shown, in the manufactured rubber composite 40, the steel cords 12 constituting the steel cord group 2 are along... Figure 7 The X-axis is arranged in a row and embedded in rubber 41.

[0099] Therefore, in the arrangement process 102, the steel cords 12 constituting the steel cord group 2 can be arranged in a row before being embedded in the rubber 41. In the arrangement process 102, for example, two or more steel cords 12 constituting the steel cord group 2 can be arranged in a row using the arrangement device 14.

[0100] The configuration of the arranging device 14 is not particularly limited. For example, it may have a composite roller 141 that aligns the conveying direction of the steel cord 12 and a guide plate 142 that arranges the steel cord 12 in a row.

[0101] Specifically, for example Figure 6A , Figure 6B As shown, a composite roller 141 configured in a grid pattern can be used. Figure 6A A bottom view of the composite roller 141 is shown. Figure 6B A side view of the composite roller 141 is shown. The composite roller 141 may have a first roller 1411 disposed on a first layer and a second roller 1412 disposed on a second layer in a manner stacked on the first layer and orthogonal to the first roller 1411.

[0102] like Figure 6A As shown, the conveyed steel cord 12 can change its conveying direction to the Z-axis direction by contacting the surfaces of the first roller 1411 and the second roller 1412, thereby aligning the conveying directions. Figure 6A , Figure 6B Only one steel cord 12 is shown, but two or more steel cords 12 can also be supplied to the first roller 1411 in the same way and the conveying direction can be changed to the Z-axis direction by the second roller 1412 and two or more steel cords 12 can be arranged along the X-axis.

[0103] Next, for example, Figure 6C As shown, for example, the steel cords 12 constituting the steel cord group 2 can be arranged by guiding two or more steel cords 12 into the slits 1421 pre-cut on the guide plate 142. Alternatively, the position can be further corrected and arranged using the grooved roller 15 as needed.

[0104] In the manufacturing method of the rubber composite of this embodiment, a certain tension is applied to the steel cord 12. Therefore, the position alignment of the steel cord 12 can be easily performed during the arrangement process.

[0105] Therefore, as Figure 6CAs shown, the size of the slit 1421 engraved on the guide plate 142 used in the arrangement process 102 is preferably selected in a manner that is sufficiently large compared to the size of the steel cord 12, such that the steel cord 12 does not typically contact the surface of the slit 1421. The same applies to the grooves formed on the grooved roller 15.

[0106] (4) Rubber composite manufacturing process

[0107] In the rubber composite manufacturing process 103, a rubber composite can be manufactured by embedding steel cord groups, i.e., two or more steel cords, in rubber.

[0108] Specifically, for example, by using calendering rolls 17 to arrange steel cord groups 2, i.e., two or more steel cords 12, between rubber 16 for calendering, a rubber composite 40 can be manufactured.

[0109] (5) Tension adjustment process

[0110] The manufacturing method of the rubber composite in this embodiment may, as needed, include a tension adjustment step 104 between the pulling step 101 and the arranging step 102 to adjust the tension of the steel cord 12.

[0111] In this way, by implementing the tension adjustment process, the tension of the steel cord supplied to the arrangement process can be easily controlled within the desired range.

[0112] In the tension adjustment process 104, the tension of the steel cord is preferably adjusted, for example, by changing the position of the tension adjustment roller that is in contact with the conveyed steel cord.

[0113] By changing the position of the tension adjusting roller that contacts the conveyed steel cord 12, the tension of the steel cord 12 can be easily controlled. Furthermore, by using the tension adjusting roller, surface defects in the steel cord 12 can be suppressed.

[0114] For example, Figure 1A As shown, the tension of the steel cord 12 can also be adjusted using a first tension adjusting device 131 having a rotating shaft 1311, a tension adjusting arm 1312 and a first tension adjusting roller 1313.

[0115] In the first tension adjusting device 131, the tension adjusting arm 1312 and the first tension adjusting roller 1313 mounted on the tension adjusting arm 1312 can move along the bidirectional arrow B about the rotation axis 1311. Therefore, by bringing the first tension adjusting roller 1313 into contact with the steel cord 12 pulled out from the drum 11 and controlling the position of the first tension adjusting roller 1313, the tension of the steel cord 12 can be adjusted.

[0116] It should be noted that, in Figure 1AThe illustration shows an example of providing a first tension adjusting device 131 for each steel cord 12, but is not limited to this method. The tension can also be adjusted uniformly using the first tension adjusting device 131 for two or more steel cords drawn from a single drum 11.

[0117] The tension adjustment process can also involve more than two steps. That is, such as... Figure 1B As shown, the tension adjustment process 104 may also include at least a first tension adjustment process 1041 and a second tension adjustment process 1042.

[0118] exist Figure 1B In the first tension adjustment step 1041, the tension of the steel cord 12 pulled from the drum 11 is adjusted using the aforementioned first tension adjustment device 131. It should be noted that... Figure 1B In this process, a first tension adjusting device 131 is used to adjust the tension of two or more steel cords 12, but it is not limited to this method; it can also be combined with... Figure 1A Similarly, a first tension adjustment device 131 is provided for each steel cord 12.

[0119] In addition, Figure 1B In the process, the tension of each steel cord 12 is further adjusted using a second tension adjusting device 132. The second tension adjusting device 132 has... Figure 1B The second tension adjusting roller shown is configured such that it can move up and down along the double-headed arrow C in the figure. Therefore, the second tension adjusting device 132 can control the tension of the steel cord 12 by controlling the position of the second tension adjusting roller.

[0120] Thus, by having at least a first tension adjustment step 1041 and a second tension adjustment step 1042 as tension adjustment step 104, that is, by implementing the tension adjustment step in two or more steps, the tension of the steel cord 12 can be controlled more precisely.

[0121] exist Figure 1B The example shown is an example of adjusting the tension of the steel cord 12 through two processes, but it is not limited to this method. The tension of the steel cord 12 can also be adjusted through three or more processes.

[0122] [Tire manufacturing methods]

[0123] Next, the tire manufacturing method of this embodiment will be described.

[0124] The tire manufacturing method of this embodiment includes a tire manufacturing step of manufacturing a tire using a rubber composite obtained by the above-described rubber composite manufacturing method.

