JP5394304B2 - Non-pneumatic tire and manufacturing method thereof - Google Patents

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 structure member and a method for manufacturing the same, and preferably used as a substitute for a pneumatic tire. The present invention relates to a non-pneumatic tire that can be used and a manufacturing method thereof.

  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.

  Therefore, in Patent Document 1 below, for the purpose of developing a non-pneumatic tire having the same operating characteristics as a pneumatic tire, a reinforced annular band that supports a load applied to the tire, and the reinforced annular band, Non-pneumatic tires have been proposed that have a plurality of web spokes that transmit load forces by tension with a wheel or hub. The reinforced annular band comprises an elastomer shear layer, at least one first membrane adhered radially inward of the elastomer shear layer, and at least one second membrane adhered radially outward of the elastomer shear layer. Have. The first membrane and the second membrane have a structure in which a cord reinforcing material that does not substantially extend is embedded in the elastomer coating layer.

  Moreover, the following patent document 2 describes a non-pneumatic tire including a spoke structure, and a wire rod is embedded in the outer peripheral ring of the spoke structure.

Special Table 2005-500932 Publication JP 2009-286208 A

  By the way, in patent document 1, regarding the cord reinforcement material embedded in order to reinforce the 1st membrane and 2nd membrane of an annular band, the detailed position and method are not described. Moreover, also in patent document 2, it is not described about the specific position and method regarding the wire embed | buried in an outer periphery ring | wheel. However, the outer annular portion such as the annular band of Patent Document 1 and the outer peripheral ring of Patent Document 2 may be destroyed due to insufficient strength if the reinforcement is insufficient, and the non-pneumatic tire may obtain a desired durability. Can not. In addition, the belt layer and the tread layer are usually joined to the outer peripheral side of the annular band and the outer peripheral ring. However, the annular band and the outer peripheral ring are insufficient due to the above-described strength and insufficient adhesion to the adjacent belt layer. , Peeling is likely to occur between the belt layer.

  Accordingly, an object of the present invention is a non-pneumatic tire provided with a support structure that supports a load from a vehicle, by reinforcing the outer annular portion of the support structure and improving the adhesive force to the belt layer, An object is to provide a non-pneumatic tire with improved durability and a method for manufacturing the same.

The above object can be achieved by the present invention as described below.
That is, the non-pneumatic tire according to the present invention is a non-pneumatic tire including a support structure that supports a load from a vehicle and a belt layer provided on an outer peripheral side of the support structure, and the support structure includes an inner annular portion. And an outer annular portion provided concentrically on the outer side of the inner annular portion, and a plurality of connecting portions that connect the inner annular portion and the outer annular portion, and on the outer circumferential surface of the outer annular portion. The reinforcing fiber is embedded in an annular shape in a partially exposed state.

  The non-pneumatic tire of the present invention includes a support structure that supports a load from a vehicle, and a belt layer that is provided on the outer peripheral side of the support structure. Reinforcing fibers are embedded in an annular shape on the outer peripheral surface of the outer annular portion of the support structure in a partially exposed state. According to this configuration, the outer annular portion is reinforced by the embedded reinforcing fiber, and deformation of the outer annular portion is suppressed. Further, since the reinforcing fibers are partially exposed on the outer peripheral surface of the outer annular portion, an anchor effect occurs when the belt layer is joined to the outer peripheral side of the support structure, that is, the outer peripheral side of the outer annular portion, and the support structure Adhesion to body belt layer is improved. As a result, according to the present invention, a non-pneumatic tire with improved durability can be provided.

  In the non-pneumatic tire according to the present invention, the support structure is preferably made of a polyurethane resin using paraphenylene diisocyanate (PPDI) as an isocyanate component.

  By constituting with a polyurethane resin using paraphenylene diisocyanate (PPDI) as an isocyanate component, the bending fatigue resistance of the support structure is improved, the durability is improved, and the hydrolysis resistance is also improved.

  On the other hand, the manufacturing method of a 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 plurality of connecting the inner annular portion and the outer annular portion. A non-pneumatic tire manufacturing method comprising a support structure comprising a connecting portion for forming an inner mold for forming the inner peripheral side of the inner annular part and an outer peripheral side of the outer annular part A plurality of cores for forming the outer side of the inner annular part, the outer peripheral side of the outer annular part, the inner peripheral side of the outer annular part, and the connecting part, between the outer mold and the outer mold Disposing a pair of upper and lower molds for molding both sides of the support structure in the tire width direction, and forming cavities corresponding to the inner annular part, the outer annular part, and the connecting part; The reinforcing fibers are annularly arranged so as to contact the inner peripheral surface of the outer mold. A step of supplying a raw material liquid of an elastic material to the cavity to be cured and molding the support structure, and a step of bonding a belt layer to the outer peripheral side of the molded support structure. It is characterized by that.

  According to this configuration, the outer peripheral surface of the outer annular portion of the support structure is formed by arranging the reinforcing fibers in an annular shape so as to contact the inner peripheral surface of the outer mold and supplying the raw material liquid of the elastic material to the cavity and curing it. In addition, the reinforcing fiber is embedded in a partially exposed state. Thereby, as described above, a non-pneumatic tire with improved durability can be manufactured.

  In the method for manufacturing a non-pneumatic tire according to the present invention, it is preferable that a step of buffing the outer peripheral surface of the formed support structure is provided after the step of forming the support structure.

