KR20050042474A - Tire wheel assembly for run-flat tire - Google Patents

Abstract

A tire wheel assembly where the inner cavity section of tire/rim is provided therein with a core for run-flat arranged so that a thin and rigid annular shell is supported on a rim by a resilient ring. A tire wheel assembly of run-flat, especially a tire wheel assembly of run-flat where the resilient ring constituting the core can be recycled, is obtained by composing the resilient ring of a thermoplastic elastomer composition having such a structure that a rubber composition (B) is dispersed into thermoplastic resin (A), or of a composition of hydrogen bonding thermoplastic elastomer comprising an elastomer polymer having a carbonyl group containing group and a heterocyclic amine containing group in the side chain and/or the thermoplastic elastomer.

Description

Tire wheel assembly for run-flat tires

The present invention relates to a tire wheel assembly for use in pneumatic tires (hereinafter referred to as run flat tires) capable of limited driving in a damaged or deflated state, and more particularly to tires / rims. A tire wheel assembly capable of recycling a run-flat heavy body composed of a highly rigid annular shell and an elastic ring installed in an inner cavity of the engine.

There is a demand for run-flat tires with the possibility of emergency driving that can travel a certain distance even when the pneumatic tire is suddenly lowered due to puncture or rupture while driving a car. It is done. For example, Japanese Patent Laid-Open No. 10-297226 or Japanese Laid-Open Patent Publication No. 2001-519279 discloses a support for running flats on the rim of the inner cavity of a pneumatic tire (hereinafter, referred to as "Medium"). And a flat tire that supports flat tires, thereby enabling run-flat driving. In addition, Japanese Laid-Open Patent Publication No. 2001-163020 and Japanese Laid-Open Patent Publication No. 1998-297226 also confirm the disclosure regarding run flat tires.

The run flat core body has an annular member having the outer circumferential side as a support surface, attaches an elastic ring to its embossed portion, and takes the structure in which the core body is supported on the rim of the tire through the elastic ring. have. In addition, the technology using the heavy runner body can be used as it is without any special design change to the wheel / rim of a conventional general pneumatic tire, so that the manufacture, processing and installation of a conventional pneumatic tire It has the advantage that the equipment can be used as it is.

However, in recent years, tire recycling has become important in the tire industry in view of resource saving and environmental conservation. In view of the recyclability of the run flat tire in this respect, it has been found that it is necessary to make the run flat heavyweight body, in particular, an elastic ring that is a component thereof.

Disclosure of the Invention

Therefore, the present invention is a tire wheel in which the elastic ring constituting the run flat core body of the run flat tire wheel assembly is improved in the run flat core body so that the elastic ring after use can be recycled while ensuring durability of the run flat. It is an object to provide an assembly.

According to the present invention, in a tire wheel assembly provided with a run-flat heavyweight body in which a thin-walled rigid annular shell is supported on a rim by an elastic ring, an elastic ring is a thermoplastic resin. There is provided a tire wheel assembly composed of a thermoplastic elastomer composition having a structure in which a rubber composition (B) is dispersed in (A).

According to the present invention, in a tire wheel assembly equipped with a run-flat heavyweight body in which a thin, rigid annular shell is supported on the rim by an elastic ring at an inner cavity of the tire / rim, the elastic ring is formed of a carbonyl group-containing group; There is also provided a tire wheel assembly composed of a hydrogen bondable thermoplastic elastomer composed of an elastomeric polymer having a heterocyclic amine containing group in the side chain and / or the thermoplastic elastomer composition.

Hereinafter, the present invention will be described with reference to the drawings.

1 is a meridian cross-sectional view showing the main portion of an example of a tire wheel assembly of the present invention.

