WO2020066279A1 - Pneu - Google Patents

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Publication number
WO2020066279A1
WO2020066279A1 PCT/JP2019/029952 JP2019029952W WO2020066279A1 WO 2020066279 A1 WO2020066279 A1 WO 2020066279A1 JP 2019029952 W JP2019029952 W JP 2019029952W WO 2020066279 A1 WO2020066279 A1 WO 2020066279A1
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WO
WIPO (PCT)
Prior art keywords
tire
bead
straight line
point
width direction
Prior art date
Application number
PCT/JP2019/029952
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English (en)
Japanese (ja)
Inventor
高山　佳久
Original Assignee
株式会社ブリヂストン
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Filing date
Publication date
Application filed by 株式会社ブリヂストン filed Critical 株式会社ブリヂストン
Publication of WO2020066279A1 publication Critical patent/WO2020066279A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C15/00—Tyre beads, e.g. ply turn-up or overlap
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
    • B60C9/02—Carcasses
    • B60C9/04—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship
    • B60C9/08—Carcasses the reinforcing cords of each carcass ply arranged in a substantially parallel relationship the cords extend transversely from bead to bead, i.e. radial ply

Definitions

  • the present invention relates to a tire having a simplified bead structure.
  • an object of the present invention is to provide a tire that can secure sufficient steering stability even when the structure of a bead portion is simplified.
  • the tire (pneumatic tire 10) includes a tread portion (tread portion 20) in contact with a road surface, and a tire side portion (tire side portion) connected to the tread portion and located inside the tread portion in the tire radial direction. 30), a bead portion (bead portion 60) connected to the tire side portion and located inside the tire side portion in the tire radial direction, and a carcass (carcass 40) forming a skeleton of the tire.
  • the bead portion has an annular bead core (bead core 200) extending in the circumferential direction of the tire, and an outer surface portion (outer surface portion 61) in contact with a rim flange (rim flange 110) of a rim wheel (rim wheel 100) to be assembled to the tire.
  • the carcass has a main body (main body 41) and a folded part (returned part 42) connected to the main body and folded outward in the tire width direction via a bead core. No bead filler is interposed between the main body portion and the folded portion.
  • a position on the tire equator line in the tread portion is point A
  • a tire maximum width position is point B
  • a virtual straight line parallel to the tire width direction passing through point A is point L1 and point B.
  • L2 a virtual straight line parallel to the tire width direction passing through the middle between the virtual straight line L1 and the virtual straight line L2, and a point C at the intersection of the virtual straight line L3 and the carcass.
  • L4 is a virtual straight line that is parallel to the tire radial direction passing through C
  • L5 is a virtual straight line that is in contact with the carcass at point C
  • D is the point of the radially outer end of the outer surface portion
  • D passes point D, and is perpendicular to the outer surface portion.
  • the intersection of the virtual perpendicular L6 and the turn-back portion is point E
  • the virtual straight line contacting the turn-back portion at the point E is L7
  • the angle between the virtual straight line L4 and the virtual straight line L5 is 30 Degree-7 Every time it is.
  • the angle between the virtual straight line L7 and the bead base line parallel to the tire width direction passing through the rim diameter position of the rim wheel is 50 to 80 degrees.
  • FIG. 1 is a cross-sectional view of a pneumatic tire along a tire width direction and a tire radial direction.
  • FIG. 2 is an enlarged sectional view of a rim wheel and a bead portion.
  • FIG. 3 is a graph showing an evaluation test result of the steering stability of a bead fillerless tire.
  • FIG. 4A is a cross-sectional view along the tire width direction and the tire radial direction of the pneumatic tire.
  • FIG. 4B is an enlarged sectional view of the rim wheel and the bead portion.
  • FIG. 5 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 1 is a cross-sectional view of a pneumatic tire along a tire width direction and a tire radial direction.
  • FIG. 2 is an enlarged sectional view of a rim wheel and a bead portion.
  • FIG. 3 is a graph showing an evaluation test result of the
  • FIG. 6 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 7 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 8 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 9 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 10 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 11 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 12 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 13 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 14 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 15 is a cross-sectional view along a tire width direction and a tire radial direction of a pneumatic tire according to another embodiment of the present invention.
  • FIG. 16 is an enlarged sectional view of a rim wheel and a bead portion according to another embodiment of the present invention.