  When forming the support structure by curing the raw material liquid of the elastic material, the raw material liquid is slightly between the reinforcing fiber and the outer mold even if the reinforcing fibers are arranged in an annular shape so as to contact the inner peripheral surface of the outer mold. In some cases, a thin film of an elastic material is formed on the outer peripheral surface of the reinforcing fiber. By buffing the outer peripheral surface of the formed support structure, the thin film of the elastic material is removed, and the reinforcing fibers embedded in the outer peripheral surface of the outer annular portion can be reliably exposed.

(A) which shows an example of the non-pneumatic tire of this invention is a front view, (b) is a partially enlarged view Perspective view showing annular reinforcing fiber (A) which shows the shaping | molding die for shape | molding a support structure is a front view, (b) is a longitudinal cross-sectional view Perspective view showing another embodiment of the medium size Perspective view showing another embodiment of the medium size

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the configuration of the non-pneumatic tire of the present invention will be described. FIG. 1 is a front view showing an example of a non-pneumatic tire, (a) is an overall view, and (b) is a partially enlarged view. Here, O indicates the axial center, and H1 indicates the tire cross-sectional height.

  The non-pneumatic tire T of the present invention includes a support structure SS that supports a load from a vehicle, and a belt layer 6 provided on the outer peripheral side of the support structure SS. The non-pneumatic tire T of the present invention only needs to have such a support structure SS and the belt layer 6, and the outer side (outer peripheral side) and the inner side (inner peripheral side) of the support structure SS and the belt layer 6. Further, a tread layer 7, 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 according to the present embodiment includes an inner annular portion 1, an intermediate annular portion 2 provided concentrically on the outer side thereof, and an outer side thereof. A concentric outer ring part 3, an inner ring part 1, an intermediate ring part 2, a plurality of inner connection parts 4 that are independent in the circumferential direction, an outer ring part 3, and an intermediate ring part 2 And a plurality of outer connecting portions 5 that are independent of each other in the circumferential direction. In this embodiment, the support structure SS includes the intermediate annular portion 2, but the intermediate annular portion 2 is not always necessary, and the intermediate annular portion 2 is not provided, and the inner connecting portion 4 and the outer connecting portion 5 are continuous. However, you may comprise one connection part.

  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 2 to 10% and 3 to 7% of the tire cross-section height H1 from the viewpoint of reducing weight and improving durability while sufficiently transmitting force to the inner connecting portion 4. More preferred.

  The inner annular portion 1 has an inner diameter that is appropriately determined in accordance with the dimensions of the rim on which the non-pneumatic tire T is mounted, the axle, and the like. It can be made much smaller. 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 axial width of the inner annular portion 1 is appropriately determined according to the application, the length of the axle, and the like, but when an alternative to a general pneumatic tire is assumed, it is preferably 100 to 300 mm, more preferably 130 to 250 mm. 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 inner connecting portion 4. 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. From the viewpoint of enabling integral molding when the support structure SS is manufactured, the inner annular portion 1, the intermediate annular portion 2, and the outer annular portion 3 are used. The inner connecting portion 4 and the outer connecting portion 5 are preferably basically made of 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 95 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. Among polyurethane resins, those using paraphenylene diisocyanate (PPDI) as the isocyanate component of the main raw material are particularly preferable. Polyurethane resins using PPDI have excellent bending fatigue resistance and hydrolysis resistance. Polyurethane resins using PPDI have lower exothermicity due to hysteresis (low exothermic properties) and better dynamic characteristics than polyurethane resins using toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI). . As the polyol component of the polyurethane resin, ester (adipate), caprolactone, carbonate, ether, and the like can be used. Of these, ester (adipate), caprolactone, and carbonate are better in bending fatigue resistance and other mechanical properties, while ether> carbonate> caprolactone in hydrolysis resistance. Although the order of the system> ester (adipate) system, the polyurethane resin using PPDI is higher in water resistance than the polyurethane resin using TDI, regardless of which polyol component is used. Degradable. In addition, as an elastic material, you may use a foam material, The thing which foamed said thermoplastic elastomer, crosslinked rubber, and other resin can be used.

  In the support structure SS integrally formed of an elastic material, the inner annular portion 1, the intermediate annular portion 2, the outer annular portion 3, the inner connecting portion 4, and the outer connecting portion 5 are preferably reinforced with 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.

  In the present embodiment, the inner annular portion 1 is reinforced by reinforcing fibers 1a embedded in the central portion of the radial thickness. Examples of the reinforcing fiber 1a include the cord material wound in the tire circumferential direction and a net-like fiber aggregate formed in an annular shape. By reinforcing the inner annular portion 1 with the reinforcing fiber 1a, the fitting force with the wheel is increased, the shift (slip) from the wheel can be suppressed, and the deformation at the time of loading can be suppressed. Further, since the reinforcing fiber 1a is embedded in the central portion of the inner annular portion 1 in the radial direction, the reinforcing fiber 1a is not exposed to the inner peripheral surface of the inner annular portion 1, and damage to both the reinforcing fiber 1a and the wheel is prevented. Can do.

