Pneumatic tires and methods for manufacturing pneumatic tires
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- THE YOKOHAMA RUBBER CO LTD
- Filing Date
- 2011-12-28
- Publication Date
- 2026-07-02
Abstract
Description
Technical field
[0001] The present invention relates to a pneumatic tire. background
[0002] Reducing the rolling resistance of a pneumatic tire is beneficial for a vehicle's fuel consumption. Methods for reducing tire rolling resistance exist, such as using a silica rubber compound for the tread. State of the art documents
[0003] Non-Patent Document 1: Recent Technical Trends in Tires, Akimasa DOI, Journal of the Society of Rubber Industry, Sep. 1998, Vol. 71, pp. 588–594 Summary
[0004] Problem to be solved by the invention: While the method for reducing the rolling resistance of pneumatic tires described in non-patent document 1 provides an improvement in the material, it is also possible to reduce the rolling resistance by modifying the structure of the pneumatic tire. In view of the foregoing, an object of the present invention is to provide a structure by which the rolling resistance of a pneumatic tire is reduced.
[0005] Means of solving the problem: A means of solving the problem described above is a pneumatic tire comprising: a cylindrical annular structure with a plurality of through holes; a rubber layer that becomes a tread section and is present along a circumferential direction of the annular structure on an outer side of the annular structure; and a carcass section comprising rubber-covered fibers and provided at least on both sides in a direction parallel to the central axis of the cylindrical structure comprising the annular structure and the rubber layer.
[0006] One means of solving the problem described above is a pneumatic tire comprising: a cylindrical annular structure with a plurality of through-holes; a rubber layer forming a tread section and present along a circumferential direction of the annular structure on an outer surface of the annular structure; a groove present on an outer surface in the radial direction of the rubber layer; and a carcass section comprising rubber-covered fibers and provided on at least both sides in a direction parallel to a central axis of the cylindrical structure comprising the annular structure and the rubber layer. The opening ratio of the through-holes in at least one region where the groove is provided is smaller than in a region near the region where the groove is provided.
[0007] Using the above-described means, the proportion of the total opening area of the through holes relative to a surface of the outside in the radial direction, in a case where the annular structure does not have the through holes, is preferably not less than 1% and not more than 30% in an area near a circumferential groove and not less than 0.5% and not more than 15% in an area where the circumferential groove is provided.
[0008] Using the means described above, the cross-sectional area of one of the through holes is preferably not less than 0.1 mm². 2 and no more than 100 mm 2 .
[0009] Using the means described above, the sum of the area of the through holes preferably amounts to not less than 0.5% and not more than 30% of the outer surface in the radial direction of the ring-shaped structure.
[0010] In the above-described device, the outer surface of the rubber layer and the outer surface of the ring-shaped structure, except for a grooved section of the rubber layer, preferably run parallel to the central axis.
[0011] In the above-described device, the ring-shaped structure is preferably arranged further outwards in a radial direction of the structure than the carcass section.
[0012] In the above-described agent, the ring-shaped structure is preferably a metal.
[0013] In the above-described device, a dimension in the direction parallel to the central axis of the ring-shaped structure preferably amounts to not less than 50% and not more than 95% of the total width in the direction parallel to the central axis of the pneumatic tire.
[0014] One means of solving the problem described above consists of a method for manufacturing a pneumatic tire, wherein the pneumatic tire has a rubber layer that forms a tread section and is provided on the outer surface of a cylindrical and annular structure. The method comprises the following steps: providing a cylindrical annular structure having a plurality of through holes, wherein the opening ratio of the through holes in a region of the tread section where a groove is provided is smaller than in a region near the region where the groove is provided; manufacturing a tire blank by applying unvulcanized rubber to an outer surface in the radial direction.to an inner side in the radial direction of the ring-shaped structure; and guiding the rubber on the inner side in the radial direction of the ring-shaped structure through the through holes to the outer side in the radial direction by applying pressure and heat to the tire blank from the inner side in the radial direction of the tire blank, after the tire blank has been placed in a vulcanizing mold.
[0015] Effect of the invention: The present invention can provide a structure by which the rolling resistance of a pneumatic tire is reduced. Brief description of the drawings
[0016] Fig. Figure 1 is a meridian cross-sectional view of a tire according to a first embodiment.
[0017] Fig. Figure 2-1 is a perspective view of a ring-shaped structure in the tire according to the first embodiment.
[0018] Fig. 2-2 is a top view of the ring-shaped structure in the tire according to the first embodiment.
[0019] Fig. Figure 3 is an enlarged view of a carcass section in the tire according to the first embodiment.
[0020] Fig. Figure 4 shows a meridian cross-sectional view of the ring-shaped structure and a rubber layer.
[0021] Fig. Figure 5-1 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0022] Fig. Figure 5-2 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0023] Fig. Figure 5-3 is a top view illustrating a modification example of a ring-shaped structure with depressions and projections on both edges in the width direction.
[0024] Fig. Figure 5-4 is a top view illustrating a modification example of a ring-shaped structure with depressions and projections on both edges in the width direction.
[0025] Fig. Figure 6 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0026] Fig. Figure 7 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0027] Fig. Figure 8 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0028] Fig. Figure 9 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0029] Fig. Figure 10 is a drawing illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment.
[0030] Fig. Figure 11 is an explanatory drawing for calculating the opening ratio of the through holes.
[0031] Fig. Figure 12 is an explanatory drawing for calculating the opening ratio of the through holes.
[0032] Fig. Figure 13 is an explanatory drawing for calculating the opening ratio of the through holes.
[0033] Fig. Figure 14 is an explanatory drawing for calculating the opening ratio of the through holes.
[0034] Fig. Figure 15 is a diagram showing the relationship between the opening ratio and the breaking force ratio.
[0035] Fig. Figure 16-1 is a perspective view of a ring-shaped structure in the tire according to a second embodiment.
[0036] Fig. Figure 16-2 is a perspective view of a modification example of the ring-shaped structure contained in the tire according to the second embodiment.
[0037] Fig. Figure 17 is an explanatory drawing illustrating a distribution of the through holes of the ring-shaped structure in the tire according to the second embodiment.
[0038] Fig. Figure 18 is an explanatory drawing illustrating a distribution of the through holes of the ring-shaped structure in the tire according to the second embodiment.
[0039] Fig. Figure 19 is an explanatory drawing illustrating a distribution of the through holes of the ring-shaped structure in the tire according to the second embodiment.
[0040] Fig. Figure 20 is an explanatory drawing illustrating a distribution of the through holes of the ring-shaped structure in the tire according to the second embodiment.
[0041] Fig. Figure 21 is a top view illustrating a modification example of the ring-shaped structure in the tire according to the second embodiment.
[0042] Fig. Figure 22 is a top view illustrating a modification example of the ring-shaped structure in the tire according to the second embodiment.
[0043] Fig. 23-1 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0044] Fig. 23-2 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0045] Fig. 24-1 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0046] Fig. 24-2 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0047] Fig. 25-1 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0048] Fig. 25-2 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0049] Fig. 26-1 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0050] Fig. 26-2 is a schematic representation illustrating a state in which the tire is vulcanized in a vulcanizing mold.
[0051] Fig. Figure 27 is a flowchart illustrating the steps of a process for producing the ring-shaped structure in the tire.
[0052] Fig. Figure 28-1 is an explanatory drawing illustrating one step of the process for producing the ring-shaped structure.
[0053] Fig. Figure 28-2 is an explanatory drawing illustrating one step of the process for producing the ring-shaped structure.
[0054] Fig. Figure 28-3 is an explanatory drawing illustrating one step of the process for producing the ring-shaped structure.