  • FIG. 1 is a partial cross-sectional view of a pneumatic tire 10 according to the present embodiment. Specifically, FIG. 1 is a cross-sectional view of the pneumatic tire 10 along the tire width direction and the tire radial direction. FIG. 1 shows only one side based on the tire equator line CL. In FIG. 1, illustration of cross-sectional hatching is omitted (the same applies hereinafter).
  • the pneumatic tire 10 includes a tread portion 20, a tire side portion 30, a carcass 40, a belt layer 50, and a bead portion 60.
  • the tread portion 20 is a portion in contact with a road surface (not shown).
  • the tire side portion 30 is continuous with the tread portion 20 and is located inside the tread portion 20 in the tire radial direction.
  • the tire side portion 30 is a region from the outer end in the tire width direction of the tread portion 20 to the upper end of the bead portion 60.
  • the tire side part 30 may be called a sidewall or the like.
  • the carcass 40 forms the skeleton of the pneumatic tire 10.
  • the carcass 40 has a radial structure having carcass cords (not shown) radially arranged along the tire radial direction.
  • the carcass 40 is not limited to the radial structure, and may be a bias structure in which carcass cords are arranged so as to intersect in the tire radial direction.
  • the belt layer 50 is provided inside the tread portion 20 in the tire radial direction.
  • the belt layer 50 includes a pair of intersecting belts in which cords intersect, and a reinforcing belt provided on the tire radial outside of the intersecting belt.
  • the reinforcing belt is sometimes called a cap & layer.
  • the belt layer 50 may include a reinforcing belt having a shape different from that of the cap & layer.
  • the bead portion 60 continues to the tire side portion 30 and is located inside the tire side portion 30 in the tire radial direction.
  • the bead portion 60 has an annular shape, and the carcass 40 is folded back from the inner side in the tire width direction to the outer side in the tire width direction via the bead portion 60.
  • the pneumatic tire 10 has substantially the same structure as a tire mounted on a general passenger car (including a minivan and an SUV (Sport Utility Vehicle)).
  • the bead portion 60 is not provided with a bead filler.
  • the bead filler is also called a stiffener, and is formed of a material such as rubber that is harder than the other parts of the rubber.
  • the bead filler is generally provided for the purpose of improving the rigidity of the bead portion 60.
  • the pneumatic tire 10 is for a passenger car, and particularly preferably satisfies the following specifications.
  • the pneumatic tire 10 has a tire size as shown in Table 1.
  • the size is not limited to this, and other tire sizes may be used as long as the above-described specifications are satisfied.
  • the pneumatic tire 10 is assembled to the rim wheel 100. Specifically, the bead portion 60 is engaged with a rim flange 110 (not shown in FIG. 1, see FIG. 2) formed at a radially outer end of the rim wheel 100.
  • the pneumatic tire 10 is a tire in which air is filled in an internal space formed by being assembled to the rim wheel 100.
  • the gas filled in the internal space is not limited to air, but may be nitrogen gas or the like. Inert gas may be used.
  • Point A shown in FIG. 1 is a position on the tire equator line CL in the tread portion 20.
  • Point B is the tire maximum width position.
  • the tire maximum width position is the maximum width position of the pneumatic tire 10 at which the width along the tire width direction is maximum.
  • L1 is a virtual straight line passing through the point A and parallel to the tire width direction.
  • L2 is a virtual straight line passing through the point B and parallel to the tire width direction.
  • L3 is a virtual straight line parallel to the tire width direction passing between the virtual straight line L1 and the virtual straight line L2.
  • Point C is the intersection of virtual line L3 and carcass 40. Specifically, the point C is located on the carcass 40 on the outer side in the tire radial direction.
  • L4 is a virtual straight line passing through the point C and parallel to the tire radial direction.
  • L5 is a virtual straight line that contacts the carcass 40 at the point C.
  • the angle ⁇ 1 between the virtual straight line L4 and the virtual straight line L5 is 30 degrees to 70 degrees.
  • the angle ⁇ 1 is not limited to this. Angle ⁇ 1 may be between 40 and 65 degrees.
  • FIG. 2 is an enlarged sectional view of the rim wheel 100 and the bead portion 60. Specifically, FIG. 2 is a cross-sectional view of the bead portion 60 (and the rim wheel 100) along the tire width direction and the tire radial direction.
  • the carcass 40 is folded outward in the tire width direction via the bead portion 60.
  • the carcass 40 includes a main body 41 and a turnback 42.
