tire
By positioning electronic components at the intersection of multiple rubber members and covering them with a coated rubber sheet, the stress-related issues in tires with embedded electronics are addressed, ensuring the components' functionality and improved communication performance.
Patent Information
- Application Number
- JP2023206605
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2023-12-07
- Publication Date
- 2025-04-23
- Estimated Expiration
- 2039-06-19
Smart Images

Figure 0007667844000001 
Figure 0007667844000002 
Figure 0007667844000003
Abstract
Description
[Technical field]
[0001] The present invention relates to a tire having an embedded electronic component. [Background technology]
[0002] Conventionally, tires have been known in which electronic components such as RFID tags are embedded in the rubber structure. Such tires can perform manufacturing management, usage history management, and the like, by communicating between an RFID tag embedded in the tire and a reader as an external device. For example, Patent Document 1 discloses a tire in which a patch combined with an electrical component having an antenna is disposed in a portion adjacent to the inner liner. It also shows that the electrical component can be disposed between the carcass and the sidewall or between the carcass and the tread portion. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] JP 2005-335384 A Summary of the Invention [Problem to be solved by the invention]
[0004] In the technology disclosed in Patent Document 1, for example, when an electrical component is disposed between the carcass and the sidewall, the carcass and the sidewall have significantly different physical properties, and therefore, due to the difference in physical properties, such as the linear expansion coefficient and elastic modulus, relative movement occurs between the two components during vulcanization or use, and the electrical component may be subjected to stress. If the allowable stress is exceeded, the electrical component may not be able to maintain its function. Furthermore, if electrical components are simply sandwiched between two rubber members, it is difficult to set a standard for the placement of the electrical components, and the placement of the electrical components may vary. As a result, the electrical components may be placed in undesirable positions in terms of stress, distortion, etc., and may not be able to maintain their functionality.
[0005] The present invention has been made in view of the above problems, and an object of the present invention is to provide a tire in which embedded electronic components can maintain their functionality. [Means for solving the problem]
[0006] (1) A tire of the present invention (e.g., tire 1) includes a plurality of rubber members constituting the tire and an electronic component (e.g., RFID tag 40), and the electronic component is disposed at an intersection of at least three rubber members.
[0007] (2) In the tire of (1), each of the three rubber members may be annular rubber members formed in an annular shape.
[0008] (3) In the tire of (2), a shoulder pad (e.g., shoulder pad 38) is provided as a rubber member that is arranged on the outer surface side of the carcass ply (e.g., carcass ply 23) and is arranged on the inner cavity side of the tread rubber (e.g., tread rubber 28) and the sidewall rubber (e.g., sidewall rubber 30), and the electronic component may be arranged at a position where the shoulder pad, the tread rubber, and the sidewall rubber intersect.
[0009] (4) In the tires of (1) to (3), at least a portion of the electronic component may be covered with a covering rubber sheet (e.g., covering rubber sheets 431, 432), and the covering rubber sheet covering the electronic component may be disposed at a position where at least three rubber members intersect.
[0010] (5) In the tire of (4), the three rubber members include a first rubber member, a second rubber member arranged to cover a portion of the first rubber member and having a tapered end in a cross-sectional view in the tire width direction, and a third rubber member covering at least a boundary portion between the first rubber member and the second rubber member, and the covering rubber sheet may be arranged to straddle the first rubber member and the second rubber member at the boundary portion between the first rubber member and the second rubber member, and be covered by the third rubber member.
[0011] (6) A manufacturing method for manufacturing a tire of (5) may include a step of attaching the covering rubber sheet at a boundary between the first rubber member and the second rubber member so as to straddle the first rubber member and the second rubber member, and a step of attaching the third rubber member so as to cover the covering rubber sheet attached to the boundary between the first rubber member and the second rubber member. Effect of the Invention
[0012] According to the present invention, it is possible to provide a tire in which embedded electronic components can maintain their functionality. [Brief description of the drawings]
[0013] [Figure 1] 1 is a view showing a half cross section in the tire width direction of a tire according to a first embodiment of the present invention. [Diagram 2] 1 is a partially enlarged cross-sectional view of a tire according to a first embodiment of the present invention. [Figure 3A] FIG. 2 is a diagram showing an RFID tag protected by a protective member in a tire according to a first embodiment of the present invention. [Figure 3B] FIG. 3B is a diagram showing a cross section bb of FIG. 3A. [Figure 3C] FIG. 3B is a diagram showing a cross section cc of FIG. 3A. [Figure 4A] FIG. 2 is a diagram showing the peripheral portion of the protective member during the manufacturing process of the tire according to the first embodiment of the present invention, as viewed from the outer side in the tire width direction. [Figure 4B]FIG. 10 is a diagram showing a peripheral portion of a protective member in a modified example of a manufacturing process for a tire according to the first embodiment of the present invention, as viewed from the outer side in the tire width direction. [Figure 4C] FIG. 4 is a diagram showing an annular rubber sheet as a modified example of the protective member in the tire according to the first embodiment of the present invention. [Diagram 5] FIG. 2 is a partially enlarged cross-sectional view of a tire according to a first modified example of the first embodiment of the present invention. [Figure 6] FIG. 4 is a partially enlarged cross-sectional view of a tire according to a second modified example of the first embodiment of the present invention. [Figure 7] FIG. 4 is a partially enlarged cross-sectional view of a tire according to a second embodiment of the present invention. [Figure 8] FIG. 13 is a diagram showing the results of a simulation of the in-plane distribution of strain energy when a tire is mounted on a rim and a 100% load is applied. [Figure 9] FIG. 5 is a partially enlarged cross-sectional view of a tire according to a third embodiment of the present invention. [Figure 10] FIG. 11 is a partially enlarged cross-sectional view of a tire according to a first modified example of the third embodiment of the present invention. [Figure 11] FIG. 13 is a partially enlarged cross-sectional view of a tire according to a second modified example of the third embodiment of the present invention. [Figure 12] 12 is a diagram of a bead filler, a rubber sheet, and a protective member during the tire manufacturing process of FIG. 11, as viewed from the outer side in the tire width direction. [Figure 13] FIG. 13 is a partially enlarged cross-sectional view of a tire according to a third modified example of the third embodiment of the present invention. [Figure 14] FIG. 13 is a cross-sectional view of the spring antenna before the RFID tag is sandwiched between rubber sheets when no rubber is filled inside the spring antenna. [Figure 15] FIG. 13 is a cross-sectional view of the spring antenna after the RFID tag is sandwiched between rubber sheets when no rubber is filled inside the spring antenna. [Figure 16] FIG. 13 is a cross-sectional view of the spring antenna after the RFID tag is sandwiched between rubber sheets when no rubber is filled inside the spring antenna. [Figure 17]FIG. 13 is a diagram showing an RFID tag before rubber is filled inside a spring antenna in a tire according to a fourth embodiment of the present invention. [Figure 18] FIG. 13 is a diagram showing an RFID tag after the spring antenna has been filled with rubber in a tire according to a fourth embodiment of the present invention. [Figure 19] FIG. 13 is a diagram showing an RFID tag before being sandwiched between rubber sheets in a tire according to a fourth embodiment of the present invention. [Figure 20] FIG. 13 is a diagram showing an RFID tag sandwiched between rubber sheets in a tire according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a diagram showing a half cross section in the tire width direction of a tire 1 according to this embodiment. The basic structure of the tire is symmetrical in the cross section in the tire width direction, so a cross section of the right half is shown here. In the figure, the symbol S1 indicates the tire equatorial plane. The tire equatorial plane S1 is a plane that is perpendicular to the tire rotation axis and is located at the center in the tire width direction. Here, the tire width direction is a direction parallel to the tire rotation axis, and corresponds to the left-right direction on the paper in the cross-sectional view of Fig. 1. In Fig. 1, this direction is illustrated as tire width direction X. The inner side in the tire width direction is the direction approaching the tire equatorial plane S1, and is the left side on the paper in Fig. 1. The outer side in the tire width direction is the direction away from the tire equatorial plane S1, and is the right side on the paper in Fig. 1. The tire radial direction is a direction perpendicular to the tire rotation axis, and is the up-down direction on the paper surface in Fig. 1. In Fig. 1, this direction is illustrated as tire radial direction Y. The outer side in the tire radial direction is the direction away from the tire rotation axis, and is the upper side on the paper in Fig. 1. The inner side in the tire radial direction is the direction approaching the tire rotation axis, and is the lower side on the paper in Fig. 1. The same applies to Figures 2, 5-7, 9-11, and 13.
