JP2014094699A - Non-pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-pneumatic tire that can reduce a peak level of noise, and can disperse a peak frequency.SOLUTION: A non-pneumatic tire T has a support structure SS including: an inside annular part 1; an outside annular part 2 concentrically provided outside the inside annular part 1; and a plurality of connection parts 3 connecting the inside annular part 1 with the outside annular part 2, and each provided in the tire circumferential direction CD, independently. In the non-pneumatic tire, the support structure SS is equally divided into n pieces of blocks (n is an integer of 2 or more) in the tire circumferential direction CD, and the n pieces of blocks are made up of the blocks of at least two kinds or more made different from each other in thickness tk in the tire circumferential direction of the connection part 3 included in each block or in interval Lk between the connection parts.

Description

  The present invention relates to a non-pneumatic tire provided with a support structure that supports a load from a vehicle as a tire structural member, and preferably a non-pneumatic tire that can be used as a substitute for a pneumatic tire. It relates to tires.

  The pneumatic tire has a load supporting function, a shock absorbing ability from the ground contact surface, and a transmission ability (acceleration, stop, change of direction) such as power. For this reason, many vehicles, particularly bicycles, motorcycles, automobiles, It is used in trucks.

  In particular, these capabilities greatly contributed to the development of automobiles and other motor vehicles. Furthermore, the impact absorbing ability of pneumatic tires is useful for medical equipment and electronic equipment transport carts and other applications.

  Conventional non-pneumatic tires include, for example, solid tires, spring tires, cushion tires, and the like, but do not have the superior performance of pneumatic tires. For example, solid tires and cushion tires having a solid rubber structure support a load by compressing the contact portion, but this type of tire is heavy and stiff, and does not have a shock absorbing ability like a pneumatic tire. Therefore, solid tires and cushion tires have not been adopted for passenger cars where ride comfort performance is important.

  The following Patent Document 1 includes a reinforcing annular band that supports a load applied to a tire, and a plurality of web spokes that transmit a load force by tension between the reinforcing annular band and a wheel or a hub. And non-pneumatic tires with improved durability.

  Patent Document 2 below discloses a plurality of spoke structures in the tire width direction in which fins that are radially connected between an annular outer peripheral member and an inner peripheral member are intermittently arranged in the circumferential direction. And a non-pneumatic tire in which fin positions are shifted from each other in the circumferential direction between adjacent bands.

  In the non-pneumatic tire of Patent Document 1, it is estimated that the distance between web spokes is substantially constant. Further, even in the non-pneumatic tire of Patent Document 2, it is estimated that the interval between the fins is substantially constant in each band. As described above, when web spokes or fins having the same shape are provided at equal intervals along the tire circumferential direction, a striking sound is generated at a constant period during tire rolling, and noise of the order component is generated. Since noise is not generated much at frequencies other than the order component, the noise becomes conspicuous as a result.

Special Table 2005-500932 Publication JP 2008-55928 A

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a non-pneumatic tire that can reduce the peak level of noise and disperse the peak frequency.

The above object can be achieved by the present invention as described below.
That is, the non-pneumatic tire of the present invention connects the inner annular portion, the outer annular portion concentrically provided outside the inner annular portion, the inner annular portion and the outer annular portion, and the tire circumferential direction. A non-pneumatic tire having a support structure including a plurality of connecting portions provided independently of each other,
The support structure is equally divided into n blocks (n is an integer of 2 or more) in the tire circumferential direction,
The n blocks are composed of at least two or more types of blocks in which the thickness in the tire circumferential direction of the connecting portion included in each block or the interval between the connecting portions is different from each other.

  The non-pneumatic tire of the present invention connects an inner annular portion, an outer annular portion concentrically provided outside the inner annular portion, an inner annular portion and an outer annular portion, and is independent of each other in the tire circumferential direction. And a plurality of connecting portions provided. The support structure is equally divided into n blocks in the tire circumferential direction, and each block includes a connecting portion. The n blocks are composed of at least two types of blocks in which the tire circumferential thickness of the connecting portions included in each block or the interval between the connecting portions are different from each other, so that a constant cycle is always provided during tire rolling. Thus, no damage is generated by the connecting portion, and the energy generated by hitting the connecting portion is used to generate noise of various frequencies. As a result, the non-pneumatic tire of the present invention has a noise peak compared to the case where the hitting by the connecting portion occurs at a constant period and the energy by hitting the connecting portion is used to generate noise of a specific frequency. The level can be lowered. In addition, since the non-pneumatic tire of the present invention generates noise of various frequencies, the peak frequency of noise can be dispersed, and the noise is less noticeable.