[0055] Fig. Figure 28-4 is a cross-sectional view showing the thickness of a welded section. Detailed description
[0056] One embodiment of the present invention is described in detail below, with reference to the drawings. However, the present invention is not limited to the description given in this embodiment. Furthermore, the components described below include those components that can be readily deduced by a person skilled in the art, as well as components that are essentially identical to those described here. In addition, the components described below can be combined with one another as required. First embodiment
[0057] If eccentric deformation is increased to its limit to reduce the rolling resistance of a pneumatic tire (hereinafter referred to as a "tire" as needed), the contact area between the tire and the road surface decreases, and the contact pressure increases. Consequently, the viscoelastic energy loss due to deformation of a tread section increases, which in turn leads to increased rolling resistance. The inventors focused their attention on this issue and sought to reduce rolling resistance and increase steering stability by ensuring a sufficient contact area between the tire and the road surface while maintaining eccentric deformation. Eccentric deformation is a one-dimensional type of deformation in which a tread ring (zenith area) of the tire is displaced perpendicularly while maintaining the tire's round shape.To ensure the contact patch between the tire and the road surface, and to maintain eccentric deformation, this tire design, for example, uses a structure that has a cylindrical, ring-shaped form made from a thin metal plate. A layer of rubber is applied to the outer surface of this ring-shaped structure along one circumferential direction. This rubber layer forms the tread section of the tire.
[0058] Fig. Figure 1 is a meridian cross-sectional view of a tire according to the first embodiment. Fig. Figure 2-1 is a perspective view of a ring-shaped structure in the tire according to the first embodiment. Fig. 2-2 is a top view of the ring-shaped structure in the tire according to the first embodiment. Fig. Figure 3 is an enlarged view of a carcass section in the tire according to the first embodiment. As in Fig. The tire shown in 1 is the tire 1 a ring-shaped structure. An axis passing through the center of the ring-shaped structure is the central axis (Y-axis) of the tire. 1 When in use, the inside of the tire 1 filled with air.
[0059] The tire 1 It rotates, with the central axis (Y-axis) serving as the axis of rotation. The Y-axis is the central axis and the axis of rotation of tires. 1 An X-axis is perpendicular to the Y-axis (the central axis (axis of rotation) of the tire). 1 ) running axis and runs parallel to a road surface with which tires 1 It has ground contact. A Z-axis is an axis perpendicular to the Y-axis and the X-axis. A lateral direction of the tire. 1 is a direction parallel to the Y-axis. A radial direction of tires 1is a direction that intersects the Y-axis and runs perpendicular to it. Additionally, a circumferential direction centered on the Y-axis is a circumferential direction of the pneumatic tire. 1 (the one marked by the arrow “CR” in Fig. 1 (indicated direction).
[0060] As in Fig. As shown in 1, the tire 1 a cylindrical ring-shaped structure 10 , a layer of rubber 11 and a carcass section 12 on. The ring-shaped structure 10 is a cylindrical element. The rubber layer 11 is along the circumferential direction of the ring-shaped structure 10 on an outside 10so the ring-shaped structure 10 present and forms the tread section of tires 1 As in Fig. As shown in section 3, the carcass section 12 Fibers 12F , which are made with rubber 12Rare covered. In this embodiment, as in Fig. 1 shown, the carcass section 12 on an inner side in the radial direction of the ring-shaped structure 10 present and connects both bead sections 13 In other words, the carcass section 12 between the two bead sections 13 and 13 throughout. It should be noted that, although the carcass section 12 on both sides in the width direction of the ring-shaped structure 10 The carcass section is present. 12 between the two bulge sections 13 and 13 It does not have to be continuous. Therefore, as in Fig. 3 shown, sufficient if the carcass section 12 on both sides in the direction (the width direction) parallel to the central axis (Y-axis) of the cylindrical structure 2 is present, which at least has a ring-shaped structure 10and the rubber layer 11 exhibits.
[0061] Regarding the tire 1 indicate, in a meridian cross-section of structure 2 , an outside 11so (tread surface of the tire) 1 ) the rubber layer 11 and the outside 10so the ring-shaped structure 10 preferably the same shape and are parallel (including dimension and tolerance) except for sections where a groove S is formed in the running surface.
[0062] The in Fig. 2-1 illustrated ring-shaped structure 10 is a metal structure. In other words, the ring-shaped structure 10 Made of a metal material. This is responsible for the ring-shaped structure. 10 The metal material used preferably has a tensile strength of not less than 450 N / m². 2 and no more than 2,500 N / m 2 up, preferably no less than 600 N / m2 and no more than 2,400 N / m 2 and preferably not less than 800 N / m 2 and no more than 2,300 N / m 2 If the tensile strength is within the range described above, sufficient strength and stiffness of the ring-shaped structure can be achieved. 10 This ensures the necessary toughness is maintained. Consequently, sufficient pressure resistance of the ring-shaped structure can be achieved. 10 This must be ensured. It is sufficient that the tensile strength of the metal material used for the ring-shaped structure is sufficient. 10The material that can be used lies within the range described above; however, spring steel, high-strength steel, stainless steel, or titanium (including titanium alloys) is preferably used. Of these, stainless steel is preferred because it has high corrosion resistance and is easy to manufacture with a tensile strength within the range described above.
[0063] A compressive strength parameter is calculated as the product of the tensile strength (MPa) and the thickness (mm) of the ring-shaped structure. 10 The pressure resistance parameter is defined as a parameter that describes the resistance to the internal pressure of the gas with which the tire is inflated. 1The pressure resistance parameter is set so that it is not less than 200 and not more than 1,700, and preferably not less than 250 and not more than 1,600. If it is within this range, the maximum operating pressure of the tires can be determined. 1 This is ensured and sufficient safety is guaranteed. Furthermore, within the area described above, it is not necessary to determine the thickness of the ring-shaped structure. 10 to increase, and it is also not necessary to use a material with high tensile strength, as is preferred in mass production. Resistance to repeated bending can be achieved for the ring-shaped structure. 10 This can be ensured because it is not necessary to determine the thickness of the ring-shaped structure. 10 to increase. Furthermore, the ring-shaped structure 10 and the tire 1They can be manufactured at low cost because it is not necessary to use a material with high tensile strength. When used for a passenger car, the pressure resistance parameter is preferably not less than 200 and not more than 1,000, and more preferably not less than 250 and not more than 950. When used as a truck / bus tire (LB tire), the pressure resistance parameter is preferably not less than 500 and not more than 1,700, and more preferably not less than 600 and not more than 1,600.
[0064] During the production of the ring-shaped structure 10 Preferably, a martensitic stainless steel of class JIS G4303 is used, or alternatively, ferritic stainless steel, austenitic stainless steel, austenitic-ferritic two-phase stainless steel, or precipitation-hardened stainless steel. The use of such a stainless steel results in a ring-shaped structure. 10with superior tensile strength and toughness. Furthermore, of the stainless steels described above, precipitation-hardened stainless steel (SUS631 or SUS632J1) is preferred.
[0065] As in Fig. 2-1 and Fig. As shown in 2-2, the ring-shaped structure 10 a plurality of through holes 10H on, which penetrate an inner circumferential surface and an outer circumferential surface thereof. The rubber layer 11 is located on the outside in the radial direction and / or on the inside in the tire radial direction of the ring-shaped structure 10 attached. The rubber layer 11 is connected to the ring-shaped structure by means of a chemical bond 10 on the ring-shaped structure 10 attached. The through holes 10H represent an effect of strengthening the physical bond between the ring-shaped structure 10 and the rubber layer 11ready. This increases the bond strength with the ring-shaped structure. 10 increased by chemical and physical effects (anchoring effects), and as a result, the ring-shaped structure becomes 10 reliably with the rubber layer 11 attached. This leads to improved tire durability. 1 .
