JP2004148935A - Support body and pneumatic run-flat tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightweight support body while keeping stability and durability high during run-flat running, and a pneumatic run-flat tire for realizing weight reduction. <P>SOLUTION: The annular support body 16 is disposed inside the pneumatic tire 14, is assembled to a rim 12 together with the pneumatic tire 14, and can support a load during the run-flat running. The support body 16 has a stacked structure having three or more layers, an uppermost layer 26a and a lowermost layer 26c are metal layers made of metal, at least one resin layer 26b made of resin is formed between the uppermost layer 26a and the lowermost layer 26c. The pneumatic run-flat tire has the support body. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an annular support disposed inside a tire so that it can travel a considerable distance in a punctured state in a punctured state, and a pneumatic run-flat tire including the support.
[0002]
[Prior art]
Run-flat running is possible with a pneumatic tire, that is, a tire that can run with a certain distance without worry even if the tire internal pressure becomes 0 kg / cm ^{2 due} to puncturing (hereinafter referred to as a run-flat tire). A core type in which an annular core (support) made of metal such as iron or a synthetic resin is attached to a rim portion in a tire air chamber is known.
[0003]
As the core type, a rotary core type incorporated in a rim and a core type having two convex portions in a tire radial cross section attached to the rim (a double mountain shape) are known (for example, Patent Document 1). 1). The rotating core type has a problem in versatility in that a special wheel for fixing the rotating core is required. On the other hand, the double-core type is highly versatile because it can be attached to a conventional rim. As a core (support) in such a run flat tire, one thin metal plate has been used.
[0004]
[Patent Document 1]
JP 10-297226 A
[Problems to be solved by the invention]
By the way, the weight of the support is reduced in order to improve the fuel efficiency and the running stability during running. Specifically, the thickness of the support may be reduced. However, when the thickness of the support is reduced, the rigidity of the support itself is reduced. That is, if the thickness is reduced, the run-flat function is lost due to damage such as crushing or cracking of the two-peaked mountain portion during actual vehicle running.
[0006]
The present invention, in consideration of the above facts, provides a lightweight support while maintaining high stability and durability during run flat running, and also provides a pneumatic run that achieves weight reduction. The purpose is to provide a flat tire.
[0007]
[Means for Solving the Problems]
The above object is solved by the present invention described below.
That is, the present invention is an annular support that is disposed inside a pneumatic tire and is mounted on a rim together with the pneumatic tire, and that can support a load during run-flat running, wherein the support has three or more layers. It has a laminated structure, wherein the uppermost layer and the lowermost layer are metal layers made of metal, and at least one resin layer made of a resin is formed between the uppermost layer and the lowermost layer. Support.
By providing upper and lower metal layers made of a metal and providing a resin layer having a low specific gravity between them, the mass can be reduced as compared with using a metal plate having the same thickness as a support.
[0008]
It is preferable that legs to be attached to the rim when the rim is assembled are provided at both ends of the support. Providing the legs can improve workability when the support is incorporated into the rim.
When spot welding is required, the resin layer preferably contains metal powder, and the content is preferably 5 to 50% by mass of the mass of the resin layer.
[0009]
Further, the present invention is a pneumatic runflat tire provided with an annular support that is disposed inside a pneumatic tire, is assembled to the rim together with the pneumatic tire, and can support a load during runflat running. The pneumatic run-flat tire is characterized in that the support is a support in the above-described embodiment.
The support used for the run flat tire of the present invention is reduced in weight as described above. Therefore, the mass of the tire as a whole can be reduced.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
A pneumatic run flat tire according to one embodiment of the present invention will be described with reference to FIG.
Here, the run-flat tire 10 refers to a rim 12 in which a pneumatic tire 14 and a support 16 are assembled, as shown in FIG. The rim 12 is a standard rim corresponding to the size of the pneumatic tire 14.
As shown in FIG. 1, the pneumatic tire 14 includes a pair of bead portions 18, a toroidal carcass 20 extending across both the bead portions 18, and a plurality of carcass 20 located in a crown portion of the carcass 20 (the present embodiment). (2 sheets in FIG. 2) and a tread portion 24 formed on the belt layer 22.
