JP2008132951A - Non-pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-pneumatic tire improved in load supporting ability and rolling resistance without increasing the weight thereof, in regard to the non-pneumatic tire having spoke structure. <P>SOLUTION: In this non-pneumatic tire having the spoke structure 3 constituted by coupling an annular peripheral member 4 with an annular inner peripheral member 5 through spokes 6 formed of rubber or resin, a metal layer 8 is attached to at least the radial directional surface 7 of the spoke 6. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a non-pneumatic tire, and more particularly, to a non-pneumatic tire with improved load bearing capacity and rolling resistance.

  Conventionally, as for non-pneumatic tires, solid tires or cushion tires having a solid rubber structure are mainly used for industrial vehicles. However, conventional non-pneumatic tires have not been adopted for passenger cars where ride comfort is important because they are heavy and lack shock absorption.

  In order to improve the riding comfort performance of such a non-pneumatic tire and make it applicable to passenger cars as well, rubber or resin is provided between the tread ring 1 and the wheel 11 as shown in FIG. A non-pneumatic tire comprising a spoke structure 3 in which an outer circumferential member 4 and an inner circumferential member 5 serving as constituent members are connected by spokes 6 in the radial direction to provide weight reduction and shock absorption. Has been proposed (see, for example, Patent Document 1).

  However, in this non-pneumatic tire, since the spokes 6 made of rubber or resin support the load in the tire radial direction, the shape of the spoke structure 3 is remarkably deformed, and heat is generated due to the large deformation. Since it is large, there is a problem that rolling resistance is large and fuel consumption is poor.

As countermeasures, if the number of spokes is increased or the thickness of the spokes is increased, the load bearing capacity will be improved, but the ride comfort will be lowered and the rolling resistance will still be improved due to the increase in weight. There wasn't.
JP 2005-500932 A

  An object of the present invention is to provide a non-pneumatic tire having a spoke structure that improves load bearing capacity and rolling resistance without increasing weight.

  In order to achieve the above object, a non-pneumatic tire of the present invention is a non-pneumatic tire in which an annular outer peripheral member and an inner peripheral member are connected by spokes, and at least the spoke has a spoke structure made of rubber or resin. In the tire, a metal layer is attached to at least a radial surface of the spoke.

  The non-pneumatic tire of the present invention has a spoke structure in which at least the spoke is formed of rubber or resin, and the metal layer is attached to at least the radial surface of the spoke. While increasing the rigidity in the radial direction to improve the load supporting ability and suppressing the deformation at the time of tire rotation with the improvement of the load supporting ability, it is possible to reduce heat generation and reduce rolling resistance. Moreover, since the metal layer may be thin, the tire weight does not increase.

  FIG. 1 shows an embodiment of the non-pneumatic tire of the present invention. The non-pneumatic tire is configured by joining the spoke structure 3 to the inner peripheral side of the tread ring 1 and further joining the base portion 2 to the inner peripheral side thereof. The spoke structure 3 is configured by connecting an annular outer peripheral member 4 and an inner peripheral member 5 with a plurality of radial spokes 6. The spoke structure 3 is integrally formed of rubber or resin, and a metal layer 8 is formed on a wall surface (surface extending in the tire width direction) facing the tire circumferential direction of the radial surface 7 of the spoke 6. Is affixed with an adhesive or the like.

  In the non-pneumatic tire, even if the spoke 6 is formed of rubber or resin, the metal layer 8 having excellent rigidity is attached to the wall surface forming the radial surface 7 of the spoke 6. The load supporting ability of the spoke 6 is improved by the combined action of 8. Moreover, since the excessive deformation | transformation of the spoke 6 is suppressed by the improvement of the load support capability of the spoke 6, rolling resistance can be reduced by reducing the emitted-heat amount.