MEANS TO SOLVE THE PROBLEM The present inventors conducted the research in the run flat middle body formed from the highly rigid annular shell and an elastic ring for the purpose of making it possible to recycle the elastic ring after use, ensuring the durability of a run flash. It has been found that the above object can be achieved by using the elastic ring as a thermoplastic elastomer composition or a hydrogen bond thermoplastic elastomer in which a rubber composition is dispersed in a thermoplastic resin. In addition, in order to secure the adhesion between the elastic ring and the rigid annular shell made of such a material, the contact area or the shape of the shell portion of the annular shell and the elastic ring can be devised to allow recycling, and at the same time, more desirable durability can be obtained. Found out.

EMBODIMENT OF THE INVENTION Hereinafter, it demonstrates more concretely below, referring an example of the tire wheel assembly of this invention shown in FIG. 1 is a meridian cross-sectional view showing the main parts of a representative example of a tire wheel assembly (wheel) of the present invention.

The run flat core body 1 according to the present invention is, for example, a highly rigid annular shell 4 inserted into the inner cavity 3 of the tire / rim of the pneumatic tire 2, as shown in FIG. 1. ) And an elastic ring (5). The run flat core body 1 has a shape smaller than the inner diameter of the inner cavity 3 so that the outer diameter is maintained at a constant distance from the inner surface of the inner cavity 3 of the pneumatic tire 2, and the inner diameter thereof is further reduced. The diameter is generally formed in the same dimension as the inner diameter of the bead portion of the pneumatic tire. The runflat core body 1 is incorporated into the rim 6 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 such a tire wheel assembly is mounted on an automobile or the like and the pneumatic tire is flat while driving, the flat tire or the crushed tire 2 is supported on the outer circumferential surface of the run flat core body 1, thereby allowing run flat driving.

As described above, the run flat core body of the tire wheel assembly of the present invention is an annular shell (4) made of a high rigid material (for example, metal materials such as iron, stainless steel, steel, aluminum alloy, or fiber reinforced synthetic resin). ) And the elastic ring 5, the annular shell 4 forms a continuous support surface in order to support a flat tire on the outside, and the inside has the shape which made the left and right side wall the corner part. The outer support surface may take various shapes, for example, a shape in which a cross-sectional shape orthogonal to its main direction becomes a convex curved surface on the outside as shown in FIG. 1 (convex curved tire) The number parallel to the axial direction is not limited to two, as shown in FIG. 1, and may be three or more or a single one) or a non-flat shape.

The elastic ring 5 is attached, for example, to the distal end of each of the annular shells 4, and supports the annular shell 4 by abutting on the left and right rims 6 as they are. Such an elastic ring 5 is usually made of rubber, to alleviate the shock and vibration received by the annular shell 4 from the flat tire, and to act as a bump against the rim 6 to thereby form the annular shell 4. It acts to stably support on the rim (6).

In order to increase the adhesive force of the highly rigid annular shell 4 and the elastic ring 5 which comprise the run flat core body 1, it is preferable to secure a predetermined | prescribed adhesive area. The load during rim work or run flat running is dimensioned by the nominal internal diameter (R) (inch) of the tire, and its ratio (S / R) is 4.5 cm 2 when the adhesion area is S (cm 2). It is preferable that it is / inch or more, and it is more preferable that it is 8-20 cm <2> / inch. Here, the adhesive area means that of the shell in contact with the elastic ring 5 of the end portion of the annular shell 4 in the cross section orthogonal to the bonding area of the rigid material and the elastic ring at one end portion of the annular shell. It refers to the whole adhesive area which circumscribed the surface / back surface and the end surface in the circumferential direction.

Moreover, it is preferable that the adhesive surface of the annular shell 4 and the elastic ring 5 is comprised by the axial direction and the radial direction, and it is still more preferable if both are substantially equal. This forms a structure that can withstand both the axial and radial forces generated during run flat travel. In FIG. 1, the run flat core body 1, the pneumatic tire 2, and the rim 6 are annularly formed coaxially about the rotation axis (not shown) of a wheel. In addition, although there is no limitation in particular in the dimension of an annular shell, It is preferable to make width approximately the same as the space | interval of right and left tire bead toe at thickness 0.5-3.0mm.