[0015] The tire 1 is, for example, a tire for trucks or buses, and has a pair of beads 11 provided on both sides in the tire width direction, a tread 12 that forms a contact surface with the road surface, and a pair of sidewalls 13 extending between the pair of beads 11 and the tread 12.
[0016] The bead 11 includes an annular bead core 21 formed by winding a metal bead wire covered with rubber several times, and a tapered bead filler 22 extending outward in the tire radial direction of the bead core 21. The bead filler 22 is composed of a first bead filler 221 covering the outer periphery of the bead core 21, and a second bead filler 222 arranged on the outer side of the first bead filler 221 in the tire radial direction. The second bead filler 222 is composed of rubber having a higher modulus than the inner liner 29 and the sidewall rubber 30 described later. The first bead filler 221 is composed of rubber having an even higher modulus than the second bead filler 222. Note that the first bead filler 221 may not cover the outer periphery of the bead core 21 as long as at least a part of it is arranged on the outer side of the bead core 21 in the tire radial direction. The bead filler 22 may be formed of one type of rubber. In other words, the first bead filler 221 and the second bead filler 222 do not have to be separated. The bead core 21 is a member that serves to fix an air-filled tire to the rim of a wheel (not shown). The bead filler 22 is a member that is provided to increase the rigidity of the periphery of the bead and ensure high maneuverability and stability.
[0017] A carcass ply 23 constituting a ply that forms the framework of the tire is embedded inside the tire 1. The carcass ply 23 extends from one bead core to the other bead core. That is, the carcass ply 23 is embedded in the tire 1 in a manner that passes between a pair of bead cores 21, a pair of sidewalls 13, and the tread 12. 1, the carcass ply 23 includes a ply body 24 extending from one bead core to the other bead core and extending between the tread 12 and the bead 11, and a ply turn-up portion 25 turned up around the bead core 21. Here, a turn-up end 25A of the ply turn-up portion 25 is located radially inward of an outer end 22A of the bead filler 22 in the tire radial direction. The carcass ply 23 is composed of a plurality of ply cords extending in the tire width direction. The plurality of ply cords are also arranged side by side in the tire circumferential direction. The ply cord is made of a metal steel cord or an insulating organic fiber cord made of polyester, polyamide, or the like, and is covered with rubber.
[0018] In the tread 12, multiple layers of steel belts 26 are provided on the tire radially outer side of the carcass ply 23. The steel belts 26 are composed of multiple steel cords covered with rubber. By providing the steel belts 26, the rigidity of the tire is ensured and the contact state between the tread 12 and the road surface is improved. In this embodiment, four layers of steel belts 26 are provided, but the number of stacked steel belts 26 is not limited to this.
[0019] A tread rubber 28 is provided on the radially outer side of the steel belt 26. A tread pattern (not shown) is provided on the outer surface of the tread rubber 28, and this outer surface becomes the contact surface that comes into contact with the road surface.
[0020] A shoulder pad 38 serving as a pad is provided in the vicinity of the outer side in the tire width direction of the tread 12, i.e., in the end region in the tire width direction of the steel belt 26 and the tread rubber 28, in the region between the carcass ply 23, and the steel belt 26 and the tread rubber 28. This shoulder pad 38 extends to the outer region in the tire radial direction of the sidewall 13, and a part of it forms an interface with a sidewall rubber 30 described below. That is, in the outer region in the tire radial direction of the sidewall 13, a part of the shoulder pad 38 is present on the inner side in the tire width direction of the sidewall rubber 30. In other words, in the extending portion of the shoulder pad 38, from the inner cavity side of the tire toward the outer surface side of the tire, the extending portion of the shoulder pad 38 and the sidewall rubber 30 are laminated in this order on the carcass ply 23. That is, in a part of the carcass ply 23, the shoulder pad 38 and the sidewall rubber 30 are laminated. The shoulder pad 38 is made of a rubber member having cushioning properties, and exhibits a cushioning function between the carcass ply 23 and the steel belt 26. In addition, since the shoulder pad 38 is made of rubber having low heat generation properties, by extending it to the sidewall 13, heat generation can be effectively suppressed. In this manner, the shoulder pad 38 is disposed on the tire outer surface side of the carcass ply 23 and on the tire inner cavity side of the tread rubber 28 and the sidewall rubber 30 .
[0021] An inner liner 29 serving as a rubber layer constituting the inner wall surface of the tire 1 is provided on the tire cavity side of the carcass ply 23 in the beads 11, sidewalls 13, and tread 12. The inner liner 29 is made of air-permeable resistant rubber and prevents air in the tire cavity from leaking to the outside.
[0022] In the sidewall 13, a sidewall rubber 30 that constitutes the outer wall surface of the tire 1 is provided on the outer side of the carcass ply 23 in the tire width direction. This sidewall rubber 30 is the part that bends the most when the tire performs its cushioning function, and flexible rubber having fatigue resistance is usually used for this sidewall rubber.
[0023] A steel chafer 31 is provided as a reinforcing ply on the tire radially inner side of the carcass ply 23 provided around the bead core 21 of the bead 11 so as to cover at least a part of the carcass ply 23. The steel chafer 31 also extends on the tire width direction outer side of the ply turn-up portion 25 of the carcass ply 23, and an end 31A of the steel chafer 31 is located on the tire radially inner side of the turn-up end 25A of the carcass ply 23. The steel chafer 31 is a metal reinforcing layer made of metal steel cords and is covered with rubber.
[0024] A rim strip rubber 32 is provided on the inner side in the tire radial direction of the steel chafer 31. This rim strip rubber 32 is arranged along the outer surface of the tire and is connected to the sidewall rubber 30. This rim strip rubber 32 and the sidewall rubber 30 are rubber members that make up the outer surface of the tire.
[0025] A first pad 35 is provided on the tire radial outer side of the end portion 31A of the steel chafer 31 and on the tire width direction outer side of the turned-up portion 25 of the carcass ply 23 and the bead filler 22. This first pad 35 is provided on at least the tire width direction outer side of the turned-up end 25A of the carcass ply 23. The tire radial outer side of the first pad 35 is formed to taper toward the tire radial outer side.
[0026] Furthermore, a second pad 36 is provided so as to cover the outer side in the tire width direction of the first pad 35. More specifically, the second pad 36 is provided so as to cover the outer side in the tire width direction of a part of the steel chafer 31, the first pad 35, a part of the second bead filler 222, and a part of the ply body 24 of the carcass ply 23. A sidewall rubber 30 is arranged on the outer side in the tire width direction of the tire radial outer region of the second pad 36, and a rim strip rubber 32 is arranged on the outer side in the tire width direction of the tire radial inner region of the second pad 36. In other words, the second pad 36 is provided between the first pad 35 etc. and the rim strip rubber 32 and the sidewall rubber 30 which are members constituting the outer surface of the tire.
[0027] The first pad 35 and the second pad 36 constitute a pad member 34, and this pad member 34 is made of rubber having a higher modulus than the modulus of the outer portion (second bead filler 222) of the bead filler 22 in the tire radial direction. More specifically, the second pad 36 is made of rubber having a higher modulus than the second bead filler 222, and the first pad 35 is made of rubber having an even higher modulus than the second pad 36. The first pad 35 and the second pad 36 have the function of mitigating sudden distortion caused by localized changes in rigidity at the turned-up end 25A of the carcass ply 23 and the end 31A of the steel chafer 31.
[0028] A rubber sheet 37 serving as a reinforcing rubber sheet is disposed between the bead filler 22 and the pad member 34 near the turned-up end 25A of the carcass ply 23. The rubber sheet 37 is disposed so as to cover the turned-up end 25A of the carcass ply 23 from the inner side in the tire width direction. The rubber sheet 37 is made of rubber having a higher modulus than the second bead filler 222. More preferably, the rubber sheet 37 is made of rubber having a modulus approximately equal to that of the first pad .
[0029] Generally, stress is likely to concentrate at the folded end 25A of the carcass ply 23. However, by providing the rubber sheet 37 as the reinforcing rubber sheet described above, it becomes possible to effectively suppress the concentration of stress. In this embodiment, the pad member 34 is composed of the first pad 35 and the second pad 36, but the pad member 34 may be composed of a single member. However, as described above, by adopting a configuration in which the pad member 34 is composed of the first pad 35 and the second pad 36 and further includes the rubber sheet 37, it is possible to more effectively suppress the concentration of stress.