  In the non-pneumatic tire according to the present invention, the total thickness obtained by totaling the tire circumferential direction thicknesses of the connecting portions included in each block is ± (average of the minimum total thickness and the maximum total thickness among all blocks. It is preferably within n × 2)%. By setting the connection part included in each block in this way, the rigidity difference and mass difference between the blocks are reduced, so that the rigidity in the tire circumferential direction is made substantially uniform and the uniformity is kept in good condition. The peak level can be lowered and the peak frequency can be dispersed.

  In the non-pneumatic tire according to the present invention, the total thickness of the arbitrary blocks is within ± n% of the average value of the total thickness of the arbitrary blocks and the total thickness of the facing blocks facing each other across the tire shaft. Preferably there is. According to this configuration, the difference in rigidity and mass between blocks facing each other across the tire shaft is reduced, so that the peak level of noise is reduced and the peak frequency is dispersed while maintaining good tire uniformity. Can be made.

  In the non-pneumatic tire according to the present invention, the number of connecting portions included in each block is preferably less than twice the value obtained by dividing the total number of connecting portions of the entire tire by n. According to this configuration, the rigidity difference and mass difference between the blocks are reduced, so that the tire circumferential direction rigidity is made substantially uniform, the uniformity is kept good, the noise peak level is lowered, and the peak frequency is reduced. Can be dispersed.

  In the non-pneumatic tire according to the present invention, it is preferable that the tire circumferential thickness of the connecting portion is the same in each block. Moreover, in the non-pneumatic tire according to the present invention, it is preferable that the plurality of connecting portions included in each block are arranged at equal intervals. According to these configurations, the rigidity is uniform in each block, so that the rigidity in the tire circumferential direction is substantially uniform, the noise level is reduced and the peak frequency is dispersed while maintaining good uniformity. Can be made.

Front view showing an example of the non-pneumatic tire of the present invention The front view which shows an example of the arbitrary blocks which comprise a support structure The front view which shows an example of the arbitrary blocks which comprise a support structure Front view showing a non-pneumatic tire according to another embodiment Side view showing a non-pneumatic tire according to another embodiment

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the configuration of the non-pneumatic tire T of the present invention will be described. FIG. 1 is a front view showing an example of a non-pneumatic tire. Here, O indicates a tire shaft, and H indicates a tire cross-sectional height.

  The non-pneumatic tire T of the present invention has a support structure SS that supports a load from a vehicle. The non-pneumatic tire T of the present invention only needs to be provided with such a support structure SS, and a member corresponding to a tread on the outer side (outer peripheral side) or inner side (inner peripheral side) of the support structure SS, A reinforcing layer, a member for fitting with an axle or a rim, and the like may be provided.

  As shown in the front view of FIG. 1, the non-pneumatic tire T of the present embodiment includes an inner annular portion 1, an outer annular portion 2 provided concentrically on the outer side, and an inner annular portion. 1 and the outer annular portion 2 are connected, and a plurality of connecting portions 3 provided independently in the tire circumferential direction CD are provided.

  The support structure SS is equally divided into n (n is an integer of 2 or more) blocks B1, B2,..., Bn in the tire circumferential direction CD. That is, the support structure SS is composed of two or more blocks. In addition, 4-40 are preferable and, as for the number n of blocks, 8-30 are more preferable. When the number of blocks n is less than 4, the peak frequency cannot be effectively dispersed. When the number of blocks n is more than 40, the circumferential length of the blocks is shortened. When the connecting portion 3 is bent, it easily contacts itself. In the present embodiment, an example in which the support structure SS is divided into four blocks B1, B2, B3, and B4 is shown.

  The inner annular portion 1 is preferably a cylindrical shape having a constant thickness from the viewpoint of improving uniformity. Moreover, it is preferable to provide the inner peripheral surface of the inner annular portion 1 with irregularities or the like for maintaining fitting properties for mounting with an axle or a rim.