The elastic ring preferably has a 100% modulus (100 ° C.) of at least 1 MPa or more, preferably 1 to 10 MPa, more preferably 2 to 5 MPa, in order to maintain the load bearing capability during run flat running. As a material having recyclability and satisfying the above physical properties, (1) a composite material in which fine rubber particles are dispersed in a resin matrix is preferable, and such a composite material is melted and reused because it softens at the melting point of the matrix resin. Due to the presence of an appropriate elasticity even at high temperatures. (2) A hydrogen bondable thermoplastic elastomer, that is, a thermally reversible crosslinked rubber, is also preferable because it can be melted and reused at a temperature higher than the melting point, and has an appropriate elasticity even at a high temperature of run flat travel. In addition, a material having the physical properties under the above high temperature, having a melting point of at least 120 ° C, preferably 150 ° C, more preferably 180 ° C or more, and having a rubber-like elasticity at 100 ° C or less can be used.

The thermoplastic elastomer composition which can be used for forming the elastic ring according to the present invention is preferably a thermoplastic resin (A) having a melting point of 150 ° C. or higher, preferably a polyamide resin, a polyester resin or a polynitrile resin as a matrix resin. In the at least one thermoplastic resin (A) selected from polyolefin resin, polyvinyl resin, polyphenylene oxide resin and polyimide resin, the rubber composition (B) is preferably (A) / (B) (weight ratio) of 80 / 20 to 25/75, more preferably at a ratio of 70/30 to 35/65, if the ratio of the thermoplastic resin (A) is too large, the rigidity of the elastic ring is increased, the rim assembly is difficult to On the contrary, when too small, rubber | gum becomes difficult to disperse | distribute and it is not preferable because kneading | mixing becomes impossible.

As the rubber of the rubber composition (B), for example, natural rubber, epoxidized natural rubber, diene rubber [e.g. polyisoprene rubber (IR), polybutadiene rubber (BR), conjugated diene-aromatic vinyl copolymer ( Examples: SBR), ethylenically unsaturated nitrile-conjugated diene copolymers (e.g. NBR)] and their hydrogenated additives, olefinic rubbers [ethylene-propylene rubber (EPDM or EPM), maleic acid modified ethylene-propylene rubber (M-EPM) ), Butyl rubber (IIR), isobutylene and aromatic vinyl or diene monomer copolymer)], acrylic rubber (ACM), ionomer, halogen-containing rubber [e.g. CIIR, BIIR, isobutylene-p-methylstyrene Brominated (Br-IPMS), chloroprene rubber (CR), hydrin rubber (CHR, CHC), chlorosulfonated polyethylene (CSM), chlorinated polyethylene (CM), maleic acid modified chlorinated polyethylene (M-CM) ], Sulfur-containing rubbers (e.g. polysulfide rubbers), fluorine rubbers (e.g. vinylidene fluorides) A non-fluorine-containing vinyl ether-based rubber, tetrafluoroethylene-propylene-based rubber and the like, fluorine-containing phosphazene-based rubber), which are preferably be mixed to a single kind or two or more kinds. General purpose additives, such as fillers, such as carbon black, a silica, a calcium carbonate, and a clay, an antioxidant, an oil or a plasticizer, a vulcanizing agent, a vulcanization accelerator, a vulcanization aid, can be mix | blended suitably here.