[0125] Rubber composites can be used, for example, in the belt layer and carcass of tires. Therefore, by placing a rubber composite manufactured by the above-described method in, for example, the location of a belt layer or carcass and combining it with other components, a tire can be manufactured.

[0126] Apart from using the aforementioned rubber composite, it can be manufactured using conventional tire manufacturing methods, therefore detailed explanations are omitted.

[0127] The tire manufacturing method of this embodiment can be used to manufacture the tire described later.

[0128] According to the tire manufacturing method of this embodiment, since a rubber composite obtained by the above-described rubber composite manufacturing method is used, the manufactured tire can be made lighter. Furthermore, according to the above-described rubber composite manufacturing method, defects and coating peeling on the surface of the steel cord 12 can be suppressed during the manufacturing of the rubber composite. Therefore, the adhesion between the steel cord 12 and the rubber 41 is excellent, and the durability of the tire using this rubber composite 40 can also be improved.

[0129] [Rubber Composite]

[0130] Next, the rubber composite of this embodiment will be described.

[0131] The rubber composite of this embodiment can be manufactured using the rubber composite manufacturing method described above. Therefore, some descriptions of matters already explained are omitted.

[0132] like Figure 7 As shown, the rubber composite 40 of this embodiment has two or more steel cords 12, namely steel cord groups 2, and rubber 41 in which the steel cord groups 2 are embedded. It should be noted that, as described above, single-strand steel cords can be used as the steel cords 12.

[0133] Furthermore, in the cross-section of the rubber composite 40 perpendicular to the length direction of the steel cords 12, the steel cords 12 constituting the steel cord group 2 are arranged in a row. Additionally, in the aforementioned cross-section, the average deviation of the position of the steel cords in the thickness direction of the rubber composite 40 can be 0.016 mm or less.

[0134] The components of the rubber composite of this embodiment will be described below.

[0135] (1) Regarding the various components of the rubber composite

[0136] (steel cord)

[0137] As described above, the steel cord 12 is a single-strand steel cord, i.e., a single steel wire. Preferably, the steel cord 12 is not twisted along its length. That is, the steel cord 12 is preferably a straight steel cord.

[0138] The steel cord 12 preferably has a circular cross-section perpendicular to its length direction. The term "circular" here does not refer to a circle in a strictly geometric sense, but rather includes shapes that can be considered circular within tolerance limits.

[0139] The diameter D of the steel cord 12 is not particularly limited, but is preferably 0.20 mm or more and 0.45 mm or less, and more preferably 0.25 mm or more and 0.40 mm or less.

[0140] By making the cord diameter D of the steel cord 12 0.45 mm or less, the thickness of the rubber composite 40 can be particularly suppressed, resulting in a lighter rubber composite 40 and tires using the rubber composite 40. Furthermore, by making the cord diameter of the steel cord 0.45 mm or less, the number of steel cords that can be embedded in the rubber composite can be significantly increased. Therefore, the handling performance and ride comfort of passenger cars and other vehicles equipped with tires using this rubber composite can be improved. In addition, compared to stranded steel cords with larger cord diameters, the length of the steel cord wound on the spool is longer, thus reducing the frequency of spool changes during rubber composite manufacturing and increasing productivity.

[0141] Furthermore, by making the cord diameter D of the steel cord 12 0.20 mm or more, it is possible to have sufficient breaking load, thereby significantly improving the strength of the rubber composite 40 and the tire using the rubber composite 40.

[0142] The material of the steel cord 12 is not particularly limited, for example, Figure 5 As shown, the steel cord may have a configuration in which steel wires 31 are disposed and a coating 32 is disposed on the surface of the steel wires 31.

[0143] High-carbon steel wire can be preferred for steel wire 31.

[0144] Furthermore, while the coating 32 can be configured to consist of only Cu (copper) and Zn (zinc) metal components, such as a brass coating, it may also contain other metal components besides Cu and Zn. For example, the coating 32 may also contain one or more elements selected from Co (cobalt) and Ni (nickel) as metal components.

[0145] That is, the steel cord can have a brass coating on its surface, for example, containing Cu and Zn. Furthermore, the aforementioned brass coating may also contain one or more elements selected from Co and Ni. It should be noted that the brass coating can, for example, be applied to the surface of the steel wire as described above.

[0146] By applying a brass coating containing Cu and Zn to the steel cord, when the steel cord is coated with rubber and vulcanized to form a rubber composite or tire, a Cu2S-containing adhesive layer can be formed closer to the rubber side than at the steel cord-rubber interface. It should be noted that Zn promotes the formation of Cu2S. By forming this adhesive layer, the adhesion between the steel cord and rubber can be improved, enabling the production of rubber composites and tires with exceptional durability.

[0147] Furthermore, Co and Ni have a greater tendency to ionize than Zn. Therefore, by including one or more elements selected from Co and Ni in the brass coating, these elements can function by sacrificing corrosion protection, or by increasing the synthesis potential of Cu and Zn, thereby improving the corrosion resistance of the brass coating. As a result, the adhesive strength between steel cord and rubber can be further improved, and the durability of rubber composites and tires can be further enhanced.

[0148] (rubber)

[0149] The rubber 41 of the rubber composite 40 can be manufactured by molding the rubber composition and vulcanizing it as needed.

[0150] The specific composition of the rubber can be selected based on the application of the tire using the rubber composite of this embodiment, the required properties of the tire, etc., and is not particularly limited. The rubber may, for example, contain rubber components, sulfur, and vulcanization accelerators.

[0151] The rubber component preferably contains more than 60% by mass of, for example, one selected from natural rubber (NR) and isoprene rubber (IR), more preferably more than 70% by mass, and even more preferably 100% by mass.

[0152] This is because by making the proportion of one or more rubbers selected from natural rubber and isoprene rubber in the rubber component 60% by mass or more, the breaking strength of the rubber composite and tire can be improved, and therefore it is preferred.

[0153] As a rubber component used in combination with natural rubber and isoprene rubber, examples include one or more selected from styrene-butadiene rubber (SBR), butadiene rubber (BR), ethylene-propylene-diene rubber (EPDM), chloroprene rubber (CR), butyl rubber (IIR), and nitrile rubber (NBR).

[0154] As for sulfur, there are no particular limitations; for example, sulfur commonly used as a vulcanizing agent in the rubber industry can be used.