  Further, the inner annular portion 1 may be formed by annularly arranging the organic fiber material 1b on the inner peripheral side of the reinforcing fiber 1a. By disposing the organic fiber material 1b on the inner peripheral side of the reinforcing fiber 1a, the reinforcing fiber 1a can be prevented from being exposed to the inner peripheral surface of the inner annular portion 1. Such an organic fiber material can be constituted by a woven fabric or a net, and a known fiber material can be used without limitation. Examples include rayon, polyamide fibers such as nylon-6,6, polyester fibers such as polyethylene terephthalate, and aramid fibers.

  The shape of the intermediate annular portion 2 is not limited to a cylindrical shape, and may be a polygonal cylindrical shape.

  The thickness of the intermediate annular portion 2 is preferably 2 to 10% of the tire cross-section height H1 from the viewpoint of reducing weight and improving durability while sufficiently reinforcing the inner connecting portion 4 and the outer connecting portion 5. -9% is more preferable.

  The inner annular portion 2 has an inner diameter that exceeds the inner diameter of the inner annular portion 1 and less than the inner diameter of the outer annular portion 3. However, as the inner diameter of the intermediate annular portion 2, the inner diameter of the inner annular portion 1 is subtracted from the inner diameter of the outer annular portion 3 from the viewpoint of improving the reinforcing effect of the inner connecting portion 4 and the outer connecting portion 5 as described above. A value of 20 to 80% of the value is preferably the inner diameter added to the inner diameter of the inner annular portion 1, and a value of 30 to 60% is more preferably the inner diameter added to the inner diameter of the inner annular portion 1. .

  The axial width of the intermediate annular portion 2 is appropriately determined according to the application and the like, but is preferably 100 to 300 mm, more preferably 130 to 250 mm, assuming an alternative to a general pneumatic tire.

  The tensile modulus of the intermediate annular portion 2 is preferably 8000 to 18000 MPa, more preferably 10,000 to 50000 MPa from the viewpoint of sufficiently reinforcing the inner connecting portion 4 and the outer connecting portion 5 to improve durability and load capacity. preferable.

  Since the tensile modulus of the intermediate annular portion 2 is preferably higher than that of the inner annular portion 1, a fiber reinforced material in which a thermoplastic elastomer, a crosslinked rubber, or other resin is reinforced with fibers or the like is preferable.

  The shape of the outer annular portion 3 is preferably a cylindrical shape with a constant thickness from the viewpoint of improving uniformity. The thickness of the outer annular portion 3 is preferably 2 to 10% of the tire cross-section height H1, and preferably 3 to 7% from the viewpoint of reducing the weight and improving the durability while sufficiently transmitting the force from the outer connecting portion 5. Is more preferable.

  The inner diameter of the outer annular portion 3 is appropriately determined according to its use and the like, but since the intermediate annular portion 2 is provided in the present invention, the inner diameter of the outer annular portion 3 can be made larger than before. 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 axial width of the outer annular portion 3 is appropriately determined according to the application 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 outer annular portion 3 can be set to the same level as that of the inner annular portion 1 when the belt layer 6 is provided on the outer periphery of the outer annular portion 3 as shown in FIG. When such a belt layer 6 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 outer connecting portion 5. .

  When the tensile modulus of the outer annular portion 3 is increased, a fiber reinforced material obtained by reinforcing an elastic material with fibers or the like is preferable. In the present embodiment, the outer annular portion 3 is reinforced by an annular reinforcing fiber 3a embedded in the outer peripheral surface. The reinforcing fiber 3a is embedded in a state where a part thereof is exposed on the surface of the outer annular portion 3. Thus, when the reinforcing fibers 3a are partially exposed, an anchor effect is produced when the belt layer 6 is joined to the outer peripheral side of the outer annular portion 3, and the adhesion between the outer annular portion 3 and the belt layer 6 is caused. It will be enough.

  In the present embodiment, an annular reinforcing fiber as shown in FIG. 2 is used as the reinforcing fiber 3a. The reinforcing fibers 3a are made of non-extensible glass fiber cords arranged in a lattice shape, and are obtained by forming a band-like body obtained by cutting a sheet-like glass fiber net in an annular shape.

  The inner connecting portion 4 connects the inner annular portion 1 and the intermediate annular portion 2, and a plurality of inner connecting portions 4 are provided so that each is independent in the circumferential direction, for example, by providing an appropriate interval therebetween. The inner connecting portion 4 is preferably provided regularly in the circumferential direction from the viewpoint of improving uniformity.

  As for the number of inner connection parts 4 provided over the entire circumference (when a plurality of inner connection parts 4 are provided in the axial direction, it is counted as one), while supporting the load from the vehicle sufficiently, weight reduction, improvement of power transmission, durability From the viewpoint of improving the quality, 10 to 80 are preferable, and 30 to 60 are more preferable. FIG. 1 shows an example in which 40 inner connecting portions 4 are provided.

  Examples of the shape of each inner connecting portion 4 include a plate-like body and a columnar body. In this embodiment, an example of a plate-like body is shown. These inner connection parts 4 are extended in the tire radial direction or the direction inclined from the tire radial direction in the front sectional view. In the present invention, from the viewpoint of improving the durability by increasing the break point and making it difficult to change the rigidity, the extending direction of the inner connecting portion 4 is preferably within ± 30 ° in the tire radial direction in the front sectional view. The tire radial direction is more preferably within ± 15 °. FIG. 1 shows an example in which the inner connecting portion 4 is extended in the tire radial direction.