  The spoke structure has a configuration in which a plurality of spokes are connected in a radial direction between an annular outer peripheral member and an inner peripheral member, and at least the spoke is formed of rubber or resin. The inner peripheral member may be another material such as a metal. In addition, if the spoke connects between the annular outer peripheral member and the inner peripheral member, the direction extending in the radial direction is the direction inclined with respect to the normal even if the direction is the normal direction. Alternatively, it may be curved or refracted. Similarly, the direction extending in the width direction or the circumferential direction may be parallel to the width direction or the circumferential direction, may be inclined with respect to these directions, or may be curved or refracted.

  The form of the spoke is not particularly limited, and examples thereof include fins, blades, cylinders, plate-like pairs having curved surfaces or bent surfaces, and combinations thereof. Can do. In addition, a plurality of through holes having a circular shape, an elliptical shape, a triangular shape, a quadrangular shape, or other polygonal shapes are formed at intervals on the side surface in the width direction end portion of the annular spoke structure, and the outer peripheral surface in the radial direction May be the outer peripheral member, the inner peripheral surface may be the inner peripheral member, and the radial connecting portion may be the spoke.

  The direction of the radial surface of the spoke may be facing the tire circumferential direction, facing the width direction, or facing in any direction. That is, it may be parallel to the equator plane, perpendicular to it, or intermediate between them. Further, depending on the form of the spoke, such as a cylindrical shape or a curved or bent shape, the orientation of the surface may change depending on the position in the tire radial direction.

  In this invention, it is preferable that the radial direction surface which affixes a metal layer is a wide area side among the radial direction surfaces of a spoke. This is because the effect of increasing the spring stiffness in the radial direction of the spoke is easily obtained. 2A to 2C show other examples of spokes to which the metal layer is attached in this way.

  In FIG. 2 (A), the spoke 6 is configured in a cylindrical shape so that the larger side of the radial surface extends in the tire width direction, and the metal layer 8 is provided on the surface 7 substantially perpendicular to the equatorial plane of the spoke 6. It is pasted. In FIG. 2 (B), the spoke 6 is configured such that the radial surface on the wide area side becomes the inner peripheral surface of a plurality of rhombus-shaped through holes provided in the tire width direction. In FIG. 2C, the wide area side is configured to be the inner peripheral surface of a plurality of trapezoidal through holes in the tire width direction. 2B and 2C, the metal layer 8 is attached to the radial surface 7 on the wide area side.

  On the other hand, FIGS. 3A and 3B show the case where the radial surface 7 on the wide area side of the spoke 6 extends in the tire circumferential direction, and the metal layer 8 is attached to the surface. . In FIG. 3 (A), the spoke 6 extends in the tire circumferential direction like an H-shaped steel, and in FIG. 3 (B), two spokes extend in the tire circumferential direction at both ends in the tire width direction. 6 is formed substantially parallel to the equator plane.

  In the present invention, the metal layer is preferably attached to the entire surface as shown in FIG. 1 on the wide area side of the radial surface of the spoke, but only a part as in the examples of FIG. 2, FIG. 3 and FIG. You may affix only to. For example, FIG. 2 and FIG. 3 show the case where the metal layer 8 is arranged in a substantially central region in the radial direction of the radial surface 7 of the spoke 6, and FIGS. 4 (A) to (C) are radial directions of the spoke 6. This is a case where the metal layer 8 is arranged so as to be divided into regions near the outer peripheral member and the inner peripheral member in the surface 7. Moreover, you may arrange | position a metal layer only to the area | region close to either an outer peripheral member or an inner peripheral member. Also in the example of FIG. 3, the region in which the metal layer is disposed may be reversed between the radial central region and the outer region and / or the inner region. Moreover, you may arrange | position on the front and back both surfaces of a spoke, and may affix only on either one.

