JP2006240528A - Tire wheel assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber-like elastic body with excellent aging-proof adhesion property in a run flat tire wheel assembly having a run flat support formed from an annular metal shell and the rubber-like elastic body. <P>SOLUTION: In the run flat tire wheel assembly having the run flat support formed by the annular metal shell and the rubber-like elastic body in an inner cavity of a tire/rim, the rubber-like elastic body is constituted by a rubber composition containing 100 pts.wt. of diene-based rubber and 0.1-10 pts.wt. of nickel-coating graphite. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tire wheel assembly used for a pneumatic tire (hereinafter referred to as a run-flat tire) capable of limited operation in a damaged or deflated state, and more specifically, a tire wheel assembly excellent in anti-aging adhesion. About.

  There is a need for a run-flat tire that has the possibility of emergency driving that can travel a certain distance even when the internal pressure of a pneumatic tire drops suddenly due to puncture or burst while driving a car etc. Proposals have been made. As such a proposal, for example, in Patent Documents 1 and 2, a run-flat support body (core body) is mounted on the rim of the inner cavity portion of the pneumatic tire, thereby supporting the punctured pneumatic tire. Thus, a technology that enables run-flat running has been proposed.

  In Patent Document 3, in order to bond steel and rubber, an indirect adhesive is usually used or a special surface treatment is applied, but the rubber compound side is made of a high sulfur compound / resin compound system. As a result, a technique that enables direct bonding of steel and rubber has been proposed. After that, in order to directly bond steel and rubber, researches such as acetylacetonate compounding, silica compounding, and iron naphthenate use have been conducted. In view of the aging resistance, a method in which a directly-adhesive rubber and a general-purpose rubber are arranged in a two-layer structure and molded has been studied.

JP-A-10-297226 JP-T-2001-519279 JP 2004-106692 A

  An object of the present invention is to provide a rubber-like elastic body excellent in anti-aging adhesion in a run-flat tire wheel assembly having a run-flat support body formed from an annular metal shell and a rubber-like elastic body. .

  According to the present invention, in the run-flat tire wheel assembly having a run-flat support body formed of an annular metal shell and a rubber-like elastic body in the inner cavity of the tire / rim, the rubber-like elastic body is a gen system. Provided is a tire / wheel assembly having improved anti-aging adhesion between an annular metal shell and a rubber-like elastic body by comprising a rubber composition containing 100 parts by weight of rubber and 0.1 to 10 parts by weight of nickel-coated graphite. .

  According to the present invention, a rubber-like elastic body excellent in anti-aging adhesion can be obtained by using an adhesive compound containing modified graphite coated with nickel on the graphite surface for a rubber-like elastic body of a core type run-flat tire. Obtainable.

  In order to improve the anti-aging adhesion of a run-flat tire wheel assembly having a run-flat support body formed by an annular metal shell and a rubber-like elastic body in the inner cavity of the tire / rim. As a result of intensive studies, the rubbery elastic body is composed of a rubber composition containing 100 parts by weight of Gen-based rubber and 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight of nickel-coated graphite. The present inventors have found that the anti-aging adhesion between the annular metal shell and the rubber-like elastic body is improved, and have led to the present invention.

  According to a preferred embodiment of the present invention, the weight ratio of carbon black / silica as a reinforcing filler is preferably 10/1 to 1/2, more preferably 5/1 to 100 parts by weight of diene rubber. Silane coupling in a proportion of 1/1, preferably 40-90 parts by weight, more preferably 50-80 parts by weight, and preferably 1-20% by weight, more preferably 5-10% by weight, based on the weight of silica. By blending the agent, a preferable rubber-like elastic body excellent in anti-aging adhesion can be obtained.

Hereinafter, the present invention will be specifically described with reference to embodiments shown in the drawings.
1, 2 and 3 are meridian cross-sectional views showing the main parts of a typical embodiment of a tire wheel assembly (wheel) of the present invention.

  For example, as shown in FIGS. 1, 2 and 3, a run-flat support 1 according to the present invention includes an annular metal shell 4, 5 or 6 inserted into a cavity 3 of a pneumatic tire 2 and a rubber-like member. The elastic body 7 is formed. The run-flat support 1 has a shape smaller than the inner diameter of the cavity 3 so that the outer diameter is kept at a constant distance from the inner surface of the cavity 3 of the pneumatic tire 2, and the inner diameter is a bead of the pneumatic tire. The dimension is substantially the same as the inner diameter of the part. The run-flat support 1 is inserted into the rim 8 of the wheel together with the pneumatic tire 2 in a state of being inserted inside the pneumatic tire 2 to constitute a tire wheel assembly. When this tire-wheel assembly is mounted on an automobile or the like and the pneumatic tire is punctured while running, the punctured and crushed tire 2 is supported on the outer peripheral surface of the run-flat support body 1, Run-flat driving is possible.