  The thickness of the inner annular portion 1 is preferably 1 to 20% of the tire cross-section height H and more preferably 2 to 10% from the viewpoint of reducing weight and improving durability while sufficiently transmitting force to the connecting portion 3. preferable.

  The inner diameter of the inner annular portion 1 is appropriately determined in accordance with the rim on which the non-pneumatic tire T is mounted and the dimensions of the axle. However, when an alternative to a general pneumatic tire is assumed, 250 to 500 mm is preferable, and 330 to 440 mm is more preferable.

  The width of the inner annular portion 1 in the tire axial direction is appropriately determined according to the application, the length of the axle, and the like. However, when an alternative to a general pneumatic tire is assumed, 100 to 300 mm is preferable, and 130 to 250 mm is preferable. More preferred.

  The tensile modulus of the inner annular portion 1 is preferably 5 to 180000 MPa, more preferably 7 to 50000 MPa, from the viewpoint of reducing weight, improving durability, and wearing properties while sufficiently transmitting force to the connecting portion 3. The tensile modulus in the present invention is a value calculated from a tensile stress at 10% elongation by conducting a tensile test according to JIS K7312.

  The support structure SS in the present invention is formed of an elastic material. However, the inner ring portion 1, the outer ring portion 2, and the connection portion 3 are used from the viewpoint of enabling integral molding when the support structure SS is manufactured. Are preferably basically the same material except for the reinforcing structure.

  The elastic material in the present invention refers to a material having a tensile modulus calculated from a tensile stress at 10% elongation by a tensile test according to JIS K7312 and 100 MPa or less. The elastic material of the present invention preferably has a tensile modulus of 5 to 100 MPa, more preferably 7 to 50 MPa from the viewpoint of imparting adequate rigidity while obtaining sufficient durability. Examples of the elastic material used as the base material include thermoplastic elastomers, crosslinked rubbers, and other resins.

  Examples of the thermoplastic elastomer include polyester elastomer, polyolefin elastomer, polyamide elastomer, polystyrene elastomer, polyvinyl chloride elastomer, polyurethane elastomer and the like. Rubber materials constituting the crosslinked rubber material include natural rubber, styrene butadiene rubber (SBR), butadiene rubber (BR), isoprene rubber (IIR), nitrile rubber (NBR), hydrogenated nitrile rubber (hydrogenated NBR). And synthetic rubbers such as chloroprene rubber (CR), ethylene propylene rubber (EPDM), fluorine rubber, silicon rubber, acrylic rubber, and urethane rubber. These rubber materials may be used in combination of two or more as required.

  Examples of other resins include thermoplastic resins and thermosetting resins. Examples of the thermoplastic resin include polyethylene resin, polystyrene resin, and polyvinyl chloride resin, and examples of the thermosetting resin include epoxy resin, phenol resin, polyurethane resin, silicon resin, polyimide resin, and melamine resin.

  Of the above elastic materials, a polyurethane resin is preferably used from the viewpoint of moldability / workability and cost. In addition, as an elastic material, you may use a foaming material, and what used said thermoplastic elastomer, crosslinked rubber, and other resin foamed can be used.

  In the support structure SS integrally formed of an elastic material, the inner annular portion 1, the outer annular portion 2, and the connecting portion 3 are preferably reinforced by reinforcing fibers.

  Examples of the reinforcing fibers include reinforcing fibers such as long fibers, short fibers, woven fabrics, and non-woven fabrics. As a form using long fibers, fibers arranged in the tire axial direction and fibers arranged in the tire circumferential direction It is preferable to use a net-like fiber assembly composed of:

  Examples of the types of reinforcing fibers include rayon cords, polyamide cords such as nylon-6,6, polyester cords such as polyethylene terephthalate, aramid cords, glass fiber cords, carbon fibers, and steel cords.

  In the present invention, in addition to reinforcement using reinforcing fibers, it is possible to perform reinforcement with a granular filler or reinforcement with a metal ring or the like. Examples of the particulate filler include ceramics such as carbon black, silica, and alumina, and other inorganic fillers.