[0066] A cross-sectional area of one of the through holes 10H preferably not less than 0.1 mm 2 and no more than 100 mm 2 , preferably more than 0.12 mm 2 and no more than 80 mm 2 and even more preferably no less than 0.15 mm 2 and no more than 70 mm 2 If it lies within this range, irregularities in the carcass section will be detected. 12The effect is suppressed, and adhesive bonding, particularly chemical bonding, can be sufficiently employed. Furthermore, if it lies within the range described above, the physical effect described above, especially the anchoring effect, is most effective. Due to these effects, the bond between the ring-shaped structure can be... 10 and the rubber layer 11 be reinforced.
[0067] Regarding the shape of the through holes 10H There are no restrictions, however a circular or elliptical shape is preferred (in this embodiment the shape is circular). Furthermore, the equivalent diameter of the through holes is 4 × A / C. 10H (where C is the circumference of the through holes) 10H is and A is the opening area of the through holes 10H (is) preferably not less than 0.5 mm and not more than 10 mm. The through holes 10HThey preferably have a circular shape and a diameter of no less than 1.0 mm and no more than 8.0 mm. Within this range, physical and chemical bonds can be effectively used, and therefore the bonding between the ring-shaped structure is preferred. 10 and the rubber layer 11 stronger. As described below, the equivalent diameter or diameter of all through holes must be 10H They will not be the same.
[0068] A sum of the area of the through holes 10H preferably not less than 0.5% and not more than 30%, more preferably not less than 1.0% and not more than 20%, and even more preferably not less than 1.5% and not more than 15% of a surface of the outside in the radial direction of the ring-shaped structure 10 If it lies within this range, the strength of the ring-shaped structure can be increased. 10This is ensured while effectively utilizing physical and chemical bonds. Consequently, the bond between the ring-shaped structure is 10 and the rubber layer 11 stronger and the necessary stiffness of the ring-shaped structure 10 This can be ensured. As described below, the spacing of the through holes can be adjusted. 10H be the same or different. By using such a configuration, the tire's contact patch can be adjusted. 1 can be controlled.
[0069] The ring-shaped structure 10 can be achieved by joining the short sides of a rectangular sheet material into which the majority of through holes have been cut. 10H The ring-shaped structure was created by stamping and subsequent welding. 10 They can be produced in a relatively simple way. It should be noted that the process for producing the ring-shaped structure...10 is not limited to this and the ring-shaped structure 10 for example, it can be produced by forming a plurality of holes in the outer circumferential section of a cylinder and then milling the interior of the cylinder.
[0070] The outside 10so the ring-shaped structure 10 and the inside 11si the rubber layer 11 touch each other. In this embodiment, the ring-shaped structure 10 and the rubber layer 11 attached using, for example, an adhesive. Such a structure allows force to be transferred between the ring-shaped structure. 10 and the rubber layer 11 mutually transferred. Means for fastening the ring-shaped structure. 10 and the rubber layer 11 are not limited to adhesives. Furthermore, the ring-shaped structure 10Preferably not free to the outside in the radial direction of the rubber layer. Such a configuration results in the ring-shaped structure 10 and the rubber layer 11 are more reliably attached. Furthermore, the ring-shaped structure 10 in the rubber layer 11 be embedded. In such a case, the ring-shaped structure can 10 and the rubber layer 11 They can be connected more reliably.
[0071] The rubber layer 11 It comprises a rubber material, which may consist of synthetic rubber, natural rubber, or a mixture thereof, and carbon, SiO2, or the like, which is added to the rubber material as a reinforcing material. The rubber layer 11 is an endless ribbon-like structure. As in Fig. As shown in 1, in this embodiment the rubber layer 11a plurality of grooves (main grooves) S in an outer surface 11so on. The rubber layer 11 It may also have tread grooves in addition to the grooves S.
[0072] The carcass section 12 is a reinforcing element that, together with the ring-shaped structure 10 as a pressure vessel during tire inflation 1 It is powered by air. The carcass section 12 and the ring-shaped structure 10 support the load that is placed on the tires 1 due to the internal pressure of the air inside the tire 1 fills, acts upon, and withstands the dynamic forces acting on the tires 1 to act during the journey. In this embodiment, an inner core is used. 14 on an inner side of the carcass section 12 of tires 1 present. The inner soul. 14 suppresses the escape of air from the inside of the tire1 fills each end of the carcass section. 12 has a bulge section 13 on its inner side in a radial direction. The bead sections 13 fit with a rim of a wheel on which the tire 1 It is appropriate to assemble it. It should be noted that the carcass section 12 can be mechanically connected to the rim of the wheel.
[0073] Fig. Figure 4 is a meridian cross-sectional view of the ring-shaped structure. 10 and the rubber layer 11 An elastic modulus of the ring-shaped structure 10 The pressure is preferably not less than 70 GPa and not more than 250 GPa, and more preferably not less than 80 GPa and not more than 230 GPa. Furthermore, the thickness tm of the ring-shaped structure is... 10Preferably not less than 0.1 mm and not more than 0.8 mm. If the values are within this range, resistance to repeated bending can be ensured while simultaneously guaranteeing compressive strength. A product of the modulus of elasticity and the thickness tm of the ring-shaped structure. 10 (referred to as “stiffness parameter”) is preferably not less than 10 and not more than 500, and more preferably not less than 15 and not more than 400.
[0074] By configuring the stiffness parameter so that it lies within the range described above, the stiffness of the ring-shaped structure will be increased. 10 increased in the meridional cross-section. As a result, when the tire 1 is filled with air and when the tire 1 When the ground comes into contact with a road surface, deformations occur due to the ring-shaped structure. 10in meridian cross-section of the rubber layer 11 (Tread section) are suppressed. Therefore, a viscoelastic energy loss of the tire is prevented. 1 due to deformations. Furthermore, by configuring the stiffness parameter so that it lies within the range described above, the stiffness of the ring-shaped structure is increased. 10 reduced in the radial direction. Consequently, the tread area of tires is reduced. 1 in a ground contact area between tires 1 and deforms flexibly against the road surface, just like conventional pneumatic tires. This function makes the tire more flexible. 1 Eccentric deformation occurs, while local concentrations of stress and strain in the ground contact area are avoided, thus distributing the load across the ground contact area. As a result, local deformations of the rubber layer are minimized. 11suppressed in the ground contact area, which results in the ground contact area of the tire being reduced. 1 This ensures that rolling resistance is reduced.
[0075] Furthermore, the tire 1 , due to the high stiffness of the ring-shaped structure 10 within the plane and since the ground contact area of the rubber layer 11 This ensures that the ground contact length is maintained in the circumferential direction. Therefore, the lateral forces resulting from the application of a rudder angle increase. Consequently, the tire 1 achieve high curve stiffness. Furthermore, if the ring-shaped structure... 10 is made of metal, the majority of the air that fills the inside of the tire 1 is filled, not by the ring-shaped structure 10 escape. This is advantageous because it allows the air pressure of the tires to escape. 1This can be better regulated. Therefore, a decrease in tire pressure can be prevented. 1 even if the tire 1 so that the tire 1 is not filled with air for an extended period of time.