[0155] The sulfur content of the rubber is not particularly limited, but it is preferably set to be, for example, 5 parts by mass or more and 8 parts by mass or less per 100 parts by mass of the rubber component.

[0156] This is because by making the proportion of sulfur 5 parts by mass or more relative to 100 parts by mass of the rubber component, the crosslinking density of the obtained rubber can be increased, and in particular, the adhesive strength between the steel cord and the rubber can be improved. Furthermore, by making the proportion of sulfur 8 parts by mass or less relative to 100 parts by mass of the rubber component, the sulfur can be dispersed particularly uniformly within the rubber, and blooming can be suppressed, which is therefore preferable.

[0157] The vulcanization accelerator is not particularly limited, but sulfonamide accelerators such as N,N'-dicyclohexyl-2-benzothiazolylsulfenamide, N-cyclohexyl-2-benzothiazolylsulfenamide, N-tert-butyl-2-benzothiazolylsulfenamide, and N-oxydiethylene-2-benzothiazolylsulfenamide are preferred. Alternatively, thiazole accelerators such as 2-mercaptobenzothiazolium and di(2-benzothiazolium) disulfide, tetrabenzylthiuram disulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetra(2-ethylhexyl)thiuram disulfide, and tetramethylthiuram monosulfide may be used as desired.

[0158] The rubber composition used in the rubber composite of this embodiment can be manufactured by mixing these components using conventional methods and then heating and extruding them.

[0159] In addition, the rubber of the rubber composite of this embodiment preferably contains one or more elements selected from cobalt and cobalt-containing compounds.

[0160] As compounds containing cobalt, examples include organic cobalt acids and inorganic cobalt acids.

[0161] As an organic cobalt acid, one or more selected from cobalt naphthenate, cobalt stearate, cobalt neodecanoate, cobalt rosinate, cobalt tert-carbonate, and cobalt tallowate are preferred. It should be noted that the organic cobalt acid can be a complex salt obtained by replacing a portion of an organic acid with boric acid.

[0162] As an inorganic cobalt acid, one or more selected from cobalt chloride, cobalt sulfate, cobalt nitrate, cobalt phosphate, and cobalt chromate may be preferred.

[0163] In particular, the rubber in the rubber composite of this embodiment more preferably contains cobalt organic acid. This is because the presence of cobalt organic acid can significantly improve the initial adhesive properties between the steel cord and the rubber. It should be noted that the initial adhesive properties refer to the adhesive properties between the steel cord and the rubber immediately after vulcanization, such as during the manufacture of the rubber composite or tire.

[0164] Furthermore, according to the inventors' research based on the present invention, by adding cobalt to the rubber, the proportion of Cu2S in the adhesive layer can be increased, thereby improving the adhesive strength between the steel cord and the rubber. This tendency becomes more pronounced when cobalt organic acid is used as the added cobalt. Therefore, the rubber composite of this embodiment preferably contains cobalt, particularly cobalt organic acid, thereby enabling the production of rubber composites and tires with particularly excellent durability.

[0165] In addition to the aforementioned rubber components, sulfur, vulcanization accelerators, cobalt, etc., rubber may also contain optional components. Rubber may also contain known rubber additives such as reinforcing agents (carbon black, silica, etc.), waxes, and anti-aging agents.

[0166] (2) Regarding the structure of rubber composites

[0167] like Figure 7 As shown, the rubber composite 40 of this embodiment may have two or more steel cords 12, namely steel cord group 2, and rubber 41 in which the steel cord group 2 is embedded. Figure 7 In the diagram, the Y-axis direction, perpendicular to the paper, is the length direction of the steel cord 12. Figure 7 In the middle, two or more steel cords 12 constituting the steel cord group 2 are arranged in a row along the X-axis direction, which is equivalent to the width direction of the rubber composite 40. Figure 7 In the figure, the Z-axis direction is the thickness direction of the rubber composite 40.

[0168] The rubber composite 40 of this embodiment can suppress the positional deviation of the steel cords 12 constituting the steel cord group 2 in the thickness direction of the rubber composite 40. Furthermore, in this embodiment, the average value of the positional deviation of the steel cords 12 constituting the steel cord group 2 in the thickness direction of the rubber composite 40 is preferably 0.016 mm or less, more preferably 0.015 mm or less.

[0169] The average deviation of the two or more steel cords 12 constituting the steel cord group 2 in the thickness direction of the rubber composite 40 can be expressed in a cross section of the rubber composite 40 perpendicular to the length direction of the steel cords, for example... Figure 7 The cross-section shown is measured and calculated using the steps described below.

[0170] In the cross section of the rubber composite 40 perpendicular to the length direction of the steel cord 12, a measurement area is selected in which 10 steel cords 12A to 12J are arranged continuously.

[0171] Then, on the flat surface 401, the first surface 40A of the rubber composite 40, which includes the aforementioned measurement area, is positioned in contact with the flat surface 401. At this time, it is preferable to place a weight (not shown) on the second surface 40B, located on the side of the rubber composite 40 opposite to the first surface 40A, to press the rubber composite 40 onto the flat surface 401. The weight of the weight is not particularly limited, but it is preferable to have a weight of 0.05 kg / mm² per unit area of ​​the surface of the rubber composite 40 on which the weight is applied. 2 The method of setting up heavy objects.

[0172] In the cross-section of the rubber composite 40 perpendicular to the length direction of the steel cord 12, a line is drawn from the section located in the width direction, i.e. Figure 7 The center O of the steel cord 12A on the first end 40C side, one of the two ends in the X-axis direction. 12A The reference line 402 is crossed. The reference line 402 is drawn out in a form that is parallel to the flat surface 401.

[0173] Next, the deviation of the position of the steel cords 12B to 12J, other than the reference steel cord 12A, along the thickness direction of the rubber composite 40 was measured.

[0174] The deviation of each steel cord 12 is determined by the following method: measuring along the thickness direction of the rubber composite 40, i.e. Figure 7 The thickness direction is calculated by subtracting the radius R of the steel cord 12 from the maximum length between the reference line 402 and the end of each steel cord 12 in the Z-axis direction. It should be noted that since the Z-axis is perpendicular to the flat surface 401 and the reference line 402, the thickness direction can also be referred to as the direction perpendicular to the reference line 402.