[0030] In this embodiment, the position of the tire radial direction outer end 37A of the rubber sheet 37 is located radially inward of the tire radial direction outer end 22A of the bead filler 22. However, the position of the tire radial direction outer end 37A of the rubber sheet 37 may be substantially aligned with the position of the tire radial direction outer end 22A of the bead filler 22. 1, it is preferable to adopt a mode in which the rubber sheet 37 is disposed so as to cover the folded end 25A of the carcass ply 23 from the inner side in the tire width direction, but a configuration in which the folded end 25A of the carcass ply 23 is covered from the outer side in the tire width direction may be adopted. Even in this case, it is possible to reduce the concentration of stress.
[0031] In the tire 1 of this embodiment, an RFID tag 40 is embedded as an electronic component. The RFID tag 40 is a passive transponder equipped with an RFID chip and an antenna for communicating with an external device, and performs wireless communication with a reader (not shown) as the external device. As the antenna, various types of antennas such as a coil-shaped spring antenna, a plate-shaped antenna, and a rod-shaped antenna may be used. For example, the antenna may be formed by printing a predetermined pattern on a flexible substrate. The antenna is set to an optimized antenna length according to the frequency band to be used, etc. Identification information such as a serial number and a part number is stored in a memory unit in the RFID chip.
[0032] FIG. 2 is an enlarged cross-sectional view showing the periphery of the embedded portion of the RFID tag 40 in the tire 1 of FIG. The RFID tag 40 (including a state where at least a part of it is covered by a protective member 43 described later) is disposed at a position where at least three rubber members constituting the tire 1 intersect. More specifically, the tire 1 of this embodiment includes a shoulder pad 38 as a first rubber member in this embodiment, a tread rubber 28 as a second rubber member in this embodiment that is disposed so as to cover a part of the shoulder pad 38, and a sidewall rubber 30 as a third rubber member in this embodiment that covers at least the boundary between the shoulder pad 38 and the tread rubber 28, and the RFID tag 40 is disposed at a position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect.
[0033] More preferably, the RFID tag 40 is integrally covered with a protective member 43 made of a covering rubber sheet described later, and this protective member 43 is arranged to straddle the shoulder pad 38 and the tread rubber 28 at the boundary between the shoulder pad 38 and the tread rubber 28. That is, this protective member 43 is attached so as to press the tire radial direction inner end 28B of the tread rubber 28, which has a tapered shape at the tire radial direction inner end in a cross section in the tire width direction, from the tire outer surface side. The tire outer surface side of this protective member 43 is covered by the sidewall rubber 30.
[0034] Here, the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 are each annular rubber members that constitute the annular tire 1. A protection member 43 that holds an RFID tag 40 is disposed so as to be in surface contact with the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30.
[0035] If the RFID tag 40 is placed in such a position, the RFID tag 40 is surrounded by multiple rubber members, specifically, the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30, so that the RFID tag 40 is less susceptible to the effects of stress. Furthermore, by using the boundary between multiple rubber members, in this embodiment, the boundary between the shoulder pad 38 and the tread rubber 28, as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately.
[0036] Furthermore, by arranging the RFID tag 40 in the shoulder portion, i.e., near the outer side in the tire radial direction of the sidewall, the RFID tag 40 can be arranged at a position sufficiently away from the metallic bead core 21, which may adversely affect communication. Here, the bead core 21 is formed into an annular shape by laminating and winding metallic bead wires, and is therefore a metallic member that is particularly likely to adversely affect communication. Also, in consideration of communication quality, it is preferable to place the RFID tag 40 as close as possible to the outer surface of the tire 1. If the RFID tag 40 is placed on the inner cavity side of the carcass ply 23, the communication quality will decrease because it will be far from the outer surface of the tire 1. Furthermore, if the carcass ply 23 is made of metal, placing the RFID tag 40 on the inner cavity side of the carcass ply 23 will significantly decrease the communication quality. Considering these points, the position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect is a suitable position for embedding the RFID tag 40.
[0037] In addition, in consideration of embedding the RFID tag 40 during the tire manufacturing process, it is preferable to place the RFID tag 40 at the intersection of three rubber members constituting the tire. For example, when the RFID tag 40 is sandwiched between layers of wound ribbon-shaped rubber members, the timing of attaching the RFID tag 40 to the ribbon-shaped rubber member becomes complicated. In addition, when the RFID tag 40 is simply placed between two rubber members, it is difficult to set a reference for the placement position, and the placement position of the electric parts may vary. On the other hand, if the RFID tag 40 is placed at the intersection of three rubber members as in this embodiment, the RFID tag 40 can be attached to the boundary between the first rubber member (in this embodiment, the shoulder pad 38) and the second rubber member (in this embodiment, the tread rubber 28) with high accuracy in the tire molding process, and then the third rubber member (in this embodiment, the sidewall rubber 30) can be overlapped thereon to sandwich the RFID tag 40. Considering these points, the position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect is a suitable position for embedding the RFID tag 40.
[0038] Furthermore, even when the RFID tag 40 is sandwiched between plies such as the carcass ply 23, for example, when the sandwiched plies move in different directions, the RFID tag 40 may be subjected to stress. Also, even when the RFID tag 40 is sandwiched between a ply such as the carcass ply 23 and a rubber member such as a sidewall rubber, the ply and the rubber member have significantly different physical properties, and therefore, due to the differences in physical properties, such as linear expansion coefficient, elastic modulus, hardness, etc., relative movement may occur between the two members during vulcanization or use, and the RFID tag 40 may be subjected to stress. If the allowable stress is exceeded, the RFID tag 40 may not be able to maintain its function. The shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 are all rubber members, and taking these points into consideration, the position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect is an ideal position for embedding the RFID tag 40.
[0039] The shoulder pad 38 has cushioning properties, so that if the RFID tag 40 is placed on this portion, distortion occurring around the RFID tag 40 can be absorbed. In addition, the shoulder pad has low heat generation properties, so the RFID tag 40 provided in such a position is less susceptible to heat generated by the rubber during use. Considering these points, the position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect is a suitable position for embedding the RFID tag 40.
[0040] Furthermore, if the RFID tag 40 is disposed at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30, the RFID tag 40 will not be removed even in the case of retreading. In other words, since the portion of the tread rubber 28 that is removed during retreading is at least the outer side of the steel belt 26 in the tire radial direction, if the RFID tag 40 is disposed at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30, the RFID tag 40 will not be removed and can continue to be used. In this respect, too, the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 is a suitable position for embedding the RFID tag 40.
[0041] In addition, taking the modulus of the shoulder pad 38 as a reference, the sidewall rubber 30 preferably has a modulus that is 0.4 to 0.7 times that of the shoulder pad 38. In addition, the tread rubber 28 preferably has a modulus that is 0.4 to 0.9 times that of the shoulder pad 38. By setting the modulus in this range, it is possible to maintain a balance between flexibility and rigidity as a tire. The modulus refers to the 100% elongation modulus (M100) measured in an atmosphere of 23° C. in accordance with “3.7 Stress at a given elongation, S” of JIS K6251:2010.
[0042] Here, the RFID tag 40 is covered with covering rubber sheets 431 and 432 that constitute a protective member 43 . This will be described with reference to FIGS. 3A to 3C.
[0043] Fig. 3A is a diagram showing an RFID tag 40 covered with a protective member 43 formed of a rubber sheet. In Fig. 3A, the RFID tag 40 is covered and hidden by a covering rubber sheet 431 described later. Fig. 3B is a cross-sectional view taken along line bb in Fig. 3A, and Fig. 3C is a cross-sectional view taken along line cc in Fig. 3A.
[0044] The RFID tag 40 includes an RFID chip 41 and an antenna 42 for communicating with an external device. As the antenna 42, various types of antennas such as a coil spring antenna, a plate antenna, and a rod antenna may be used. For example, the antenna may be an antenna formed by printing a predetermined pattern on a flexible substrate. In consideration of communication properties and flexibility, a coil spring antenna is most preferable. The antenna is set to an optimized antenna length according to the frequency band to be used, etc.
[0045] The protective member 43 is composed of two covering rubber sheets 431 and 432 that sandwich the RFID tag 40 to protect it.