  Furthermore, it is also preferable to provide the metal layer so as to extend to the inner peripheral surface of the outer peripheral member and / or the outer peripheral surface of the inner peripheral member. By sticking the metal layer over the inner peripheral surface of the outer peripheral member and the outer peripheral surface of the inner peripheral member, the end of the metal layer can be disposed in a region where deformation is small, thereby preventing peeling from the end. it can. In addition, by continuously attaching a metal layer from the radial surface of the spoke to the inner peripheral surface of the outer peripheral member and / or from the radial surface of the spoke to the outer peripheral surface of the inner peripheral member, the load supporting ability is further improved and the deflection is achieved. The amount can be reduced and the rolling resistance can be reduced.

  For example, in the spoke structure of FIG. 2C, the radial surface 7 facing between the adjacent spokes 6, the inner peripheral surface of the outer peripheral member connecting them and the entire outer peripheral surface of the inner peripheral member, that is, a trapezoid. A metal layer may be continuously pasted over the entire inner peripheral surface of the through-hole, or a metal layer may be pasted intermittently on a part thereof so as to satisfy the configuration of the present invention. When affixing a metal layer over the entire inner peripheral surface of the trapezoidal through-hole, the metal layer may be seamless, joined by striking, or joined so that parts of them overlap. May be. Further, such an embodiment can be applied to FIGS. 2A and 2B other than FIG. 2C or other spoke shapes, and the same effect can be obtained. .

  In the present invention, the area where the metal layer is attached is preferably 10% or more, more preferably 30% or more, and 100% at the maximum with respect to the radial surface of one spoke. Further, the ratio of the spokes to the radial length is preferably 10% or more, more preferably 30% or more, and a maximum of 100%. When the ratio of the area of the metal layer to the radial surface of the spoke is 10% or more, or the radial length is 10% or more, the effect of the present invention can be achieved. Moreover, when a metal layer is affixed on both front and back surfaces of a spoke or when a metal layer is separated and arranged, the area and the radial length of the radial surface of the metal layer are the total.

  Here, the radial length of the spoke is the distance between the inner peripheral surface of the outer peripheral member and the outer peripheral surface of the inner peripheral member and the intersection of the normal line, that is, the radius of the inner peripheral surface of the outer peripheral member and the outer periphery of the inner peripheral member. The difference from the radius of the surface. Further, the area of the radial surface of the spoke is an area obtained by integrating the radial length of the spoke in the tire width direction or the tire circumferential direction, that is, in the direction in which the radial surface extends. Therefore, when the spoke radial surface extends in the tire circumferential direction, the spoke radial surface area is the area projected on the tire equatorial plane, while the spoke radial surface is in the tire width direction. When extending, the area of the spoke radial surface is the area projected on the tire meridian section.

  The length in the radial direction of the metal layer is the length on the normal line, and when not on the normal line, the length on the normal line when the metal layer is rotated around the tire rotation axis and projected onto the normal line. To do. The area of the radial surface of the metal layer is obtained by integrating the radial length of the metal layer in the tire width direction or the tire circumferential direction, that is, in the same extension direction as the radial surface of the spoke to which the metal layer belongs. The area.

  Although the thickness of a metal layer is not specifically limited, Preferably it is 0.005-1.0 mm, More preferably, it is 0.005-0.30 mm. If the thickness of the metal layer is less than 0.005 mm, the effect of improving the rigidity may not be sufficiently obtained, and if it exceeds 1.0 mm, the weight increase is undesirably increased. Further, within the above range, when the thickness of the metal layer is relatively thin, the effect of mainly reinforcing the rigidity of the spoke constituted by rubber or resin is obtained, and when the thickness of the metal layer is relatively thick, The elastic effect of the metal layer itself, particularly the elastic recovery action is mainly obtained, and any case is preferable.

  The method for attaching the metal layer to the radial surface of the spoke is not particularly limited, but any method can be used. For example, a metal thin plate may be attached to the surface of the spoke in the radial direction via an adhesive, or the metal thin plate may be insert-molded when the spoke is formed. Furthermore, after disposing the metal layer on the surface of the spoke in the radial direction, a material for rust prevention may be applied to the surface of the metal layer, or a thin layer of rubber or resin may be laminated.