[0175] The deviation range W of steel cord 12B 12B In the case of measuring the maximum length L of the distance between the reference line 402 and the outer periphery of the steel cord 12B along the thickness direction of the rubber composite 40, i.e., the Z-axis direction, the maximum length L is determined. 12B Subtract the radius R of steel cord 12 to calculate the value. Similarly, for each steel cord 12C to 12J, the value can be calculated based on the maximum length L. 12C ~L 12J The deviation range is calculated based on the radius R of steel cord 12. The deviation range of steel cord 12A is 0.

[0176] The average deviation of each steel cord 12A to 12J measured is the average deviation of the position of the steel cord 12 in the thickness direction of the rubber composite 40.

[0177] When the average deviation of the position of the steel cord 12 in the thickness direction of the rubber composite 40 is less than 0.016 mm, the distribution width of the steel cord 12 in the thickness direction of the rubber composite 40 can be sufficiently suppressed.

[0178] As described above, the thickness T of the rubber composite 40 is a value obtained by adding the distribution width W of the steel cords 12 in the thickness direction of the rubber composite 40 to a rubber thickness predetermined in a manner that allows the steel cords 12 to be embedded. Therefore, by ensuring that the average deviation of the position of the steel cords 12 in the thickness direction of the rubber composite 40 is less than 0.016 mm, the thickness of the rubber composite 40 can be suppressed, and the rubber composite 40 and the tire using the rubber composite 40 can be made lighter.

[0179] However, if the average value of the deviation of the position of the steel cord 12 in the thickness direction of the rubber composite 40 is excessively suppressed, productivity may decrease. Therefore, the average value of the aforementioned deviation is preferably 0.010 mm or more, and more preferably 0.012 mm or more.

[0180] The number of steel cords 12 in the rubber composite 40 of this embodiment is not particularly limited, and can be selected according to the rubber composite 40 and the performance requirements of the tire using the rubber composite 40. Here, the number of steel cords present in every 5cm width of the rubber composite 40 in a cross section perpendicular to the length direction of the steel cords 12 is defined as the density. In this case, the density is preferably 60 cords / 5cm or more and 100 cords / 5cm or less, and more preferably 60 cords / 5cm or more and 95 cords / 5cm or less.

[0181] By setting the density of the rubber composite in this embodiment to 60 cords / 5cm or more, the durability of the rubber composite and the tires using the rubber composite can be significantly improved. By setting it to 100 cords / 5cm or less, the amount of rubber between the cords can be ensured, which can improve the ride comfort of the tires using the rubber composite.

[0182] [tire]

[0183] Next, based on Figure 8 The tire in this embodiment will be described.

[0184] The tire of this embodiment may include the rubber composite described above.

[0185] Figure 8 A cross-sectional view of a plane perpendicular to the circumferential direction of the tire 50 of this embodiment is shown. Figure 8 In the image, only the left side of the CL (center line) is shown, but the same structure is continuously present on the right side of the CL, which is the axis of symmetry.

[0186] like Figure 8 As shown, the tire 50 has a tread portion 51, a sidewall portion 52, and a bead portion 53.

[0187] The tread portion 51 is the part that contacts the road surface. The bead portion 53 is located on the inner diameter side of the tire 50, compared to the tread portion 51. The bead portion 53 is the part that contacts the rim of the vehicle's wheel. The sidewall portion 52 connects the tread portion 51 and the bead portion 53. When the tread portion 51 is impacted by the road surface, the sidewall portion 52 undergoes elastic deformation to absorb the impact.

[0188] Tire 50 has an inner liner 54, a carcass 55, a belt layer 56, and bead wires 57.

[0189] The inner liner 54 is made of rubber, which seals the space between the tire 50 and the wheel.

[0190] The carcass 55 forms the skeleton of the tire 50. The carcass 55 is made of organic fibers such as polyester, nylon, and rayon, or steel cord, and rubber. The aforementioned rubber composite 40 may also be used in the carcass 55.

[0191] The bead wire 57 is located in the bead portion 53. The bead wire 57 bears the tensile force acting on the tire carcass.

[0192] The belt layer 56 secures the tire carcass 55 and increases the rigidity of the tread 51. Figure 8 In the example shown, tire 50 has two belt layers 56.

[0193] in addition, Figure 8 The tire 50 shown has two belt layers 56, for example, belt layers 56 can use Figure 7 The rubber composite 40 shown above.

[0194] exist Figure 8 The diagram shows a tire 50 with two belt layers 56, but it is not limited to this method. The tire of this embodiment may also have one or more belt layers 56.

[0195] The tire of this embodiment is lightweight because it uses the aforementioned rubber composite 40. Furthermore, the rubber composite suppresses surface defects in the steel cords and coating peeling. Therefore, the adhesion between the steel cords and the rubber is excellent, and the durability of the tire using this rubber composite is also improved.

[0196] The embodiments have been described in detail above, but are not limited to specific embodiments. Various modifications and alterations can be made within the scope of the claims.

[0197] Example

[0198] The following are specific examples for illustration, but the present invention is not limited to these examples.

[0199] (Evaluation Method)

[0200] First, the evaluation method for the steel cord and rubber composites prepared in the following experimental examples will be explained.

[0201] (1) The diameter D of the steel cord

[0202] The diameter of the steel cord was determined using the micrometer method according to JIS G 3510 (1992).

[0203] Specifically, the diameter D of the steel cord was measured using a micrometer at three cross-sections perpendicular to its length, and the average value was calculated. The measurements were taken at three cross-sections spaced 5 cm apart along the length of the steel cord 12.

[0204] (2) The ratio of the tension of each steel cord to the breaking load of each steel cord

[0205] (2-1) Breaking load of each steel cord

[0206] Using a universal testing machine (manufactured by Shimadzu Corporation, model: AGS-H 10kN), a load is applied along the length of the steel cord, and the load applied to the steel cord at the time of breakage is taken as the breaking load of each steel cord.

[0207] (2-2) Tension of each steel cord

[0208] A three-point roller mechanical tension meter (manufactured by Imada Co., Ltd., model: DX2-200) was used to measure the relationship between the operating and control conditions of the tension regulating device installed in the production line and the tension of the steel cord 12 supplied to the arranging process. That is, the tension value applied to the steel cord supplied to the arranging process can be calculated based on the operating and control conditions of the tension regulating device. Then, for each experimental example, the operating and control conditions of the tension regulating device were set in such a way that the tension value of each steel cord reaches the desired value.

