JP2007112243A - Non-pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-pneumatic tire which can maintain a stable ground contact area/shape, and improves durability, ride comfort, and controllability and stability or the like by making a function of a spoke material which should exist in the clearance between outer and inner peripheral rings, a special one in the non-pneumatic tire having the outer peripheral ring and the inner peripheral ring. <P>SOLUTION: The non-pneumatic tire has the outer and inner peripheral rings made of elastic materials concentrically disposed, and the spoke materials made of elastic materials are connected to both the rings. When a compressive force in the tire radial direction is applied to the air gap between the outer and inner peripheral rings, the spoke materials are formed as a pair of the spoke materials deflecting in the direction opposite to each other in the tire circumferential direction. A connecting material made of the elastic material for suppressing the deflection to the opposite direction is provided between the pair of spoke materials. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a non-pneumatic tire, and more particularly, to a non-pneumatic tire that can maintain a stable ground contact area / ground shape and has improved durability, ride comfort, and handling stability.

  In general, non-pneumatic tires have a structure that cannot be locally deformed like pneumatic tires because rubber is solid.

  For this reason, it has been said that it is difficult for conventional non-pneumatic tires to exhibit a load bearing capacity that is as comfortable as a pneumatic tire.

For these conventional non-pneumatic tires, the function is to have the same deformation and load bearing characteristics as pneumatic tires, and these outer wheels and inner wheels are arranged concentrically. Have been proposed in which a web for connecting the webs and a large number of ribs inclined obliquely with respect to the radial surface are provided for cushioning (Patent Documents 1-5).
However, since such a non-pneumatic tire supports the tire load with a web, only the ground contact portion on the web has a high ground pressure, resulting in a small cornering force and poor steering stability. was there.

  Also, in general, these prior art products cause extreme bending deformation in response to deformation in the tire circumferential direction or increase in load due to the deep contact portion angle of the spoke connecting the inner and outer ring. Therefore, it has been difficult to obtain a stable ground contact area / ground shape due to breakage of the spoke portion due to stress concentration or a sudden change in stress transmitted from the spoke portion to the tread portion.

  Some of these prior arts have a pair of left and right webs with respect to the center of the tire width, but in order to provide a pair of left and right webs, a core is disposed for molding, etc. There is a disadvantage that manufacturing becomes difficult.

  In addition, the outer ring structure includes an elastomer shear layer, at least one first membrane adhered to the radially inner side of the elastomer shear layer, and at least one second membrane adhered to the radially outer side of the elastomer shear layer; And the ground contact portion of the tire is subjected to elastomer shear by applying an external load to the reinforced structure in which each of the first and second membranes has a longitudinal tensile elastic modulus greater than the shear elastic modulus of the shear layer. Although deformed by layer shear, each membrane maintains a substantially constant length, and the web spokes are loaded between the annular band and the hub via the tension of the web spokes that are not bonded to the ground contact portion of the tire. Non-pneumatic tires that transmit force have been proposed (Patent Document 6).

However, making the outer peripheral ring a multi-layer structure increases the weight and may cause problems such as peeling of the layer, so that it should be a simple structure if possible.
JP-A-60-236803 JP 62-295704 A JP-A-1-285403 JP-A-1-311902 Japanese Patent Laid-Open No. 2-179503 Special Table 2005-500932 Publication

  In view of the above points, the object of the present invention is to provide a special function for the spoke material that should be present in the gap between the outer ring and the inner ring in a non-pneumatic tire having an outer ring and an inner ring. Thus, it is possible to maintain a stable ground contact area and ground contact shape, and to provide a non-pneumatic tire improved in durability, ride comfort, and handling stability.

The non-pneumatic tire of the present invention that achieves the above-mentioned object has the following configuration (1).
(1) It has an outer ring and an inner ring made of an elastic material concentrically arranged, and a spoke material made of an elastic material is connected to both the wheels, and the spoke material is made of the outer circumference The pair of spokes are formed as a pair of spoke members that flex in opposite directions in the tire circumferential direction when a compressive force in the tire radial direction is applied to the gap between the wheel and the inner circumferential ring. A non-pneumatic tire characterized in that a connecting member made of an elastic material that suppresses bending in the opposite direction is provided between the members.

