Non-pneumatic tires

Abstract

The present invention discloses a non-pneumatic tire and wheel assembly, comprising: a wheel, the wheel having a first steel wire ring and a second steel wire ring; a non-pneumatic tire, the non-pneumatic tire having a shear band and a tread forming a tread band, and a first sidewall area and a second sidewall area; wherein the first sidewall area and the second sidewall area each extend from the tread band and terminate in a corresponding first bead area and a second bead area, wherein the first bead area and the second bead area are each mounted on the first steel wire ring and the second steel wire ring, respectively; wherein when mounted on the wheel, each bead area is located axially outside the crown area of ​​the non-pneumatic tire, and wherein the first sidewall and the second sidewall each have an upper sidewall area that is not connected to the outer lateral end of the tread band.

Description

Technical Field

[0001] The present invention relates generally to vehicle tires and, more particularly, to non-pneumatic tires. Background Art

[0002] For more than a century, pneumatic tires have been the solution of choice for vehicle mobility. Pneumatic tires are tensile structures. Pneumatic tires have at least four properties that make pneumatic tires so dominant today. Pneumatic tires are efficient in carrying loads, as all tire structures involve carrying loads. Pneumatic tires are also desirable because they have low contact pressure, resulting in lower wear on the road due to vehicle load distribution. Pneumatic tires also have low stiffness, which ensures a comfortable ride in the vehicle. The main disadvantage of a pneumatic tire is that it requires compressed fluid. A conventional pneumatic tire becomes useless after a complete loss of inflation pressure.

[0003] A tire designed to operate without inflation pressure would eliminate many of the problems and compromises associated with pneumatic tires. Neither pressure maintenance nor pressure monitoring would be required. Structural support tires, such as solid tires or other elastomeric structures, have not, to date, provided the level of performance required from conventional pneumatic tires. A structural support tire solution that provided pneumatic tire-like performance would be a desired improvement.

[0004] Non-pneumatic tires are often defined by their load carrying efficiency. A "bottom loader" is an essentially rigid structure that carries most of the load in the structural portion below the wheel hub. A "top loader" is designed so that all of the structure participates in carrying the load. Therefore, a top loader has a higher load carrying efficiency than a bottom loader, allowing a design with less mass.

[0005] Therefore, an improved non-pneumatic tire is desired that has all of the features of a pneumatic tire without the disadvantages of requiring inflation. Summary of the invention

[0006] The present invention provides a non-pneumatic tire and wheel assembly in a first aspect, comprising: a wheel having a first steel wire ring and a second steel wire ring; a non-pneumatic tire having a shear band and a tread forming a tread band, and a first sidewall area and a second sidewall area; wherein the first sidewall area and the second sidewall area each extend from the tread band and terminate in a corresponding first bead area and a second bead area, wherein the first bead area and the second bead area are each mounted on the first steel wire ring and the second steel wire ring, respectively; wherein when mounted on the wheel, each bead area is located axially outside the crown area of ​​the non-pneumatic tire, and wherein the first sidewall and the second sidewall each have an upper sidewall area that is not connected to the outer lateral end of the tread band.

[0007] The present invention provides the following technical solutions:

[0008] 1. A non-pneumatic tire and wheel assembly comprising:

[0009] A wheel having a first bead ring retainer and a second bead ring retainer,

[0010] a non-pneumatic tire having a shear band and a tread forming a tread band, and a first sidewall region and a second sidewall region;

[0011] wherein said first sidewall region and said second sidewall region each extend from said tread band and terminate in respective first and second bead regions,

[0012] wherein a carcass ply extends beneath a crown portion of the non-pneumatic tire and into the first and second sidewall regions and has a first end secured to a first bead region and a second end secured to a second bead region,

[0013] wherein the first bead region and the second bead region are each mounted on the first bead retainer and the second bead retainer; and

[0014] Wherein the carcass ply is tensioned when each bead area is mounted on a corresponding bead retainer of the wheel.

[0015] 2. The non-pneumatic tire and rim assembly of claim 1, wherein the first sidewall and the second sidewall each have an upper sidewall region that is not connected to the outer lateral end of the tread band.