  • the main body 41 is provided over the tread portion 20, the tire side portion 30 (see FIG. 1) and the bead portion 60, and is a portion until the bead portion 60 is folded back.
  • the folded portion 42 is a portion that continues to the main body portion 41 and is folded outward in the tire width direction via the bead core 200.
  • the bead core 200 is a ring-shaped member extending in the tire circumferential direction, and is formed of a metal (steel) cord.
  • the rim line 65 is a protrusion formed along the tire circumferential direction to check whether the bead portion 60 is correctly mounted on the rim wheel 100.
  • the rim line 65 is provided about 6 mm outside the radially outer end of the rim flange 110 in the tire radial direction.
  • the bead portion 60 has no bead filler. Specifically, no bead filler is interposed between the body portion 41 of the carcass 40 folded back via the bead core 200 and the folded portion 42.
  • the space surrounded by the main body portion 41, the folded portion 42, and the bead core 200 is basically an air gap, but may be interposed in the vulcanizing step of the pneumatic tire 10 with rubber that has entered from around the space. Good. The rubber entering from the surroundings has lower rigidity than rubber used as a bead filler.
  • the physical properties of the rubber entering the space are preferably such that the 300% modulus (M300) is 5 MPa or more and 20 MPa or less. For example, such properties can be achieved by the ply coating rubber entering the space.
  • the bead portion 60 has an outer surface portion 61 that comes into contact with the rim flange 110.
  • the outer surface portion 61 is a part of the tire outer surface of the bead portion 60.
  • the outer surface portion 61 is curved so as to be depressed inward in the tire width direction in the cross section of the bead portion 60 along the tire width direction and the tire radial direction.
  • Point D shown in FIG. 2 is the position of the outer end of the outer surface portion 61 in the tire radial direction.
  • the point D is a separation point located on the outer surface of the pneumatic tire 10 where the outer surface portion 61 is separated from the state of contact with the rim flange 110.
  • L6 is an imaginary perpendicular passing through the point D and crossing the outer surface 61 at right angles.
  • the point E is the intersection of the virtual perpendicular line L6 and the folded portion 42.
  • L7 is an imaginary straight line that is in contact with the folded portion 42 at the point E.
  • BL is a straight line (bead base line) that passes through the rim diameter position of the rim wheel 100 and is parallel to the tire width direction.
  • the angle ⁇ 2 between the virtual straight line L7 and the bead base line BL is 50 to 80 degrees.
  • the angle ⁇ 2 is not limited to this.
  • the angle ⁇ 2 may be 60 to 78 degrees, or may be 65 to 75 degrees.
  • FIG. 3 is a graph showing an evaluation test result of steering stability of a bead fillerless tire. Specifically, FIG. 3 shows evaluation test results of a general pneumatic tire provided with a bead filler (conventional example) and a bead filler-less tire (comparative example).
  • the bead filler-less tire (comparative example) shown in FIG. 3 is different from the pneumatic tire 10 according to the present embodiment described above, except that no bead filler is provided. It has a similar configuration.
  • a single lane change (severe) satisfies the following conditions.
  • ⁇ Entry speed 100km / h
  • Horizontal G 0.5 to 0.6 -Number of lane changes: 1 lane-Lane change time: 2 seconds
  • FIG. 3 shows the steering angle of the steering wheel of the vehicle and the yaw angle generated in the vehicle for each of the conventional example and the comparative example.
  • the driver starts the operation of returning the steering wheel ((2) in the figure).
  • the holding time at the steering angle is long. That is, in the comparative example, it takes a longer distance (time) than the conventional example until the vehicle reaches a certain yaw angle.
  • the angle ⁇ 1 between the virtual straight line L4 and the virtual straight line L5 is 30 degrees to 70 degrees.
  • the angle ⁇ 2 between the virtual straight line L7 and the bead base line BL is 50 to 80 degrees. It has been found that even when the bead filler is omitted, the fall of the bead portion 60 near the rim flange 110 is suppressed if the angles ⁇ 1 and ⁇ 2 are the above. That is, the pneumatic tire 10 having the angles ⁇ 1 and ⁇ 2 can secure sufficient steering stability even when the structure of the bead portion 60 is simplified. The same effect can be obtained even when the angle ⁇ 1 is 40 to 65 degrees. The same effect can be obtained even when the angle ⁇ 2 is 60 to 78 degrees or 65 to 75 degrees.
  • the distance Q from the point D to the point E shown in FIG. 2 may be 2 to 7 mm. Thereby, a similar effect can be obtained.