Further, in the non-pneumatic tire of the present invention, more preferably, the non-pneumatic tire is constituted by the following configurations (2) to (7).
(2) The non-pneumatic tire according to (1), wherein the pair of spoke members has a hollow cylindrical shape substantially having a central axis direction parallel to the tire width direction.
(3) The non-pneumatic type according to (1) above, wherein the pair of spoke members substantially forms a hollow regular polygonal shape having a central axis direction parallel to the tire width direction. tire.
(4) The pair of spoke members is provided so that the length of the spoke member is L and the minimum gap D between the adjacent pair of spoke members is D = 0.1L to 0.48L. The non-pneumatic tire as described in (2) above, wherein
(5) The non-pneumatic type described in (1), (2), (3) or (4) above, wherein 12 to 36 pairs of spoke material are formed in one tire as a whole. tire.
(6) The above-mentioned (1), (2), (3), (4), wherein the elastic material is a thermosetting resin, a thermoplastic resin or a rubber composition having a tensile modulus of 10 to 70 MPa. Or the non-pneumatic tire as described in (5).
(7) The non-pneumatic tire according to the above (1), (2), (3), (4), (5) or (6), which is a tire for a passenger car.

  According to the present invention, in a non-pneumatic tire having an outer peripheral ring and an inner peripheral ring, the function of the spoke material to be present in the gap between the outer peripheral ring and the inner peripheral ring is made special so that stable ground contact is achieved. A non-pneumatic tire with improved area, ground contact shape, and durability, ride comfort, and handling stability can be provided.

Hereinafter, the non-pneumatic tire of the present invention will be described in more detail.
The non-pneumatic tire of the present invention has an outer peripheral ring and an inner peripheral ring made of an elastic material arranged concentrically, and a spoke material made of an elastic material is connected to both the wheels, and the spoke The material is formed as a spoke material forming a pair that bends in opposite directions in the tire circumferential direction when a compressive force in the tire radial direction is applied to the gap between the outer ring and the inner ring. A connecting member made of an elastic material that suppresses bending in the opposite direction is provided between the spoke members forming the above.

  FIG. 1 is a partially enlarged schematic model side view for explaining the structure of such a non-pneumatic tire of the present invention. A non-pneumatic tire 1 has an outer peripheral ring 2 and an inner peripheral ring 3 between the two wheels. Spoke members 4, 4 'are provided in pairs in the gap. Usually, a plurality of pairs are formed.

Each of the spoke members 4 and 4 'is not particularly limited in shape, but is configured to have a semicircular arc-like curve as illustrated in FIG. 1 and illustrated in FIG. The spoke members 4 and 4 ′ are arranged such that when the compression force P in the tire radial direction is applied to the gap between the outer peripheral ring 2 and the inner peripheral ring 3 due to the semicircular arc shape, the spoke members 4, 4 ′ According to the direction, the force is divided into P ₁ and P ₂ , and as a result, the spoke members 4, 4 ′ are bent in opposite directions in the tire circumferential direction. The bending directions are indicated by arrows A and B in FIG. Spoke members 4, 4 'having such a mutual bending relationship form one pair.

  As described above, the connecting member 5 made of an elastic material is further provided between the pair of spoke members 4, 4 'that are bent in the opposite directions, as a member for suppressing the bending in the opposite direction. Since the connecting member 5 is formed across the spoke members 4 and 4 ', the bending of the spoke members 4 and 4' does not reach a certain level.

  In the description of the non-pneumatic tire according to the present invention, the above-described spoke material 4, spoke material 4 ′, and connecting material 5 have been described as members having their own functions described above. In addition, the outer peripheral ring and the inner peripheral ring may be integrally manufactured.

  Specifically, for example, as shown in FIG. 1, the spoke members 4, 4 ′ have substantially one hollow cylindrical shape, and a rectangular plate-shaped connecting member 5 is passed inside. The structure may be formed as an integral structure. In this case, it is preferable that the hollow columnar central axis direction is provided so as to be substantially parallel to the tire width direction.

  FIG. 2 is a schematic model perspective view for explaining the overall structure of the non-pneumatic tire of the present invention. In this embodiment, a total of 16 pairs of spoke members shown in FIG. A tread portion 6 is provided on the outer side and constitutes the entire tire.