[0209] It should be noted that, in the following experimental examples, the tension applied to the steel cord 12 was measured multiple times before and after the manufacture of the rubber composites. The results show that the deviation between the measured values ​​and the calculated values ​​is very small. Specifically, for the tension of the steel cord, the deviation between the measured values ​​and the calculated values ​​is within ±2.5%.

[0210] (2-3) The ratio of the tension of each steel cord to the breaking load of each steel cord

[0211] Based on the tension and breaking load of each steel cord obtained in the above manner, the ratio of the tension to the breaking load of each steel cord is calculated using the following formula. The results are shown in the "Ratio of Tension to Breaking Load of Steel Cord" column in Tables 1 and 2.

[0212] (The ratio of the tension of each steel cord to the breaking load of each steel cord) = (Tension of each steel cord) ÷ (Breaking load of each steel cord) × 100

[0213] (3) The average value of the deviation of the steel cord position in the thickness direction of the rubber composite.

[0214] like Figure 7 As shown, the measurement area in which 10 steel cords 12A to 12J are continuously arranged in the cross section of the rubber composite 40 made in each experimental example, perpendicular to the length direction of the steel cord 12.

[0215] Then, on the flat surface 401, the first surface 40A of the rubber composite 40, which includes the aforementioned measurement area, is positioned in contact with the flat surface 401. At this time, on the second surface 40B of the rubber composite 40, located on the side opposite to the first surface 40A, a density of 0.05 kg / mm² is applied per unit area. 2 A weight is placed to press the rubber composite 40 onto the flat surface 401. The weight is a plate-shaped object with the same area as the second surface 40B on the side opposite to it. It should be noted that the test specimen of the rubber composite contains 10 steel cords 12A to 12J, cut into squares with the first surface 40A and the second surface 40B as the basis for the test.

[0216] In the cross-section of the rubber composite 40 perpendicular to the length direction of the steel cord, a line is drawn from the section located in the width direction, i.e. Figure 7 The center O of the steel cord 12A on the first end 40C side, one of the two ends in the X-axis direction. 12A The reference line 402 is crossed. The reference line 402 is drawn in a manner parallel to the flat surface 401.

[0217] Next, the deviation of steel cords 12B to 12J, other than the reference steel cord 12A, was measured along the thickness direction of the rubber composite 40.

[0218] The deviation of each steel cord 12 was determined as follows: Measured along the thickness direction of the rubber composite 40, i.e. Figure 7 The maximum length between the reference line 402 and the end of each steel cord 12 in the Z-axis direction is calculated by subtracting the radius R of the steel cord 12.

[0219] The deviation range W of steel cord 12B 12B In the case of measuring the maximum length L of the distance between the reference line 402 and the outer periphery of the steel cord 12B along the thickness direction of the rubber composite 40, i.e., the Z-axis direction. 12B Subtract the radius R of steel cord 12 to calculate the value. Similarly, for each steel cord 12C to 12J, calculate the value based on the maximum length L. 12C ~L 12J The deviation range is calculated based on the radius R of the steel cord 12. The deviation range of the steel cord 12A is 0. It should be noted that the radius R is half the value of the cord diameter D mentioned above.

[0220] The average value of the deviation amplitude of the positions of each steel cord 12A to 12J was taken as the average value of the deviation amplitude of the position of the steel cord 12 in the thickness direction of the rubber composite 40. The results are shown in the column "Deviation amplitude of the position of the steel cord in the thickness direction of the rubber composite" in Tables 1 and 2.

[0221] (4) Defects on the coating surface

[0222] A 5cm steel cord was randomly selected from the rubber composites prepared in each experimental example, and its appearance was confirmed using an optical microscope at 100x magnification. Defects such as abrasion in the coating of the steel cord were evaluated as "present". Defects without such features were evaluated as "absent".

[0223] (5) Weight index

[0224] The weight of the rubber composites prepared in each experimental example was measured. In Experiment 1, the weight of the rubber composites from Examples 1-6 was set to 100; in Experiment 2, the weight of the rubber composites from Examples 2-4 was set to 100. The weight of the rubber composites prepared in each experimental example was expressed as an index. It should be noted that test pieces of the rubber composites in each experimental example were prepared with a width and depth of 50 mm, and the weight of the rubber composites in each experimental example was measured. The width of the rubber composite was... Figure 7 The length along the X-axis refers to the direction in which two or more steel cords are arranged. Additionally, the depth of the rubber composite is... Figure 7 The length along the Y-axis corresponds to the length of the steel cord in the longitudinal direction. The test pieces of the rubber composites in each experimental example contain a number of steel cords corresponding to the density.

[0225] (Regarding the experimental example)

[0226] The experimental conditions are described below.

[0227] [Experimental Example 1]

[0228] The rubber composite was manufactured through the following steps. Examples 1-1 to 1-3 are exemplary cases, and Examples 1-4 to 1-6 are comparative cases.

[0229] [Experiment Example 1-1]

[0230] (Preparation process for steel cord and roller)

[0231] The steel cord is prepared with a circular cross-section before processing. The steel cord before processing has a brass coating with a metallic composition of Cu and Zn on the surface of the high carbon steel wire.

[0232] Then, the unprocessed steel cord is fed to the rolling mill so that the cord diameter is 0.30 mm and the cross-section perpendicular to the length direction is... Figure 5 The steel cord is processed in a circular manner as shown. The diameter D of the resulting steel cord is measured using the steps described above, and the result is 0.30 mm. Figure 5 As shown, the obtained steel cord has a steel wire 31 as a high carbon steel wire and a coating 32 as a brass coating composed of Cu and Zn covering the steel wire 31.

[0233] The two obtained single-strand steel cords are wound onto a single spool, ready for use in manufacturing the rubber composite. It should be noted that the winding pitch of the steel cords on each spool is 0.6 mm.

[0234] The winding pitch P is determined according to the following steps. For example... Figure 3 As shown, within the measurement area 123, excluding the range of 10 cm from the first inner side 111A and the second inner side 111B of the flange 111 of the drum 11, the number of 10 turns of the first steel cord 121 is photographed.

[0235] Then, measure along the central axis CA of the roll 11 (refer to...) Figure 4 The winding pitch P is calculated by dividing the length of 10 turns of the first steel cord 121 by 10. The same determination is made in the other experimental examples below.