  • the pneumatic tire 10 may include a bead filler sheet 400.
  • the bead filler sheet 400 is provided outside the carcass 40 in the tire width direction.
  • the bead filler sheet 400 is provided along the carcass 40 outside the bead core 200 in the tire radial direction and outside the carcass 40 in the tire width direction.
  • a radially inner portion of the bead filler sheet 400 is in contact with the folded portion 42, and a radially outer portion of the bead filler sheet 400 is in contact with the main body 41. That is, the bead filler sheet 400 is provided so as to cover the radially outer end of the folded portion 42.
  • the tire radial outer end 401 of the bead filler sheet 400 may be located radially inward in the tire radial direction from the maximum width position of the pneumatic tire 10 in which the width along the tire width direction is maximum.
  • the tire radial direction inner end 403 of the bead filler sheet 400 may be located outside the tire radial direction inner end of the bead core 200 in the tire radial direction in the tire radial direction.
  • the bead filler sheet 400 is provided between the tire radial inner end of the bead core 200 and the maximum width position in the tire radial direction.
  • the length of the bead filler sheet 400 when the length from point A to the tire radial inner end 60 a of the bead portion 60 is T, the length of the bead filler sheet 400, that is, the tire radial outer side of the bead filler sheet 400.
  • the length along the bead filler sheet 400 from the end 401 to the tire radial inner end 403 is preferably 0.1 T or more and 0.5 T or less.
  • the thickness of the bead filler sheet 400 is preferably 0.2 mm or more and 2.5 mm or less.
  • the physical properties of the bead filler sheet 400 preferably have a 50% modulus (M50) of 3 MPa or more and 15 MPa or less.
  • the bead core embedded in the bead portion 60 may fill a space formed between the main body portion 41 and the folded portion 42.
  • the folded portion 42 has a contact region CR that is in contact with the main body 41 on the outer side in the tire radial direction.
  • the tire radial inner end CR1 of the contact region CR is provided near a position facing the rim flange 110.
  • rubber may be interposed between the main body 41 and the folded portion 42, and the main body 41 and the folded portion 42 may be provided in parallel with each other.
  • the bead core 250 is interposed in a space formed between the main body 41 of the carcass 40 and the turnback 42.
  • Bead core 250 includes a core section 260 and a tapered section 270.
  • the folded portion 42 is folded outward in the tire width direction via the core portion 260.
  • the tapered portion 270 is located outside the core portion 260 in the tire radial direction, and is provided integrally with the core portion 260.
  • the tapered portion 270 becomes narrower in the cross section along the tire radial direction and the tire width direction from the core portion 260 toward the radially inner end CR1 of the contact region CR.
  • Tapered portion 270 has an inner portion 272 and an outer portion 274.
  • the inner portion 272 is located inside the tapered portion 270 in the tire width direction, and is provided in parallel with the longitudinal direction LD1 of the bead core 250.
  • the outer portion 274 is located outside the tapered portion 270 in the tire width direction.
  • the outer portion 274 is inclined with respect to the longitudinal direction LD1 of the bead core 250 toward the tire radial inner end CR1 of the contact region CR.
  • the main body 41 contacts the inner part 272.
  • the folded portion 42 of the carcass 40 contacts the outer portion 274.
  • no bead filler is interposed between the main body portion 41 and the folded portion 42 of the carcass 40. Thereby, the structure of the bead portion 60 is simplified, and the weight of the tire is reduced.
  • the bead filler sheet 400 is provided along the carcass 40 outside the bead core 250 in the tire radial direction.
  • the bead core 250 has a tapered portion 270 that becomes thinner toward the tire radial direction inner end CR1 of the contact region CR in a cross section along the tire radial direction and the tire width direction.
  • the folded portion 42 of the carcass 40 contacts the tapered portion 270.
  • the radius of curvature R of the outer surface portion 61 shown in FIG. 5 may be set to 30 mm or more and 300 mm or less. Further, the radius of curvature R may be set to 50 mm or more and 200 mm or less.
  • the radius of curvature R is the arc of a circular arc passing through the position of the outer surface portion 61 with respect to the center located outside the bead portion 60 in the tire width direction in the cross section of the bead portion 60 along the tire width direction and the tire radial direction. Radius.
  • the radius of curvature R is based on the position of an outer end (point D) of the outer surface portion 61 in the tire radial direction.