[0076] The distance tr (thickness of the rubber layer) 11 ) between the outside 10so the ring-shaped structure 10 and the outside 11so the rubber layer 11 The distance is preferably not less than 3 mm and not more than 20 mm. By configuring the distance tr to lie within such a range, excessive deformation of the rubber layer can be prevented. 11 Suppressed in curves, while simultaneously ensuring driving comfort. The direction is parallel to the central axis (Y-axis) of the ring-shaped structure. 10or, in other words, a dimension Wm (width of the ring-shaped structure) in the latitudinal direction of the ring-shaped structure 10 preferably is not less than 50% (W × 0.5) and not more than 95% (W × 0.95) of the total width (in a condition in which the tire 1 mounted on a wheel with a rim width specified by JATMA and inflated to 300 kPa) in the direction parallel to the central axis (Y-axis) of the tire 1 , who in Fig. Figure 1 is shown. If Wm is less than W × 0.5, the stiffness in the meridian cross-section of the ring-shaped structure is 10Insufficient, which leads to a reduction in the area that maintains the eccentric deformation with respect to the tire width. Consequently, the effect of reducing rolling resistance can be diminished and cornering stiffness can decrease. Furthermore, if Wm exceeds W × 0.95, compression deformations in the direction of the central axis (Y-axis) of the annular structure can occur in the tread section. 10 during ground contact, and this can lead to deformation of the ring-shaped structure. 10 By configuring Wm such that W × 0.5 ≤ Wm ≤ W × 0.95, the curve stiffness can be maintained while the rolling resistance is reduced, and deformation of the ring-shaped structure can also be prevented. 10 be suppressed.
[0077] Regarding the tire 1 points in the Fig. 1. The meridian cross-section shown is the outer side. 11so the rubber layer 11or, in other words, the profile of the tread surface, excluding the sections where the groove S is formed (in this case the main grooves Sc), preferably has the same shape as the outside. 10so the ring-shaped structure 10 Because of such a configuration, when the tire 1 when it comes into contact with the ground or rolls, the rubber layer 11 (tread section) and the ring-shaped structure 10 deformed in essentially the same way. Therefore, deformation of the rubber layer 11 of the tire 1 reduced, which leads to a decrease in viscoelastic energy loss and a further reduction in rolling resistance.
[0078] If the outside 11so the rubber layer 11 and the outside 10so the ring-shaped structure 10 outwards in the radial direction of the tire 1protrude, or alternatively inwards in the radial direction of the tire 1 Protruding, the pressure distribution in the ground contact area of the tire will change. 1 uneven. Consequently, local concentrations of stress and strain can be generated in the ground contact area, leading to local deformation of the rubber layer. 11 can occur in the ground contact area. In this embodiment, the tire exhibits 1 , as in Fig. 3 shown, the outside 11so the rubber layer 11 (the tread surface of the tire) 1 ) and the outside 10so the ring-shaped structure 10 the same shape (preferably parallel) and are also preferably parallel (including dimension and tolerance) to the central axis (Y-axis) of the rubber layer 11 and the ring-shaped structure 10 (i.e., the structure 2Such a structure can improve the ground contact area of the tire. 1 so that it is essentially flat. Regarding the tire... 1 The pressure distribution in the ground contact area is uniform, and therefore local concentrations of load and stress in the ground contact area are suppressed, preventing local deformation of the rubber layer. 11 This is suppressed in the ground contact area. Consequently, a reduction in viscoelastic energy loss is achieved, and thus also a reduction in the rolling resistance of tires. 1 Furthermore, the tire 1 local deformation of the rubber layer 11 This is suppressed in the ground contact area, thus ensuring the ground contact area and simultaneously guaranteeing the ground contact length in the tire's circumferential direction. Therefore, this can be achieved with the tire. 1 Curve stiffness must also be ensured.
[0079] In this embodiment, the shape of the rubber layer is different. 11 There are no particular restrictions in the meridian cross-section, provided that the outside 11so the rubber layer 11 and the outside 10so the ring-shaped structure 10 run parallel to the central axis (Y-axis). For example, the shape of the rubber layer can 11 The meridian cross-section exhibits a trapezoidal or parallelogram shape. This is the shape of the rubber layer. 11 In the meridian cross-section, if trapezoidal, then an upper or lower base side of the trapezoid can be the outer side. 11so the rubber layer 11 In both cases, it is sufficient if only the section of the ring-shaped structure is affected. 10 parallel to the profile of the tread surface of tires 1The structure runs (except for the sections where the groove is formed). Modification examples of the ring-shaped structure are given below. 10 described. Modification examples of the ring-shaped structure
[0080] Fig. 5-1 and Fig. Figures 5-2 are drawings illustrating a modification example of the ring-shaped structure in the tire according to the first embodiment. Fig. Figure 5-2 is a top view of the ring-shaped structure; arrow C indicates the circumferential direction of a ring-shaped structure. 10a an; and W indicates the latitude direction (the same below). In the ring-shaped structure described above. 10 of the tire 1 Both edges on the sides are formed in the width direction so that they are straight, however, as with the ring-shaped structure 10a In this modification example, both edges on the sides can have indentations and protrusions in the width direction. 10Tbe in a sawtooth shape. The in Fig. The rubber layer shown in Figure 3 is located on the outside in the radial direction of the ring-shaped structure. 10a attached, with the recesses and protrusions 10T to serve to strengthen the bond between the ring-shaped structure 10a and the rubber layer 11 to strengthen. In particular, the depressions and protrusions reinforce 10T the physical bond and increase the contact area with the rubber layer 11 As a result, the adhesive strength between the rubber layer can be reduced. 11 and the ring-shaped structure 10a to be increased. Therefore, the ring-shaped structure 10a with the depressions and protrusions 10T preferred because the bond with the rubber layer 11 It is more reliable and its durability is improved. Furthermore, the indentations and protrusions can be... 10Twhich extend across both edges in the latitudinal direction of the ring-shaped structure 10a The acting compressive stress is reduced, and therefore a yielding in the circumferential direction of the ground contact area of the tire can occur. 1 This is suppressed. This leads to a longer tire lifespan. 1 The depressions and protrusions 10T may have a uniform spacing, however the depressions and protrusions 10T , if uniform harmonics are generated, preferably an uneven spacing.
[0081] Fig. 5-3 and Fig. Figures 5-4 are top views illustrating a modification example of a ring-shaped structure with depressions and projections on both edges in the lateral direction. As in a Fig. 5-3 illustrated ring-shaped structure 10a' can depressions and protrusions 10T'They are formed from continuous semicircles. Depending on the material of the carcass section. 12 or the rubber layer 11 of the tire 1 Can an edge of the sawtooth shape lead to problems in the carcass section? 12 or in the rubber layer 11 (due to the cutting action) during use over an extended period, mechanical stresses accumulate due to deformations that occur when the tire 1 rolls. As a result, the durability of the carcass section can be affected. 12 or the rubber layer 11 decrease. In such a case, the in Fig. 5-3 depicted depressions and protrusions 10T' preferred.
[0082] Furthermore, as in the Fig. 5-4 shown ring-shaped structure 10a'' , depressions and protrusions 10T''exhibit a wave-like shape. This occurs when there is a decrease in the durability of the ring-shaped structure. 10a due to repeated bending, because the indentations of the depressions and protrusions 10T (e.g. valleys) that have a sawtooth shape like the one in Fig. 5-2 shown, are sharp (varying depending on the material and the thickness of the ring-shaped structure). 10a ), in addition, the in Fig. 5-4 depicted depressions and protrusions 10T'' preferred.