[0046] The protective member 43 is made of, for example, rubber having a predetermined modulus. Here, the modulus refers to the 100% elongation modulus (M100) measured in an atmosphere of 23° C. in accordance with “3.7 Stress at a given elongation, S” of JIS K6251:2010.
[0047] The rubber used for the protective member 43 has a modulus at least higher than that of the sidewall rubber 30. For example, rubber having a modulus higher than that of the sidewall rubber 30 and lower than that of the shoulder pad 38 is used.
[0048] For example, it is more preferable to use rubber having a modulus 1.1 to 1.8 times that of the sidewall rubber 30 as the standard for the rubber used in the protective member 43. In this case, the rubber used in the shoulder pad 38 may have a modulus 1.6 to 3 times that of the sidewall rubber, for example, about twice as much. If emphasis is placed on strengthening the protection of the RFID tag 40, the rubber used for the protection member 43 may have a higher modulus than the shoulder pad .
[0049] 1 and 2, the RFID tag 40 is disposed in the region where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect. Therefore, by setting the modulus of the protective member 43 to a value higher than that of the sidewall rubber 30 and lower than that of the shoulder pad 38, it is possible to prevent excessive stress from being generated in the rubber structure at the portion where the RFID tag 40 is embedded when the tire is deformed. In other words, it is possible to suppress the generation of stress.
[0050] The protective member 43 may be made of rubber mixed with short fiber filler. As the short fiber filler, for example, insulating short fibers such as organic short fibers such as aramid short fibers and cellulose short fibers, ceramic short fibers such as alumina short fibers, and inorganic short fibers such as glass short fibers can be used. By mixing such short fiber filler into rubber, the strength of the rubber can be increased. Also, a rubber sheet in a vulcanized state may be used as the protective member 43. A rubber sheet in a vulcanized state does not undergo plastic deformation like raw rubber, and therefore can adequately protect the RFID tag 40. However, in consideration of the ease of attachment during the manufacturing process and the stabilization of the rubber structure by integration with other rubber members during vulcanization, it is more preferable to use a rubber sheet of a predetermined thickness in a pre-vulcanized state as the protective member 43.
[0051] Moreover, an organic fiber layer made of polyester fiber, polyamide fiber, or the like may be provided as the protective member 43. It is also possible to embed an organic fiber layer between the two covering rubber sheets 431 and 432.
[0052] Next, a manufacturing process of the tire 1 will be described. FIG. 4A is a diagram of the peripheral portion of protective member 43 during the manufacturing process as viewed from the outside in the tire width direction, and shows protective member 43 covering RFID tag 40 attached to boundary portion B between shoulder pad 38 and tread rubber 28.
[0053] The RFID tag 40 covered with the protective member 43 is attached before the vulcanization step in the tire manufacturing process. 4A, in the manufacturing process of the tire 1 in this embodiment, the protective member 43 covering the RFID tag 40 is attached to the boundary portion B between the shoulder pad 38 and the tread rubber 28 so as to straddle the shoulder pad 38 and the tread rubber 28. That is, the protective member 43 is attached so as to press the tire radial direction inner end 28B of the tread rubber 28, which has a tapered shape at the tire radial direction inner end in a tire width direction cross section (FIGS. 1 and 2). By attaching the protective member 43 to such a position, it is possible to partially assist the joining between the rubber members, specifically, the joining between the shoulder pad 38 and the tread rubber 28.
[0054] Furthermore, by using the boundary between multiple rubber members, in this embodiment, the boundary B between the shoulder pad 38 and the tread rubber 28 as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, etc., and allows the RFID tag 40 to maintain its proper function.
[0055] 4A (see FIGS. 1 and 2), is attached so as to cover the protective member 43 attached to the boundary portion B between the shoulder pad 38 and the tread rubber 28. As a result, the RFID tag 40 covered with the protective member 43 is disposed at the intersection of at least three rubber members constituting the tire 1, in this embodiment, at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30.
[0056] At this time, since the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 are in the state of raw rubber before vulcanization, the protective member 43 covered with the protective member 43 may be attached to these components by utilizing their adhesiveness. Alternatively, when the adhesiveness is low, the protective member 43 may be attached using an adhesive or the like.
[0057] In this manner, the rubber components constituting the tire are assembled to form a green tire. Thereafter, the raw tire to which each component part including the RFID tag 40 is assembled is vulcanized in a vulcanization process to manufacture a tire.
[0058] In this manner, in this embodiment, the RFID tag 40 covered with the protective member 43 can be affixed to the shoulder pad 38 and the tread rubber 28 in a raw rubber state during tire manufacturing, which facilitates the installation of the RFID tag 40 in the tire manufacturing process. In particular, the shoulder pad 38 has a certain degree of rigidity even in a raw rubber state, which facilitates the installation of the RFID tag 40 covered with the protective member 43.
[0059] As a modified example of the manufacturing process of the tire 1, the following manufacturing process may be adopted. That is, the protective member 43 covered by the RFID tag 40 is attached to the sidewall rubber 30, and then the sidewall rubber 30 to which the protective member 43 is attached is attached to the shoulder pad 38 and the tread rubber 28. Here, the protective member 43 is attached to the sidewall rubber 30 so that the protective member 43 is positioned at the boundary portion B between the shoulder pad 38 and the tread rubber 28 when the sidewall rubber 30 is attached to the shoulder pad 38 and the tread rubber 28. Even when such a process is adopted, the RFID tag 40 covered with the protective member 43 is placed at the intersection of at least three rubber members constituting the tire 1, i.e., the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30. Since the RFID tag 40 is surrounded by multiple rubber members, the RFID tag 40 is less susceptible to the effects of stress. The boundaries between the multiple rubber members serve as a reference for the placement position of the RFID tag 40.
[0060] Furthermore, if the protective member 43 is formed of two covering rubber sheets 431, 432, the RFID tag 40 including the protective member 43 can be formed thin, which is suitable for embedding in the tire 1. Furthermore, when assembling the RFID tag 40 to a component of the tire 1 before vulcanization, the RFID tag 40 covered by the covering rubber sheets can be attached very easily. For example, the RFID tag 40 covered by the covering rubber sheets 431, 432 can be appropriately attached to a desired position of a member, such as a boundary between multiple rubber members before vulcanization, by utilizing the adhesiveness of raw rubber. Also, by using the covering rubber sheets 431, 432 as raw rubber before vulcanization, the adhesiveness of the covering rubber sheets themselves can be utilized to more easily attach the RFID tag 40.
[0061] However, the protective member 43 is not limited to being constituted by two covering rubber sheets, and various other configurations can be adopted. For example, as long as the covering rubber sheet constituting the protective member covers at least a part of the RFID tag 40, it is possible to obtain effects such as improved workability and stress relief in the manufacturing process. Therefore, a configuration in which only one side of the RFID tag 40 is covered by one covering rubber sheet 431 as the protective member may be adopted. Also, for example, a configuration in which one rubber sheet is wrapped around the entire circumference of the RFID tag 40, or a configuration in which a protective member in the form of a highly viscous potting agent is attached to the entire circumference of the RFID tag 40 may be used. Even with such a configuration using a covering rubber, the RFID tag 40 can be adequately protected.
[0062] The RFID tag 40 covered by the protective member 43 is embedded in the tire 1 so that the direction in which the antenna extends, i.e., the longitudinal direction, is, for example, a tangential direction to the circumferential direction of the tire 1, i.e., a direction perpendicular to the paper surface in the cross-sectional views of FIGS. 1 and 2. The covering rubber sheets 431, 432 are embedded in the tire 1 so as to be aligned in the tire width direction. That is, in the manufacturing process, one surface of either one of the covering rubber sheets 431, 432 is attached to a component of the tire 1 before vulcanization, such as the shoulder pad 38 and the tread rubber 28. The RFID tag 40 covered by the protective member 43 is disposed between the shoulder pad 38 and the tread rubber 28 and the sidewall rubber 30. By adopting such an embodiment, even when the tire 1 is deformed, stress is unlikely to be applied to the RFID tag 40. Furthermore, the task of attaching the RFID tag 40 covered with the protective member 43 in the manufacturing process is simplified.