[0016] 3. A non-pneumatic tire and rim assembly according to claim 1, wherein when mounted on the wheel, each bead is tensioned outwardly but axially inward of a corresponding shoulder of the non-pneumatic tire.

[0017] 4. A non-pneumatic tire and rim assembly according to Option 1, wherein when the non-pneumatic tire is not mounted on the wheel and is in an unloaded condition, in an uncoupled position, the carcass ply has a first radius R1 below the crown area of ​​the tread and a second radius R2 in the upper sidewall, and wherein R1 is greater than R2.

[0018] 5. The non-pneumatic tire and rim assembly of claim 1, wherein the shear band is loaded in compression when the non-pneumatic tire is mounted on the wheel.

[0019] 6. The non-pneumatic tire and rim assembly of claim 1, wherein the shear band is circumferentially compressed when the non-pneumatic tire is mounted on the wheel.

[0020] 7. The non-pneumatic tire and rim assembly according to Option 1, wherein the axial distance between the first wire bead and the second wire bead is axially adjustable.

[0021] 8. The non-pneumatic tire and rim assembly of claim 1, wherein each sidewall has at least two layers of reinforcing cord.

[0022] 9. The non-pneumatic tire and rim assembly of claim 1, wherein the first end and the second end of the carcass ply are located in the crown portion of the tire.

[0023] 10. The non-pneumatic tire and rim assembly of claim 1, wherein the sidewall is angled at an angle α relative to a horizontal surface of the rim.

[0024] 11. The non-pneumatic tire and rim assembly of Option 1, wherein each bead area further comprises an apex rubber core.

[0025] 12. The non-pneumatic tire and rim assembly of claim 11, wherein the apex is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289.

[0026] 13. A non-pneumatic tire and rim assembly according to Option 1, wherein each bead area further includes a second apex core, wherein the second apex core is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289.

[0027] 14. A non-pneumatic tire and rim assembly according to Option 1, wherein the lower sidewall portion has a rib reinforcement located axially outside the apex rubber core, and wherein the rib reinforcement is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289.

[0028] 15. A non-pneumatic tire and rim assembly according to Option 1, wherein the lower sidewall portion has a chafer, and wherein the chafer is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be better understood by reference to the following description and accompanying drawings, in which:

[0030] Figure 1 It is mounted on the wheel rim Figure 1 A cross-sectional view of a non-pneumatic tire;

[0031] Figure 2 is a cross-sectional view of a second embodiment of a non-pneumatic tire;

[0032] Figure 3 is shown mounted on a wheel rim Figure 2 a cross-sectional view of a non-pneumatic tire; and

[0033] Figure 4 is a close-up cross-sectional view of one half of a pneumatic tire of the present invention.

[0034] definition

[0035] "Aspect ratio" refers to the ratio of a tire's cross-sectional height to its cross-sectional width.

[0036] "Axial" and "axially" refer to lines or directions parallel to the tire's axis of rotation.

[0037] "Bead" or "bead core" refers generally to that portion of the tire that includes the annular tensile member, the radially inner bead associated with holding the tire to the rim wrapped and shaped by the ply cords, with or without other reinforcing elements such as flippers, chippers, apex cores or fillers, toe guards and chafers.

[0038] “Belt structure” or “reinforcement belt” means at least two annular layers or plies made of parallel cords, woven or non-woven, situated beneath the tread, not anchored to the beads and having left and right cord angles ranging from 17° to 27° with respect to the equatorial plane of the tire.

[0039] "Breaker" or "tire breaker" means the same as belt or belt structure or reinforcing belt.

[0040] "Carcass" refers to the laminate of tire ply material and other tire components, which is cut to length suitable for splicing or has been spliced ​​into a cylindrical or toroidal shape. Additional components may be added to the carcass before it is vulcanized to form a molded tire.

[0041] “Circumferential” means lines or directions extending along the perimeter of the annular tread surface perpendicular to the axial direction; it may also mean the direction of the set of adjacent circular curves whose radii define the axial curvature of the tread, viewed in cross section.

[0042] "Cord" refers to one of the reinforcing strands, including fibers, used to reinforce a ply.

[0043] "Inextensible" means that the cord has a relative elongation at break of less than 0.2% at a load at break of 10% when measured as the cord is extracted from a cured tire.

