JP2016199069A - Non-pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-pneumatic tire capable of improving durability.SOLUTION: Provided is a non-pneumatic tire T comprising: an inner annular part; an outer annular part 2 disposed concentrically outside the inner annular part; and linkage parts 3 for linking the inner annular part to the outer annular part 2. The outer annular part 2 comprises: a base material part 21; and an annular layer 4 embedded inside the base material part 21 and formed of a material different from the base material part 21. In the annular layer 4, aperture sections 41 are formed penetrating the annular layer 4.SELECTED DRAWING: Figure 3

Description

  The present invention provides a non-pneumatic tire (non-) including an inner annular portion, an outer annular portion provided concentrically outside the inner annular portion, and a connecting portion that connects the inner annular portion and the outer annular portion. pneumatic tire).

  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 support the load by compressing the contact portion, but this type of tire is heavy and stiff, and does not have the ability to absorb shock like a pneumatic tire. Further, in the non-pneumatic tire, it is possible to improve the cushioning property by increasing the elasticity, but there is a problem that the load supporting ability or the durability as the pneumatic tire has is deteriorated.

  As a non-pneumatic tire, for example, in the following Patent Document 1, a circular first band, a second band that surrounds the first band in a separated state, and has a larger diameter than the first band, and the first A plurality of spokes connected between the first band and the second band and contracted or expanded by a load applied from the outside. An airless tire further including a tread connected to an outer surface of the tire and a reinforcing layer positioned between the second band and the tread is described.

  Further, in Patent Document 2 below, an inner annular portion, an outer annular portion provided concentrically outside the inner annular portion, and extending from the inner annular portion to the outer annular portion, respectively in the tire circumferential direction, A non-pneumatic tire is described that includes a plurality of independently provided connecting portions. In this non-pneumatic tire, a reinforcing layer that reinforces bending deformation of the outer annular portion is provided outside the outer annular portion, and a tread rubber is provided further outside the reinforcing layer.

  By the way, since the reinforcement layer of patent document 1 is provided for the objective of reinforcement, it is thought that it is formed with the material different from a 2nd band and a tread. Similarly, the reinforcing layer of Patent Document 2 is considered to be formed of a material different from the outer annular portion and the tread rubber. Peeling is likely to occur at the interface between such different materials, and the durability of the non-pneumatic tire can be a problem.

JP 2014-8958 A JP 2014-172404 A

  Then, the objective of this invention is providing the non-pneumatic tire which can improve durability.

The above object can be achieved by the present invention as described below.
That is, the non-pneumatic tire of the present invention includes an inner annular portion, an outer annular portion provided concentrically on the outer side of the inner annular portion, and a connecting portion that connects the inner annular portion and the outer annular portion. In the non-pneumatic tire, the outer annular portion includes a base material portion and an annular layer embedded in the base material portion and formed of a material different from that of the base material portion. Is characterized in that an opening penetrating the annular layer is formed.

  The non-pneumatic tire of the present invention includes an inner annular portion, an outer annular portion provided concentrically outside the inner annular portion, and a connecting portion that connects the inner annular portion and the outer annular portion. The outer annular part includes a base part and an annular layer embedded in the base part. However, since the base part and the annular layer are formed of different materials, the base part and the annular part are annular. Peeling tends to occur at the interface between layers. In the present invention, the opening that penetrates the annular layer is formed in the annular layer, and the base portion on the inner side in the tire radial direction and the base portion on the outer side in the tire radial direction than the annular layer are connected through the opening. Further, it is possible to improve durability by preventing peeling at the interface between the base material portion and the annular layer.

  In the non-pneumatic tire according to the present invention, the opening ratio of the opening with respect to the annular layer is preferably 0.05% or more. According to this configuration, the base portion on the inner side in the tire radial direction and the base portion on the outer side in the tire radial direction than the annular layer are connected with a sufficient area through the opening, and therefore, between the base portion and the annular layer. It is possible to appropriately prevent peeling at the interface.

  In the non-pneumatic tire according to the present invention, it is preferable that the opening is formed within a range of 2.5% or less of the entire width of the annular layer from both ends of the annular layer in the tire width direction. Peeling at the interface between the base material portion and the annular layer is likely to occur from both ends of the annular layer in the tire width direction, so an opening is formed within 2.5% of the total width of the annular layer from both ends in the tire width direction. By doing so, peeling at the interface can be prevented appropriately.

  In the non-pneumatic tire according to the present invention, the opening is preferably circular. By making the opening circular, the failure of the annular layer and the base material part starting from the opening can be suppressed, so that the durability can be improved.