The support 16 disposed inside the pneumatic tire 14 has the cross-sectional shape shown in FIG. 1 formed in a ring shape, and is vulcanized and formed at both ends of the support 26 and the support 26. And a leg 28 made of rubber. The leg 28 is fixed to the rim 12 by being assembled to the rim 12.
[0011]
The support portion 26 of the support 16 has a three-layer structure in which the uppermost layer 26a and the lowermost layer 26c are metal layers made of a metal, and a resin layer 26b made of a resin is formed therebetween. .
By providing thin metal layers on the upper and lower sides and forming a resin layer with a low specific gravity between them, the weight can be reduced as compared with the case where the support portion having the same thickness is formed of one metal plate (steel plate). In addition, by adopting a laminated structure, the same rigidity as that of a single metal plate can be obtained, so that the running characteristics of the run flat tire are not reduced.
[0012]
The metal layer can be made of iron, steel, SUS, aluminum, magnesium, or the like, but is not particularly limited. The thickness of the metal layers such as the uppermost layer 26a and the lowermost layer 26c is preferably 0.05 to 1.0 mm, and more preferably 0.1 to 0.8 mm. The materials and thicknesses of the metal layers such as the uppermost layer 26a and the lowermost layer 26c may be the same or different.
[0013]
As the resin applied to the resin layer 26c, polypropylene, polyethylene, polyurethane, polyester, polyamide, or the like is appropriately used. The thickness of the resin layer 26c is preferably 0.1 to 1.5 mm, more preferably 0.2 to 1.0 mm. In addition, the thickness of the resin layer 26c (when there are a plurality of resin layers, the thickness of each layer) is preferably in the range of 50 to 400% of the thickness of the thickest layer among the metal layers. More preferably, it is set to about 300%. If it is less than 50%, the resin portion having a small specific gravity is reduced, and the effect of reducing the weight may not be sufficiently exhibited. If it exceeds 400%, the thickness of the metal layer becomes so small that sufficient rigidity as a support may not be obtained.
[0014]
Further, the resin layer 26c preferably contains metal powder. Since the resin is insulative, when spot welding is required, the conductivity of the resin layer 26c can be imparted by including metal powder in the resin layer 26c.
[0015]
Examples of the metal powder include iron, nickel, aluminum, SUS, and magnesium. The content of the metal powder is preferably 5 to 50% by mass of the mass of the resin layer, and more preferably 15 to 35% by mass.
[0016]
The support shown in FIG. 1 has a three-layer structure in which a resin layer is formed between the uppermost layer and the lowermost layer, but the present invention is not limited to this. That is, the intermediate resin layer may be composed of a plurality of layers, and the materials constituting the respective layers may be different from each other, or may be a multi-layer constitution such as a metal layer / resin layer / metal layer / resin layer / metal layer. Is also good.
Further, the bonding between the metal layer and the resin layer can be performed by various known means.
[0017]
The material of the leg 28 is preferably a rubber material in consideration of running stability and durability.
Specifically, it may be a vulcanized rubber, urethane rubber, or the like, which is a natural rubber, IR (isoprene rubber), BR (butadiene rubber), SBR (styrene butadiene rubber), IIR (butyl rubber), or the like, alone or compounded. It is more preferable to use urethane-based rubber or the like, particularly from the viewpoint that carbon having a high density need not be blended.
Further, the shape of the leg portion 28 is not limited to the shape shown in the drawings, but may be various shapes depending on the use and the like.
[0018]
In this specification, the standard rim is a rim specified in JATMA (Japan Automobile Tire Association) Year Book 2002 edition, and the standard load is a single wheel of JATMA (Japan Automobile Tire Association) Year Book 2002 edition. This is the load equivalent to the maximum load capacity when the load is applied.
Outside Japan, the load is the maximum load (maximum load capacity) of a single wheel at the applicable size described in the following standard, and the internal pressure is the maximum load (maximum load of the single wheel) described in the following standard Rim) is the air pressure corresponding to the standard rim (or '' Approved '') in the applicable size described in the following standard.
Rim '', '' Recommended Rim '').