  The shape of the outer annular portion 2 is preferably a cylindrical shape with a constant thickness from the viewpoint of improving uniformity. The thickness of the outer annular portion 2 is preferably 1 to 20% of the tire cross-section height H, and preferably 2 to 10% from the viewpoint of reducing weight and improving durability while sufficiently transmitting the force from the connecting portion 3. More preferred.

  The inner diameter of the outer annular portion 2 is appropriately determined according to its use. However, when an alternative to a general pneumatic tire is assumed, 420 to 750 mm is preferable, and 480 to 680 mm is more preferable.

  Although the width | variety of the tire axial direction of the outer side annular part 2 is suitably determined according to a use etc., when substitution of a general pneumatic tire is assumed, 100-300 mm is preferable and 130-250 mm is more preferable.

  The tensile modulus of the outer annular portion 2 can be set to the same level as that of the inner annular portion 1 when the reinforcing layer 7 is provided on the outer periphery of the outer annular portion 2 as shown in FIG. In the case where such a reinforcing layer 7 is not provided, 5 to 180000 MPa is preferable, and 7 to 50000 MPa is more preferable from the viewpoint of reducing weight and improving durability while sufficiently transmitting the force from the connecting portion 3.

  When the tensile modulus of the outer annular portion 2 is increased, a fiber reinforced material obtained by reinforcing an elastic material with fibers or the like is preferable. By reinforcing the outer annular portion 2 with the reinforcing fiber, adhesion between the outer annular portion 2 and the belt layer becomes sufficient.

  The connecting portion 3 connects the inner annular portion 1 and the outer annular portion 2, and a plurality of connecting portions 3 are provided so as to be independent from each other in the tire circumferential direction CD with an appropriate interval therebetween.

  2 and 3 show an example of an arbitrary block Bk constituting the support structure SS (where 1 ≦ k ≦ n). Each block includes at least one connecting portion 3. This block Bk includes four connecting portions 3. Further, the number of connecting portions 3 included in each block is less than twice the value obtained by dividing the total number of connecting portions 3 of the entire tire by n. 1-20 pieces are preferable and, as for the number of the connection parts 3 contained in each block, 1-15 pieces are more preferable.

  As shown in FIG. 2, the thickness at the portion where the connecting portion 3 is connected to the inner peripheral portion 2a of the outer annular portion 2 is defined as the tire circumferential direction thickness tk of the connecting portion 3 included in the block Bk. In this invention, it is preferable that the tire circumferential direction thickness of the connection part 3 is the same all within each block. In the example of FIG. 2, the tire circumferential direction thickness tk of all the connection parts 3 in the block Bk is equal.

  As shown in FIG. 3, the length along the tire circumferential direction between the points 3 a where the centers of the adjacent connecting portions 3 intersect with the inner peripheral portion 2 a of the outer annular portion 2 is expressed as an interval Lk between the connecting portions 3. Determine. In this invention, it is preferable that the some connection part 3 contained in each block is arrange | positioned at equal intervals. In the example of FIG. 3, the intervals Lk between all the connecting portions 3 are equal. The space | interval Lk between the connection parts 3 is 10-50 mm, for example. Moreover, it is preferable that the tire circumferential direction thickness tk of the connection part 3 shall be 10% or more and 50% or less of the space | interval Lk between the connection parts 3. FIG.

  Furthermore, it is preferable that the distance from the both ends in the tire circumferential direction of the block Bk to the nearest connecting portion 3 is half of the interval Lk between the connecting portions 3. Thereby, the some connection part 3 is arrange | positioned with sufficient balance in the block Bk. At this time, the interval Lk is a value obtained by dividing the length in the tire circumferential direction of the inner peripheral portion 2a of the outer annular portion 2 in the block Bk by the number of connecting portions 3 included in the block Bk (4 in this example). .

  In the present invention, n blocks B1, B2,..., Bn have at least two or more types of blocks in which the thickness in the tire circumferential direction of the connecting portion 3 included in each block or the interval between the connecting portions 3 is different from each other. It consists of The type of block is (number of blocks n / 2) +1 or less. When there are too many types of blocks with respect to the number of blocks, the manufacturing cost increases, so 10 or less types are preferable. In the present embodiment, the four blocks B1 to B4 are configured by three types of blocks as described later.