[0063] Here, in the process of attaching the RFID tag 40, the RFID tag 40 covered by the protective member 43 can be easily arranged in the above-mentioned direction by using the boundary between multiple rubber members, in this embodiment, the circumferential shape of the boundary B between the shoulder pad 38 and the tread rubber 28 (the inner circumferential shape of the tire radially inner end 28B of the tread rubber 28) shown in Fig. 4A as a reference. That is, as shown in Fig. 4A, the longitudinal direction of the covering rubber sheets 431, 432 covering the RFID tag 40 may be attached so as to substantially coincide with the tangent direction of the circumferential shape of the boundary B, using the circumferential shape of the boundary B as a reference.
[0064] 4B is a diagram showing a modified example of the manufacturing process, showing a case where covering rubber sheets 431, 432 covering the RFID tag 40 are attached while being bent so as to follow the circumferential shape of boundary portion B between the shoulder pad 38 and the tread rubber 28. At this time, covering rubber sheets 431, 432 made of raw rubber can also be attached while being deformed so as to follow the circumferential direction of boundary portion B. A flexible coil-shaped spring antenna or the like may be used as the antenna of RFID tag 40, so that the antenna also deforms following the deformation of covering rubber sheets 431, 432. By using these methods, the RFID tag 40 covered with the protective member 43 can be easily and accurately arranged in the above-mentioned direction without the need for any special marking.
[0065] 4C is a diagram showing an annular rubber sheet 50 as a modified example of the protective member. For example, the protective member is configured by sandwiching the RFID tag 40 between two annular covering rubber sheets. In this case, it is preferable to adopt a mode in which the entire circumference of the boundary portion B between the shoulder pad 38 and the tread rubber 28 is covered by the annular rubber sheet 50. This can generally assist in the joining between the rubber members, specifically, the joining between the shoulder pad 38 and the tread rubber 28.
[0066] 5 and 6 show modified examples of the tire 1 of the present embodiment. 5, the protective member 43 covering the RFID tag 40 is also disposed at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30. In this modified example, the protective member 43 covering the RFID tag 40 is disposed so as to straddle the sidewall rubber 30 and the tread rubber 28 at the boundary between the sidewall rubber 30 and the tread rubber 28. That is, the protective member 43 is attached so as to press the tire radial direction inner end 28B of the tread rubber 28, which has a tapered shape at the tire radial direction inner end in a cross section in the tire width direction, from the tire cavity side. The tire cavity side of the protective member 43 is covered by the shoulder pad 38. Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is not easily affected by stress because it is surrounded by multiple rubber members, specifically, the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30. Furthermore, by using the boundary between multiple rubber members, in this modified example, the boundary between the sidewall rubber 30 and the tread rubber 28 as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately. Furthermore, between the three rubber members, the position of the RFID tag 40 can be reasonably secured even after vulcanization, resulting in good uniformity.
[0067] 6, the protective member 43 covering the RFID tag 40 is also disposed at a position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect. In this modified example, the protective member 43 covering the RFID tag 40 is disposed so as to come into contact with the tire radially inner end 28B of the tread rubber 28, which has a tapered shape at its tire radially inner end in a cross section in the tire width direction. Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is not easily affected by stress because it is surrounded by multiple rubber members, specifically, the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30. Furthermore, by using the boundary between multiple rubber members, in this modified example, the boundary B between the shoulder pad 38 and the tread rubber 28, as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately.
[0068] It is preferable to place the RFID tag 40 at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 while being covered with the protective member 43 as described above, but it may also be placed directly at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 without being covered with the protective member 43. If the uncoated RFID tag 40 is placed directly at the intersection of the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30, the variation in thickness of the rubber material where the RFID tag 40 is placed is reduced, improving tire uniformity. Also, in the work of embedding the RFID tag 40 in such a position, the volume of the embedded object is small, making it easier to remove air. Also, by eliminating the process of covering the RFID tag 40 with a protective material, the work time is reduced.
[0069] In this embodiment, an RFID tag 40 is embedded in the tire as an electronic component, but the electronic component embedded in the tire is not limited to an RFID tag. For example, it may be various electronic components such as a sensor that performs wireless communication. In addition, since electronic components handle electrical information such as transmitting and receiving electrical signals, the presence of metal components in the vicinity may cause a decrease in performance. In addition, electronic components may be damaged by excessive stress. Therefore, the effect of the present invention can be obtained even when various electronic components are embedded in a tire. For example, the electronic components may be piezoelectric elements or strain sensors.
[0070] The tire 1 of the present embodiment provides the following advantages.
[0071] (1) The tire 1 according to this embodiment includes a plurality of rubber members constituting the tire 1 and an RFID tag 40, and the RFID tag 40 is disposed at a position where at least three rubber members intersect. This makes the RFID tag 40 less susceptible to the effects of stress. Also, by using the boundary between multiple rubber members, in this embodiment, the boundary B between the shoulder pad 38 and the tread rubber 28, as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, etc., and allows the RFID tag 40 to maintain its proper function.
[0072] (2) In the tire 1 according to this embodiment, the three rubber members are each annular rubber members formed into an annular shape. In this way, even if the three rubber members are annular rubber members that are tire constituent members that constitute the tire 1 having an annular shape, the above-mentioned effects can be obtained.
[0073] (3) The tire 1 of this embodiment has a shoulder pad 38 as a rubber member that is arranged on the outer surface side of the carcass ply 23 and on the inner cavity side of the tread rubber 28 and the sidewall rubber 30, and the RFID tag 40 is arranged at the position where the shoulder pad 38, the tread rubber 28, and the sidewall rubber 30 intersect. Even with this configuration, the above-mentioned effects can be obtained. Furthermore, by arranging the RFID tag 40 in such a position, good communication performance can be obtained.
[0074] (4) In the tire 1 according to this embodiment, at least a portion of the RFID tag 40 is covered with covering rubber sheets 431, 432, and the covering rubber sheets 431, 432 covering the RFID tag 40 are disposed at positions where at least three rubber members intersect. This can also assist in joining the rubber members together, in this embodiment, the joining of the shoulder pad 38 and the tread rubber 28.
[0075] (5) The three rubber members of tire 1 according to this embodiment include a first rubber member, a second rubber member arranged so as to cover a portion of the first rubber member and having a tapered end in a cross-sectional view in the tire width direction, and a third rubber member covering at least the boundary between the first rubber member and the second rubber member, and covering rubber sheets 431, 432 are arranged so as to straddle the first rubber member and the second rubber member at the boundary between the first rubber member and the second rubber member, and are covered by the third rubber member. This can also assist in joining between the rubber members, in this embodiment, the shoulder pad 38 as the first rubber member and the tread rubber 28 as the second rubber member.
[0076] (6) A manufacturing method for producing tire 1 according to this embodiment includes a step of attaching covering rubber sheets 431, 432 at the boundary between the first rubber member and the second rubber member so as to straddle the first rubber member and the second rubber member, and a step of attaching a third rubber member so as to cover covering rubber sheets 431, 432 attached to the boundary between the first rubber member and the second rubber member. This can also assist in joining between the rubber members, in this embodiment, the shoulder pad 38 as the first rubber member and the tread rubber 28 as the second rubber member.
[0077] (7) In the tire 1 according to this embodiment, the RFID tag 40 as an electronic component is covered with the annular rubber sheet 50, and the annular rubber sheet 50 covers the entire circumference of the boundary between the annular first rubber member and the annular second rubber member. This can generally assist in bonding between the first rubber member and the second rubber member. For example, it can generally assist in bonding between the shoulder pad 38 as the first rubber member and the tread rubber 28 as the second rubber member.
[0078] <Second embodiment> Next, a tire according to a second embodiment will be described with reference to the drawings. In the following description, the same components as those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.
[0079] FIG. 7 is an enlarged cross-sectional view showing the periphery of the embedded portion of the RFID tag 40 in the tire 1 of the present embodiment. 7, the RFID tag 40 (including a state where at least a part of it is covered by a protective member 43) is disposed at a position where at least three rubber members constituting the tire 1 intersect. More specifically, the tire 1 of this embodiment includes a second pad 36 as a first rubber member in this embodiment, a rim strip rubber 32 as a second rubber member in this embodiment disposed so as to cover a part of the tire outer surface side of the second pad 36, and a sidewall rubber 30 as a third rubber member in this embodiment covering at least a boundary portion between the second pad 36 and the rim strip rubber 32, and the RFID tag 40 is disposed at a position where the second pad 36, the rim strip rubber 32, and the sidewall rubber 30 intersect.