  • the outermost surface of the bead portion 60 in contact with the rim flange 110 in the tire radial direction means the outermost position in the tire radial direction.
  • the radius of curvature R is based on the shape of the pneumatic tire 10 that is not mounted on the rim wheel 100 and is not loaded.
  • the radius of curvature R is the length of the portion having each curvature. May be expressed as an average of the plurality of radii of curvature.
  • the outer surface portion 61 has such a curvature, the load applied to the bead portion 60 near the rim flange 110 is dispersed, and the bead portion 60 can be prevented from falling down. As a result, the roll amount and swingback of the vehicle are reduced. That is, the steering stability of the vehicle equipped with the pneumatic tire 10 can be ensured.
  • the rubber gauge at the position of point D (outer end in the tire radial direction), specifically, the thickness from point D to the outer end in the tire width direction of folded portion 42 (including bead filler sheet 400). Is preferably 3.5 mm or more and 9.5 mm.
  • the bead core 250a may include a core portion 260a and a tapered portion 270a.
  • the core portion 260a has an outer portion 264a located on the outer side in the tire width direction.
  • the outer portion 264a is inclined with respect to the longitudinal direction LD2 of the bead core 250a toward the tire radial inner end CR1 of the contact region CR.
  • the tapered portion 270a has an outer portion 274a located outside in the tire width direction.
  • the outer portion 274a is inclined with respect to the longitudinal direction LD2 of the bead core 250a toward the tire radial inner end CR1 of the contact region CR.
  • the outer portion 264a of the core portion 260a and the outer portion 274a of the tapered portion 270a are connected in a straight line to form the outer portion 252a of the bead core 250a.
  • the outer surface of the bead core 250a in the tire width direction is formed flush.
  • the bead core 250b may include a core 260b and a tapered portion 270b.
  • the core 260b of the bead core 250b is similar to the core 260 of the bead core 250.
  • the tapered portion 270b becomes thinner toward the tire radial direction inner end CR1 of the contact region CR in a cross section along the tire radial direction and the tire width direction.
  • Tapered portion 270b has an inner portion 272b and an outer portion 274b.
  • the inner portion 272b is located inside the tapered portion 270b in the tire width direction.
  • the inner portion 272b is inclined with respect to the longitudinal direction LD3 of the bead core 250b toward the tire radially inner end CR1 of the contact region CR.
  • the outer portion 274b is located outside the tapered portion 270b in the tire width direction.
  • the outer portion 274b is inclined with respect to the longitudinal direction LD3 of the bead core 250b toward the tire radially inner end CR1 of the contact region CR.
  • the main body 41 of the carcass 40 contacts the inner part 272b.
  • the folded portion 42 of the carcass 40 contacts the outer portion 274b.
  • the main body portion 41 and the folded portion 42 of the carcass 40 are pressed from the inside in the tire width direction and the outside in the tire width direction, and come into contact with the tapered portion 270 of the bead core 250. . Thereby, the rigidity near the rim flange 110 becomes higher, and the steering stability is maintained.
  • the shape of the bead core is not limited to the shapes shown in FIGS.
  • the shape of the bead core may be the shape shown in FIG.
  • the bead core 205 includes an inner bead core 210 provided on the inner side in the tire width direction and an outer bead core 220 provided on the outer side in the tire width direction.
  • the inner bead core 210 is provided inside the carcass 40 in the tire width direction, and the outer bead core 220 is provided outside the carcass 40 in the tire width direction.
  • the inner bead core 210 is constituted by two ring-shaped members in which a plurality of cords are twisted and whose cross-sectional shape is circular.
  • the two ring-shaped members are provided along the tire radial direction.
  • the outer bead core 220 is also formed of two ring-shaped members having a plurality of twisted cords and a circular cross section.
  • the two ring-shaped members are also provided along the tire radial direction.
  • the carcass 40 is interposed between the inner bead core 210 and the outer bead core 220.
  • the tire radial inner end 40 a of the carcass 40 extends to the tire radial inner end 210 a of the inner bead core 210 and the tire radial inner end 220 a of the outer bead core 220.
  • the inner bead core 210 and the outer bead core 220 sandwich the carcass 40 extending to the tire radial inner end 210a and the tire radial inner end 220a. Specifically, the inner bead core 210 contacts the outer surface of the carcass 40 in the tire width direction, and the outer bead core 220 contacts the inner surface of the carcass 40 in the tire width direction.