  In the block B1 shown in FIG. 1, twelve connecting portions 3 having a tire circumferential direction thickness t1 are included at equal intervals with an interval L1. The block B2 includes eight connecting portions 3 having a tire circumferential direction thickness t2 at equal intervals with an interval L2. The block B3 includes twelve connecting portions 3 having a tire circumferential direction thickness t3 at regular intervals with an interval L3. The block B4 includes ten connecting portions 3 having a tire circumferential thickness t4 at an interval L4.

  In the present embodiment, the tire circumferential thickness t1, the tire circumferential thickness t2, and the tire circumferential thickness t4 are different from each other, and the tire circumferential thickness t1 and the tire circumferential thickness t3 are equal. That is, the blocks B1, B2, B3, and B4 are composed of three types of blocks in which the thicknesses in the tire circumferential direction of the connecting portion 3 included in each block are different from each other.

  In the present embodiment, the interval L1, the interval L2, and the interval L4 are different from each other, and the interval L1 and the interval L3 are equal. That is, the blocks B1, B2, B3, and B4 are configured by three types of blocks in which the intervals between the connecting portions 3 of the connecting portions 3 included in each block are different from each other.

  Thus, in this embodiment, the four blocks B1 to B4 are configured by three types of blocks in which the tire circumferential thickness included in each block and the interval between the connecting portions 3 are different from each other. As a result, energy generated by striking the connecting portion 3 during rolling of the tire is used to generate noise having various frequencies, so that the peak level of noise can be reduced and the peak frequency of noise can be dispersed.

  In the present invention, the total thickness obtained by summing the tire circumferential direction thicknesses of the connecting portions 3 included in each block is ± (n × 2) of the average value of the minimum total thickness and the maximum total thickness among all the blocks. % Is preferable. By setting the connecting portion 3 included in each block in this way, the rigidity difference and mass difference between the blocks are reduced, so that the rigidity in the tire circumferential direction CD is substantially uniform, and the uniformity is kept good, The peak level of noise can be reduced and the peak frequency can be dispersed.

  In the embodiment of FIG. 1, the total thickness T1 (= t1 × 12) of the tire circumferential direction thickness t1 of the connecting portion 3 included in the block B1 is T1, and the tire circumferential direction thickness t2 of the connecting portion 3 included in the block B2 is The total thickness is T2 (= t2 × 8), the total thickness t3 of the connecting portions 3 included in the block B3 is T3 (= t3 × 12), and the total thickness of the connecting portions 3 included in the block B4. The total thickness of the tire circumferential direction thickness t4 is T4 (= t4 × 10). At this time, for example, the total thickness T1 is within ± 8 (= 4 × 2)% of the average value of the minimum total thickness among the total thicknesses T1 to T4 and the maximum total thickness among the total thicknesses T1 to T4. Is set as follows. The total thicknesses T2, T3, and T4 are set similarly.

  In the present invention, the total thickness of the arbitrary block is within ± n% of the average value of the total thickness of the arbitrary block and the total thickness of the facing blocks facing each other across the tire axis O. Is preferred. For example, in the embodiment of FIG. 1, the total thickness T1 of the block B1 is ± 4% of the average value of the total thickness T1 of the block B1 and the total thickness T3 of the block B3 facing each other across the block B1 and the tire axis O. It is set to be within. The total thicknesses T2, T3, and T4 are set similarly.

  When the number of blocks n is an odd number, there are two blocks that face each other across the tire axis O. At this time, the total thickness of the facing block is obtained as an average value of the total thickness of the two blocks facing the arbitrary block with the tire axial direction interposed therebetween. FIG. 4 shows an example in which the number of blocks n is 5. In this example, the support structure SS is composed of three types of blocks, and the blocks B1, B3, and B4 have different shapes, the blocks B1 and B2 have the same shape, and the blocks B3 and B5 have the same shape. It has become. When the number of blocks n is 5, there are two blocks B3 and B4 that face each other across the block B1 and the tire axis O. The total thickness of the facing blocks facing each other across the block B1 and the tire axis O is obtained by an average value of the total thickness T3 of the block B3 and the total thickness T4 of the block B4.

  The number of connecting portions 3 of the entire tire is preferably 10 to 80, and 40 to 60 from the viewpoint of reducing weight, improving power transmission, and improving durability while sufficiently supporting the load from the vehicle. More preferred.

