JP4079709B2 - Tire wheel assembly and run-flat support - Google Patents

Description

この表１に示すように、実施例１〜３のタイヤホイール組立体はいずれも突起乗り越し時の衝撃緩和能力が従来よりも優れていた。
【００３３】
【発明の効果】
以上説明したように本発明によれば、支持面を外周側に張り出しつつ該支持面の両側に沿って脚部を持つ環状シェルと、該環状シェルの脚部をリム上に支持する弾性リングとからなるランフラット用支持体について、弾性リングに弾性率が互いに異なる複数の弾性層を設け、これら弾性層をリング径方向に積層すると共に、弾性リングに含まれる複数の弾性層において、最も高い弾性率を最も低い弾性率の１２０〜３００％としたから、ランフラット走行性能を損なうことなく突起乗り越し時などに受ける衝撃を緩和することができる。その結果、搭乗者への不快感を低減し、またランフラット用支持体の耐久性を向上することができる。
【図面の簡単な説明】
【図１】本発明の実施形態からなるタイヤホイール組立体の要部を示す子午線断面図である。
【図２】図１における環状シェルと弾性リングとの接合部を拡大して示す断面図である。
【図３】（ａ）〜（ｃ）はそれぞれ本発明における弾性リングの変形例を示す断面図である。
【図４】（ａ）〜（ｂ）はそれぞれ本発明における弾性リングにカバー材を付加した変形例を示す断面図である。
【符号の説明】
１（ホイールの）リム
２ 空気入りタイヤ
３ ランフラット用支持体
４ 環状シェル
４ａ 支持面
４ｂ 脚部
５ 弾性リング
５ａ，５ｂ 弾性層
６ カバー材[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a tire wheel assembly that enables run flat running and a run flat support used therefor, and more particularly, a tire wheel assembly and run flat for reducing impact received when riding over a protrusion. It relates to a support.
[0002]
[Prior art]
Many technologies for enabling a certain degree of emergency traveling have been proposed in response to market demands even when a pneumatic tire is punctured while the vehicle is traveling. Among these many proposals, the technique proposed in Japanese Patent Application Laid-Open No. 10-297226 and Japanese Patent Application Publication No. 2001-519279 discloses a technique in which a core is mounted on a rim in a hollow portion of a pneumatic tire assembled with a rim. The run-flat running is made possible by supporting the tire with a core.
[0003]
The run-flat core has an open-legged annular shell having leg portions along both sides of the support surface while projecting the support surface to the outer peripheral side, and has an elastic ring attached to both leg portions. The elastic ring is supported on the rim. This run-flat core has the advantage that it can be used without causing confusion in the market because it can be used as it is without any special modifications to existing wheels and rims.
[0004]
However, although the core as described above functions effectively in run-flat running, for example, when a tire with a low internal pressure gets over a large protrusion, if the core collides with the protrusion through the tire, a large impact is generated. There was a problem that occurred. Such an impact not only makes the passenger uncomfortable, but also adversely affects the durability of the core.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a tire-wheel assembly and a run-flat support body having a function of alleviating an impact received when a protrusion is passed over.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a tire / wheel assembly according to the present invention fits a pneumatic tire to a rim of a wheel, and extends a support surface to the outer peripheral side of the cavity of the pneumatic tire while extending the support surface to the outer peripheral side. In a tire-wheel assembly in which a run-flat support body including an annular shell having legs along both sides and an elastic ring that supports the legs of the annular shell on a rim is inserted, the elastic modulus of the elastic ring is A plurality of different elastic layers are provided, and these elastic layers are laminated in the ring radial direction , and the highest elastic modulus is set to 120 to 300% of the lowest elastic modulus in the plurality of elastic layers included in the elastic ring. It is characterized by.
[0007]
The run-flat support of the present invention includes an annular shell having legs along both sides of the support surface while projecting the support surface to the outer peripheral side, and an elastic ring for supporting the legs of the annular shell on the rim. The elastic ring is provided with a plurality of elastic layers having different elastic moduli, and these elastic layers are laminated in the radial direction of the ring, and the highest elastic modulus among the plurality of elastic layers included in the elastic ring is the highest. The low elastic modulus is 120 to 300% .