  In the non-pneumatic tire according to the present invention, it is preferable that a plurality of the openings are formed uniformly in the tire circumferential direction. According to this configuration, peeling at the interface between the base material portion and the annular layer can be appropriately prevented over the entire circumference of the tire.

Front view showing an example of the non-pneumatic tire of the present invention The bottom view which shows an example of the non-pneumatic tire of the present invention AA sectional view of the non-pneumatic tire of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing an example of a non-pneumatic tire of the present invention. FIG. 2 is a bottom view showing an example of the non-pneumatic tire of the present invention. However, FIG. 2 shows only a part of the bottom view in an enlarged manner. FIG. 3 is a cross-sectional view taken along the line AA of FIG. Here, O indicates the axis, CD indicates the tire circumferential direction, WD indicates the tire width direction, W indicates the tire width, and H indicates the 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. However, the non-pneumatic tire T may include a member corresponding to a tread, a reinforcing member, a member for fitting with an axle or a rim, and the like on the outer side (outer peripheral side) and the inner side (inner peripheral side) of the support structure SS. Good.

  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 a plurality of connecting portions 3 that connect the outer annular portion 2 to each other.

  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 W of the inner annular portion 1 in the tire width direction WD is appropriately determined according to the use, the length of the axle, and the like, but is preferably 100 to 300 mm, assuming an alternative to a general pneumatic tire, 130 to 250 mm is more preferable.

  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. In addition, the tensile modulus in this embodiment is a value of a tensile stress when the tensile test is performed according to JIS K7312 and the elongation is 10%.

  The outer annular portion 2 is preferably cylindrical 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.

  The width W of the outer annular portion 2 in the tire width direction WD is appropriately determined according to the application, the length of the axle, and the like, but is preferably 100 to 300 mm, assuming an alternative to a general pneumatic tire, 130 to 250 mm is more preferable.

  The tensile modulus of the outer annular portion 2 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 outer annular portion 2 includes a base material portion 21 and an annular layer 4 embedded in the base material portion 21. The annular layer 4 is sandwiched between a base material portion 21 a on the inner side in the tire radial direction than the annular layer 4 and a base material portion 21 b on the outer side in the tire radial direction with respect to the annular layer 4. The width of the annular layer 4 in the tire width direction WD is the same as the width W of the outer annular portion 2 in the tire width direction WD.

  The annular layer 4 is, for example, a reinforcing layer that increases the bending rigidity of the outer annular portion 2, a cushion layer that increases the shock absorption of the non-pneumatic tire T, and the like. The annular layer 4 is formed of a material different from the base material portion 21 of the outer annular portion 2 in order to exhibit the function as a reinforcing layer or a cushion layer. When the base material portion 21 and the annular layer 4 are formed of different materials, peeling is likely to occur at the interface between the base material portion 21 and the annular layer 4.

  In the annular layer 4 of the present invention, an opening 41 that penetrates the annular layer 4 in the tire radial direction is formed. In the present embodiment, as shown in FIG. 2, a plurality of circular openings 41 are formed along the tire circumferential direction CD.

  In this invention, the opening part 41 which penetrates the cyclic | annular layer 4 is formed in the cyclic | annular layer 4, and as shown in FIG. 3, rather than the cyclic | annular layer 4, the base-material part 21a inside a tire radial direction, and the cyclic | annular layer 4 The base portion 21 b on the outer side in the tire radial direction is connected through the opening 41. Thereby, peeling at the interface between the base material portion 21 and the annular layer 4 can be prevented and durability can be improved.

  The opening ratio of the opening 41 with respect to the annular layer 4 is preferably 0.05% or more, and more preferably 0.1% or more. Further, the opening ratio of the opening 41 with respect to the annular layer 4 is preferably 50% or less, and more preferably 2% or less. Here, the aperture ratio is the ratio of the area of the opening 41 to the area of the annular layer 4 when the annular layer 4 is extended and developed on a plane. If the opening ratio of the opening 41 is smaller than 0.05%, the bonding force between the base material portion 21a and the base material portion 21b is insufficient, and thus peeling cannot be prevented appropriately. When the opening ratio of the opening 41 is larger than 50%, the function of the annular layer 4 cannot be exhibited and the durability of the annular layer 4 is deteriorated.

  The position where the opening 41 is formed is not particularly limited, but the opening 41 is preferably formed within a range of 2.5% of the total width W of the annular layer 4 from both ends of the annular layer 4 in the tire width direction. . Since peeling at the interface between the base material portion 21 and the annular layer 4 is likely to occur from both ends of the annular layer 4 in the tire width direction, the range within 2.5% of each of the total width W of the annular layer 4 from both ends in the tire width direction. By forming the opening 41 in the gap, peeling at the interface can be appropriately prevented.