[0083] Fig. 6 to Fig. Figure 10 shows examples of modifications to the ring-shaped structure in the tire according to the first embodiment. These ring-shaped structures are preferably selected for use based on the properties required by the tire. In a ring-shaped structure 10b , which in Fig. Figure 6 shows a majority of the through holes. 10Harranged in the width direction (the direction indicated by the arrow “H”), and a majority of the through holes 10H is arranged offset in the circumferential direction (the direction indicated by arrow "C"). Compared to the ring-shaped structure 10 from Fig. 2-2 can be the distance between the through holes 10H (distance between six adjacent holes) in the ring-shaped structure 10b They must be formed uniformly. Therefore, a maximum density of through holes can be achieved. 10H This can be achieved when viewed from a flat surface. If greater adhesion strength is desired, the ring-shaped structure is used. 10b preferred.
[0084] The spacing of the majority of through holes 10H is larger in the width direction than in the circumference direction in a ring-shaped structure 10c , which in Fig. Figure 7 shows this ring-shaped structure. 10cThis is suitable when greater flexural stiffness in the width direction is desired. For example, increasing the flexural stiffness in one tread cross-sectional direction reduces road noise in the mid-frequency range (around 300 Hz).
[0085] Therefore, the ring-shaped structure 10c Suitable when reduced road noise in the mid-frequency range is desired.
[0086] The spacing of the majority of through holes 10H is larger in the circumferential direction than in the lateral direction in a ring-shaped structure 10d , which in Fig. 8 is shown, which is the opposite of the arrangement in the Fig. 7 shown ring-shaped structure 10c is. The ring-shaped structure 10dThis design is suitable when greater circumferential bending stiffness is desired. For example, increasing the circumferential bending stiffness of the tread improves steering stability. Therefore, the ring-shaped structure is ideal. 10d Suitable when improved steering stability is desired.
[0087] The spacing of the majority of through holes 10H is constant in the circumferential direction and varies in the lateral direction in a ring-shaped structure 10e , which in Fig. Figure 9 is shown. More precisely, the ring-shaped structure 10e the distance between the majority of through holes 10H gradually from the outer edges towards the center, also in the width direction. For example, in cases where the tire wears down 1As the wear progresses and there is a tendency towards shoulder wear (relatively speaking, shoulder sections wear out first), the thickness of the tread rubber (the rubber layer) is increased. 11 ) uneven in the lateral direction. Therefore, in a cross-section of the ground contact area, the ring-shaped structure may not be able to remain parallel to the central axis (the Y-axis), and this can lead to a decrease in the durability of the tread rubber. Compared to the ring-shaped structure 10 from Fig. 2-2 the bending stiffness of the edge sections (i.e. the shoulder sections of the tire) was 1 ) in the ring-shaped structure 10e lowered. Therefore, compared to the ring-shaped structure, it exhibits 10 from Fig. 2-2 the ring-shaped structure 10e It exhibits a lower bending stiffness and can therefore flexibly adapt to fluctuations in the thickness dimension of the tread rubber (the rubber layer). 11) follow. As a result, a decrease in the durability of the tread rubber can be effectively suppressed. Furthermore, the ring-shaped structure allows for... 10e the through holes 10H The treads should be arranged sparingly in the central section and densely in the shoulder section, so that a penetration ratio (described below) can be maintained and reductions in the durability of the tread rubber caused by variations in thickness dimension can be suppressed.
[0088] The diameter or equivalent diameter of the plurality of through holes 10H varies depending on the position of the through holes 10H in a ring-shaped structure in the lateral direction 10f , which in Fig. Figure 10 is shown. More precisely, the ring-shaped structure 10f the diameter or equivalent diameter of the plurality of through holes 10Hgradually from the outer edges towards the center, also in the direction of width. The ring-shaped structure 10f can the effects of the ring-shaped structure 10e from Fig. 9. Show by the diameter of the through holes 10H and not the density of the through holes 10H is changed. The ring-shaped structure 10f is suitable if a greater adhesion strength is required in the shoulder area than with the ring-shaped structure 10e from Fig. 9 is desired.
[0089] Fig. 11 to Fig. Figure 14 are explanatory drawings for calculating the opening ratio of the through holes. Fig. Figure 15 is a diagram showing the relationship between the opening ratio and the breaking strength ratio. The opening ratio of the through holes is shown below. 10H from the ring-shaped structure 10 described. The in Fig. 2 illustrated ring-shaped structure10 indicates the through holes 10H on and in this case, the cross-sectional area S (calculated by multiplying a distance between adjacent through holes) is used. 10H and 10H with a thickness of the ring-shaped structure 10 A tensile force F is applied. This section is expected to break due to the tensile force F. As in Fig. 12 shown is a unit section 10U through a through hole 10H and the eight through holes 10H , which the through hole 10H surround, defined. The unit section 10U is used to calculate the fracture strength in cases where the ring-shaped structure 10 the through holes 10H does not exhibit, and in cases where the ring-shaped structure 10 the through holes 10H exhibits, used. If the distance between adjacent through holes 10H“b” is a radius of the through holes 10H “r” is the unit section 10U a square area, where 2 × (b + r) = L expresses a length of one side of the square area.
[0090] The relationship between the cross-sectional area ratio of the expected fracture plane and the opening ratio (area ratio in relation to a state in which the through holes 10H (are not provided) in the unit section 10U was sought. It should be noted that it was assumed the breaking force would be proportional to the cross-sectional area S. In each of the unit sections 10U from Fig. 13 and Fig. In section 14, the thickness of the plate was defined as "t". If the through holes 10H are not available ( Fig. 13), the mechanical stress σL of the fracture plane can be expressed by formula (1). If the through holes 10H are available ( Fig. 14), the mechanical stress σB of the fracture plane can be expressed by formula (2). “B” is defined as 2 × b = L – 2 × r = L – 2 × √(α / π). “α” is the opening ratio and is defined as π 2 / L 2 defined. σL = F / (L × t) (1) σB = F / (B × t) (2)
[0091] The breaking force ratio σL / σB is defined as B / L = 1 – 2 × √(α / π). This relationship is in Fig. 15 shown. From Fig. 15 shows that if the opening ratio α exceeds 20%, the breaking force (breaking force ratio) is less than or equal to half, and there is a risk that the performance as a pressure vessel of the ring-shaped structure will be compromised. 10 will not be sufficient. In this case, it is necessary to increase the thickness of the ring-shaped structure. 10 to increase, however, this reduces durability under repeated bending deformation. Therefore, the opening ratio α of the ring-shaped structure10 with the through holes 10H preferably limited to no more than 20%.
[0092] As described above, the pneumatic tire according to this embodiment has an annular structure with a stiffness parameter (defined as the product of the modulus of elasticity and the thickness) that is not less than 10 and not more than 500, and a rubber layer arranged on the outside of the annular structure. Such a structure causes the tire of this embodiment to deform eccentrically, while avoiding local concentrations of stress and strain on the rubber layer in the ground contact area, and thus allowing the load to be distributed in the ground contact area. Consequently, in the tire of this embodiment, local deformation of the rubber layer in the ground contact area is suppressed, and therefore concentrations of stress and strain are distributed in the ground contact area, reducing rolling resistance.Therefore, in this embodiment, a structure can be provided that reduces the rolling resistance of a pneumatic tire. Furthermore, this can be achieved by using a ring-shaped structure with a tensile strength of at least 450 N / m. 2 and no more than 2,500 N / m 2 Sufficient strength and stiffness of the ring-shaped structure are ensured, and the required toughness is guaranteed. Consequently, sufficient compressive strength of the ring-shaped structure can be ensured.