According to the present invention, as a method of dispersing the rubber composition (B) in the thermoplastic resin (A), for example, the thermoplastic resin (A) and the rubber composition (B) (unvulcanized substance) are previously melted by a twin screw kneading extruder or the like. By kneading, the rubber composition (B) can be dispersed in the thermoplastic resin (A) forming the continuous phase. When vulcanizing the rubber composition (B), a vulcanizing agent may be added during kneading the thermoplastic resin (A) and the rubber composition (B) to vulcanize the rubber dynamically. In addition, although various compounding agents (except a vulcanizing agent) with respect to a thermoplastic resin or a rubber composition may be added during the said kneading | mixing, it is preferable to mix beforehand before kneading | mixing. It does not specifically limit as a kneader used for kneading a thermoplastic resin (A) and a rubber composition (B), A screw extruder, a stirrer, a Banbury mixer, a twin screw kneading extruder, etc. are mentioned. Among these, it is preferable to use the twin screw kneading extruder for kneading the resin component and the rubber composition component and dynamic vulcanization of the rubber composition. Moreover, you may knead sequentially using two or more types of kneaders. As conditions for melt-kneading, it is good if temperature is more than the temperature which a thermoplastic resin melts. In addition, it is preferable that the shear rate at the time of kneading is 2500-7500Sec- ¹ . The total kneading time is 30 seconds to 10 minutes, and when a vulcanizing agent is added, the vulcanization time after addition is preferably 15 seconds to 5 minutes.

On the other hand, the hydrogen-bonding thermoplastic elastomer constituting the elastic ring according to the present invention and the composition comprising the same to form a thermoreversible crosslinked rubber that softens at a constant temperature but restores the rubber-like elasticity at room temperature, specifically, Hydrogen-bonding thermoplastic elastomers composed of elastomeric polymers having carbonyl group-containing groups and heterocyclic amine-containing groups in the side chain (also including molecular ends) and / or suitable formulations therefor, such as carbon black , Fillers such as silica, calcium carbonate and clay, general purpose additives such as anti-aging agents, oils or plasticizers, vulcanizing agents, vulcanization accelerators, vulcanization aids) and the like, and more specifically, for example, For example, it is as described in Unexamined-Japanese-Patent No. 2000-169527. The carbonyl group-containing group may include at least one kind of amide, ester, imide and carboxyl, and specific examples of the group having this and the heterocyclic amine-containing group include the following groups (1) to (5) ).

Specific examples of the elastomeric polymer used in the present invention include diene rubbers such as natural rubber, isoprene rubber, butadiene rubber, 1,2-butadiene rubber, styrene-butadiene rubber, nitrile rubber, and chloroprene rubber. Olefin rubbers such as butyl rubber, ethylene-propylene rubber (EPDM, EPM), chlorosulfonated polyethylene, acrylic rubber, fluorine rubber, epichlorohydrin rubber, polysulfide rubber, silicone rubber, urethane rubber, and the like. . A thermoplastic elastomer (TPE) containing a resin component may be sufficient, for example, water may be added. Polystyrene TPE (SBS, SIS, SEBS), polyolefin TPE, polyvinyl chloride TPE, polyurethane TPE, polyester TPE, polyamide TPE and the like may be used.

The elastomeric polymer may be either liquid or solid. In addition, the molecular weight thereof is not particularly limited and may be appropriately selected depending on the intended use, the crosslinking density and the like.