  • the bead filler sheet 400 is provided along the carcass 40 outside the bead core 205 in the tire radial direction and outside the carcass 40 in the tire width direction.
  • the bead core 205 of the bead portion 60 shown in FIG. 8 is constituted by the inner bead core 210 and the outer bead core 220.
  • the carcass 40 is interposed between the inner bead core 210 and the outer bead core 220. That is, the carcass 40 is not folded back via the bead core 205 unlike a general tire, and the bead portion 60 is not provided with a bead filler. For this reason, the gauge of the bead part 60 can be made thin.
  • the bead filler sheet 400 is provided along the carcass 40 outside the carcass 40 in the tire width direction. For this reason, the bead filler sheet 400 can support the load applied to the bead portion 60 and suppress the bead portion 60 from falling down. That is, the steering stability of the vehicle equipped with the pneumatic tire 10 can be ensured.
  • the tire radial inner end 40a of the carcass 40 shown in FIG. 8 extends at the tire radial inner end 210a of the inner bead core 210 or the tire radial inner end 220a of the outer bead core 220.
  • the inner bead core 210 and the outer bead core 220 sandwich the carcass 40. Therefore, the carcass 40 can be reliably interposed between the inner bead core 210 and the outer bead core 220, and the rigidity of the bead portion 60 can be improved. This can contribute to further improvement of the steering stability of the vehicle.
  • the bead core 205A may be configured by the inner bead core 210 and the outer bead core 220A.
  • the outer bead core 220A is constituted by three ring-shaped members. That is, like the bead core 205A, the inner bead core and the outer bead core do not necessarily have to have the same shape (symmetric shape). Specifically, the number of ring-shaped members forming the inner bead core may be different from the number of ring-shaped members forming the outer bead core.
  • the bead core 205B may be configured by the inner bead core 210 and the outer bead core 220B.
  • the outer bead core 220B is provided outside the inner bead core 210 in the tire radial direction. That is, like the bead core 205B, the inner bead core and the outer bead core need not always be provided at the same position in the tire radial direction.
  • the tire radial inner end 40a of the carcass 40 is located radially inward of the outer bead core 220B.
  • the tire radial direction inner end 40a of the carcass 40 may be located radially inward of the tire radial direction inner ends of the inner bead core and the outer bead core, or the tire of either the inner bead core or the outer bead core. It may be located radially inward of the radially inner end.
  • the tire radially inner end 40a of the carcass 40 may be located radially outward of the tire radially inner end of at least one of the inner bead core and the outer bead core.
  • the bead filler sheet 400 may be provided along the carcass 40 and at the outside of the carcass in the tire width direction on at least one of the inner bead core and the outer bead core in the tire radial direction. That is, the bead filler sheet 400 may be provided so as to overlap any one of the bead cores in the tire radial direction.
  • the bead portion 60 may have the configuration shown in FIG. As shown in FIG. 11, the bead core 280 is interposed in a space formed between the main body 41 of the carcass 40 and the folded portion 42. Bead core 280 includes a core 282 and a protrusion 284. The folded portion 42 is folded outward through the core portion 282 in the tire width direction.
  • the convex portion 284 is located outside the core portion 282 in the tire radial direction, and is provided integrally with the core portion 282.
  • the convex portion 284 projects from the core portion 282 toward a space formed between the main body portion 41, the folded portion 42, and the core portion 282 in a cross section along the tire radial direction and the tire width direction.
  • the protrusion 284 has an inner portion 286 and an outer portion 288.
  • the inner portion 286 is located inside the protrusion 284 in the tire width direction, and is provided in parallel with the longitudinal direction LD1 of the bead core 280.
  • the outer portion 288 is located outside the protrusion 284 in the tire width direction.
  • the outer portion 288 is inclined toward the radially outer end of the inner portion 286 with respect to the longitudinal direction LD1 of the bead core 280.
  • the main body 41 of the carcass 40 contacts the inner part 286.
  • the folded portion 42 of the carcass 40 contacts a part of the outer portion 288.
  • the outer peripheral surface of bead core 280 is covered with wrapping member 290.
  • the wrapping member 290 is made of, for example, vinylon cord.
  • the inner portion 286 and the outer portion 288 of the projection 284 include a wrapping member 290.
  • the wrapping member 290 may not be provided on the outer peripheral surface of the bead core 280. In this case, the inner portion 286 and the outer portion 288 of the projection 284 do not include the wrapping member 290.
  • the filling section 300 fills a space formed between the main body section 41 of the carcass 40, the folded section 42, and the convex section 284 of the bead core 280.