[0008]
In the present invention, the run-flat support body is formed with an outer diameter smaller than the inner diameter of the tread portion of the pneumatic tire so as to maintain a certain distance from the pneumatic tire, and the inner diameter of the bead portion of the pneumatic tire. It is formed to have substantially the same dimensions as the inner diameter. The run-flat support body is assembled to the rim of the wheel together with the pneumatic tire in a state where the run-flat support body is inserted into the hollow portion of the pneumatic tire, thereby constituting a tire wheel assembly. When a pneumatic tire is punctured while the tire / wheel assembly is mounted on a vehicle, the punctured and crushed tire is supported by the support surface of the annular shell of the run-flat support body. Driving is possible.
[0009]
According to the present invention, the elastic ring is provided with a plurality of elastic layers having different elastic moduli, and these elastic layers are laminated in the ring radial direction. For example, when a tire having a low internal pressure gets over a large protrusion, When the run-flat support body collides with the protrusion via the tire, the impact can be mitigated based on the elastic layer having a low elastic modulus. As a result, discomfort to the passenger can be reduced, and the durability of the run-flat support can be improved. On the other hand, during the run-flat running, the annular shell can be stably supported based on the elastic layer having a high elastic modulus.
[0010]
In the present invention, it is preferable that the elastic layer having the lowest elastic modulus among the plurality of elastic layers included in the elastic ring is disposed on the rim side. Further, a plurality of elastic layers included in the elastic ring, the highest modulus and 120-300% of the lowest modulus. Thereby, a high impact relaxation capability can be exhibited while stably supporting the annular shell.
[0011]
Further, in the plurality of elastic layers included in the elastic ring, at least a part of both side surfaces of the elastic layer having the lowest elastic modulus is covered with a cover material having a higher elastic modulus than the elastic layer having the highest elastic modulus. It is preferable to do. This makes it possible to adjust the nonlinearity of the rigidity of the elastic ring. In particular, when the cover material is integrated with the annular shell, the coupling between the annular shell and the elastic ring can be further stabilized.
[0012]
The present invention is particularly effective when the run-flat support has the above-described annular shell, but can also be applied to a run-flat support having an annular rigid body other than the above-described annular shell.
[0013]
That is, the tire-wheel assembly of the present invention fits a pneumatic tire to a rim of the wheel, supports an annular rigid body having a support surface in the hollow portion of the pneumatic tire, and supports the rigid body on the rim. A tire-wheel assembly in which a run-flat support made of an elastic ring is inserted, wherein the elastic ring is provided with a plurality of elastic layers having different elastic moduli, and the elastic layers are laminated in the ring radial direction. Is.
[0014]
The run-flat support body of the present invention comprises an annular rigid body having a support surface and an elastic ring that supports the rigid body on a rim, and the elastic ring is provided with a plurality of elastic layers having different elastic moduli. These elastic layers are laminated in the ring radial direction.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
[0016]
FIG. 1 is a meridian cross-sectional view showing the main part of a tire wheel assembly (wheel) according to an embodiment of the present invention, wherein 1 is a wheel rim, 2 is a pneumatic tire, and 3 is a run-flat support. The rim 1, the pneumatic tire 2, and the run-flat support body 3 are formed in an annular shape around a wheel rotation shaft (not shown).
[0017]
The run-flat support 3 includes an annular shell 4 and an elastic ring 5 as main parts. The run-flat support 3 is spaced apart from the inner wall surface of the pneumatic tire 2 during normal running, but supports the collapsed pneumatic tire 2 from the inside during puncture.