The carbonyl group-containing group bonded to the side chain of the elastomeric polymer of the present invention is hydrogen bond, and specifically, carbonyl group, carboxyl group (OH), amide group, ester group, imide group and the like can be given. As a compound which can introduce | transduce such a group, a carboxylic acid and its derivative (s) are not specifically limited. As a carboxylic acid compound, the organic acid which has a saturated or unsaturated hydrocarbon group is mentioned, Any of aliphatic, alicyclic, and aromatic carboxylic acid may be sufficient as a hydrocarbon group. Examples of the carboxylic acid derivatives include carboxylic acid anhydrides, esters, ketones, amino acids, amides, imides, and thiocarboxylic acids (mercapto group-containing carboxylic acids). Specifically, it contains carboxylic acids and substituents such as malonic acid, maleic acid, succinic acid, glutaric acid, phthalic acid, isophthalic acid, terephthalic acid, p-phenylenediacetic acid, p-hydroxybenzoic acid, p-aminobenzoic acid and mercaptoacetic acid. Aliphatics such as carboxylic acid, succinic anhydride, maleic anhydride, glutaric anhydride, phthalic anhydride, acid anhydrides such as propionic anhydride, benzoic anhydride, maleic acid ester, malonic acid ester, succinic acid ester, glutaric acid ester, ethyl acetate Aromatic esters such as esters, phthalic acid esters, isophthalic acid esters, terephthalic acid esters, ethyl-m-aminobenzoate and methyl-p-hydroxybenzoate, ketones such as quinones, anthraquinones and naphthoquinones, glycine, trisine, Bixin, alanine, varine, leucine, serine, threonine, lysine, aspartic acid, glutamic acid, cysteine, methionine, proline, N- (p-aminobenzoyl) -β-alanine Amino acid, maleinamide, maleinamide acid (maleinamide), succinic acid monoamide, 5-hydroxyvaleramide, N-acetylethanolamine, N, N'-hexamethylenebisacetoamide, malonamide, Amides such as cycloserine, 4-acetoamide phenol and p-acetoamide benzoic acid, and imides such as maleimide and succinimide.

In addition, the heterocyclic amine containing group is introduced from a nitrogen containing heterocyclic or a compound containing the heterocyclic. The nitrogen-containing heterocyclic may be any structure containing a hydrogen bondable amino group or a hydrogen bondable amino group in the heterocyclic. Such nitrogen-containing heterocyclics include, for example, pyrrole, histidine, imidazole, triazolidine, triazole, triazine, pyridine, pyrimidine, pyrazine, indole, quinoline, purine, phenazine, pteridine, Melamine and the like. The nitrogen-containing heterocyclic may contain other hetero atoms in cyclic. In addition, the compound containing a nitrogen-containing heterocyclic may be the one having such a heterocyclic backbone, and is not particularly limited. For example, a group capable of chemically (covalently) bonding with the main chain carbon of the elastomeric polymer. Can have As such a group, an amino group, a hydroxyl group, a methylene group, ethylene group, carboxylic acid, etc. are mentioned, for example. Specific examples of such compounds containing nitrogen-containing heterocyclic compounds include dipyridyl, ethylenedipyridyl, trimethylenedipyridyl, dipyridylamine, 1,2-dimethylimidazole and 2-benzimidazole urea. , Pyrrole-2-carboxylic acid, 3-methyl-pyrazole, pyridine, 4-methylpyridine, 4 (or 2) -hydroxymethylpyridine, 2 (or 4)-(β-hydroxyethyl) -pyridine, 2 ( Or 4)-(2-aminoethyl) -pyridine, 2 (or 4) -aminopyridine, 2,6-diaminopyridine, 2-amino-6-hydroxypyridine, 6-azatimine, acetoguanamine, benzo Guanamine, citric acid, 1,2,4-triazole, 3-amino-1,2,4-triazole, 3-aminomethyl-1,2,4-triazole, 3-methylamino-1, 2,4-triazole, 3-methylol-1,2,4-triazole, 3-hydroxy-1,2,4-triazole, 2-hydroxytriazine, 2-aminotriazine, 2- Hydroxy-5-methyltriazine, 2-amino-5-methyltriazine, 2-hydroxypyrimidine, 2-aminopi Limidine, 2-aminopyrazine, 2-hydroxypyrazine, 6-aminopurine, 6-hydroxypurine, etc. are mentioned.

The thermoplastic elastomer used in the present invention is composed of an elastomeric polymer having a carbonyl group-containing group and a heterocyclic amine-containing group in the side chain and in one molecule. The carbonyl group-containing group and the heterocyclic amine-containing group are pendant to the side chain of the elastomeric polymer, and have the above chemically stable bonds. In this case, the carbonyl group-containing group and the heterocyclic amine-containing group may be bonded to the polymer main chain as side chains independent of each other, and may also be bonded to the main chain through different groups to thereby form a carbonyl group-containing group and a heterobetween. One side chain may be formed with a click amine containing group. As described above, when one side chain is formed of the carbonyl group-containing group and the heterocyclic amine-containing group, not only the bond with the main chain is chemically bonded to the carbonyl group-containing group and the heterocyclic amine-containing group. Such carbonyl group-containing group and heterocyclic amine-containing group may be bonded through any bond.