  • the filling section 300 is made of rubber that is harder than the other parts of the rubber.
  • the inner end in the tire radial direction of the contact area where the folded portion 42 contacts the main body 41 is provided near the position facing the rim flange 110.
  • the ratio of the area of the filling portion 300 to the area of the bead core 280 is set to 5% or more and 95% or less.
  • the ratio of the area of the filling portion 300 to the area of the bead core 280 is set to 10% or more and 90% or less. More preferably, the ratio of the area of the filling section 300 to the area of the bead core 280 is set to 20% or more and 85% or less.
  • the area of the bead core 280 is set to 6 mm 2 or more and 70 mm 2 or less, but is not limited thereto.
  • the area of bead core 280 may be set to 10 mm 2 or more and 50 mm 2 or less, or may be set to 25 mm 2 or more and 45 mm 2 or less.
  • the area of the filling portion 300 is set to 3 mm 2 or more and 40 mm 2 or less, but is not limited to this.
  • the area of the filling section 300 may be set to 5 mm 2 or more and 30 mm 2 or less, or may be set to 10 mm 2 or more and 20 mm 2 or less.
  • the protrusion 284 of the bead core 280 fills a part of the space, and the filling part 300 fills the remaining part of the space.
  • the filling portion may be formed by a wrapping member 290 covering the outer peripheral surface of the bead core 280 instead of the hard rubber.
  • the wrapping member 290 fills a space formed between the main body portion 41 of the carcass 40, the folded portion 42, and the convex portion 284. Since the wrapping member 290 covering the outer peripheral surface of the bead core 280 can be used as the filling portion, it is not necessary to prepare a separate hard rubber, and the manufacturing process of the pneumatic tire 10 can be simplified.
  • the folded portion 42 of the carcass 40 may not be in contact with the convex portion 284 of the bead core 280.
  • the filling part 310 fills a space formed between the main body part 41, the folded part 42, and the convex part 284.
  • the folded portion 42 may be distorted.
  • the occurrence of distortion can be suppressed by interposing the filling portion 310 between the folded portion 42 and the convex portion 284.
  • a decrease in rigidity near the rim flange 110 can be avoided.
  • bead core 280a may include core portion 282a and convex portion 284a.
  • the core 282a is similar to the core 282 shown in FIG.
  • the convex portion 284a projects from the core portion 282a toward a space formed between the main body portion 41, the folded portion 42, and the core portion 282a.
  • the protrusion 284a has an inner portion 286a and an outer portion 288a.
  • the inner portion 286a is located inside the protrusion 284a in the tire width direction.
  • the inner portion 286a is inclined toward the radially outer end of the bead core 280a with respect to the longitudinal direction LD2 of the bead core 280a.
  • the outer portion 288a is located outside the protrusion 284a in the tire width direction.
  • the outer portion 288a is inclined toward the radially outer end of the bead core 280a with respect to the longitudinal direction LD2 of the bead core 280a.
  • the main body 41 is not in contact with the inner portion 286a.
  • the folded portion 42 of the carcass 40 contacts the outer portion 264b.
  • the filling portion 320 fills a space formed between the main body portion 41 of the carcass 40, the folded portion 42, and the convex portion 284a of the bead core 280a.
  • the folded portion 42 may be distorted.
  • the occurrence of distortion can be suppressed by interposing the filling portion 310 between the folded portion 42 and the convex portion 284.
  • a decrease in rigidity near the rim flange 110 can be avoided.
  • a tire gauge thickness or the like may be set.
  • Point J shown in FIG. 15 is the end of the belt 50c provided on the outermost side in the tire radial direction of the belt layer 50, on the outer side in the tire width direction.
  • L10 is a virtual straight line passing through the point J and parallel to the tire radial direction.
  • Point N is the intersection of virtual line L1 and virtual line L2.
  • X is the distance from point A to point N.
  • Y is the distance from point N to point J.
  • L11 is an imaginary perpendicular passing through the point J and crossing the tire outer surface at a right angle.
  • Point K is the intersection of virtual perpendicular L11 and the tire outer surface.
  • the distance U from the point J to the point K is 2 to 10 mm.
  • the distance U is not limited to this.
  • the distance U may be 2.5 to 9 mm or 3 to 8 mm.
  • the ratio Y / X between the distance Y and the distance X is 0.03 to 0.25.
  • the ratio Y / X is not limited to this.