[0044] “Equatorial plane” means the plane passing through the centerline of the tire and perpendicular to the axis of rotation of the tire.

[0045] “Meridian Plane” means a plane parallel to the tire's axis of rotation and extending radially outward from said axis.

[0046] "Ply" means a cord-reinforced layer of elastomer-coated, radially arranged or otherwise parallel cords.

[0047] "Radial" and "radially" mean directions radially toward or away from the axis of rotation of the tire.

[0048] “Radial ply structure” means that the carcass ply or plies or at least one of the plies has reinforcement cords oriented at an angle between 65° and 90° relative to the equatorial plane of the tire.

[0049] "Radial Ply Tire" means a belted or circumferentially restrained pneumatic tire in which the ply cords extending from bead to bead are laid at cord angles between 65° and 90° relative to the equatorial plane of the tire.

[0050] "Sidewall" means the portion of the tire between the tread and the tire beads.

[0051] "Laminate structure" means an unvulcanized structure made of one or more layers of tire or elastomeric components, such as an innerliner, sidewall, and optional plies. DETAILED DESCRIPTION

[0052] like Figure 1-4 As shown, the non-pneumatic tire 100 of the present invention includes a radially outer ground engaging tread 200 which may be a conventional tread as desired and may include elements such as ribs, blocks, lugs, grooves and sipes as desired to improve the performance of the tire under various conditions.

[0053] In a first embodiment of the shear band 300, the shear band includes at least two inextensible reinforcement layers 310, 320 arranged in parallel and separated by an elastomeric shear matrix 315. Each reinforcement layer 310, 320 may be formed by parallel reinforcement cords embedded in a thin elastomeric coating. The reinforcement cords are preferably inextensible and may be made of steel, aramid, nylon, polyester or other inextensible structures. In the first reinforced elastomeric layer 310, the reinforcement cords are oriented at an angle in the range of 0 to about + / -50 degrees, and more preferably in the range of 0 to + / -10 degrees relative to the tire equatorial plane. In the second reinforced elastomeric layer 320, the reinforcement cords are oriented at an angle in the range of 0 to about + / -50 degrees, and more preferably in the range of 0 to + / -10 degrees relative to the tire equatorial plane. Preferably, the angle of the reinforcement cords of the first layer is in the opposite direction of the angle of the reinforcement cords in the second layer. As shown, the shear band 300 may also optionally include as many additional reinforcement layers 330-360 as possible to achieve the desired stiffness. It is also preferred that the radially outermost reinforcement layers 350, 360 have outer transverse ends 351, 361 having a reduced axial width compared to the radially inner reinforcement layers 310-340.

[0054] The shear matrix layer 315 is located between the first reinforcement layer 310 and the second reinforcement layer 320 and is formed of an elastomeric material having a shear modulus Gm in the range of 0.5 to 10 MPa, and more preferably in the range of 4 to 8 MPa. The thickness of the rubber layer 315 may have a radial thickness in the range of about 0.10 inches to about 0.2 inches, more preferably about 0.15 inches. If additional reinforcement layers 330-360 are utilized, the reinforcement layers are also optionally separated by shear layers 315. The belt layer assembly forms a shear band with the shear layers. The shear band forms an outer annular tread band with the tread.

[0055] like Figure 1 As shown, the non-pneumatic tire 100 of the present invention also includes two axially spaced sidewall portions 400 extending inwardly from the tread to the wheel 50. The central portion of the tread band is within the range of 80-90% of the total axial width of the tread band, while the lateral ends are the remaining margin. The axially outer ends of the tread band are not connected to the carcass.

[0056] The radially innermost end 410 of each sidewall preferably includes an annular bead 420 fixed to the wheel. The non-pneumatic tire 100 also includes a first ply 500 extending from the first bead 420 to the second bead 422. Preferably, the ply 500 includes a reinforcing rubber or ply formed by parallel reinforcing cords of nylon, polyester, aramid or by a combined cord of nylon, polyester or aramid. Preferably, the reinforcement is oriented in a radial direction. The ply extends radially inward from the tread and then wraps around the first bead 420 and has a first end 510 that preferably terminates below the shear band 300, thereby forming an envelope ply. The second end 520 of the ply also extends downward from the tread, wraps around the opposite bead 420, and then preferably terminates below the shear band, thereby forming an envelope ply. Therefore, each sidewall preferably has two effective plies. Alternatively, the first end 510 and the second end 520 may wrap around the bead and terminate radially outward of the tip 432 of the apex 430 .