Standards are determined by industry standards that are in effect in the area where the tire is manufactured or used. For example, in the United States, '' The Tire and Rim Association Inc. In Europe, it is "Standards Manual" of The European Tire and Rim Technical Organization.
[0019]
In the run-flat tire of the present invention as described above, when the internal pressure of the pneumatic tire 14 decreases, the tread portion 24 of the pneumatic tire 14 is moved to the convex portion of the support 16 (the radial direction of the support 16 in the drawing). The protruding part) can be supported and run.
At this time, if a lubricant or the like is applied to the back surface of the tread portion 24 or the convex portion of the support 16, the wear resistance can be improved, and the durability can be further improved.
[0020]
【Example】
The present invention will be specifically described with reference to the following examples, but the present invention is not limited to these examples.
[0021]
(Example)
A SUS304 plate (thickness 0.35 mm) is used as the uppermost layer and the lowermost layer, and a polypropylene film (thickness 0.6 mm) is used as a resin layer provided therebetween. The film was sandwiched between them, and heated and pressed by a hot press (150 ° C., 1 minute) to bond them, thereby producing a laminate. Next, this laminate was formed into a ring with three rolls and welded to be integrated. This ring-shaped laminate was molded into a two-peak shape, and both ends were vulcanized and bonded with natural rubber to provide legs, thereby producing the support shown in FIG.
In addition, iron powder was mixed in a polypropylene film at 25% by mass so that spot welding could be performed.
[0022]
It has the same configuration as the pneumatic run-flat tire described in the embodiment (see FIG. 1), and inserts a manufactured support into a 205 / 70R15 size pneumatic tire and inserts it into a standard rim ( 6J) (the legs of the support were fixed to the rim by fixing the legs of the support) to produce a run flat tire.
[0023]
A run test was performed in which the produced run flat tire was mounted on a passenger car and the air pressure of only one wheel was zero, and a run flat run of 400 km was performed.
[0024]
(Comparative example)
A run-flat tire was manufactured in the same manner as in the example, except that a SUS304 plate (thickness: 1.3 mm) was used as the support portion of the support, and a running test was performed in the same manner as in the example.
[0025]
When the masses of the supports produced in the example and the comparative example were compared, in the example, since the support was a laminated structure and the middle was a resin layer, it was confirmed that the weight was reduced by about 40% as compared with the comparative example. . Also, in the running test, it was confirmed that running at the same level as that of the comparative example was possible, and it was found that the rigidity of the support was equivalent to that of the comparative example. From these results, an effect of improving fuel efficiency can be expected.
[0026]
【The invention's effect】
As described above, although the support of the present invention is lighter than the conventional support, stability and durability during run-flat running can be maintained in a high state. In addition, by equipping the support with the pneumatic run-flat tire of the present invention, it is possible to achieve weight reduction while maintaining high stability and durability during run-flat running.
[Brief description of the drawings]
FIG. 1 is a sectional view of a pneumatic run-flat tire according to an embodiment of the present invention when a rim is mounted.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Pneumatic run flat tire 12 Rim 14 Pneumatic tire 16 Support 24 Tread part 26 Support part 26a Top layer 26b Resin layer 26c Bottom layer 28 Leg

Claims (5)

An annular support that is disposed inside the pneumatic tire and is attached to the rim together with the pneumatic tire, and is capable of supporting a load during run flat running,
The support has a laminated structure of three or more layers, an uppermost layer and a lowermost layer are metal layers made of metal, and at least one resin layer made of a resin is provided between the uppermost layer and the lowermost layer. A support characterized by being formed. 2. The support according to claim 1, wherein legs mounted on the rim when the rim is assembled are provided at both ends. The support according to claim 1, wherein the resin layer contains metal powder. The support according to any one of claims 1 to 3, wherein the content of the metal powder is 5 to 50% by mass of the mass of the resin layer. A pneumatic run-flat tire provided with an annular support capable of supporting a load during run-flat running, the pneumatic run-flat tire being disposed inside a pneumatic tire and assembled to the rim together with the pneumatic tire,
A pneumatic run-flat tire, wherein the support is the support according to any one of claims 1 to 4.

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