  The thickness of the inner connecting portion 4 is preferably 1 to 12% of the tire cross-section height H1 from the viewpoint of reducing weight, improving durability, and improving lateral rigidity while sufficiently transmitting the force from the inner annular portion 1. 2 to 10% is more preferable.

  The tensile modulus of the inner connecting portion 4 is preferably 5 to 100 MPa, more preferably 7 to 95 MPa from the viewpoint of reducing weight, improving durability, and improving lateral rigidity while sufficiently transmitting the force from the inner annular portion 1. preferable.

  When the tensile modulus of the inner connecting portion 4 is increased, a fiber reinforced material obtained by reinforcing an elastic material with fibers or the like is preferable.

  The outer connecting portion 5 connects the outer annular portion 3 and the intermediate annular portion 2, and a plurality of outer connecting portions 5 are provided so that each of them is independent in the circumferential direction, for example, by providing an appropriate interval therebetween. The outer connecting portion 5 is preferably provided regularly in the circumferential direction from the viewpoint of improving uniformity.

  In addition, the outer side connection part 5 and the inner side connection part 4 may be provided in the same position of a perimeter, and may be provided in a different position. That is, the outer connecting portion 5 and the inner connecting portion 4 do not necessarily extend so as to be continuous in the same direction as shown in FIG.

  As for the number of outer connecting parts 5 provided over the entire circumference (when a plurality of outer connecting parts 5 are provided in the axial direction, they are counted as one), while supporting the load from the vehicle sufficiently, weight reduction, improvement of power transmission, durability From the viewpoint of improving the quality, 10 to 80 are preferable, and 30 to 60 are more preferable. FIG. 1 shows an example in which 40 outer connecting portions 5 are provided in the same manner as the inner connecting portions 4. In addition, the number of the outer side connection parts 5 and the number of the inner side connection parts 4 do not necessarily need to be the same, and you may provide more outer side connection parts 5 than the inner side connection parts 4. FIG.

  Examples of the shape of each outer connecting portion 5 include a plate-like body and a columnar body. In this embodiment, an example of a plate-like body is shown. These outer connecting portions 5 extend in a tire radial direction or a direction inclined from the tire radial direction in a front sectional view. In the present invention, from the viewpoint of improving the durability by increasing the break point and making it difficult to change the rigidity, the extending direction of the outer connecting portion 5 is preferably within ± 30 ° in the tire radial direction in the front sectional view. The tire radial direction is more preferably within ± 15 °. FIG. 1 shows an example in which the outer connecting portion 5 is extended in the tire radial direction.

  The thickness of the outer connecting portion 5 is preferably 1 to 12% of the tire cross-sectional height H1 from the viewpoint of reducing weight, improving durability, and improving lateral rigidity while sufficiently transmitting the force from the inner annular portion 1. 2 to 10% is more preferable.

  The tensile modulus of the outer connecting portion 5 is preferably 5 to 100 MPa, more preferably 7 to 95 MPa from the viewpoint of reducing weight, improving durability, and improving lateral rigidity while sufficiently transmitting the force from the inner annular portion 1. preferable.

  In order to increase the tensile modulus of the outer connecting portion 5, a fiber reinforced material obtained by reinforcing an elastic material with fibers or the like is preferable.

  In the present embodiment, as shown in FIG. 1, an example is shown in which a belt layer 6 that reinforces bending deformation of the outer annular portion 3 is provided on the outer peripheral side of the outer annular portion 3 of the support structure SS. As the belt layer 6, the same belt layer as that of a conventional pneumatic tire can be provided.

  The belt layer 6 is composed of one or a plurality of layers. For example, a steel cord, an aramid cord, a rayon cord, or the like, which is arranged in parallel at an inclination angle of about 20 ° with respect to the tire circumferential direction, is a steel cord. Etc. can be formed so as to cross in the opposite direction. Further, a layer made of various cords arranged in parallel in the tire circumferential direction may be provided on the upper layer of both layers.

  In the present embodiment, as shown in FIG. 1, an example in which a tread layer 7 is provided on the outer side of the belt layer 6 is shown, but in the present invention, on the outermost layer on the outer side of the outer annular portion 3 in this way, A tread layer 7 is preferably provided. As the tread layer 7, it is possible to provide the same tread layer as that of a conventional pneumatic tire. Moreover, it is possible to provide the same pattern as a conventional pneumatic tire as a tread pattern.

  For example, the raw material of the tread rubber forming the tread layer 7 includes natural rubber, styrene butadiene rubber (SBR), butadiene rubber (BR), isoprene rubber (IR), butyl rubber (IIR) and the like. These rubbers are reinforced with fillers such as carbon black and silica, and a vulcanizing agent, a vulcanization accelerator, a plasticizer, an antiaging agent, and the like are appropriately blended.