  Although the opening part 41 of this embodiment is circular, the shape of the opening part 41 is not limited to this. For example, the opening 41 may be a polygon such as a triangle or a rectangle, an ellipse, or a long hole. However, from the viewpoint of preventing stress concentration and suppressing failure of the annular layer 4 and the base material portion 21 starting from the opening 41, a shape without a corner such as a circle or an ellipse is preferable.

  A plurality of openings 41 are preferably formed uniformly in the tire circumferential direction CD. According to this configuration, peeling at the interface between the base material portion 21 and the annular layer 4 can be appropriately prevented over the entire tire circumference. Moreover, according to this structure, the contact pressure fluctuation at the time of tire rolling can be suppressed.

  In the case where a plurality of openings 41 are formed, the openings 41 can be arranged in a staggered manner in addition to being arranged along the tire circumferential direction CD at both ends in the tire width direction as shown in the present embodiment. However, considering the balance in the tire width direction WD, it is preferable to arrange the openings 41 symmetrically in the tire width direction WD.

  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. The connecting portion 3 is preferably provided regularly in the tire circumferential direction CD from the viewpoint of improving uniformity.

  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. FIG. 1 shows an example in which 40 connecting portions 3 are provided.

  Examples of the shape of each connecting portion 3 include a plate-like body and a columnar body. In this embodiment, an example of a plate-like body is shown. These connecting portions 3 extend in a tire radial direction or a direction inclined from the tire radial direction in a front view. In the present invention, in the front view, the extending direction of the connecting portion 3 is preferably within ± 30 ° in the tire radial direction, and more preferably within ± 15 ° in the tire radial direction. In FIG. 1, the connection part 3 shows the example extended in the tire radial direction.

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

  The width W of the connecting portion 3 in the tire width direction WD 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. .

  The shape and arrangement of the connecting portion 3 are not limited to those shown in the present embodiment. For example, the plurality of connecting portions include a first connecting portion extending from one side in the tire width direction of the inner annular portion 1 toward the other side in the tire width direction of the outer annular portion 2, and the tire width direction of the inner annular portion 1. A configuration may be employed in which the second connecting portions extending from the other side toward the one side in the tire width direction of the outer annular portion 2 are alternately arranged along the tire circumferential direction CD.

  The non-pneumatic tire T is formed of an elastic material as a whole. However, the annular layer 4 is made of a material other than an elastic material depending on a required function. For example, when the annular layer 4 is provided as the reinforcing layer, the annular layer 4 is composed of reinforcing fibers. Examples of the reinforcing fiber include plain-woven CFRP (Carbon Fiber Reinforced Plastic) or GFRP (Glass Fiber Reinforced Plastic). When the annular layer 4 is provided as a cushion layer, the annular layer 4 is made of polyurethane, rubber or the like. Examples of polyurethane and rubber include urethane foam, impact absorbing material (product name: honeynite, etc.) and the like.

  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.

  The inner annular portion 1, the intermediate annular portion 2, and the outer annular portion 3 formed of an elastic material are preferably reinforced with reinforcing fibers.

  Reinforcing fibers include reinforcing fibers such as long fibers, short fibers, woven fabrics, and non-woven fabrics, but as a form using long fibers, fibers arranged in the tire width 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.

  When manufacturing the non-pneumatic tire T, it is preferable that the inner annular portion 1, the outer annular portion 2, and the connecting portion 3 are basically made of the same material except for the reinforcing structure from the viewpoint of enabling integral molding. .

DESCRIPTION OF SYMBOLS 1 Inner ring part 2 Outer ring part 3 Connection part 4 Ring layer 21 Base part 21a Base part 21a of a tire radial direction inner side 21b Base part of a tire radial direction outer side T Non-pneumatic tire

Claims (5)

A non-pneumatic tire comprising an inner annular portion, an outer annular portion provided concentrically outside the inner annular portion, and a connecting portion that connects the inner annular portion and the outer annular portion,
The outer annular part includes a base part and an annular layer embedded in the base part and formed of a material different from the base part,
The non-pneumatic tire, wherein the annular layer is formed with an opening penetrating the annular layer.   The non-pneumatic tire according to claim 1, wherein an opening ratio of the opening with respect to the annular layer is 0.05% or more.   3. The non-pneumatic tire according to claim 1, wherein the opening is formed within a range of 2.5% or less of a total width of the annular layer from both ends of the annular layer in the tire width direction.   The non-pneumatic tire according to any one of claims 1 to 3, wherein the opening is circular.   The non-pneumatic tire according to any one of claims 1 to 4, wherein a plurality of the openings are formed uniformly in the tire circumferential direction.

Images