[0018]
The annular shell 4 projects a continuous support surface 4a for supporting a punctured tire to the outer peripheral side (radially outer side) and has leg portions 4b and 4b along both sides of the support surface 4a. It has become. The support surface 4a of the annular shell 4 is formed so that the shape in a cross section perpendicular to the circumferential direction thereof is a convex curved surface on the outer peripheral side. At least one convex curved surface may be present, but it is preferable that two or more convex curved surfaces are arranged in the tire axial direction. In this way, by forming the support surface 4a of the annular shell 4 so that two or more convex curved surfaces are arranged side by side, the contact portion of the support surface 4a with respect to the tire inner wall surface is dispersed into two or more, and the local portion is given to the tire inner wall surface. In order to reduce wear, the run distance of run-flat travel can be extended.
[0019]
The annular shell 4 is made of a rigid material because it needs to support the vehicle weight via the punctured pneumatic tire 2. As the constituent material, metal, resin, or the like is used. Among these, steel, aluminum, etc. can be illustrated as a metal. Further, the resin may be either a thermoplastic resin or a thermosetting resin. Examples of the thermoplastic resin include nylon, polyester, polyethylene, polypropylene, polystyrene, polyphenylene sulfide, and ABS. Examples of the thermosetting resin include an epoxy resin and an unsaturated polyester resin. The resin may be used alone, or may be used as a fiber reinforced resin by blending reinforcing fibers.
[0020]
The elastic rings 5 are attached to the leg portions 4b and 4b of the annular shell 4, respectively, and support the annular shell 4 while abutting on the left and right rim seats. The elastic ring 5 reduces the impact and vibration received by the annular shell 4 from the punctured pneumatic tire 2, and prevents the slip against the rim seat to stably support the annular shell 4.
[0021]
As a constituent material of the elastic ring 5, rubber or resin can be used, and rubber is particularly preferable. As rubber, natural rubber (NR), isoprene rubber (IR), styrene-butadiene rubber (SBR), butadiene rubber (BR), hydrogenated NBR, hydrogenated SBR, ethylene propylene rubber (EPDM, EPM), butyl rubber (IIR) ), Acrylic rubber (ACM), chloroprene rubber (CR) , silicone rubber, fluorine rubber and the like. Of course, additives such as a filler, a vulcanizing agent, a vulcanization accelerator, a softening agent and an anti-aging agent can be appropriately blended with these rubbers. And a desired elasticity modulus can be obtained based on the mixing | blending of a rubber composition.
[0022]
FIG. 2 is an enlarged view of the joint portion between the annular shell 4 and the elastic ring 5. As shown in FIG. 2, in the tire wheel assembly, the elastic ring 5 is formed with a plurality of elastic layers 5a and 5b having different elastic moduli, and these elastic layers 5a and 5b are laminated in the ring radial direction. . However, the elastic modulus is a modulus at 100% elongation at 60 ° C. Here, an elastic layer 5a made of low modulus rubber is arranged on the shell side, and an elastic layer 5b made of high modulus rubber is arranged on the rim side.
[0023]
In the tire-wheel assembly configured as described above, for example, when the pneumatic tire 2 gets over a large protrusion while the internal pressure is low, an elastic layer having a low elastic modulus when the run-flat support body 3 collides with the protrusion. The impact can be reduced based on 5a. On the other hand, when the pneumatic tire 2 is punctured during traveling, the crushed pneumatic tire 2 is supported by the support surface 4a of the annular shell 4 of the run-flat support 3 so that run-flat traveling is possible. . During the run-flat running, the annular shell 4 can be stably supported based on the elastic layer 5b having a high elastic modulus.
[0024]
3A to 3C show modifications of the elastic ring. As shown in FIGS. 3A to 3C, when the elastic layer 5a made of low modulus rubber is arranged on the rim side with respect to the elastic layer 5b made of high modulus rubber, the stability of the annular shell 4 is improved. High impact mitigation ability can be exhibited while sufficiently securing. Moreover, the cross-sectional shape of the elastic layers 5a and 5b is not particularly limited.
[0025]
In the elastic layers 5a and 5b included in the elastic ring 5, the highest elastic modulus is 120 to 300% of the lowest elastic modulus . If this ratio is too small, the shock-absorbing capacity becomes insufficient. Conversely, if it is too large, the support of the annular shell 4 becomes unstable.