[0236] (Roll setting process)

[0237] In Experiment 1-1, according to Figure 1B The steps of the method for manufacturing the rubber composite shown are as follows: manufacturing the rubber composite. Then, in the roll setting process, 40 prepared rolls 11, i.e., roll group 1A, are set in the steel cord supply device 10.

[0238] (Pull-out process)

[0239] like Figure 1BAs shown, in the pulling-out process 101, the steel cord supply device 10 simultaneously pulls out a total of 80 steel cords 12 wound on the 40 prepared drums 11, i.e., drum group 1A, and delivers them to the arrangement process 102 described later.

[0240] The number of rollers used is less than in Experimental Examples 1-5 described later. Therefore, there is greater flexibility in the location of the rollers, allowing them to be set such that the angle between the steel cord supplied to the pre- and post-arrangement processes, i.e., the inlet angle θ, is 42 degrees or more and 48 degrees or less. It should be noted that in Tables 1 and 2, when the inlet angle column is described as "42-48", the values ​​indicated by the "-" sign refer to the lower and upper limits of the inlet angle. Furthermore, the inlet angle refers to a range including these lower and upper limits. Therefore, "42-48" above refers to an inlet angle of 42 degrees or more and 48 degrees or less.

[0241] (Tension adjustment process)

[0242] When supplied to the arrangement process 102, utilize Figure 1B The first tension adjusting device 131 and the second tension adjusting device 132 shown are adjusted so that the ratio of the tension of the steel cord 12 to the breaking load of each steel cord is the value shown in Table 1. That is, a tension adjusting process 104, which includes a first tension adjusting process 1041 and a second tension adjusting process 1042, is performed between the pulling-out process 101 and the arranging process 102. The first tension adjusting device 131 and the second tension adjusting device 132 have already been described, so their description is omitted here.

[0243] (Arrangement of processes)

[0244] In the arrangement process 102, the 80 steel cords 12 pulled out from the drum 11 in the pulling process 101 are arranged in a row in a cross section perpendicular to the length direction of the steel cords 12.

[0245] Specifically, in the arrangement process 102, using Figure 6A , Figure 6B The composite roller 141 shown pulls 80 steel cords 12, i.e., steel cord group 2, along a specified direction. Then, it is fed into... Figure 6C The slits 1421 pre-etched on the guide plate 142 are used for arrangement. In addition, the position of the steel cord 12 is further corrected and arranged by the grooved roller 15 disposed on the downstream side of the conveying direction of the steel cord 12.

[0246] The slot 1421 engraved on the guide plate 142 used in the arrangement process 102, and the size of the groove formed on the grooved roller 15 are selected in such a way that they are large enough compared to the size of the steel cord 12, and the steel cord 12 generally does not contact the surface of the slot 1421 or the groove.

[0247] (Rubber composite manufacturing process)

[0248] In the rubber composite manufacturing process 103, 80 steel cords, namely steel cord group 2, are embedded in the rubber to manufacture the rubber composite.

[0249] Specifically, using calendering rolls 17, 80 steel cords 12, i.e. steel cord group 2, are arranged between rubber 16 for calendering to produce rubber composite 40.

[0250] The aforementioned rubber 16 is manufactured from a rubber composition comprising rubber components and additives. The rubber composition comprises 100 parts by mass of natural rubber as a rubber component. Additionally, the rubber composition contains additives in proportions relative to 100 parts by mass of the rubber component, 60 parts by mass of carbon black, 6 parts by mass of sulfur, 1 part by mass of a vulcanization accelerator, 10 parts by mass of zinc oxide, and 1 part by mass of cobalt stearate as an organic cobalt acid.

[0251] As shown in Table 1, the number of steel cords present in every 5cm width of the rubber composite in a cross-section perpendicular to the length direction of the steel cords is set as the density, with the steel cords arranged at a density of 80 cords / 5cm. The thickness T of the rubber composite is a value obtained by adding the distribution width W of the thickness direction of two or more steel cords arranged in the rubber composite to the rubber thickness predetermined in a way that allows the steel cords to be embedded.

[0252] The evaluation results are shown in Table 1.

[0253] [Experimental Examples 1-2, 1-3]

[0254] The tension adjustment device was set so that the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord was as shown in Table 1. Apart from the above, a rubber composite was manufactured in the same manner as in Experimental Example 1-1, and its performance was evaluated. The evaluation results are shown in Table 1.

[0255] [Experimental Examples 1-4]

[0256] The tension adjustment device was set so that the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord was as shown in Table 1. Apart from the above, a rubber composite was manufactured in the same manner as in Experimental Example 1-1, and its performance was evaluated. The evaluation results are shown in Table 1.

[0257] [Experimental Examples 1-5]

[0258] One steel cord is wound onto each drum. It should be noted that the winding pitch of the steel cord on each drum is 0.6 mm.

[0259] In Experiment Examples 1-5, according to Figure 2 The steps of the method for manufacturing the rubber composite shown are as follows: The rubber composite is manufactured. Then, the steel cord supply device is set such that the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord is as shown in Table 1.

[0260] Eighty of the aforementioned drums, i.e. drum sets, are installed in the steel cord supply device in such a way that they can supply the same number of steel cords as those in other experimental examples.

[0261] It should be noted that in order to set up 80 rolls, such as Figure 2 The steel cord supply device 20 shown is modified in advance to increase the number of ports.

[0262] Except for the aspects mentioned above, the rubber composite was manufactured in the same manner as in Experimental Example 1-1. The resulting rubber composite was then evaluated. The evaluation results are shown in Table 1.

[0263] [Experimental Examples 1-6]

[0264] Instead of single-strand steel cord, a stranded steel cord with a 1×2 structure, formed by twisting two steel cords used in Experimental Example 1-1, was used. Additionally, one steel cord was wound onto each drum. It should be noted that the winding pitch of the steel cord on each drum was 1.2 mm.

[0265] Then, the tension adjustment device is set such that the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord is the value shown in Table 1.

[0266] The density of the manufactured rubber composite is 40 strands / 5cm.

[0267] Except for the aspects mentioned above, the rubber composite was manufactured in the same manner as in Experimental Example 1-1. The resulting rubber composite was then evaluated. The evaluation results are shown in Table 1.