<Method for producing non-pneumatic tire>
The manufacturing method of the present invention is a manufacturing method capable of suitably manufacturing the non-pneumatic tire T of the present invention as described above, and includes a middle mold for molding the inner peripheral side of the inner annular portion 1 and the outer annular portion 3. An outer mold for molding the outer peripheral side, and an intermediate mold and an outer mold are arranged in the circumferential direction, and the outer peripheral side of the inner annular part 1, the inner peripheral side of the outer annular part 3, and the connecting parts 4 and 5 are molded. And a pair of upper molds and lower molds for forming both side surfaces in the tire width direction of the support structure SS are arranged, and the inner annular portion 1, the outer annular portion 3 and the connecting portion 4 are arranged. 5, a step of forming a cavity corresponding to 5, a step of annularly arranging the reinforcing fibers 3a so as to be in contact with the inner peripheral surface of the outer mold, a raw material liquid of an elastic material is supplied to the cavity and cured, and the support structure SS And a step of joining the belt layer 6 to the outer peripheral side of the molded support structure SS. Characterized in that it comprises a and.

  FIG. 3 shows a forming die for forming the support structure SS, (a) a front view and (b) a longitudinal sectional view. The mold 10 has a cavity C corresponding to the support structure SS. Each of the cavities C1 to C5 corresponds to the inner annular portion 1, the intermediate annular portion 2, the outer annular portion 3, the inner coupling portion 4, and the outer coupling portion 5 of the support structure SS, respectively. Such a space C is formed by the middle mold 11, the outer mold 12, the cores 13 and 14, the upper mold 15 (not shown in FIG. 3A), and the lower mold 16. The middle die 11 is formed on the inner peripheral side of the inner annular portion 1, the outer die 12 is formed on the outer peripheral side of the outer annular portion 3, and the core 13 is formed between the outer peripheral side of the inner annular portion 1 and the intermediate annular portion 2. The inner peripheral side and the inner connecting part 4 are formed, and the core 14 is for forming the inner peripheral side of the outer annular part 3, the outer peripheral side of the intermediate annular part 2, and the outer connecting part 5. Moreover, the upper mold | type 15 and the lower mold | type 16 are for shape | molding the tire width direction both sides | surfaces of support structure SS. The middle mold 11, the outer mold 12, and the cores 13 and 14 can be fixed to the lower mold 16, and the upper mold 15 can be opened and closed with respect to the lower mold 16.

  Reinforcing fibers 3a are annularly arranged in the cavity C3 between the outer mold 12 and the core 14 so as to contact the inner peripheral surface of the outer mold 12. When the reinforcing fiber 3a is formed in an annular shape, the reinforcing fiber 3a preferably retains its annular shape and can be self-supporting. If the reinforcing fiber 3a is too soft to stand on its own, it may be made self-supporting by coating with a resin. Examples of the coating resin include polyurethane primers and resin emulsions.

  In the cavity C <b> 1 between the middle mold 11 and the core 13, the reinforcing fibers 1 a are arranged in an annular shape. The reinforcing fibers 1a are preferably arranged so as not to contact the outer peripheral surface of the middle mold 11. The reinforcing fiber 1a is constituted by a cord material wound in the circumferential direction or a net-like fiber aggregate formed in an annular shape.

  When the cord material or the net-like fiber assembly is arranged in the cavity C1, the belt-like organic fiber material 1b is wound around the outer peripheral surface of the middle mold 11, and the cord material is wound around the outer periphery. The reinforcing fiber 1a may be configured by winding.

  Further, as shown in FIG. 4, a plurality of protrusions 17 extending in the axial direction of the support structure SS may be provided on the outer peripheral surface of the middle mold 11 at a predetermined pitch in the circumferential direction. The reinforcing fiber 1a may be configured by winding a cord material so as to be spanned around the outer periphery of the ridge 17, or winding a belt-like net-like fiber aggregate. Thereby, a gap is formed between the outer peripheral surface of the middle mold 11 and the reinforcing fiber 1a.

  Further, instead of providing the above-mentioned protrusion 17 on the intermediate mold 11, a plurality of spacers are arranged on the outer peripheral surface of the intermediate mold 11, and a cord material is wound around the outer periphery, or a belt-like net-like fiber assembly The body may be wound to form the reinforcing fiber 1a. Thereby, a gap is formed between the outer peripheral surface of the middle mold 11 and the reinforcing fiber 1a.

  Further, as shown in FIG. 5, the middle mold 11 includes a core portion 11 a that constitutes an inner peripheral portion thereof, and a ring portion 11 b that constitutes the outer peripheral portion thereof and is configured to be fitted on the core portion 11 a. It is preferable to provide it. In this way, by configuring the middle mold 11 so as to be split into the core part 11a and the ring part 11b, when the cord material is wound around the middle mold 11, only the ring part 11b is removed from the molding die 10 in the ring part. A cord material or a net-like fiber assembly can be wound around the outer periphery of 11b. If it is only the ring portion 11b, it is lightweight and easy to handle. Also, by preparing a plurality of ring portions 11b, on the one hand, a cord material or the like is wound around the removed ring portion 11b, and on the other hand, the ring portion 11b around which the cord material or the like is wound is externally fitted to the core portion 11a. The support structure SS, which will be described later, can be molded, and the manufacturing efficiency can be improved.

  Next, the cavity C of the mold 10 is filled with a raw material liquid of an elastic material. Examples of the raw material liquid for the elastic material include those obtained by softening the above-described elastic material at a high temperature, and liquid raw materials before reaction curing or before crosslinking. At the time of filling, it is preferable that the viscosity of the raw material liquid is small at the time of filling in order to suitably enter the gap of the cavity C and impregnate the reinforcing fibers.