[0026]
4 (a) to 4 (b) show a modification in which a cover material is added to an elastic ring. FIG. 4A shows a case where the elastic layer 5a made of low modulus rubber is arranged on the shell side and the elastic layer 5b made of high modulus rubber is arranged on the rim side, and the cover material 6 is made of the elastic layer 5b. The elastic layer 5a has a higher elastic modulus and covers the radially outer end surface of the elastic layer 5a and at least a part of both side surfaces of the elastic layer 5a. In this case, the nonlinearity of the rigidity of the elastic ring 5 can be adjusted, and the cover member 6 can be integrated with the annular shell 4 to further stabilize the coupling between the annular shell 4 and the elastic ring 5. it can.
[0027]
On the other hand, FIG. 4B shows a case where the elastic layer 5a made of low modulus rubber is arranged on the rim side, and the elastic layer 5b made of high modulus rubber is arranged on the shell side. The elastic layer 5b has a higher elastic modulus than the layer 5b, and covers the radially inner end surface of the elastic layer 5a and at least a part of both side surfaces of the elastic layer 5a. In this case, the nonlinearity of the rigidity of the elastic ring 5 can be adjusted.
[0028]
【Example】
In a tire / wheel assembly of a pneumatic tire with a tire size of 205 / 55R16 89V and a wheel with a rim size of 16 × 6 1 / 2JJ, an annular shell is machined from a steel plate with a thickness of 1.0 mm, and the legs are A two-layered elastic ring made of two types of hard rubbers with different elastic moduli is joined to produce a run-flat support body, and the run-flat support body is inserted into a hollow portion of a pneumatic tire to form a tire wheel. An assembly (Examples 1 to 3) was obtained. In Examples 1 to 3, the ratio of the highest elastic modulus to the lowest elastic modulus (ratio of elastic modulus) was varied in the plurality of elastic layers included in the elastic ring.
[0029]
For comparison, except that a single-layer elastic ring made of hard rubber is joined to the leg of the annular shell to produce a run-flat support, and the run-flat support is used. A tire wheel assembly (conventional example) having the same structure as that of the example was obtained.
[0030]
The above four types of tire wheel assemblies were evaluated for impact mitigation ability when overhanging protrusions by the following measurement method, and the results are shown in Table 1.
[0031]
[Shock mitigation ability when riding over bumps]
Using a drum tester having a 100 mm high protrusion on the outer peripheral surface of the drum, the tire wheel assembly to be tested is mounted on the drum tester, and the protrusion is overcome when the internal pressure is 100 kPa and the speed is 30 km / h. The impact force was measured. The evaluation results are shown as an index with the conventional example being 100, using the reciprocal of the measured value. The larger the index value, the better the impact relaxation ability.
[0032]
[Table 1]

As shown in Table 1, the tire wheel assemblies of Examples 1 to 3 were all superior in impact mitigation ability over the protrusion.
[0033]
【The invention's effect】
As described above, according to the present invention, an annular shell having legs along both sides of the support surface while projecting the support surface to the outer peripheral side, and an elastic ring for supporting the legs of the annular shell on the rim. A plurality of elastic layers having different elastic moduli are provided on the elastic ring, and the elastic layers are laminated in the radial direction of the ring, and the elastic layer included in the elastic ring has the highest elasticity. Since the modulus is set to 120 to 300% of the lowest elastic modulus, it is possible to alleviate the impact received when riding over the protrusion without impairing the run-flat running performance. As a result, discomfort to the passenger can be reduced, and the durability of the run-flat support can be improved.
[Brief description of the drawings]
FIG. 1 is a meridian cross-sectional view showing a main part of a tire wheel assembly according to an embodiment of the present invention.
2 is an enlarged cross-sectional view showing a joint portion between an annular shell and an elastic ring in FIG. 1;
FIGS. 3A to 3C are cross-sectional views showing modifications of the elastic ring in the present invention.