[0080] In this embodiment, more preferably, the RFID tag 40 is covered and held by a protective member 43 made of a covering rubber sheet, and this protective member 43 is arranged so as to straddle the boundary between the second pad 36 and the rim strip rubber 32. In other words, this protective member 43 is attached so as to press the tire radial direction outer end 32A of the rim strip rubber 32, which has a tapered shape at the tire radial direction outer end in a cross section in the tire width direction. The tire outer surface side of this protective member 43 is covered by the sidewall rubber 30.
[0081] Here, the second pad 36, the rim strip rubber 32, and the sidewall rubber 30 are each annular rubber members that constitute the annular tire 1. The protection member 43 that holds the RFID tag 40 is disposed so as to be in surface contact with the second pad 36, the rim strip rubber 32, and the sidewall rubber 30.
[0082] Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is surrounded by multiple rubber members, specifically, the second pad 36, the rim strip rubber 32, and the sidewall rubber 30, so that the RFID tag 40 is less susceptible to the effects of stress. Furthermore, by using the boundary between multiple rubber members, in this embodiment, the boundary between the second pad 36 and the rim strip rubber 32, as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, etc., and allows the function of the RFID tag 40 to be maintained appropriately.
[0083] In addition, when the modulus of the second pad 36 is taken as a standard, the sidewall rubber 30 preferably has a modulus 0.4 to 0.6 times that of the second pad 36. In addition, the first pad 35 preferably has a modulus 1.1 to 1.2 times that of the second pad 36. In addition, the second bead filler 222 preferably has a modulus 0.7 to 0.8 times that of the second pad. In addition, when the modulus of the second pad 36 is taken as a standard, the rim strip rubber 32 preferably has a modulus 0.8 to 1 times that of the second pad 36. In addition, the rubber sheet 37 preferably has a modulus 1.1 to 1.2 times that of the second pad 36. In other words, the modulus of the rubber sheet 37 is preferably approximately equal to the modulus of at least the portion (first pad 35) of the pad member 34 that covers the folded end 25A of the carcass ply 23. By setting the modulus in this range, a balance between the flexibility of the tire and the rigidity in the vicinity of the bead 11 can be maintained. The modulus refers to the 100% elongation modulus (M100) measured in an atmosphere of 23° C. in accordance with “3.7 Stress at a given elongation, S” of JIS K6251:2010.
[0084] FIG. 8 is a diagram showing the results of a simulation of the in-plane distribution of strain energy when the tire 1 of this embodiment is mounted on a rim and a 100% load is applied. In the enlarged cross-sectional view shown in Fig. 8, the region is divided into five regions according to the magnitude of the strain energy. Here, the region with the highest strain energy is level 5, the region with high strain energy is level 4, the region with slightly lower strain energy is level 3, the region with a further decrease in strain energy is level 2, and the region with the lowest strain energy is level 1. In Fig. 8, the regions are divided by thick dotted lines.
[0085] The location where the second pad 36, the rim strip rubber 32, and the sidewall rubber 30 intersect is generally in the level 1 to 2 region, which has little distortion energy and is a very favorable region for placing the RFID tag 40.
[0086] In addition, in the manufacturing process of tire 1, the process of attaching protective member 43 as a covering rubber sheet at the boundary between the first and second rubber members so as to straddle the first and second rubber members, and the process of attaching a third rubber member so as to cover the covering rubber sheet attached to the boundary between the first and second rubber members are the same as in the first embodiment.
[0087] In addition to the above advantages (1) to (2) and (4) to (7), the tire 1 of the present embodiment has the following advantages.
[0088] (8) In the tire 1 according to this embodiment, the RFID tag 40 is disposed at a position where the second pad 36, the rim strip rubber 32, and the sidewall rubber 30 intersect. This allows the RFID tag 40 to maintain its functionality without being affected by excessive distortion.
[0089] <Third embodiment> Next, a tire according to a third embodiment will be described with reference to the drawings. In the following description, the same components as those in the first and second embodiments are given the same reference numerals, and detailed description thereof will be omitted.
[0090] FIG. 9 is an enlarged cross-sectional view showing the periphery of the embedded portion of the RFID tag 40 in the tire 1 of the present embodiment. 9, the RFID tag 40 (including a state where at least a portion of it is covered by a protective member 43) is disposed at a position where at least three rubber members constituting the tire 1 intersect. More specifically, the tire 1 of this embodiment includes a second pad 36 as a first rubber member, a first pad 35 as a second rubber member, and a second bead filler 222 as a third rubber member, and the RFID tag 40 is disposed at a position where the second pad 36, the first pad 35, and the second bead filler 222 intersect.
[0091] Also in this embodiment, more preferably, the RFID tag 40 is covered and held by the protective member 43 made of a covering rubber sheet, and this protective member 43 is disposed so as to straddle the second pad 36 and the first pad 35 at the boundary between the second pad 36 and the first pad 35. That is, the protective member 43 is attached so as to press the tire radial direction outer end 35A of the first pad 35, the tire radial direction outer end of which is tapered in a cross-sectional view in the tire width direction. The tire cavity side of the protective member 43 is covered by the second bead filler 222.
[0092] Here, the second pad 36, the first pad 35, and the second bead filler 222 are each annular rubber members that constitute the annular tire 1. The protective member 43 that holds the RFID tag 40 is disposed so as to be in surface contact with the second pad 36, the first pad 35, and the second bead filler 222.
[0093] Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is not easily affected by stress because the RFID tag 40 is surrounded by multiple rubber members, specifically, the second pad 36, the first pad 35, and the second bead filler 222. Furthermore, by using the boundary between the multiple rubber members, in this modified example, the boundary between the second pad 36 and the first pad 35, as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately.
[0094] In addition, in the manufacturing process of tire 1, the process of attaching protective member 43 as a covering rubber sheet at the boundary between the first and second rubber members so as to straddle the first and second rubber members, and the process of attaching a third rubber member so as to cover the covering rubber sheet attached to the boundary between the first and second rubber members are the same as in the first embodiment.
[0095] 10 to 13 show modified examples of the tire 1 of the present embodiment. These modified examples are examples in which the three rubber members surrounding the RFID tag 40 are different. However, they have in common that the second pad 36 is used as one of the rubber members. In the first modified example shown in FIG. 10, the protective member 43 covering the RFID tag 40 is also disposed at a position where at least three rubber members constituting the tire 1 intersect. More specifically, the tire 1 according to the embodiment of this modified example is disposed at a position where the second pad 36, the first pad 35, and the second bead filler 222 intersect. In this modified example, the protective member 43 covering the RFID tag 40 is disposed so as to straddle the second bead filler 222 and the first pad 35 at the boundary between the second bead filler 222 and the first pad 35. That is, the protective member 43 is attached so as to press the tire radial direction outer end 35A of the first pad 35, the tire radial direction outer end of which is tapered in a cross section in the tire width direction. The tire outer surface side of the protective member 43 is covered by the second pad 36. Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is not easily affected by stress because the RFID tag 40 is surrounded by multiple rubber members, specifically, the second pad 36, the first pad 35, and the second bead filler 222. Furthermore, by using the boundary between the multiple rubber members, in this modified example, the boundary between the second bead filler 222 and the first pad 35 as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately.
[0096] In the second modified example shown in FIG. 11, the protective member 43 covering the RFID tag 40 is also disposed at a position where at least three rubber members constituting the tire 1 intersect. More specifically, the tire 1 according to the embodiment of this modified example is disposed at a position where the second bead filler 222, the rubber sheet 37, and the second pad 36 intersect. In this modified example, the protective member 43 covering the RFID tag 40 is disposed so as to straddle the second bead filler 222 and the rubber sheet 37 at the boundary between the second bead filler 222 and the rubber sheet 37. That is, the protective member 43 is attached so as to press the tire radial direction outer end 37A of the rubber sheet 37. The protective member 43 is covered on the tire outer surface side by the second pad 36. The rubber sheet 37 is formed slightly larger in the tire radial direction outer direction than the first modified example shown in FIG. 10. Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is not easily affected by stress because it is surrounded by multiple rubber members, specifically, the second bead filler 222, the rubber sheet 37, and the second pad 36. Furthermore, by using the boundary between the multiple rubber members, in this modified example, the boundary between the second bead filler 222 and the rubber sheet 37 as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately.