  In this invention, it is preferable that the metal material which comprises a metal layer has as a main component any one chosen from iron, copper, zinc, and aluminum, and may be a single material or an alloy. In particular, iron or stainless steel is more preferable, and the rigidity improvement effect is excellent. In particular, stainless steel is preferable because of its high rigidity and excellent durability.

  The outer peripheral member and the inner peripheral member are not particularly limited as long as they are elastic materials, but are preferably composed of rubber or resin, rubber or resin coated with a cord reinforcing material, and more preferably rubber or resin. preferable. The materials constituting the outer peripheral member and the inner peripheral member may be the same or different.

  A non-pneumatic tire having an outer diameter, width, and inner diameter corresponding to a tire size of 195 / 65R15 of a pneumatic tire is made cylindrical with spokes as shown in FIG. 2 (A), and the outer member and inner member are made of polyurethane. Three types (Examples 1 and 2 and conventional examples) in which the metal layers are configured differently as shown in Table 1 were formed under common conditions. The ratio between the area of the metal layer and the length in the radial direction was determined by the following method.

  The obtained three types of non-pneumatic tires were measured for deflection amount and rolling resistance by the following methods, and the results are shown in Table 1.

[Ratio of metal layer area and radial length]
The ratio of the area of the metal layer was expressed as a percentage of the area of the metal layer with respect to the area of the inner peripheral surface extending in the tire width direction of the cylindrical spoke as 100. The ratio of the radial length of the metal layer is expressed as a percentage of the length projected on the tire equatorial plane of the metal layer with respect to the length of the cylindrical spoke projected on the tire equatorial plane. did.

[Deflection]
A non-pneumatic tire was assembled on a rim corresponding to a rim size of 15 inches of a pneumatic tire, a load of 4 kN was applied to the axle mounting portion of the rim, and the amount of deflection of the tread tread inward in the tire radial direction was measured. The obtained results are shown as an index with the conventional example as 100. The smaller this value, the smaller the deflection and the better.

[Rolling resistance]
The resistance force of the non-pneumatic tire was measured using a drum testing machine having a drum diameter of 1700 mm under the conditions of a load of 4 kN and a speed of 80 km / h. The evaluation results are shown as an index with the conventional example as 100. The smaller this value, the less rolling resistance and the better.

It is a perspective view showing an example of the non-pneumatic tire of the present invention. (A)-(C) It is a perspective view which shows the other example of the non-pneumatic tire of this invention as a partial cross section. (A) (B) It is a perspective view which shows the other example of the non-pneumatic tire of this invention as a partial cross section. (A)-(C) It is a perspective view which shows the further another example of the non-pneumatic tire of this invention as a partial cross section. It is a perspective view which shows the state which mounted | wore the non-pneumatic tire to the wheel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tread ring 3 Spoke structure 4 Outer peripheral member 5 Inner peripheral member 6 Spoke 7 Radial surface 8 Metal layer

Claims (6)

In a non-pneumatic tire having a spoke structure in which an annular outer peripheral member and an inner peripheral member are connected with spokes, and at least the spoke is made of rubber or resin,
A non-pneumatic tire in which a metal layer is attached to at least the radial surface of the spoke.   The non-pneumatic tire according to claim 1, wherein a ratio of the metal layer to a radial surface of the spoke is 10% or more.   The non-pneumatic tire according to claim 2, wherein a ratio of the metal layer to a radial length of the spoke is 10% or more.   The non-pneumatic tire according to claim 1, 2 or 3, wherein the metal layer is provided so as to extend to an inner peripheral surface of the outer peripheral member and / or an outer peripheral surface of the inner peripheral member.   The non-pneumatic tire according to any one of claims 1 to 4, wherein the metal layer has a thickness of 0.005 to 1.0 mm.   The non-pneumatic tire according to any one of claims 1 to 5, wherein the metal layer is made of a metal material mainly composed of iron, copper, zinc, or aluminum.

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