  As described above, the run-flat support body of the tire wheel assembly of the present invention is composed of the annular metal shell and the rubber-like elastic body, and the annular metal shell 4, 5 or 6 is punctured outside. A continuous support surface is formed to support the tire, and the inside has a shape with left and right side walls as legs. The outer support surface can take various shapes, for example, a flat one as shown in FIG. 1 or a cross section perpendicular to the circumferential direction as shown in FIG. (The number of convex curved surfaces arranged in the tire axial direction may be two as shown in FIG. 2, or three or more, or even a single one), and as shown in FIG. It is composed of the above convex curved surface, and an elastic ring 9 having a circular cross section is provided in the concave portion to give impact mitigation ability during run flat running and / or the annular metal shell is separated by a rubber elastic body Thus, the side wall of the metal shell can be in direct contact with the rim so that a stable engagement state can be maintained. Even when the support surface is formed in this way, the run-flat running distance of the tire can be extended if the adhesion between the metal and the rubber-like elastic body is increased according to the present invention.

  The rubber-like elastic body is attached to the ends (see FIG. 1 or FIG. 2) of the legs of the annular metal shell or in the legs (see FIG. 3), respectively, and comes into contact with the left and right rims as it is. Support. This rubber-like elastic body is composed of the rubber composition according to the present invention, and alleviates the impact and vibration received by the annular metal shell from a punctured tire and the like, and acts as an anti-slip against the rim. Stable support on top.

As shown in FIG. 4, the annular metal shell 5 and the rubber-like elastic body 7 constituting the run-flat support body 1 have a strong adhesive force, but it is preferable to secure a predetermined adhesion area. The load during rim work and run flat running is made dimensionless by the rim diameter R (inch), and when the bonding area is S (cm ² ), the ratio S / R is 4.5 cm ² / inch or more. Preferably it is 8-20 cm < ² > / inch. Here, the adhesion area is the adhesion area between the metal and the rubber-like elastic body at one end of the annular metal shell, that is, the metal in contact with the rubber-like elastic body at the end of the annular metal shell in the cross section orthogonal to the circumferential direction. It means the total adhesion area in which the front / back surface and end surface of the shell make a round in the circumferential direction.

  Furthermore, the bonding surface between the annular metal shell 5 and the rubber-like elastic body 7 is preferably constituted by an axial direction and a radial direction, and it is more preferable that both are substantially equal. As a result, a structure that can withstand both axial and radial forces generated during run-flat travel is formed.

  1, 2, and 3, the run-flat support body 1, the pneumatic tire 2, and the rim 8 are formed in an annular shape coaxially with a wheel rotation axis (not shown) as a center. There are no particular limitations on the dimensions of the metal shell, but the thickness is preferably 0.5 to 3.0 mm, and the width is substantially equal to the distance between the left and right tire bead toes.

  In the tire wheel assembly of the present invention, the annular metal shell 4, 5 or 6 is made of a metal material so as to support the weight of an automobile or the like via a punctured tire. Examples of such metals include iron, stainless steel, and aluminum alloys.

  In the present invention, the rubber-like elastic body stably supports the cyclic metal shell and improves the adhesion with the cyclic metal shell, particularly the anti-aging adhesion. As described above, the nickel-coated graphite is blended with the diene rubber. It can comprise from the rubber composition. Examples of the diene rubber used in the present invention include natural rubber, polyisoprene rubber, styrene-butadiene copolymer rubber, and polybutadiene rubber.

  In the present invention, in order to improve the aging-resistant adhesion between the annular metal shell of the run-flat support and the rubber-like elastic body, the rubber-like elastic body is coated with nickel-coated graphite 0.1% with respect to 100 parts by weight of the diene rubber. It is comprised from the rubber composition containing 10 weight part. If the amount of nickel-coated graphite is too small, sufficient adhesion between the metal shell and the rubber-like elastic body cannot be obtained, which may cause failure during run-flat running. As a result, the run-flat running performance is lowered, which is not preferable.

  The nickel-coated graphite used in the present invention can be obtained, for example, as described in US Pat. No. 5,876,793. That is, it is produced by circulating graphite in a CVD (chemical vapor deposition) reactor and coating it with nickel. In this way, nickel particles are deposited on the surface of graphite by CVD, so that nickel and graphite are firmly bonded to some extent. Such nickel-coated graphite is, for example, POWDERMET. Commercial products such as “Nickel coated Graphite powder” manufactured by INC Company may also be used.

  The rubber composition according to the present invention includes tires such as other reinforcing agents (fillers), vulcanization or cross-linking agents, vulcanization or cross-linking accelerators, various oils, anti-aging agents, and plasticizers in addition to the components described above. Various additives that are generally blended for general rubber can be blended, and these additives are kneaded by a general method to form a composition and used for vulcanization or crosslinking. Can do. The blending amount of these additives can be a conventional general blending amount as long as the object of the present invention is not violated.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, it cannot be overemphasized that the scope of the present invention is not limited to these Examples.

Examples 1-3 and Comparative Examples 1-2
The effect of the present invention will be demonstrated using a rubber-like elastic body composed of a rubber composition having a composition (parts by weight) shown in Table I.