[0093] Since the rubber layer and the annular structure are connected by the through-holes provided in the annular structure, physical bonding is used in addition to chemical bonding to reliably and firmly attach the two components together. As a result, the durability of the pneumatic tire according to this embodiment is improved. Furthermore, due to the structure described above, when the rubber layer of the pneumatic tire according to this embodiment wears down, the rubber layer can be removed from the annular structure and a new rubber layer applied to it. This facilitates retreading. Provided there are no defects, the carcass and the annular structure of the pneumatic tire according to this embodiment can be used several times. Consequently, waste products are reduced and the environmental impact is lowered.Furthermore, in this embodiment of the pneumatic tire, the ring-shaped structure is produced by forming a plate-like element into a cylindrical shape and arranging the ring-shaped structure so that it surrounds the air-filled area. Therefore, in this embodiment of the pneumatic tire, the ring-shaped structure prevents foreign particles from the road contact surface (outer surface of the rubber layer) from penetrating into the air-filled area. Consequently, this embodiment of the pneumatic tire has the advantage of not being susceptible to punctures.
[0094] Products equipped with the same configuration as described in this embodiment provide the same functions and effects as those provided by this embodiment. Furthermore, the configuration of this embodiment can be applied as required, as described below. Second embodiment
[0095] Fig. Figure 16-1 is a perspective view of a ring-shaped structure in the tire according to the second embodiment. Fig. Figure 16-2 is a perspective view of a modification example of the ring-shaped structure in the tire according to the second embodiment. The distribution of the through-holes 10H in a ring-shaped structure 10g this embodiment and a ring-shaped structure 10h One modified example differs in position. In this embodiment, the ring-shaped structure 10g not on the in Fig. The example shown in 16-1 is limited. For example, as in the example in Fig. 16-2 shown ring-shaped structure 10h , depressions and protrusions 10T with a sawtooth shape on both sides in the width direction of the ring-shaped structure 10g be provided. The in Fig. The rubber layer shown in section 4 is located on the outside in the radial direction of the ring-shaped structure. 10g attached, with the recesses and protrusions 10T to serve to strengthen the bond between the ring-shaped structure 10h and the rubber layer 11 to reinforce. Therefore, it is preferable that the ring-shaped structure 10h with the depressions and protrusions 10T is provided because the ring-shaped structure 10h and the rubber layer 11 This allows for more reliable fastening and increases durability. Furthermore, the recesses and protrusions can be used. 10T which extend across both edges in the latitudinal direction of the ring-shaped structure 10h The acting compressive stress is reduced, and therefore a yielding in the circumferential direction of the ground contact area of the tire can occur. 1 This is suppressed. This leads to a longer tire lifespan. 1 The depressions and protrusions10T may have a uniform spacing, however the depressions and protrusions 10T , if uniform harmonics are generated, preferably an uneven spacing.
[0096] Fig. 17 to Fig. Figure 20 are explanatory drawings illustrating the distribution of the through-holes of the annular structure in the tire according to the second embodiment. In the drawings, “W” represents the width direction of the annular structure and “C” the circumferential direction (as in the following examples). In this embodiment, the annular structure 10g at least the opening ratio of the through holes 10H in an area As (groove area), where a groove (main groove Sc in the examples that are in Fig. 17 and Fig. 18 are shown) is provided, lower than that in a region NAs (groove proximity region) near the groove. The in Fig. 17 tires shown 1g is an example with three main grooves (circumferential grooves) Sc, and the one in Fig. 18 tires shown 1g is an example with four main grooves Sc. The one in Fig. 19 tires shown 1g This is an example with four main grooves (circumferential grooves) Sc and a plurality of cleat grooves Sr on both sides in the lateral direction. The one in Fig. 20 tires shown 1g This is an example with four main grooves Sc and a plurality of tread grooves Sr on both sides in the width direction and in a central section. In these examples, the through holes are 10H not in the groove area As of the ring-shaped structure 10g provided, but the through holes 10H NAs are provided in the area near the grooves. Consequently, the opening ratio of the through holes is 10H in the groove area As of the ring-shaped structure 10gsmaller than that in the groove area of NAs.
[0097] Generally, sections of tires with grooves exhibit low bending stiffness. In this embodiment, the ring-shaped structure... 10g the through holes 10H The grooves are not provided or are reduced, or in other words, the opening ratio of the through holes is 10H The flexural stiffness in the groove area As is configured to be smaller than that in the area near the groove NAs. Therefore, the flexural stiffness of the groove area As can be increased to be greater than that in the area near the groove NAs. As a result, inconsistencies in flexural stiffness across the entire tire can be mitigated. 1g This can suppress the fluctuations and improve durability and driving stability. The degree of variation in the opening ratio is preferably set as desired, based on the tire characteristics to be improved.
[0098] If the through holes 10H In the groove area As, rubber, which becomes the tread section, is pressed in by projections of the vulcanizing mold that correspond to the grooves, and as a result, the rubber flows inwards in the tire radial direction of the ring-shaped structure. 10g , which can lead to vulcanization defects. By configuring the opening ratio of the through-holes in this way 10H In the groove area As, which is smaller than in the area near the groove NAs, it can prevent the rubber from moving inwards in the radial direction of the ring-shaped structure. 10g flows.
[0099] Consequently, vulcanization defects can be suppressed, and therefore the quality and yield of the manufactured tire can be improved. 1g can be improved.
[0100] It should be noted that the opening ratio is preferably lower even near the groove area and not only in the groove area As or in the area below the groove (i.e. the projected area of the groove on the annular structure). 10g If the groove is a main groove Sc, the area near the groove region As is a region with a width equal to the sum of the widths of the main groove Sc and a maximum of 15 mm on each side in the lateral direction thereof. If the groove is a lug groove Sr, the area near the groove region As is a region with a width equal to the sum of the widths of the lug groove Sr and a maximum of 10 mm on each side in the lateral direction thereof.
[0101] In the ring-shaped structure 10g a proportion of the total opening area of the through holes 10H relative to an outer surface in the radial direction in a case where the ring-shaped structure 10g the through holes10H does not exhibit, not less than 1% and not more than 30% in an area near a circumferential groove or a main groove Sc (groove-near region NAs), and not less than 0.5% and not more than 15% in an area where the main groove Sc is provided (groove region As). If the groove-near region NAs of the main groove Sc lies within this area, the bond between the ring-shaped structure can 10g and the rubber layer 11 are enhanced, while the effect of improving the bending stiffness of the ring-shaped structure 10 is maintained. As a result, the performance and durability of the tire can be improved. 1g be ensured.
[0102] Fig. 21 and Fig. Figure 22 are top views illustrating a modification example of the ring-shaped structure in the tire according to the second embodiment. Fig. 21 illustrates a ring-shaped structure 10i, which corresponds to a tire with only the main grooves Sc. Fig. 22 illustrates a ring-shaped structure 10j , which corresponds to a tire with both the main grooves Sc and the lug grooves Sr. The spacing of the through holes. 10H in the ring-shaped structures 10i and 10j is the same, however the area of the through holes is 10H In the groove area As, the area is smaller than the area of the through holes. 10H in the area near the grooves NAs. Thus, the opening ratio of the through holes is 10H in the groove area As of the ring-shaped structures 10i and 10j smaller than that in the groove-near region of NAs. With this configuration, the same functions and effects can be achieved as with the ring-shaped structure described above. 10g be provided.
[0103] This embodiment can provide the same functions and effects as those provided by the first embodiment. In this embodiment, the opening ratio of the through-holes in the annular structure is also smaller in at least one area corresponding to the area where the grooves are provided in the tread section of the tire than in an area near the area where the grooves are provided in the tread section. Thus, in the tire according to this embodiment, decreases in flexural stiffness in the sections where the grooves are provided are suppressed, and the performance and durability of the tire can be ensured. Third embodiment
[0104] In the third embodiment, conditions during vulcanization in the manufacture of the pneumatic tire according to the first embodiment or the second embodiment are described. Fig. 23-1 to Fig. Figures 26-2 are schematic diagrams illustrating the conditions during the vulcanization of a tire in a vulcanizing mold. These drawings are used to describe a method for manufacturing the pneumatic tire according to this embodiment. The tire is described below. 1 The first embodiment is used as an example, but the tire according to the second embodiment is the same.