[0097] Fig. 12 is a diagram of the bead filler 22, the rubber sheet 37, and the protective member 43 during the manufacturing process of the tire 1 in Fig. 11, as viewed from the outside in the tire width direction. The rubber sheet 37 is attached to the bead filler 22 and joined at a joint portion 37C to form an annular shape. As shown in this figure, a protective member 43 covering an RFID tag 40 is attached to the boundary between the annular second bead filler 222 and the rubber sheet 37. Also, as shown in FIG. 12, in consideration of assisting the joining of the bead filler 22 and the rubber sheet 37, an additional rubber sheet 51 may be attached to the boundary between the second bead filler 222 and the rubber sheet 37. The number of additional rubber sheets 51 may be one or more. It is preferable that the protective member 43 and the additional rubber sheet 51 are disposed at equal intervals. In this embodiment, one protective member 43 and two additional rubber sheets 51 are disposed at intervals of 120°. In addition, when a plurality of electronic components are embedded in the tire 1, the additional rubber sheet 51 may be a rubber sheet covering the electronic components. The additional rubber sheet, like the protective member 43, is preferably unvulcanized raw rubber at the time of attachment. Such a configuration in which the additional rubber sheet 51 is attached is also applicable to the first and second embodiments.
[0098] In the third modified example shown in FIG. 13, the protective member 43 covering the RFID tag 40 is also disposed at a position where at least three rubber members constituting the tire 1 intersect. More specifically, the tire 1 according to the embodiment of this modified example is disposed at a position where the second pad 36, the first pad 35, and the rubber sheet 37 intersect. In this modified example, the protective member 43 covering the RFID tag 40 is disposed so as to straddle the second pad 36 and the first pad 35 at the boundary between the second pad 36 and the first pad 35. That is, the protective member 43 is attached so as to press the tire radial direction outer end 35A of the first pad 35, the tire radial direction outer end of which is tapered in a cross section in the tire width direction. The tire cavity side of the protective member 43 is covered by the rubber sheet 37. Even if the RFID tag 40 is placed in such a position, the RFID tag 40 is not easily affected by stress because the RFID tag 40 is surrounded by multiple rubber members, specifically, the second pad 36, the first pad 35, and the rubber sheet 37. Furthermore, by using the boundary between the multiple rubber members, in this modified example, the boundary between the second pad 36 and the first pad 35, as the reference for the placement position of the RFID tag 40, variation in the placement position of the RFID tag 40 is reduced. This reduces the possibility that the RFID tag 40 will be mistakenly placed in an undesirable position in terms of stress, distortion, and the like, and allows the function of the RFID tag 40 to be maintained appropriately.
[0099] As shown in the results of the in-plane distribution simulation of strain energy in Figure 8, even in the modified examples shown in Figures 9 to 13, the location where RFID tag 40 is placed is generally in the level 2 area, which has little strain energy and is a very preferable area for placing RFID tag 40.
[0100] In addition to the above advantages (1) to (2) and (4) to (7), the tire 1 of the present embodiment has the following advantages.
[0101] (9) In the tire 1 according to this embodiment, the RFID tag 40 is disposed at a position where three rubber members including the second pad 36 intersect. This allows the RFID tag 40 to maintain its functionality without being affected by excessive distortion.
[0102] <Fourth embodiment> Next, a tire according to a fourth embodiment will be described with reference to Figures 14 to 20. In the following description, the same components as those in the first to third embodiments are given the same reference numerals, and detailed description thereof will be omitted. This embodiment is particularly suitable when the antenna of the RFID tag 40 is a coil spring antenna.
[0103] The RFID tag 40 of this embodiment uses a coil-shaped spring antenna 421 with high communication performance and flexibility as an antenna. The spring antenna 421 is set to an antenna length optimized according to the frequency band to be used, etc.
[0104] In this embodiment, rubber is placed inside the spring antenna 421 before the RFID tag 40 is sandwiched between the two covering rubber sheets 431, 432 constituting the protective member 43. More preferably, the rubber is filled inside the spring antenna so that as little air as possible remains. The process and the reason for adopting the process will be described with reference to Figures 14 to 20.
[0105] 14 to 17, a state around the RFID tag 40 when no rubber is filled in the spring antenna 421 will be described as a reference example. Fig. 14 is a diagram showing cross sections of the spring antenna 421 and the covering rubber sheets 431 and 432 before the RFID tag 40 is sandwiched between the covering rubber sheets 431 and 432. Fig. 15 is a diagram showing cross sections of the spring antenna 421 and the covering rubber sheets 431 and 432 after the RFID tag 40 has been sandwiched between the covering rubber sheets 431 and 432.
[0106] 15, in this reference example, since rubber is not filled in spring antenna 421 beforehand, a certain amount of air 45 may remain in spring antenna 421 after it is sandwiched between covering rubber sheets 431, 432. If air remains in this way, the integrity between covering rubber sheets 431, 432 and spring antenna 421 will be insufficient, and when the tire deforms, spring antenna 421 will not follow the movement of the rubber, which may damage RFID tag 40 having spring antenna 421.
[0107] In this example, raw rubber before vulcanization is used as the covering rubber sheets 431, 432. Therefore, by pressing the covering rubber sheets 431, 432 from both sides, the covering rubber sheets 431, 432 are embedded to a certain extent into the spring antenna, as shown in Fig. 15. However, it takes a great deal of time and effort to embed the covering rubber sheets 431, 432 until they are completely embedded inside the spring antenna.
[0108] Even if the rubber sheet is driven in over a long period of time until it is completely embedded in the spring antenna, the distance L between the outer periphery of the spring antenna 421 and the outer surfaces of the covering rubber sheets 431 and 432 becomes very short as shown in Fig. 16. It is also difficult to stabilize the distance L, and localized thin portions may occur. This results in insufficient protection of the RFID tag 40 by the covering rubber sheets 431 and 432, and there is a possibility that the covering rubber sheets 431 and 432 may be damaged during vulcanization.
[0109] Therefore, in this embodiment, as shown in Figures 17 to 20, rubber is placed inside spring antenna 421 before RFID tag 40 is sandwiched between covering rubber sheets 431, 432. More preferably, rubber is filled inside spring antenna 421 so that as little air as possible remains. The drawings on the right side of Figures 17 to 20 show cross sections of spring antenna 421 and its surroundings.
[0110] FIG. 17 is a diagram showing the state before the rubber 46 is filled inside the spring antenna 421, and FIG. 18 is a diagram showing the state after the rubber 46 is filled inside the spring antenna 421. Rubber 46 is embedded so as to have approximately the same outer diameter as the outer circumferential surface of spring antenna 421. If rubber 46 protrudes beyond the outer circumferential surface of spring antenna 421, it is preferable to wipe off the protruding portion. In other words, it is preferable that the outer circumferential surface of rubber 46 is molded so as to be approximately flush with the outer circumferential surface of spring antenna 421. It is also possible to fill the inside of the spring antenna 421 with rubber 46 and to wrap the outer periphery of the spring antenna 421 thinly with rubber 46. On the other hand, wrapping the spring antenna 421 thickly with rubber 46 is not preferable because it reduces the flexibility of the spring antenna 421 and increases the width dimension formed by the covering rubber sheets 431 and 432 after the RFID tag 40 is sandwiched therebetween. The rubber 46 may be embedded so that its outer diameter is approximately the same as the inner circumferential surface of the spring antenna 421. It is desirable that the outer circumferential portion of the rubber 46 is located within the range from the inner circumferential surface to the outer circumferential surface of the spring antenna 421.
[0111] Here, in order to ensure the flexibility of spring antenna 421, a flexible rubber is used as rubber 46. However, in consideration of workability and the like, it is preferable to use a rubber with a higher modulus than covering rubber sheets 431 and 432 as rubber 46. Incidentally, unvulcanized rubber is preferably used as the rubber 46 disposed inside the spring antenna 421. By making the rubber 46 and the covering rubber sheets 431 and 432 unvulcanized rubber and vulcanizing them simultaneously, the integrity of the rubber 46, the covering rubber sheets 431 and 432, and the spring antenna 421 is improved. Also, it is more preferable that the rubber 46 and the covering rubber sheets 431 and 432 are made of the same type of rubber. In addition, in consideration of the flexibility of the spring antenna 421, rubber 46 may have a lower modulus than the covering rubber sheets 431 and 432. Also, rubber of approximately the same modulus or rubber of the same material may be used. Note that vulcanized rubber may be used as the rubber 46 disposed inside the spring antenna 421. It is also possible to use a rubber adhesive, a rubber filler, or the like. Various rubber materials can be used while ensuring flexibility and taking into consideration the need to minimize the amount of air remaining inside the spring antenna 421. Various methods can be used for arranging the rubber 46, but for example, it is also possible to inject the rubber into the spring antenna 421 using a syringe. In this case, a set appropriate amount of the rubber 46 may be filled using the syringe. Also, after filling a larger amount of the rubber 46, the portion protruding from the outer periphery of the spring antenna 421 may be wiped off.