  Next, a rubber-like elastic sample (size: 5.5 mm thickness × 2.5 cm width × 8 cm length) having the composition (parts by weight) shown in Table I was prepared (except for sulfur and vulcanization accelerators, first using a Banbury mixer). The mixture was mixed until the temperature reached 150 ° C., and then sulfur and a vulcanization accelerator were added and mixed at 80 ° C. for 3 minutes. A substrate (made of iron) was heated and adhered to this at 150 ° C. for 60 minutes. The results are shown in Table I.

Physical property evaluation test method Peeling force: Measured for each sample before and after thermal aging according to JIS K6256 vulcanized rubber and thermoplastic rubber adhesion test method, and the value of Comparative Example 1 is shown as an index. did. The larger this value, the better the adhesion. Thermal aging was performed in a gear oven under conditions of 80 ° C. × 96 hours.
Retention rate after heat aging: For each sample, the peel force after heat aging was expressed as an index, with the peel force before heat aging being 100. It shows that there is little adhesive force fall by heat, so that this figure is large.

Run-flat durability test: tire wheel assembly according to the present invention (Examples 1 and 2) and tire wheel assembly according to Comparative Examples 1 to 3 with a tire size of 205 / 55R16 89V and a rim size of 16 × 6 1 / 2JJ And were produced respectively. This test tire was mounted on a 2500 cc passenger car, the tire pressure on the right front tire was 0 KPa, the tire pressure on the other three tires was 200 KPa, and the vehicle was run at 90 km / hr until failure. The result was expressed as an index with the value of Comparative Example 1 as 100. The larger this value, the better the durability.

NR: RSS # 3
CB: SHOBLACK N326M: Showa Cabot Co., Ltd., N ₂ SA: 82 m ² / g, DBP oil absorption: 72 ml / 100 g
ZnO: Zinc oxide 3 types: 6 PPD manufactured by Shodo Chemical Industry Co., Ltd .: SANTOFLEX 6PPD: FLEXSYS manufactured stearic acid: Alfa phenol resin manufactured by Nippon Oil & Fats Co., Ltd .: Hitachi Chemical 2501Y
Sulfur: Sanshin Chemical Industry Co., Ltd. Cobalt Naphthenate: Dainippon Ink Chemical Industries, Ltd. Nickel Naphthenate: Dainippon Ink Chemical Industries, Ltd. Nickel Coating Graphite: POWDERMET INC. Made (Ni content 40%)

  As described above, conventionally, it is very difficult to bond a rubber-like elastic body with a metal such as iron or stainless steel, which has poor adhesion to rubber alone, and even if it can be bonded, the strength is insufficient. In many cases, the durability over time was poor. According to the present invention, a rubber-like elastic body was obtained from a rubber composition in which 0.1 to 10 parts by weight of nickel-coated graphite was blended with 100 parts by weight of diene rubber. By configuring the structure, the anti-aging adhesion between the annular metal shell and the rubber-like elastic body is improved, and the durability as a run-flat support body is greatly improved.

It is meridian sectional drawing which shows the principal part of one embodiment of the tire wheel assembly of this invention. It is meridian sectional drawing which shows the principal part of the other embodiment of the tire wheel assembly of this invention. It is meridian sectional drawing which shows the principal part of the further another embodiment of the tire wheel assembly of this invention. It is drawing which shows an example of the adhesion surface of the cyclic | annular metal shell and rubber-like elastic body of the tire wheel assembly of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support body for run flats 2 Pneumatic tire 3 Cavity part 4 Annular metal shell 5 Annular metal shell 6 Annular metal shell 7 Rubber-like elastic body 8 Rim 9 Elastic ring

Claims (6)

  In a run-flat tire wheel assembly having a run-flat support body formed of an annular metal shell and a rubber-like elastic body in an inner cavity of a tire / rim, the rubber-like elastic body is made of 100 parts by weight of Gen rubber and nickel. A tire wheel assembly having improved anti-aging adhesion between a cyclic metal shell and a rubber-like elastic body by comprising a rubber composition containing 0.1 to 10 parts by weight of coated graphite.   The rubber elastic body comprises 100 parts by weight of a diene rubber, 40 to 90 parts by weight of carbon black / silica as a reinforcing filler in a ratio of 10/1 to 1/2 (weight ratio), and 1 part by weight of the silica. The tire-wheel assembly according to claim 1, comprising -20% by weight of a silane coupling agent.   The tire-wheel assembly according to claim 1 or 2, wherein a rubber-like elastic body of the run-flat support body is disposed between the annular metal shell and the rim to support the annular metal shell.   The tire wheel assembly according to any one of claims 1 to 3, wherein a material of the annular metal shell is steel or stainless steel. The ratio S / R is 4.5 cm ² / inch or more, where R is the nominal diameter of the tire and S (cm ² ) is the rubber-like elastic body / metal bonding area. The tire wheel assembly according to any one of the above.   The tire wheel assembly according to any one of claims 1 to 5, wherein the bonding surface is constituted by a substantially axial direction surface and a substantially radial direction surface.

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