[0105] First, a cylindrical ring-shaped structure is created. 10 (see Fig. 2-1) with a plurality of through holes 10H Provided. Next, unvulcanized rubber is applied radially to an outer surface and / or to an inner surface of the ring-shaped structure. 10arranged and a tire blank is produced. A second rubber 21 , which is arranged on the inside in the tire radial direction, is rubber, which is mainly for the purpose of adhesion to the ring-shaped structure 10 is used. As in Fig. As shown in 23-1, the tire blank is a laminate consisting of a first rubber. 20 (unvulcanized), the second rubber 21 (unvulcanized), the ring-shaped structure 10 , a carcass 22 (unvulcanized) and an inner soul 23 (unvulcanized). During vulcanization, the tire blank is placed in a vulcanizing mold. 25 set. The first rubber 20 and the second rubber 21 After vulcanization, the in Fig. 1 rubber layer shown 11 The first rubber 20 and the second rubber 21 stand above the majority of the through holes 10Hthe ring-shaped structure 10 in contact.
[0106] In this state, the tire blank is formed by applying pressure P to the laminate from the side of the inner core. 23 to the vulcanizing mold 25 It is pressed and heated using a vulcanizing bellows or similar device. Since the elastic modulus of the ring-shaped structure 10 Because the pressure is high, radial swelling due to vulcanization pressure does not easily occur. Therefore, when pressure is applied to the laminate, the pressure is exerted by the vulcanizing bellows or similar device from the inner core side. 23 not easily through the first rubber 20 , which becomes the tread section, and vulcanization defects or the like can occur. In this embodiment, the second rubber 21 on the inside in the tire radial direction of the ring-shaped structure 10 arranged and, as in Fig. As shown in 23-2, the second rubber is forced through due to the pressure from the vulcanizing bellows or the like. 21 through the through holes 10H the ring-shaped structure 10 Furthermore, due to the pressing on the outside in the radial direction of the ring-shaped structure, 10 Pressure on the first rubber 20 , which will become the tread section, is created. Consequently, vulcanization defects and the like can be suppressed, and the quality and yield of the manufactured tire can be improved. 1 can be improved. Furthermore, the second rubber is produced during vulcanization. 21 through the through holes 10H the ring-shaped structure 10 and will be attached to the first rubber 20 bound. Consequently, in the ring-shaped structure 10 the first rubber 20 and the second rubber 21 due to the anchoring effect of the second rubber21 , which through the through holes 10H was guided, be strongly bound. In this process, the second rubber 21 , which is mainly used for the purpose of adhesion, only on one surface of the inside in the tire radial direction of the ring-shaped structure 10 arranged and the vulcanization is carried out in such a way that the ring-shaped structure 10 It is positioned between adhesive rubber layers. In this process, the composition of the second rubber is 21 preferably one that exhibits excellent adhesion to the ring-shaped structure 10 exhibits.
[0107] Fig. 23-1 and Fig. 23-2 illustrate examples where part of the second rubber 21 through the through holes 10H reached and to the side of the first rubber 20 migrates, with the ring-shaped structure forming after vulcanization 10between the first rubber 20 and the second rubber 21 is arranged. Fig. 24-1 and Fig. 24-2 illustrate examples where the entire second rubber 21 through the through holes 10H reached and to the side of the first rubber 20 migrates, with the ring-shaped structure forming after vulcanization 10 between the first rubber 20 and the carcass 22 is arranged. Here the quantity of the second rubber can be determined. 21 , which migrates, can be adjusted by changing the thickness of the second rubber. 21 or the pressure P during vulcanization can be adjusted. As described above, the thickness of the rubber layer between the ring-shaped structure can be adjusted. 10 and the carcass 22 is relatively easy to adjust because of the ring-shaped structure 10 the through holes 10Hexhibits. In this process, the second rubber 21 , which is primarily for the purpose of facilitating adhesion to the ring-shaped structure 10 is used only on one surface of the inside in the tire radial direction of the ring-shaped structure 10 arranged, and the vulcanization is carried out in such a way that the second rubber 21 towards the outside in the radial direction of the ring-shaped structure 10 migrates. In this process, the tire can 1 lighter because of the thickness of the second rubber 21 can be reduced.
[0108] Fig. 25-1 and Fig. 25-2 illustrate an example where the ring-shaped structure 10 before vulcanization in the second rubber 21 is embedded and then vulcanization is carried out. In particular, the second rubber can 21on the inside in the tire radial direction and on the outside in the radial direction of the ring-shaped structure 10 This procedure is suitable if it is to be avoided that the first rubber 20 the outer side in the radial direction of the ring-shaped structure 10 touches and remains there. Furthermore, in this process, the adhesion strength between the ring-shaped structure is... 10 and the second rubber 21 largest. Fig. 26-1 and Fig. 26-2 illustrate an example where the ring-shaped structure 10 in the first rubber 20 is embedded and the carcass 22 on the inside in the tire radial direction of the first rubber 20 is arranged without the second rubber 21 to be used, and then vulcanization is carried out. In particular, vulcanization is carried out after the first layer of rubber has been applied. 20on the outside in the radial direction and on the inside in the radial direction of the ring-shaped structure 10 This process can reduce manufacturing costs because the types of rubber used do not increase. Fourth embodiment
[0109] In the fourth embodiment, a method for producing the ring-shaped structure described above is described. Fig. Figure 27 is a flowchart illustrating the steps of a process for producing the ring-shaped structure in the tire. Fig. 28-1 to Fig. 28-3 are explanatory drawings that illustrate the steps of the process for producing the ring-shaped structure. Fig. Figure 28-4 is a cross-sectional view showing the thickness of a welded section. Fig. Figure 28-4 illustrates a cross-section of the sheet material on a plane perpendicular to a surface of the sheet material. The tire is shown below. 1 and the ring-shaped structure 10 The first embodiment uses examples, but the tire in the second embodiment is the same.
[0110] During the production of the ring-shaped structure 10 will first, as in Fig. 28-1 shown, a plate material 30 , which, when viewed flat, has a rectangular shape and protrusions 32 exhibits, which project outwards in a direction parallel to a transverse direction, on the sides of both edges 30TL and 30TL in the longitudinal direction (that indicated by the arrow “C” in Fig. 28-1 (indicated direction) on both edges 30TS and 30TS in the transverse direction (that indicated by the arrow “S” in Fig. 28-1 indicated direction) trained (step S101, Fig. 28-1). When viewed from the ground, both edges correspond 30TS and 30TS in the transverse direction along the long sides of the rectangular sheet material 30 Furthermore, when viewed from a flat perspective, both edges correspond 30TL and 30TL in the longitudinal direction along the short sides of the rectangular sheet material 30 The sheet material 30 This can be achieved, for example, by cutting a large metal plate element. In this embodiment, the plate material has 30 a plurality of through holes 30H on.
[0111] Then both edges 30TL and 30TL of the sheet material 30 joined together longitudinally adjacent to each other and welded together (step S102, Fig. 28-2). Both edges 30TL and 30TL running in the longitudinal direction preferably perpendicular to the longitudinal direction of the plate material 30(the one marked by arrow “C” in Fig. (in the direction indicated on 28-2). In such a configuration, repeated bending in the welded section can result from repeated deformation of the ring-shaped structure. 10 occurring in the radial direction, a decrease in the durability of the ring-shaped structure 10 This can be suppressed because the length of the welded section where repeated bending occurs can be shortened. Therefore, when using the ring-shaped structure... 10 in the tire 1 A decrease in durability can be suppressed.