  In addition, a method of applying centrifugal force is also effective for the purpose of uniformly filling the raw material liquid. In that case, a method can be used in which the lower mold 16 of the mold 10 is formed in a disk shape and the mold 10 is rotated around the axis O by a motor or the like.

  Next, the support structure SS can be obtained by solidifying and removing the raw material liquid of the elastic material. Examples of the method for solidifying the raw material liquid include reaction curing, heat curing, and cooling solidification. In order to facilitate demolding, it is effective to make the cores 13 and 14 of the mold 10 detachable.

  After demolding, a post-cure process or the like can also be performed. The outer peripheral surface of the formed support structure SS is buffed. Thereafter, the belt layer 6 and the tread layer 7 are wound around and bonded to the outer peripheral side of the support structure SS via an adhesive. In the case where the belt layer 6 and the tread layer 7 are made of unvulcanized rubber, the belt layer 6 and the tread layer 7 are wound around the outer peripheral side of the support structure SS and then vulcanized with a hot press machine or the like.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below. In addition, the evaluation item in an Example etc. measured as follows.

(1) Fitting force Using a fitting force tester manufactured by HOFMANN, the inner diameter of the inner annular portion 1 at a load of 500 N is measured and set as a reference diameter. Then, the fitting force when the reference diameter is +1 mm is measured. The result is shown as an index when Comparative Example 1 is set to 100. The larger this value, the better.

(2) Wheel scraping After mounting the non-pneumatic tire T on the wheel and running for 2 hours with a drum tester (80 km / h), the wheel surface in contact with the non-pneumatic tire T is visually observed.

(3) Peeling force The non-pneumatic tire T is disassembled, and a 25 mm wide test piece composed of the outer annular portion 3 and the belt layer 6 of the support structure SS is collected. The test piece is peeled in advance at the interface between the outer annular portion 3 and the belt layer 6 at one end of the test piece, and the peeled outer annular portion 3 and the belt layer 6 are sandwiched by the upper and lower chucks of an Instron universal testing machine. Degree peel test (normal temperature, tensile speed 50 mm / min) is carried out. The result is shown as an index when Comparative Example 1 is set to 100. The larger this value, the better.

(4) Running durability A non-pneumatic tire T is mounted on a wheel, and a test is performed with a drum tester under the conditions of 80 km / h and a load of 350 kg, and the running distance until a failure occurs in the support structure SS is measured. . The result is shown as an index when Example 6 is taken as 100. The larger this value, the better.

(5) Middle mold handling workability Since the middle mold 11 of the molding die 10 is configured to be split into the core part 11a and the ring part 11b, the ring part 11b alone can be removed from the middle mold 11 so that the work can be performed. Workability is good. When the middle mold 11 can be divided into the core part 11a and the ring part 11b, the middle mold handling workability is improved.

<Example 1>
Only the ring part 11b is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device. First, a nylon net (111-B made by Izumi Co., Ltd.) as the organic fiber material 1b is attached to the outer periphery of the ring part 11b. Wind twice around the surface and fix both ends. Next, one layer of aramid cord (manufactured by Toray DuPont, KEVLAR, 3300 dtex, fiber diameter 0.6 mm) as a reinforcing fiber 1a is spirally formed at a tension of 30 N so that the number of ends is 8 / inch. Wind. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3 a is inserted into the cavity C <b> 3 between the outer mold 12 and the core 14 along the inner peripheral surface of the outer mold 12. Then, after the mold 10 was heated to a predetermined temperature, 4800 parts by weight of a PPDI-terminated prepolymer adiprene LFP950A (Chemtura), polytetramethylene ether glycol (PTMG) (Mitsubishi Chemical Co., molecular weight 1000) 345 parts by weight and 1,4-butanediol (1,4-BD) (BASF Idemitsu Co., Ltd.) 230 parts by weight were previously degassed under reduced pressure, and the liquid temperature was adjusted to 70 ° C. After mixing, the mixture is poured into the cavity C of the mold 10 and cured in an oven at 110 ° C. for 1 hour, then demolded, and further post-cured in an oven at 110 ° C. for 16 hours to form a support structure SS. Was made. After the outer peripheral surface of the outer annular portion 3 of the support structure SS is buffed with sandpaper, a predetermined amount of adhesive XJ-423 (manufactured by LORD) is applied and dried in an oven at 70 ° C. for 30 minutes. After drying, the unvulcanized belt layer 6 and the tread layer 7 were wound and subjected to hot pressing to produce a non-pneumatic tire T. The results of evaluating the performance are shown in Table 1.

<Example 2>
Only the ring part 11b is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device, and an aramid cord (Kevlar, 3300 dtex, fiber diameter 0.6 mm, manufactured by Toray DuPont) is used as the reinforcing fiber 1a. One layer is wound at a tension of 30 N in a spiral shape so that the number of ends is 8 / inch. At that time, immediately before the aramid cord is wound, 32 spacers having a thickness of 1.5 mm are arranged on the outer peripheral surface of the ring portion 11b so as to be inserted between the aramid cord and the ring portion 11b at a predetermined interval. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3 a is inserted into the cavity C <b> 3 between the outer mold 12 and the core 14 along the inner peripheral surface of the outer mold 12. Subsequent methods and conditions were the same as those in Example 1.