[0268] [Table 1]

[0269]

[0270] In Experimental Examples 1-1 to 1-3, 80 steel cords were supplied to the manufacturing process. However, it was confirmed that, compared with Experimental Example 1-5, the number of rolls used to supply the steel cords could be suppressed.

[0271] In Experimental Examples 1-1 to 1-3, as shown in Table 1, a rubber composite was manufactured by making the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord between 6.0% and 9.0%.

[0272] Furthermore, it can be confirmed that, compared with the rubber composites of Experimental Examples 1-4 which used rolls that did not meet the above requirements, the rubber composites obtained in Experimental Examples 1-1 to 1-3 above can suppress the deviation of the position of the steel cord in the thickness direction of the rubber composite. The results also confirm that, compared with the rubber composites obtained in Experimental Examples 1-4, the rubber composites obtained in Experimental Examples 1-1 to 1-3 can also suppress the weight index.

[0273] Furthermore, in Experiments 1-5, the number of rollers used was greater than in Experiments 1-1 to 1-3. Therefore, it can be confirmed that the degree of freedom in setting up the rollers decreased, and the distribution of the feed angle increased. The results confirm that the coating of the steel cord in the obtained rubber composite exhibits defects.

[0274] In Experiments 1-6, stranded wire with a 1×2 structure was used as the steel cord. Therefore, although the number of rolls could be reduced, the cord diameter of the steel cord itself increased, thus confirming that the weight index increased.

[0275] [Experimental Example 2]

[0276] The rubber composite was manufactured through the following steps. Examples 2-1 to 2-3 are exemplary cases, and Examples 2-4 and 2-5 are comparative cases.

[0277] [Experiment Example 2-1]

[0278] (Preparation process for steel cord and roller)

[0279] The steel cord is prepared with a circular cross-section before processing. The steel cord before processing has a brass coating with a metallic composition of Cu and Zn on the surface of the high carbon steel wire.

[0280] Then, the steel cord before processing is fed to the rolling mill so that the cord diameter is 0.40 mm and the cross-section perpendicular to the length direction is as follows. Figure 5 The steel cord is processed in a circular manner as shown. The diameter D of the resulting steel cord is measured using the steps described above, and the result is 0.40 mm. Figure 5 As shown, the obtained steel cord has a steel wire 31 as a high carbon steel wire and a coating 32 as a brass coating composed of Cu and Zn covering the steel wire 31.

[0281] The two obtained single-strand steel cords are wound onto a single spool, ready for use in manufacturing the rubber composite. It should be noted that the winding pitch of the steel cords on each spool is 1.2 mm.

[0282] The obtained rolls were evaluated as described above. The evaluation results are shown in Table 2.

[0283] (Roll setting process)

[0284] In Experiment 2-1, according to Figure 1B The steps of the method for manufacturing the rubber composite shown are as follows: manufacturing the rubber composite. Then, in the roll setting process, 40 prepared rolls 11, i.e., roll group 1A, are set in the steel cord supply device 10.

[0285] (Pull-out process)

[0286] like Figure 1B As shown, in the pulling-out process 101, the steel cord supply device 10 simultaneously pulls out a total of 80 steel cords 12 wound on the 40 prepared drums 11, i.e., drum group 1A, and delivers them to the arrangement process 102 described later.

[0287] The number of rollers used is less than that in Experimental Examples 2-4 described later. Therefore, there is a high degree of freedom in the location of the rollers, and they can be set in such a way that the angle between the steel cords supplied to the front and back of the arrangement process, i.e., the inlet angle θ, is 42 degrees or more and 48 degrees or less.

[0288] (Tension adjustment process)

[0289] When supplied to the arrangement process 102, utilize Figure 1B The first tension adjusting device 131 and the second tension adjusting device 132 shown are adjusted so that the ratio of the tension of the steel cord 12 to the breaking load of each steel cord is the value shown in Table 2. That is, a tension adjusting process 104, which includes a first tension adjusting process 1041 and a second tension adjusting process 1042, is performed between the pulling-out process 101 and the arranging process 102. The first tension adjusting device 131 and the second tension adjusting device 132 have already been described, so their description is omitted here.

[0290] (Arrangement of processes)

[0291] In the arrangement process 102, the 80 steel cords 12 pulled out from the drum 11 in the pulling process 101 are arranged in a row in a cross section perpendicular to the length direction of the steel cords 12.

[0292] Specifically, in the arrangement process 102, using Figure 6A , Figure 6BThe composite roller 141 shown pulls 80 steel cords 12, i.e., steel cord group 2, along a specified direction. Then, it is fed into... Figure 6C The slits 1421 pre-etched on the guide plate 142 are used for arrangement. In addition, the position of the steel cord 12 is further corrected and arranged by the grooved roller 15 disposed on the downstream side of the conveying direction of the steel cord 12.

[0293] The slot 1421 engraved on the guide plate 142 used in the arrangement process 102, and the size of the groove formed on the grooved roller 15 are selected in such a way that they are large enough compared to the size of the steel cord 12, and the steel cord 12 generally does not contact the surface of the slot 1421 or the groove.

[0294] (Rubber composite manufacturing process)

[0295] In the rubber composite manufacturing process 103, 80 steel cords, namely steel cord group 2, are embedded in the rubber to manufacture the rubber composite.

[0296] Specifically, using calendering rolls 17, 80 steel cords 12, i.e. steel cord groups 2, are arranged between rubber 16 for calendering to produce rubber composite 40.

[0297] The rubber 16 mentioned above uses the same rubber as in Experimental Example 1-1.

[0298] In this experimental example, the steel cords are arranged at a density of 60 cords / 5cm. The thickness T of the rubber composite is a value obtained by adding the distribution width W of the two or more steel cords arranged in the thickness direction within the rubber composite to the rubber thickness predetermined in a manner that allows the steel cords to be embedded.

[0299] The evaluation results are shown in Table 2.

[0300] [Experimental Example 2-2, Experimental Example 2-3]

[0301] The tension adjustment device was set so that the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord was as shown in Table 2. Apart from the above, a rubber composite was manufactured in the same manner as in Experimental Example 2-1, and its performance was evaluated. The evaluation results are shown in Table 2.

[0302] [Experimental Example 2-4]

[0303] Each drum has a steel cord wound around it as the drum used for the drum setting process. It should be noted that the winding pitch of the steel cord on each drum is 1.2 mm.