  As shown in FIG. 1 and FIG. 2, for example, the number of spoke material pairs in the form of a hollow cylinder should be changed according to the size of the tire. According to knowledge, it is good to form about 12 to 36 pairs.

  In the present invention, the virtual hollow cylindrical shape has been described with reference to FIGS. 1 and 2, but it may be a polygonal shape instead of the cylindrical shape, for example, as shown in FIG. Thus, a regular octagonal shape or the like may be used. The polygonal shape may be a regular polygonal shape, but is not necessarily a regular polygonal shape. According to the knowledge of the present inventors, a regular polygonal shape is preferable, and those from a regular hexagonal columnar shape to a regular decagonal columnar shape are preferable. Further, the connecting member 5 does not have to be a single rectangular plate as shown in FIG. 1 or FIG. 2, but as shown in FIG. It may be in the form of crossing.

  Further, as shown in FIG. 4, when the pair of spoke members 4, 4 'are connected to the outer ring 2 and the inner ring 3, they may be integrally formed and connected.

  In addition, the minimum gap between adjacent pairs of spokes (the minimum gap between the outer walls of the spokes that are back to back) is a gap of a certain length so that each can bend as a spoke ( It is preferable to have a space.

  According to various knowledge of the present inventors, the hypothetical hollow cylindrical spoke material has a spoke material length of L, and the minimum gap D between adjacent pairs of spoke materials is D = 0. It is preferable to be configured so as to satisfy 1L to 0.48L.

  As shown in the conceptual model in FIG. 5 (a), the spoke material length L is the distance of the portion where the spoke material intersects the outer ring and the inner ring, and the spoke material has a curvature. In some cases, the distance is measured along the curvature. In the case of a polygonal shape, the length of the outer edge of the polygonal shape is measured. D is the minimum gap (distance) between the outer walls of the spoke members adjacent to each other back to back. In particular, a more preferable range of D is D = 0.15L to 0.35L.

  As described above, the minimum gap D between adjacent pairs of spoke members is preferably set to satisfy D = 0.1L to 0.48L, and more preferably, D = 0.15L to 0.00. By satisfying 35L, when the spoke members 4, 4 'are subjected to the compressive force load P, it is allowed to cause an appropriate bending, and the adjacent pair of spoke members is pressed by the bending. Can be satisfactorily prevented from contacting each other and supporting each other, and the outer ring and the inner ring being crushed and failing to function as a tire.

  FIG. 5 is a schematic model diagram for explaining the above-mentioned D, L, etc., FIG. 5 (a) is a schematic conceptual diagram for explaining the spoke material length L, and FIG. 5 (b) is the spoke materials 4, 4 ′ Is a schematic conceptual diagram in the case of a relatively small-diameter hollow cylindrical shape, and FIG. 5 (c) shows the spoke members 4, 4 ′ having a relatively large-diameter hollow cylindrical arc. It is the schematic conceptual diagram which showed the case where both arc-shaped spoke material 4, 4 'which forms a part and was formed in a pair in close proximity.

  The non-pneumatic tire of the present invention is not particularly limited, but in general, it is preferably a passenger tire. This is because a passenger car can predict a certain amount of applied load and can easily design an actual non-pneumatic tire according to the present invention.

  In the present invention, the outer ring and the inner ring are made of rubber, thermoplastic resin, thermosetting resin, or the like, and metal cord such as steel cord, reinforcing material such as nylon, polyester fiber cord, rayon fiber cord, etc. May be included.

  On the other hand, the elastic material constituting the spoke material and the connecting material is preferably composed of rubber, thermoplastic resin or thermosetting resin, and further, metal cord such as steel cord, nylon or polyester fiber cord, A reinforcing material such as a rayon fiber cord may be included. According to the various knowledge of the present inventors, it is preferable to use a thermosetting resin typified by urethane, for example, as the material for the spoke material and the connecting material, and further, this thermosetting resin is crosslinked. It is preferable to use as from the viewpoint of heat resistance.

  According to various studies by the present inventors, when a crosslinked thermosetting resin is used, it is preferable to use a resin having a tensile elastic modulus in the range of 10 to 70 MPa.