<Example 3>
Only the ring portion 11b provided with 32 protrusions 17 at a predetermined interval of 1.5 mm in height on the outer peripheral surface is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device, thereby reinforcing fiber 1a. As a belt-like glass fiber net (manufactured by Nittobo Co., Ltd., KS3815), one layer is wound at a tension of 30N. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3 a is inserted into the cavity C <b> 3 between the outer mold 12 and the core 14 along the inner peripheral surface of the outer mold 12. Subsequent methods and conditions were the same as those in Example 1.

<Example 4>
Only the ring part 11b is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device. First, a nylon net (111-B made by Izumi Co., Ltd.) as the organic fiber material 1b is attached to the outer periphery of the ring part 11b. Wind twice around the surface and fix both ends. Next, a belt-like glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 1a is wound around one layer at a tension of 30N. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3 a is inserted into the cavity C <b> 3 between the outer mold 12 and the core 14 along the inner peripheral surface of the outer mold 12. Subsequent methods and conditions were the same as those in Example 1.

<Example 5>
Only the ring portion 11b is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device, and one layer of a belt-shaped glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 1a is formed at one layer. Wind. At that time, just before winding the glass fiber net, 32 spacers having a thickness of 1.5 mm are arranged on the outer peripheral surface of the ring portion 11b at a predetermined interval between the glass fiber net and the ring portion 11b. To do. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3 a is inserted into the cavity C <b> 3 between the outer mold 12 and the core 14 along the inner peripheral surface of the outer mold 12. Subsequent methods and conditions were the same as those in Example 1.

<Example 6>
Only the ring part 11b is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device. First, a nylon net (111-B made by Izumi Co., Ltd.) as the organic fiber material 1b is attached to the outer periphery of the ring part 11b. Wind twice around the surface and fix both ends. Next, one layer of aramid cord (manufactured by Toray DuPont, KEVLAR, 3300 dtex, fiber diameter 0.6 mm) as a reinforcing fiber 1a is spirally formed at a tension of 30 N so that the number of ends is 8 / inch. Wind. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3 a is inserted into the cavity C <b> 3 between the outer mold 12 and the core 14 along the inner peripheral surface of the outer mold 12. Thereafter, after the mold 10 is heated to a predetermined temperature, 4560 parts by weight of UDI-6 (manufactured by Soflanwiz), a TDI-terminated prepolymer, is previously degassed under reduced pressure, and the liquid temperature is adjusted to 70 ° C. Thereafter, 816 parts by weight of Iharacamine MT (MOCA) (manufactured by Ihara Chemical Industry Co., Ltd.) having a liquid temperature of 130 ° C. was added thereto, and the mixture was stirred and mixed. The mixture was poured into the cavity C of the mold 10, and 100 ° C. Curing was performed in an oven for 1 hour, then demolded, and further post-curing was performed in an oven at 70 ° C. for 16 hours to produce a support structure SS. After the outer peripheral surface of the outer annular portion 3 of the support structure SS is buffed with sandpaper, a predetermined amount of adhesive XJ-423 (manufactured by LORD) is applied and dried in an oven at 70 ° C. for 30 minutes. After drying, the unvulcanized belt layer 6 and the tread layer 7 were wound and subjected to hot pressing to produce a non-pneumatic tire T.

<Comparative Example 1>
After heating the mold 10 to a predetermined temperature, 4560 parts by weight of UTM-6 (manufactured by Soflanwiz) of TDI terminal prepolymer was previously degassed under reduced pressure, and the liquid temperature was adjusted to 70 ° C. 816 parts by weight of Iharacamine MT (MOCA) (manufactured by Ihara Chemical Industry Co., Ltd.) having a liquid temperature of 130 ° C. was added thereto, stirred and mixed, and the mixture was poured into the cavity C of the mold 10 and placed in an oven at 100 ° C. The substrate was cured for 1 hour, then demolded, and further post-cured in an oven at 70 ° C. for 16 hours to prepare a support structure SS. After the outer peripheral surface of the outer annular portion 3 of the support structure SS is buffed with sandpaper, a predetermined amount of adhesive XJ-423 (manufactured by LORD) is applied and dried in an oven at 70 ° C. for 30 minutes. After drying, the unvulcanized belt layer 6 and the tread layer 7 were wound and subjected to hot pressing to produce a non-pneumatic tire T.

<Comparative example 2>
Remove the entire middle mold 11 from the molding die 10 and attach it to the rotating shaft of the tension load device. Aramid cord (Kevlar, 3300 dtex, manufactured by Toray DuPont, fiber diameter 0.6mm) as the reinforcing fiber 1a has 8 ends. 1 layer is wound at a tension of 30 N in a spiral so as to be / inch. The middle mold 11 is removed from the rotating shaft of the tension load device and attached to the mold 10. Subsequent methods and conditions were the same as those in Comparative Example 1.

<Comparative Example 3>
An annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 1 a is inserted into the cavity C <b> 1 between the middle mold 11 and the core 13 along the outer peripheral surface of the middle mold 11. Subsequent methods and conditions were the same as those in Comparative Example 1.

<Comparative Example 4>
Only the ring portion 11b provided with 32 protrusions 17 at a predetermined interval of 1.5 mm in height on the outer peripheral surface is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device, thereby reinforcing fiber 1a. Aramid cord (manufactured by Toray DuPont, KEVLAR, 3300 dtex, fiber diameter 0.6 mm) is spirally wound at a tension of 30 N so that the number of ends is 8 / inch. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Subsequent methods and conditions were the same as those in Comparative Example 1.