  • the ratio Y / X may be between 0.05 and 0.20.
  • bead core 280b may include core portion 282b and convex portion 284b.
  • the core portion 282b has an outer portion 282b1 located on the outer side in the tire width direction.
  • the outer portion 282b1 is inclined toward the radially outer end of the bead core 280b with respect to the longitudinal direction LD3 of the bead core 280b.
  • the convex portion 284b projects from the core portion 282b toward a space formed between the main body portion 41 of the carcass 40, the folded portion 42, and the core portion 282b of the bead core 280b.
  • the convex portion 284b has an outer portion 284b1 located outside in the tire width direction.
  • the outer portion 284b1 is inclined toward the radially outer end of the bead core 280b with respect to the longitudinal direction LD3 of the bead core 280b.
  • the outer portion 282b1 of the core portion 282b and the outer portion 284b1 of the convex portion 284b are linearly connected to form an outer portion 280b1 of the bead core 280b.
  • the outer surface of the bead core 280b in the tire width direction is formed flush.
  • the folded portion 42 of the carcass 40 does not contact a part of the outer portion 284b1 of the convex portion 284b.
  • the filling part 330 fills a space formed between the main body part 41 of the carcass 40, the folded part 42, and the convex part 284b of the bead core 280b.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Tires In General (AREA)

Abstract

Dans une section transversale le long de la direction de la largeur du pneu et de la direction radiale du pneu, l'angle θ1 formé par la ligne droite imaginaire L4 et la droite imaginaire L5 est dans la plage de 30 à 70 degrés, où le point A est la position sur la ligne équatoriale de pneu CL dans une partie bande de roulement (20), le point B est la position de largeur maximale de pneu, L1 est une ligne droite imaginaire parallèle à la direction de la largeur du pneu passant à travers le point A, L2 est une ligne droite imaginaire parallèle à la direction de la largeur du pneu passant par le point B, L3 est une ligne droite imaginaire parallèle à la direction de la largeur du pneu passant à travers une partie intermédiaire entre la ligne droite imaginaire L1 et la ligne droite imaginaire L2, le point C est l'intersection entre la ligne droite imaginaire L3 et une carcasse (40), L4 est une ligne droite imaginaire parallèle à la direction radiale du pneu passant par le point C, et L5 est la ligne droite imaginaire tangente à la carcasse (40) au point C.
PCT/JP2019/029952 2018-09-28 2019-07-31 Pneu WO2020066279A1 (fr)

Applications Claiming Priority (2)

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JP2018185242A JP7088802B2 (ja) 2018-09-28 2018-09-28 タイヤ
JP2018-185242 2018-09-28

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WO2020066279A1 true WO2020066279A1 (fr) 2020-04-02

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09109625A (ja) * 1995-10-24 1997-04-28 Yokohama Rubber Co Ltd:The 空気入りタイヤ
JP2000335207A (ja) * 1999-05-06 2000-12-05 Dunlop Tire Corp 空気入りタイヤ
JP2008155728A (ja) * 2006-12-22 2008-07-10 Sumitomo Rubber Ind Ltd 空気入りタイヤ
JP2013063679A (ja) * 2011-09-15 2013-04-11 Bridgestone Corp 空気入りタイヤ
WO2015097925A1 (fr) * 2013-12-27 2015-07-02 株式会社ブリヂストン Pneumatique
JP2018103760A (ja) * 2016-12-26 2018-07-05 東洋ゴム工業株式会社 空気入りタイヤ

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5829632B2 (ja) * 2013-01-22 2015-12-09 株式会社ブリヂストン 空気入りタイヤ

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09109625A (ja) * 1995-10-24 1997-04-28 Yokohama Rubber Co Ltd:The 空気入りタイヤ
JP2000335207A (ja) * 1999-05-06 2000-12-05 Dunlop Tire Corp 空気入りタイヤ
JP2008155728A (ja) * 2006-12-22 2008-07-10 Sumitomo Rubber Ind Ltd 空気入りタイヤ
JP2013063679A (ja) * 2011-09-15 2013-04-11 Bridgestone Corp 空気入りタイヤ
WO2015097925A1 (fr) * 2013-12-27 2015-07-02 株式会社ブリヂストン Pneumatique
JP2018103760A (ja) * 2016-12-26 2018-07-05 東洋ゴム工業株式会社 空気入りタイヤ

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JP2020055340A (ja) 2020-04-09

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