The material constituting the elastic ring 5 of the present invention may further be blended with various additives generally blended with conventional crosslinking accelerators, various oils, anti-aging agents, fillers, plasticizers, and other general rubber applications. The compounding quantity of can also be made into a general compounding quantity, unless it opposes the objective of this invention.

Hereinafter, although an Example further demonstrates this invention, the scope of the present invention is not limited to these Examples.

Examples 1 to 9, Conventional Example 1 and Comparative Example 1

The formulations (parts by weight) of the tires of Conventional Example 1, Comparative Example 1 and Examples 1 to 9 according to the conventional method are shown in Tables I to III, the tire size is 205 / 55R16 89V and the rim size is 16 × 6 1 The tire wheel assembly was produced at / 2JJ, respectively.

Each of these test tire wheel assemblies was subjected to the durability evaluation test by the measuring method shown below. The results are shown in Tables I-III.

Durability test

The test tire was mounted on a 2500cc passenger car, and the tire was run at 90 km / hr until the tire pressure at the front right was 0 kPa and the tire pressure at the other three positions was 200 kPa. The results were displayed exponentially with the value of Conventional Example 1 as 100. The larger the value, the better the durability.

As described above, according to the present invention, the elastic ring constituting the intermediate body for the run flat tire is composed of a thermoplastic elastomer composition in which the rubber composition (B) is dispersed in the thermoplastic resin (A), preferably by dynamic vulcanization. Alternatively, by constructing a hydrogen bondable thermoplastic elastomer having a carbonyl group-containing group and a heterocyclic amine-containing group in the side chain or a composition thereof, a recyclable elastic ring having a load bearing capacity at high temperatures during run-flat driving can be obtained. .

Claims (7)

In a tire wheel assembly equipped with a run-flat heavyweight body in which a thin and rigid annular shell is supported on a rim by an elastic ring at an inner cavity of a tire / rim, the elastic ring is a thermoplastic resin ( A tire wheel assembly comprising a thermoplastic elastomer composition having a structure in which a rubber composition (B) is dispersed in A). The melting point of the thermoplastic resin (A) constituting the elastic ring is 150 ° C or more, and the weight ratio (A) / (B) of the thermoplastic resin (A) and the rubber composition (B) is 80/20 to 25. / 75, tire wheel assembly. The tire wheel assembly according to claim 1 or 2, wherein the rubber composition (B) is dynamically vulcanized during kneading. The thermoplastic resin (A) according to any one of claims 1 to 3, wherein the thermoplastic resin (A) consists of a polyamide resin, a polyester resin, a polynitrile resin, a polyolefin resin, a polyvinyl resin, a polyphenylene oxide resin, and a polyimide resin. A tire wheel assembly, which is at least one thermoplastic resin selected from the group. In a tire wheel assembly equipped with a run-flat heavyweight body in which a thin rigid rigid annular shell is supported on the rim by an elastic ring in the inner cavity of the tire / rim, the elastic ring is a hetero group containing a carbonyl group and a hetero group. A tire wheel assembly comprising a hydrogen bondable thermoplastic elastomer consisting of an elastomeric polymer having a cyclic amine containing group in the side chain and / or a composition of the thermoplastic elastomer. The ratio (S / R) of the nominal inner diameter (R) (inch) of the tire to the adhesion area (S) (cm 2) of the rubber / metal is 4.5 cm 2 / inch according to claim 1. That is, the tire wheel assembly. 7. The tire wheel assembly of claim 6, wherein the adhesive surface is constituted by an approximately axial surface and an approximately radial surface.