<Comparative Example 5>
Only the ring part 11b is removed from the middle mold 11 of the molding die 10, and is externally fitted to the drum of the tension load device. First, a nylon net (111-B made by Izumi Co., Ltd.) as the organic fiber material 1b is attached to the outer periphery of the ring part 11b. Wind twice around the surface and fix both ends. Next, one layer of aramid cord (manufactured by Toray DuPont, KEVLAR, 3300 dtex, fiber diameter 0.6 mm) as a reinforcing fiber 1a is spirally formed at a tension of 30 N so that the number of ends is 8 / inch. Wind. Next, the ring portion 11 b is removed from the drum of the tension load device and is fitted onto the core portion 11 a of the middle mold 11. Next, an annular glass fiber net (manufactured by Nittobo Co., Ltd., KS3815) as the reinforcing fiber 3a is inserted into the cavity C3 between the outer mold 12 and the core 14 so as not to contact the inner peripheral surface of the outer mold 12. . Subsequent methods and conditions were the same as those in Example 1.

  In the non-pneumatic tires T of Examples 1 to 6 in which the reinforcing fibers 3a are embedded in an annular shape in a state of being partially exposed on the outer peripheral surface of the outer annular portion 3, the outer annular portion 3 and the belt layer 6 are sufficiently bonded. Thus, the peel force is greater than in Comparative Examples 1-5.

  The non-pneumatic tires T of Examples 1 to 6 including the support structure SS manufactured by a polyurethane resin using PPDI as an isocyanate component have higher running durability than those using conventional TDI. In addition, the running durability of Examples 1 to 6 is displayed as 1000 to 1200 or more because a failure due to separation occurs between the outer annular portion 3 and the belt layer 6 before the support structure SS fails. This is because.

  Compared with the non-pneumatic tire T of Comparative Example 1 in which the inner annular portion 1 is not reinforced by the reinforcing fiber 1a, the non-pneumatic tire T reinforced by the reinforcing fiber 1a has a larger fitting force.

  Further, wheel scraping was observed in the non-pneumatic tire T of Comparative Example 3 in which there was no gap between the middle mold 11 and the glass fiber net as the reinforcing fiber 1a. However, in the case of Comparative Example 2 using an aramid cord as the reinforcing fiber 1a, wheel scraping was not observed because it was an organic fiber material. That is, when a glass fiber net is used as the reinforcing fiber 1a of the inner annular portion 1, the reinforcing fiber 1a is formed into the inner annular portion by providing a gap between the middle mold 11 and the reinforcing fiber 1a as in Examples 3 to 5. Since it is not exposed to the inner peripheral surface of 1, the damage of both the reinforcing fiber 1a and the wheel can be prevented.

<Other embodiments>
In the above-described embodiment, an example in which only one intermediate annular portion 2 is provided has been described. However, in the present invention, a plurality of intermediate annular portions 2 may be provided. Thereby, it is possible to make the inner diameter of the inner annular portion 1 smaller.

DESCRIPTION OF SYMBOLS 1 Inner annular part 2 Middle annular part 3 Outer annular part 3a Reinforcing fiber 4 Inner coupling part 5 Outer coupling part 6 Belt layer 7 Tread layer 10 Mold 11 Central mold 12 Outer mold 13 Core 14 Core 15 Upper mold 16 Lower mold C Cavity SS Support structure T Non-pneumatic tire

Claims (4)

In a non-pneumatic tire comprising a support structure that supports a load from a vehicle, and a belt layer provided on the outer peripheral side of the support structure,
The support structure includes an inner annular portion, an outer annular portion provided concentrically on the outer side of the inner annular portion, and a plurality of connecting portions that connect the inner annular portion and the outer annular portion,
A non-pneumatic tire characterized in that a reinforcing fiber is embedded in an annular shape on the outer peripheral surface of the outer annular portion in a partially exposed state.   The non-pneumatic tire according to claim 1, wherein the support structure is made of a polyurethane resin using paraphenylene diisocyanate (PPDI) as an isocyanate component. A support structure including an inner annular portion, an outer annular portion provided concentrically outside the inner annular portion, and a plurality of connecting portions that connect the inner annular portion and the outer annular portion is provided. A non-pneumatic tire manufacturing method comprising:
A middle mold for molding the inner peripheral side of the inner annular part, an outer mold for molding the outer peripheral side of the outer annular part, and a circumferential direction between the middle mold and the outer mold, A plurality of cores for forming the outer peripheral side, the inner peripheral side of the outer annular portion, and the connecting portion; a pair of upper molds and lower molds for molding both side surfaces in the tire width direction of the support structure; And forming a cavity corresponding to the inner annular portion, the outer annular portion, and the connecting portion;
Arranging the reinforcing fibers in an annular shape so as to contact the inner peripheral surface of the outer mold;
Supplying a liquid material of an elastic material to the cavity and curing it to mold the support structure;
And a step of joining a belt layer to the outer peripheral side of the molded support structure. The method for manufacturing a non-pneumatic tire according to claim 3, further comprising a step of buffing an outer peripheral surface of the molded support structure after the step of forming the support structure.

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