[0057] Each apex 430 is preferably triangular in shape and has a radial height measured from a first end 431 to a tip 432. The radial height of the outer tip 432 is preferably in the range of ¼ to ¾ of the radial height of the sidewall, and more preferably in the range of 1 / 3 to 2 / 3 of the radial height of the sidewall. Each lower sidewall region, defined as the lower half of the sidewall, is preferably stiffer relative to the stiffness of the upper half of the sidewall. The stiffness of the lower sidewall may be increased by a stiff apex or additional stiff material in the lower sidewall region, such as a chafer or rim flange protector. The additional stiff material may be located on an axially outer portion of the lower sidewall, such as a rim flange protector or chafer, or on an axially inner portion, such as an auxiliary apex.

[0058] Stiffness (i.e., resistance to bending) can be characterized by the dynamic modulus G', which is sometimes referred to as the "shear storage modulus" or "dynamic modulus", see James E. Mark et al., ed., Rubber Science and Technology, 2nd edition, 1994, Academic Press, San Diego, California, pp. 249-254. The shear storage modulus (G') value indicates the stiffness of the rubber compound, which can be related to tire performance. The tan delta value at 100°C is considered to be indicative of hysteresis or heat loss.

[0059] In a first embodiment, the first apex 430 includes a hard rubber composition having a shear storage modulus G' measured at 1% strain and 100° C. according to ASTM D5289 ranging from 14 to 43 MPa. In a more preferred embodiment, the first apex 430 includes a rubber composition having a shear storage modulus G' measured at 1% strain and 100° C. according to ASTM D5289 ranging from 23 to 43 MPa.

[0060] The reinforced lower sidewall ensures that the ply is in tension after mounting on the wheel and also during use. When the ply and the sidewall of the tire are in a relaxed state, the ply line bends so that the bead is located axially inside the shoulder of the tire. When the bead is loaded onto the rim, the curve is straightened and the bead or lower sidewall of the tire moves axially outwards while still preferably remaining within the axial width of the tire shoulder, so that the ply acts as a spring.

[0061] Figure 2 A second embodiment 2000 of the non-pneumatic tire of the present invention is shown mounted on a wheel. By design, the molded ply length is longer than the minimum distance between the molded bead and the shear band. In this design 2000, this is achieved by an increased radius R2 at the top 2450 of the second apex 2400. In this design, the radius R1 under the tread is much larger than the radius R2 at the top of the second apex. This design provides a mechanism that keeps the cord in tension as the shear band deforms into and out of the footprint. The second apex 2400 acts as a spring and provides stiffness to tension the sidewall. The shear band is loaded so that it is circumferentially compressed. This combination of ply geometry will load the shear band uniformly across its width through a range of rim widths and vertical deformations of varying magnitude. In the second embodiment, the first apex 2300 and / or the second apex 2400 each include a hard rubber composition having a shear storage modulus G′ measured at 1% strain and 100° C. according to ASTM D5289 ranging from 14 to 43 MPa, and more preferably ranging from 23 to 43 MPa.

[0062] Figure 3 A tire is shown mounted on a wheel with the plies tensioned in the sidewalls. As shown, the beads seat into L-shaped grooves 900. To pre-tension the plies, the bead retainers of the rim surface 1000 are displaced axially outward until the desired pre-tension is achieved. The tensioning of the ply cords ensures that the tire is 100% a top loader. This is in contrast to a run flat tire where the reinforced sidewall members carry the load because the run flat tire acts as a bottom loader.

[0063] like Figure 3 As shown, after the tire sidewall is pre-tensioned, the shear band plies remain horizontal because the geometry of the ply cord is designed to distribute the compressive shear band load evenly across the full width of the shear band. The deformed shape of the ply cord is between the molded shape and the fully engaged shape. The fully engaged shape is defined as R1 and R3 being minimized to 0 (approaching linear discontinuity), where R2 approaches infinity (linear) Figure 2 The maximum rim axial position will remain at or below this fully engaged ply geometry.