  Examples of the shape of each connecting portion 3 include a plate-like body and a columnar body, and the cross-sectional shape of the connecting portion 3 is rectangular. These connecting portions 3 extend in the radial direction or in a direction inclined from the radial direction in the front sectional view. In the present invention, in the front sectional view, the extending direction of the connecting portion 3 is preferably within ± 25 ° in the radial direction, more preferably within ± 15 ° in the radial direction, and most preferably in the radial direction.

  The thickness of the connecting portion 3 in the tire circumferential direction is 1 to 30% of the tire cross-section height H from the viewpoint of reducing the weight and improving the durability while sufficiently transmitting the force from the inner annular portion 1 and the outer annular portion 2. Is preferable, and 1 to 20% is more preferable.

  The width of the connecting portion 3 in the tire axial direction is appropriately determined according to the use and the like, but is preferably 100 to 300 mm, and more preferably 130 to 250 mm when an alternative to a general pneumatic tire is assumed.

  The tensile modulus of the connecting portion 3 is preferably 5 to 50 MPa, more preferably 7 to 20 MPa from the viewpoint of reducing weight, improving durability, and improving lateral rigidity while sufficiently transmitting the force from the inner annular portion 1. .

  In this embodiment, as shown in FIG. 1, an example is shown in which a reinforcing layer 7 that reinforces bending deformation of the outer annular portion 2 is provided outside the outer annular portion 2 of the support structure SS. Moreover, in this embodiment, as shown in FIG. 1, the example in which the tread rubber 8 is provided in the further outer side of the reinforcement layer 7 is shown. As the reinforcing layer 7 and the tread rubber 8, it is possible to provide the same as the belt layer of the conventional pneumatic tire. Moreover, it is possible to provide the same pattern as a conventional pneumatic tire as a tread pattern.

[Other Embodiments]
(1) In the above-described embodiment, the example in which the cross-sectional shape of the connecting portion 3 is rectangular has been shown. However, as shown in FIG. 5, the cross-sectional shape of the connecting portion 3 can take various forms. . For example, a trapezoidal shape as shown in FIG. 5A, an oval shape as shown in FIG. 5B, a concave shape as shown in FIG. 5C, a crescent shape as shown in FIG. It can be a shape. In the case of the concave shape shown in FIG. 5C, the thickness of the central portion in the tire axial direction is preferably 10% or more of both end portions. In the case of the crescent moon shown in FIG. 5 (d), the thickness of both end portions in the tire width direction is preferably 10% or more of the central portion.

  (2) As another embodiment of the present invention, the inner annular portion 1, the intermediate annular portion provided concentrically outside the inner annular portion 1, and the concentric circle provided outside the intermediate annular portion The outer annular part 2, the inner annular part 1 and the intermediate annular part are connected, and a plurality of inner connecting parts provided independently in the tire circumferential direction CD, and the outer annular part 2 and the intermediate annular part are connected. In the non-pneumatic tire having a support structure including a plurality of outer connecting portions provided independently in the tire circumferential direction CD, the number of the support structures is n in the tire circumferential direction CD (n is 2 or more). (Integer) blocks, and n blocks are composed of at least two or more types of blocks in which the outer circumferential portion included in each block has different thickness in the tire circumferential direction or different intervals between the outer coupling portions. It may be what is done. That is, in the present invention, for the plurality of outer connecting portions connected to the outer annular portion 2, the tire circumferential thickness or the interval between the connecting portions may be different between the blocks, and the plurality of inner connecting portions are shaped, The number, arrangement, etc. are not particularly limited.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below.

  Each example was analyzed and noise for each frequency was calculated. The analysis method was to calculate the impact generated when the place where the connecting portion was in contact with the ground during rolling of the tire, and frequency analysis was performed. The evaluation method focused on the frequency region where noise was generated in the comparative example, and examined the maximum level of noise.

Example 1
Inner ring (corresponding to the inner annular part), intermediate ring (corresponding to the intermediate annular part), outer ring (corresponding to the outer annular part), inner spoke (corresponding to the inner connecting part) in the dimensions and physical properties shown in Table 1 A non-pneumatic tire including a support structure provided with outer spokes (corresponding to an outer connecting portion), three reinforcing layers provided on the outer periphery thereof, and tread rubber was evaluated. The number of blocks was 15, and the types of blocks were three. The inner and outer spokes have the same shape and are provided at the same position in the tire circumferential direction. The evaluation results are also shown in Table 1.