FIGS. 4A to 4B are cross-sectional views showing modifications in which a cover material is added to the elastic ring in the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 (Wheel) rim 2 Pneumatic tire 3 Run-flat support body 4 Ring shell 4a Support surface 4b Leg part 5 Elastic ring 5a, 5b Elastic layer 6 Cover material

Claims (12)

A pneumatic tire is fitted to a rim of a wheel, and an annular shell having legs along both sides of the support surface while projecting a support surface to the outer peripheral side in the hollow portion of the pneumatic tire, In a tire / wheel assembly in which a run-flat support body including an elastic ring for supporting a leg portion on a rim is inserted, a plurality of elastic layers having different elastic moduli are provided on the elastic ring, and the elastic layers are arranged in a ring radial direction. And a tire wheel assembly in which the highest elastic modulus of the plurality of elastic layers included in the elastic ring is 120 to 300% of the lowest elastic modulus .   The tire wheel assembly according to claim 1, wherein an elastic layer having the lowest elastic modulus among a plurality of elastic layers included in the elastic ring is disposed on the rim side. In the plurality of elastic layers included in the elastic ring, at least a part of both side surfaces together with the radial end surface of the elastic layer having the lowest elastic modulus is covered with a cover material having a higher elastic modulus than the elastic layer having the highest elastic modulus. tire-wheel assembly as claimed in any of claims 1-2. A pneumatic tire is fitted to a rim of a wheel, and a run-flat support body comprising an annular rigid body having a support surface and an elastic ring for supporting the rigid body on the rim in a hollow portion of the pneumatic tire. In the inserted tire wheel assembly, the elastic ring is provided with a plurality of elastic layers having different elastic moduli, and the elastic layers are stacked in the radial direction of the ring, and the highest among the plurality of elastic layers included in the elastic ring. A tire-wheel assembly having an elastic modulus of 120 to 300% of the lowest elastic modulus . The tire wheel assembly according to claim 4, wherein an elastic layer having the lowest elastic modulus among the plurality of elastic layers included in the elastic ring is disposed on the rim side. In the plurality of elastic layers included in the elastic ring, at least a part of both side surfaces together with the radial end surface of the elastic layer having the lowest elastic modulus is covered with a cover material having a higher elastic modulus than the elastic layer having the highest elastic modulus. The tire wheel assembly according to any one of claims 4 to 5. An annular shell having leg portions along both sides of the support surface while projecting the support surface to the outer peripheral side, and an elastic ring that supports the leg portions of the annular shell on the rim. A plurality of different elastic layers are provided, and these elastic layers are laminated in the radial direction of the ring, and in the plurality of elastic layers included in the elastic ring, the highest elastic modulus is 120 to 300% of the lowest elastic modulus. Support. The run-flat support body according to claim 7 , wherein the elastic layer having the lowest elastic modulus among the plurality of elastic layers included in the elastic ring is disposed on the rim side. In the plurality of elastic layers included in the elastic ring, at least a part of both side surfaces together with the radial end surface of the elastic layer having the lowest elastic modulus is covered with a cover material having a higher elastic modulus than the elastic layer having the highest elastic modulus. run-flat support body according to any one of claims 7-8. An annular rigid body having a support surface and an elastic ring that supports the rigid body on the rim, and a plurality of elastic layers having different elastic moduli are provided on the elastic ring, and these elastic layers are laminated in the ring radial direction. In the plurality of elastic layers included in the elastic ring, a run-flat support body in which the highest elastic modulus is 120 to 300% of the lowest elastic modulus . The run-flat support body according to claim 10, wherein the elastic layer having the lowest elastic modulus among the plurality of elastic layers included in the elastic ring is disposed on the rim side. In the plurality of elastic layers included in the elastic ring, at least a part of both side surfaces together with the radial end surface of the elastic layer having the lowest elastic modulus is covered with a cover material having a higher elastic modulus than the elastic layer having the highest elastic modulus. The support body for run flats in any one of Claims 10-11.

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