  Further, in the case of a tire for a normal passenger car, the dimensions of the non-pneumatic tire of the present invention are the thermosetting resin or thermoplastic resin in the range of 10 to 70 MPa in terms of the above-described tensile elastic modulus or the like. Assuming that a rubber composition is used, the outer ring has a thickness of about 1.5 cm to 4 cm, and the inner ring has a thickness larger than that of the outer ring. It may be the same or thinner, and is preferably about 0.3 cm to 2 cm.

  As described above, if it is assumed that about 12 to 36 pairs of spoke materials are used, according to the knowledge of the present inventors, the thickness of the spoke material is 0.3 cm to 2.5 cm. The thickness of the connecting material is preferably in the range of about 0.2 cm to 1.5 cm.

  In producing the non-pneumatic tire according to the present invention, an outer ring made of unvulcanized rubber, metal cord, organic fiber or the like is fitted into a mold, and a gap corresponding to the inner ring, spoke material or connecting material is inserted therein. It is also possible to insert a mold with an open metal, and then pour the resin material under pressure and heat it at the same time to heat and integrally vulcanize it, or it includes an outer ring, an inner ring and a connecting material. Spoke materials may be separately produced and bonded to be integrated.

  Therefore, the manufacturing method of the non-pneumatic tire of the present invention is not particularly limited, and various manufacturing methods can be considered.

FIG. 1 is a partially enlarged schematic model side view for explaining an example of the structure of the non-pneumatic tire of the present invention. FIG. 2 is a schematic model perspective view illustrating the entire structure of the non-pneumatic tire of the present invention. 3A and 3B are partially enlarged schematic model side views for explaining another structure of the non-pneumatic tire of the present invention. FIG. 4 is a partially enlarged schematic model side view for explaining another example of the structure of the non-pneumatic tire of the present invention. The pair of spoke members 4 and 4 ′ are connected to the outer ring 2 and the inner ring 3. It shows what is integrally made when connecting. FIG. 5 is a schematic model diagram for explaining the minimum gap D between the adjacent pair of spoke members, the spoke member length L, and the like. FIG. 5A is a schematic explanatory conceptual diagram of the spoke member length L. FIG. 5 (b) is a schematic conceptual diagram in the case where the spoke members 4, 4 ′ are in the form of a hollow cylinder having a relatively small diameter, and FIG. 5 (c) is an illustration of the spoke members 4, 4 ′. FIG. 5 is a schematic conceptual diagram when a part of a relatively large-diameter hollow cylindrical arc is formed and the arc-shaped spoke members 4, 4 ′ are paired in close proximity.

Explanation of symbols

1: Non-pneumatic tire 2: Outer ring 3: Inner ring 4, 4 ′: Spoke material 5: Connecting material 6: Tread portion P, P ₁ , P ₂ : Compression force A: Bending direction of the spoke material 4 B: Direction of deflection of spoke material 4 'D: Minimum gap between adjacent pair of spoke materials L: Length of spoke material

Claims (7)

  The outer ring and the inner ring are made of an elastic material concentrically arranged, and the spoke material made of an elastic material is connected to both the wheels, and the spoke material is made of the outer ring and the inner ring. It is formed as a pair of spokes that bend in opposite directions in the tire circumferential direction when a compression force in the tire radial direction is applied to the gap between the inner peripheral rings, and between the pair of spokes Is provided with a connecting member made of an elastic material that suppresses bending in the opposite direction.   The non-pneumatic tire according to claim 1, wherein the pair of spoke members has a hollow cylindrical shape substantially having a central axis direction parallel to the tire width direction.   The non-pneumatic tire according to claim 1, wherein the pair of spoke members substantially form a hollow regular polygonal shape having a central axis direction parallel to the tire width direction.   The pair of spoke members is provided such that the minimum gap D between the adjacent pair of spoke members is D = 0.1L to 0.48L, where the length of the spoke member is L. The non-pneumatic tire according to claim 2 characterized by the above-mentioned.   5. The non-pneumatic tire according to claim 1, wherein 12 to 36 pairs of spoke members forming a pair are formed in one whole tire.   6. The non-pneumatic tire according to claim 1, 2, 3, 4 or 5, wherein the elastic material is a thermosetting resin, a thermoplastic resin or a rubber composition having a tensile modulus of 10 to 70 MPa.   The non-pneumatic tire according to claim 1, wherein the non-pneumatic tire is a tire for a passenger car.

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