[0112] FIG. 19 shows the RFID tag 40 having the spring antenna 421 filled with rubber 46 before it is sandwiched between the covering rubber sheets 431 and 432, and FIG. 20 shows the RFID tag 40 after it is sandwiched between the covering rubber sheets 431 and 432.
[0113] 20, according to this embodiment, since the spring antenna 421 is filled with the rubber 46 in advance, no air pocket exists between the covering rubber sheets 431 and 432. Therefore, since there is no need to worry about air pockets, the process of sandwiching the RFID tag 40 between the covering rubber sheets 431 and 432 is simplified. In addition, by disposing the rubber 46 inside the spring antenna 421, the integrity of the spring antenna 421, the rubber 46, and the covering rubber sheets 431 and 432 is improved, and when the tire deforms, the spring antenna 421 follows the movement of the rubber. Therefore, the durability of the RFID tag 40 having the spring antenna 421 is also improved.
[0114] Moreover, according to this embodiment, the distance L between the outer periphery of the spring antenna 421 and the outer surfaces of the covering rubber sheets 431 and 432 is stable. That is, the distance L is generally secured to be close to the thickness of the covering rubber sheets 431 and 432. Therefore, the RFID tag 40 is sufficiently protected by the covering rubber sheets 431 and 432. In this embodiment, the RFID tag 40 sandwiched between the covering rubber sheets 431, 432 is disposed between the rubber members, and then the green tire is vulcanized.
[0115] In this embodiment, the RFID tag 40, in which the spring antenna 421 is filled with rubber 46 in advance, is covered with covering rubber sheets 431 and 432, and is then placed between the rubber members. However, the RFID tag 40 in which the rubber 46 has been filled in advance inside the spring antenna 421 may be disposed between the rubber members without being covered with the covering rubber sheets 431 and 432 . In this way, by disposing the uncoated RFID tag 40 directly between the rubber members, the variation in thickness of the rubber member where the RFID tag 40 is sandwiched is reduced, improving the uniformity of the tire 1. In addition, since the rubber 46 is filled in advance inside the spring antenna 421, the rubber sheet 37 will not be excessively embedded in the spring antenna.
[0116] In addition to the above advantages (1) to (10), the tire according to this embodiment has the following advantages.
[0117] (11) In this embodiment, RFID tag 40 as an electronic component with communication function has spring antenna 421, and a step of placing rubber 46 inside spring antenna 421 is provided prior to the step of attaching RFID tag 40 to a rubber member. This makes it possible to easily assemble the RFID tag 40 without having to worry about air pockets during the process of sandwiching the spring antenna 421 of the RFID tag 40 between rubber members. (12) In this embodiment, the method includes a step of placing rubber 46 inside spring antenna 421 of RFID tag 40, which is an electronic component having a communication function; a step of sandwiching RFID tag 40 having spring antenna 421 in which rubber 46 is placed, between covering rubber sheets 431, 432; and a step of arranging RFID tag 40 sandwiched between covering rubber sheets 431, 432, between rubber members. This prevents air 45 from remaining inside the spring antenna 421. In addition, since there is no need to worry about air pockets, the task of sandwiching the RFID tag 40 between the covering rubber sheets 431 and 432 is also simplified. Furthermore, since the distance L between the outer periphery of the spring antenna 421 and the outer surfaces of the covering rubber sheets 431 and 432 is stable, the RFID tag 40 is sufficiently protected by the covering rubber sheets 431 and 432 .
[0118] (13) This embodiment includes a step of placing rubber 46 within the spring antenna 421 of the RFID tag 40, which is an electronic component having a communication function, and a step of attaching a rubber sheet 37 to the bead filler 22 so as to sandwich the uncoated RFID tag 40 between the rubber members. In this way, by directly sandwiching the uncoated electronic component between the rubber members, the variation in thickness of the rubber member in the portion where the RFID tag 40 is sandwiched is reduced, improving the uniformity of the tire 1. In addition, since the rubber 46 is filled in advance inside the spring antenna 421, the rubber sheet 37 will not be excessively embedded in the spring antenna.
[0119] The tire of the present invention can be used as various tires for passenger cars, light trucks, trucks, buses, etc., and is particularly suitable as a tire for trucks, buses, etc. The present invention is not limited to the above-described embodiment, and even if modifications and improvements are made within the scope of the present invention, they will still be included in the scope of the present invention. [Explanation of symbols]
[0120] 1. Tires 11...Bead 12…Tread 13…Sidewall 21…Bead core 22…Bead filler 221…First bead filler 222…Second bead filler 23…Carcass ply 24…Ply body 25…Ply turn-up section 26…Steel belt 28...Tread rubber 28B…Tire radial inner end 29…Inner liner 30...Sidewall rubber 31…Steel Chaher 32…Rim strip rubber 32A…Tire radial outer end 34...Pad member 35…First pad 35A…Tire radial outer end 36…Second pad 37…Rubber sheet 37A…Tire radial outer end 38…Shoulder pads 40…RFID tag 41…RFID chip 42…Antenna 421...Spring antenna 43...Protective material 431, 432...Rubber sheet 46…Rubber
Claims
1. A bead core; a bead filler extending outward in a radial direction of the tire from the bead core; a carcass ply having a ply turnup portion turned up around the bead core; A first pad provided on an outer side of a folded-up portion of the carcass ply and the bead filler in a tire width direction; A second pad provided to cover an outer side of the first pad in a tire width direction; A member constituting an outer surface of the tire that covers an outer side of the second pad in the tire width direction; and an electronic component disposed at a position where at least three rubber members intersect; The member constituting the outer surface of the tire covers the entire outer side of the second pad in the tire width direction, the at least three rubber members include the bead filler, the first pad, and the second pad; The electronic component is disposed at a position where the bead filler, the first pad, and the second pad intersect.
2. A method for producing the tire according to claim 1, comprising the steps of: At least a portion of the electronic component is covered with a coating rubber sheet, The covering rubber sheet is attached to the boundary between the second pad and the first pad. a step of attaching the second pad and the first pad so as to straddle the second pad and the first pad; and attaching the bead filler so as to cover the covering rubber sheet attached to the boundary portion between the second pad and the first pad.
3. A method for producing the tire according to claim 1, comprising the steps of: At least a portion of the electronic component is covered with a coating rubber sheet, The covering rubber sheet is placed at a boundary between the bead filler and the first pad. a step of attaching the bead filler and the first pad so as to straddle the bead filler and the first pad; and attaching the second pad so as to cover the covering rubber sheet attached to the boundary between the bead filler and the first pad.
4. A bead core; a bead filler extending outward in a radial direction of the tire from the bead core; a carcass ply having a ply turnup portion turned up around the bead core; A pad member provided on an outer side in a tire width direction of the folded-up portion of the carcass ply and the bead filler; a rubber sheet disposed between the bead filler and the pad member; A member constituting an outer surface of the tire that covers an outer side of the pad member in the tire width direction; and an electronic component disposed at a position where at least three rubber members intersect; The pad member includes a first pad provided on an outer side of the folded-up portion of the carcass ply and the bead filler in the tire width direction; A second pad provided to cover an outer side of the first pad in the tire width direction, The member constituting the outer surface of the tire covers the entire outer side of the second pad in the tire width direction, The rubber sheet is arranged to cover an end of the folded-up portion of the carcass ply from an inner side in the tire width direction, The at least three rubber members include the first pad, the second pad, and the rubber sheet, The electronic component is disposed at a position where the first pad, the second pad, and the rubber sheet intersect.
5. A method for producing the tire according to claim 4, comprising the steps of: At least a portion of the electronic component is covered with a coating rubber sheet, The covering rubber sheet is attached to the boundary between the second pad and the first pad. a step of attaching the second pad and the first pad so as to straddle the second pad and the first pad; and attaching the rubber sheet so as to cover the covering rubber sheet attached to the boundary between the second pad and the first pad.
Citation Information
Patent Citations
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