Example 2
Non-pneumatic pressure provided with inner ring, intermediate ring, outer ring, inner spoke, support structure provided with outer spoke, three layers of reinforcing layers provided on the outer periphery, and tread rubber in the dimensions and physical properties shown in Table 1 Tires were produced and the above performance was evaluated. Compared with Example 1, the difference in thickness in the tire circumferential direction between the blocks was increased. The inner and outer spokes have the same shape and are provided at the same position in the tire circumferential direction. The evaluation results are also shown in Table 1.

Example 3
Non-pneumatic pressure provided with inner ring, intermediate ring, outer ring, inner spoke, support structure provided with outer spoke, three layers of reinforcing layers provided on the outer periphery, and tread rubber in the dimensions and physical properties shown in Table 1 Tires were produced and the above performance was evaluated. Compared with Example 1, the difference in thickness in the tire circumferential direction between the blocks was increased. The inner and outer spokes have the same shape and are provided at the same position in the tire circumferential direction. The evaluation results are also shown in Table 1.

Example 4
Non-pneumatic pressure provided with inner ring, intermediate ring, outer ring, inner spoke, support structure provided with outer spoke, three layers of reinforcing layers provided on the outer periphery, and tread rubber in the dimensions and physical properties shown in Table 1 Tires were produced and the above performance was evaluated. Compared with Example 1, the difference in thickness in the tire circumferential direction between the blocks was increased. The inner and outer spokes have the same shape and are provided at the same position in the tire circumferential direction. The evaluation results are also shown in Table 1.

Comparative Example 1
Non-pneumatic pressure provided with inner ring, intermediate ring, outer ring, inner spoke, support structure provided with outer spoke, three layers of reinforcing layers provided on the outer periphery, and tread rubber in the dimensions and physical properties shown in Table 1 Tires were produced and the above performance was evaluated. The plurality of outer connecting portions have a constant tire circumferential thickness and are arranged at equal intervals. The inner and outer spokes have the same shape and are provided at the same position in the tire circumferential direction. The evaluation results are also shown in Table 1.

  From the results in Table 1, the following can be understood. In the non-pneumatic tires of Examples 1 to 4, the maximum level of noise was smaller than that of Comparative Example 1. From Examples 1 to 4, it can be seen that it is better to increase the difference in thickness in the tire circumferential direction between the blocks.

DESCRIPTION OF SYMBOLS 1 Inner ring part 2 Outer ring part 3 Connection part n Block number tk Tire circumferential direction thickness Lk Space | interval of connection parts SS Support structure T Non-pneumatic tire

Claims (6)

An inner annular portion, an outer annular portion concentrically provided on the outer side of the inner annular portion, the inner annular portion and the outer annular portion are connected, and a plurality of independently provided in the tire circumferential direction. In a non-pneumatic tire having a support structure including a connecting portion,
The support structure is equally divided into n blocks (n is an integer of 2 or more) in the tire circumferential direction,
The non-pneumatic tire is characterized in that n blocks are composed of at least two or more types of blocks in which the thickness in the tire circumferential direction of the connecting portion included in each block or the interval between the connecting portions is different from each other.   Each of the total thicknesses of the tire circumferential direction thicknesses of the connecting portions included in each block is within ± (n × 2)% of the average value of the minimum total thickness and the maximum total thickness among all the blocks. The non-pneumatic tire according to claim 1.   The total thickness of the arbitrary blocks is within ± n% of the average value of the total thickness of the arbitrary blocks and the total thickness of the facing blocks facing each other across the tire shaft. Or the non-pneumatic tire of 2.   The non-pneumatic pressure according to any one of claims 1 to 3, wherein the number of connecting portions included in each block is less than twice the total number of connecting portions of the entire tire divided by n. tire.   The non-pneumatic tire according to any one of claims 1 to 4, wherein the connecting portions have the same tire circumferential thickness in each block. The non-pneumatic tire according to any one of claims 1 to 5, wherein a plurality of connecting portions included in each block are arranged at equal intervals.