[0112] Applicable welding processes include gas welding (oxyacetylene welding), arc welding, TIG welding (tungsten inert gas welding), plasma welding, MIG welding (metal inert gas welding), electroslag welding, electron beam welding, laser beam welding, ultrasonic welding, and the like. Thus, the ring-shaped structure can be...10 They can be easily produced by welding both edges of the sheet material. It should be noted that after the welding process, the sheet material 20 It can be subjected to heat and / or drawing treatment. As a result, the strength of the manufactured ring-shaped structure can be increased. 10 increased. For example, when using precipitation-hardened stainless steel, one example of heat treatment is a treatment in which the plate material 20 It is heated for 60 minutes at 500°C. However, there are no restrictions regarding the heat treatment conditions, and these can be modified as needed to achieve the desired properties.
[0113] Then, after welding, the protrusions are... 32 removed and the in Fig. 2-1 illustrated ring-shaped structure 10 is achieved (Step S103, Fig. 28-3). The heat treatment and the like of the ring-shaped structure 10 is preferably carried out after the protrusions 32 of the welded cylindrical plate material 30 were cut off. Since the strength of the welded cylindrical plate material 30 (ring-shaped structure) 10 ) due to heat treatment or the like, the protrusions may be increased 32 They can be cut off more easily before heat treatment or similar processes. After achieving the ring-shaped structure. 10 the rubber layer 11 and the carcass section 12 , shown in Fig. 3, to the ring-shaped structure 10 attached and the bead sections 13 are in the carcass section 12 provided. Thus, a tire blank is produced (step S104). Subsequently, the tire blank is vulcanized (step S105) and the in Fig. 1 tire shown 1 is complete. It should be noted that the process for manufacturing the ring-shaped structure 10 is not limited to the example described above. For example, the ring-shaped structure 10 produced by cutting a cylinder, or the ring-shaped structure 10 Alternatively, it can be manufactured using an injection molding process.
[0114] The ring-shaped structure 10 has a welded section 10W as in Fig. 28-3 shown on. As in Fig. As shown in 28-4, the welded section 10W a thickness greater than the thickness of its surrounding areas. A thickness t in an area of the welded section. 10W , except for the welded section 10WThe thickness itself is not less than 0.1 mm and not more than 0.8 mm, and preferably not less than 0.15 mm and not more than 0.7 mm. Furthermore, the thickness of the welded section is 10W , which is greater than the thickness of its surrounding areas, not more than 1.3 times and preferably not more than 1.2 times the thickness of the surrounding areas. If the values are within this range, resistance to repeated bending can be ensured while simultaneously guaranteeing compressive strength. The area "except at the welded section" 10W “self” refers to the thickness of the sheet material. 20 before welding and refers to the ring-shaped structure 10 on areas other than the welded section 10W , which have a uniform thickness.
[0115] In this embodiment, after the plate material has been welded together... 30 preferably the welded cylindrical plate material 30 subjected to heat treatment and / or the welded cylindrical plate material 30 The cylinder is subjected to a drawing process in the axial direction. This treatment allows the material properties of the welded section (metallographic structure), which were altered by the welding process, to be adjusted to resemble those of the unwelded section, thereby increasing the fracture toughness of the welded section. It should be noted that during the execution of the aforementioned procedures, a number of ring-shaped structures are formed. 10This can be produced simultaneously by: producing a long, cylindrical material by welding a sheet material with a large width dimension; subjecting the resulting cylinder to the treatments described above; and subsequently cutting the cylinder perpendicular to an axis of the same at the annular structure width Wm (belt width). Reference symbol list 1, 1a, 1b, 1c, 101, 101a Pneumatic tires (tires) 2 Structure 2S Both sides 10, 10a, 110, 110a ring-shaped structure 10so, 110so, 110soa outside 10si inside 10T depressions and protrusions 11, 111, 111a Rubber layer 11so, 111so, 111so outside 11si inside 12, 12a, 12b, 12c carcass section 12F fiber 12R rubber 13 Tire bead section 13h Heel section 14 Inner Soul Main groove (circumferential groove) Sr Stollenrille QUOTES INCLUDED IN THE DESCRIPTION
[0116] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited non-patent literature
[0117] Recent Technical Trends in Tires, Akimasa DOI, Journal of the Society of Rubber Industry, Sep. 1998, Vol. 71, pp. 588–594
[0003] JIS G4303
[0064]
Claims
[1] pneumatic tire comprising a cylindrical annular structure having a plurality of through holes, a rubber layer which becomes a tread portion provided along a circumferential direction of the annular structure on an outer side of the annular structure, and a carcass portion which has fibers covered with rubber and which is present at least on both sides in a direction parallel to a central axis of the cylindrical structure having the annular structure and the rubber layer. [2] pneumatic tires comprising a cylindrical annular structure having a plurality of through holes, a rubber layer, which becomes a tread portion, provided along a circumferential direction of the ring-shaped structure on an outer side of the ring-shaped structure, a groove provided on an outer side in a radial direction of the rubber layer, and a carcass portion which has fibers covered with rubber and which is present at least on both sides in a direction parallel to a central axis of the cylindrical structure having the annular structure and the rubber layer, wherein an opening ratio of the through holes in at least a region where the groove is provided is smaller than an area near the area where the groove is provided. [3] The pneumatic tire according to claim 2, wherein a proportion of a total of the opening area of the through holes relative to a surface of the outside in a radial direction in a case where the annular structure does not have the through holes is not less than 1% and not more than 30%. in an area near a circumferential groove, and not less than 0.5% and not more than 15% in an area where the circumferential groove is provided. [4] The pneumatic tire according to any one of claims 1 to 3, wherein a cross-sectional area of one of the through holes is not less than 0.1 mm 2 and no more than 100 mm 2 amounts to. [5] The pneumatic tire according to any one of claims 1 to 4, wherein a sum of the area of the through holes is not less than 0.5% and not more than 30% of the surface area of the outside in the radial direction of the annular structure. [6] The pneumatic tire according to any one of claims 1 to 5, wherein the outside of the rubber layer and the outside of the annular structure except for a groove portion of the rubber layer are parallel to the central axis. [7] The pneumatic tire according to any one of claims 1 to 6, wherein the annular structure is attached further outward in the radial direction of the structure than the carcass portion. [8] The pneumatic tire according to any one of claims 1 to 7, wherein the annular structure is a metal. The pneumatic tire according to any one of claims 1 to 8, wherein a dimension in the central axis parallel direction of the annular structure is preferably at least 50% and at most 95% of the total width in the central axis parallel direction of the pneumatic tire. [10] A method of manufacturing a pneumatic tire, wherein the pneumatic tire has a rubber layer which becomes a tread portion and which is provided on an outside of a cylindrical annular structure, the method comprising the steps of: Obtaining a cylindrical ring-shaped structure having a plurality of through holes, and wherein an opening ratio of the through holes in an area of the tread portion where a groove is provided is smaller than that in an area near the area where the groove is provided ; preparing a green tire by disposing unvulcanized rubber on a radially outer side and a radially inner side of the annular structure, respectively, and passing the rubber on the inside in the radial direction of the annular structure through the through holes to the outside in the radial direction by applying pressure and heat to the green tire from the inside in the radial direction of the tire after setting the green tire in a vulcanizing mold.