[0064] The stiffness of each sidewall, and more preferably the lower half of the sidewall, contributes to the top loading of the non-pneumatic tire. The lower half of each sidewall is preferably hard and can be reinforced due to a hard apex and / or a hard material block located on the axially outer portion (such as a chafer or a rim flange protector). The sidewall of the tire is pre-tensioned by axially expanding the wheel rim. In a third embodiment, the chafer or rim flange protector located axially outside the apex comprises a hard rubber composition having a shear storage modulus G' measured at 1% strain and 100°C according to ASTM D5289, ranging from 14 to 43 MPa, and more preferably ranging from 23 to 43 MPa.

[0065] Figure 4 An alternative embodiment is shown showing an alternative ply line with less curvature. An alternative embodiment could also have alternating molded holes in 3 dimensions for weight reduction. This would give the appearance of spokes.

[0066] Variations of the present invention are possible according to the description of the present invention provided herein. Although certain representative embodiments and details have been shown for the purpose of illustrating the present invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the present invention. Therefore, it should be understood that changes may be made in the specific embodiments described, and these changes will be within the full intended scope of the present invention as defined by the appended claims.

Claims

1. A non-pneumatic tire and wheel assembly comprising: A wheel having a first bead ring retainer and a second bead ring retainer, a non-pneumatic tire having a shear band and a tread forming a tread band, and a first sidewall region and a second sidewall region; wherein said first sidewall region and said second sidewall region each extend from said tread band and terminate in respective first and second bead regions, wherein a carcass ply extends beneath a crown portion of the non-pneumatic tire and into the first and second sidewall regions and has a first end secured to a first bead region and a second end secured to a second bead region, wherein the first bead region and the second bead region are each mounted on the first bead retainer and the second bead retainer; and wherein the carcass ply is tensioned when each bead area is mounted on a corresponding bead retainer of the wheel; Wherein when mounted on the rim of the wheel, each bead is tensioned axially outwardly but axially inwardly of a corresponding shoulder of the non-pneumatic tire.

2. The non-pneumatic tire and wheel assembly of claim 1, wherein the first and second sidewall regions each have an upper sidewall region that is not connected to the outer lateral ends of the tread band.

3. The non-pneumatic tire and wheel assembly of claim 2, wherein when the non-pneumatic tire is not mounted on the wheel and is in an unloaded condition, in an uncoupled position, the carcass ply has a first radius R1 below the crown region of the tread and a second radius R2 in the upper sidewall region, and wherein R1 is greater than R2.

4. The non-pneumatic tire and wheel assembly of claim 1 wherein the shear band is loaded in compression when the non-pneumatic tire is mounted on the wheel.

5. The non-pneumatic tire and wheel assembly of claim 1 wherein the shear band is circumferentially compressed when the non-pneumatic tire is mounted on the wheel.

6. The non-pneumatic tire and wheel assembly of claim 1, wherein an axial distance between the first bead ring and the second bead ring is axially adjustable.

7. The non-pneumatic tire and wheel assembly of claim 1 wherein each sidewall region has at least two reinforcing plies.

8. The non-pneumatic tire and wheel assembly of claim 1 wherein the first end and the second end of the carcass ply are located in the crown portion of the tire.

9. The non-pneumatic tire and wheel assembly of claim 1, wherein the first and second sidewall regions are angled at an angle α relative to a horizontal surface of the rim.

10. The non-pneumatic tire and wheel assembly of claim 1, wherein each bead region further comprises an apex (430, 2300).

11. The non-pneumatic tire and wheel assembly of claim 10, wherein the apex is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289.

12. The non-pneumatic tire and wheel assembly of claim 10 or 11, wherein each bead region further comprises a second apex core (2400), wherein the second apex core is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289.

13. The non-pneumatic tire and wheel assembly of claim 10, wherein the lower sidewall portion of each sidewall region has a rib reinforcement located axially outward of the apex core, and wherein the rib reinforcement is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100°C according to ASTM D5289.

14. The non-pneumatic tire and wheel assembly of claim 1 , wherein the lower sidewall portion of each sidewall region has a chafer, and wherein the chafer is formed of a hard material having a shear storage modulus G' ranging from 14 to 43 MPa measured at 1% strain and 100° C. according to ASTM D5289.

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