[0304] In Experiment 2-4, according to Figure 2The steps of the method for manufacturing the rubber composite shown are as follows: The rubber composite is manufactured. Then, 80 of the above-mentioned rolls, i.e., roll assemblies, are arranged in the steel cord supply device in such a way that the same number of steel cords as in other experimental examples can be supplied.

[0305] It should be noted that in order to set up 80 rolls, such as Figure 2 The steel cord supply device 20 shown is modified in advance to increase the number of ports.

[0306] Except for the aspects mentioned above, the rubber composite was manufactured in the same manner as in Experimental Example 2-1. The resulting rubber composite was then evaluated. The evaluation results are shown in Table 2.

[0307] [Experimental Example 2-5]

[0308] The tension adjustment device was set so that the ratio of the tension of each steel cord to the breaking load of each steel cord was as shown in Table 2. Except for this aspect, the rubber composite was manufactured in the same manner as in Experimental Example 2-1, and the results were evaluated. The evaluation results are shown in Table 2.

[0309] [Table 2]

[0310]

[0311] In Experimental Examples 2-1 to 2-3, 80 steel cords were supplied to the manufacturing process. However, it was confirmed that, compared to, for example, Experimental Example 2-4, the number of rolls used to supply the steel cords could be suppressed.

[0312] In Experimental Examples 2-1 to 2-3, as shown in Table 2, the ratio of the tension of each steel cord supplied to the arrangement process to the breaking load of each steel cord is 6.0% or more and 9.0% or less.

[0313] Furthermore, it can be confirmed that, compared to the rubber composite of Experimental Example 2-5 which does not meet the above requirements, the rubber composites obtained in Experimental Examples 2-1 to 2-3 above can suppress the deviation of the position of the steel cord in the thickness direction of the rubber composite. The results also confirm that, compared to the rubber composite obtained in Experimental Example 2-5, the rubber composites obtained in Experimental Examples 2-1 to 2-3 can also suppress the weight index.

[0314] Furthermore, in Experiment 2-4, the number of rollers used was greater than in Experiments 2-1 to 2-3. Therefore, it can be confirmed that the degree of freedom in setting up the rollers decreased, and the distribution of the feed angle increased. The results confirm that the coating of the steel cord in the obtained rubber composite exhibits defects.

[0315] Symbol Explanation

[0316] 100 Roller Setting Process

[0317] 101 Pull-out process

[0318] 102 Arrangement Process

[0319] 103 Rubber Composite Manufacturing Process

[0320] 104 Tension Adjustment Process

[0321] 1041 First tension adjustment process

[0322] 1042 Second tension adjustment process

[0323] 10, 20 steel cord supply device

[0324] 1A and 1B drum sets

[0325] 11, 21 rolls

[0326] A Dashed line

[0327] θ (incoming line angle)

[0328] 111 Flange

[0329] 111A First inner surface

[0330] 111B Second inner surface

[0331] 112 axis

[0332] 2 steel cord sets

[0333] 12, 12A~12J steel cord

[0334] 121 First steel cord

[0335] 122 Second steel cord

[0336] Distance between L111 and L112

[0337] 123 Measurement Area

[0338] CA central axis

[0339] P winding pitch

[0340] 13 guide rollers

[0341] 131 First tension adjusting device

[0342] 1311 Rotating Axis

[0343] 1312 Tension Adjustment Arm

[0344] 1313 First tension adjusting roller

[0345] B Double-headed arrow

[0346] 132 Second tension adjustment device

[0347] C Double-headed arrow

[0348] 14 Arrangement device

[0349] 141 Composite Roller

[0350] 1411 First Roller

[0351] 1412 Second Roller

[0352] 142 guide plate

[0353] 1421 Slit

[0354] 15 Grooved Rollers

[0355] 16 Rubber

[0356] 17 Calendering Rolls

[0357] 31 steel wire

[0358] 32 Coating

[0359] D Cord Diameter

[0360] 40 Rubber Composite

[0361] 40A First Page

[0362] 40B Second Page

[0363] 40C First end

[0364] 41 Rubber

[0365] 401 Flat surface

[0366] 402 baseline

[0367] O 12A center

[0368] L 12B ~L 12I Maximum length

[0369] W 12B Deviation range

[0370] R radius

[0371] T thickness

[0372] W distribution width

[0373] XX axis (width direction)

[0374] YY axis (length direction)

[0375] ZZ axis (thickness direction)

[0376] 50 tires

[0377] 51 Fetal face

[0378] 52 Sidewall

[0379] 53. Bead section

[0380] 54 Inner Liner

[0381] 55. Tire carcass (rubber composite)

[0382] 56. Belt layer (rubber composite)

[0383] 57 Bead wire

[0384] CL centerline

Claims

1. A method for manufacturing a rubber composite, It has the following characteristics: The drum setting process involves setting the drum assembly in the steel cord supply device, wherein the drum assembly consists of two or more drums each wound with two or three steel cords. In the pulling-out process, the steel cord supply device is used to pull out two or three steel cords respectively wound on the drum from the drum assembly; The arrangement process involves arranging two or more steel cords, i.e., steel cord groups, pulled from the drum assembly in a row, with the steel cords forming the steel cord groups in a cross-section perpendicular to the length direction of the steel cords; and The rubber composite manufacturing process involves embedding the steel cord assembly within rubber to create the rubber composite. The steel cord is a single-strand steel cord. A tension of 6.0% to 9.0% of the breaking load of each steel cord constituting the steel cord assembly is applied to each steel cord supplied to the arrangement process. Between the pulling-out process and the arranging process, there is a tension adjustment process for adjusting the tension of the steel cord. In the tension adjustment process, the tension of the steel cord is adjusted by changing the position of the tension adjustment roller that contacts the conveyed steel cord. The angle between the steel cord supplied before the arrangement process and the steel cord after the arrangement process, i.e. the inlet angle, is 40 degrees or more and 50 degrees or less.

2. The method for manufacturing the rubber composite as described in claim 1, wherein, Two steel cords are wound on the drum.

3. The method for manufacturing the rubber composite as described in claim 1, wherein, The tension adjustment process includes at least a first tension adjustment process and a second tension adjustment process.

4. A tire manufacturing method comprising a tire manufacturing step of manufacturing a tire using a rubber composite obtained by the manufacturing method of a rubber composite according to any one of claims 1 to 3.

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