The present application relates to tires and, more particularly, to a tire with a sidewall reinforcement to improve sidewall performance of the tire and a body ply and insert assembly method.
In an inflated and loaded condition, a radial tire is subject to bending moments at the sidewall areas at the center of the tire footprint. The strains and stresses created by the moments are directly related to the sidewall performance of the tire.
Previous research and studies have demonstrated that the maximum sidewall surface strain occurs in the least stiff area of the sidewall of a tire. Because of cord compression created during the loading of the tire, the combined cord tension in the upper sidewall area is reduced and that area is most vulnerable to sidewall bending. Therefore, the maximum sidewall surface strain is located in the upper sidewall area.
A tire, which has a maximum section width, an upper section above the maximum section width, and a lower section below the maximum section width, includes a tread extending circumferentially about the tire, a pair of sidewalls, a pair of bead assemblies, and at least one carcass ply extending circumferentially about the tire from one bead assembly to the other. The tire further includes first and second reinforcement plies extending circumferentially about the tire, disposed between the at least one carcass ply and the tread and at least one of the sidewalls of the tire. The first and second reinforcement plies have lower ends that terminate in the lower section of the tire.
Further, a method for making a tire body ply is also described. The method includes delivering a first rubber coating to a bite formed by at least two calendering rollers, delivering at least one insert to the bite, delivering a body fabric to the bite, and delivering a second rubber coating to the bite. The method further includes pressing the first rubber coating, the body fabric, the at least one insert, and the second rubber coating through the bite and then between the at least two calendering rollers to form a tire body ply having a total width, a thickness, and a length. In one embodiment, the method also includes placing the body fabric and the at least one insert between the first rubber coating and the second rubber coating and placing the at least one insert between the first rubber coating and the body fabric. In another embodiment, the method includes placing a first insert having a first width so it is spaced from a center of the tire body ply by a first distance and placing a second insert having a second width so it is spaced from the center of the tire body ply by a second distance.
In the accompanying drawings, embodiments of a body ply and insert assembly method are illustrated that, together with the detailed description provided below, describe exemplary embodiments of body ply and insert assembly methods. One of ordinary skill in the art will appreciate that a step may be designed as multiple steps or that multiple steps may be designed as a single step.
Further, in the accompanying drawings and description that follow, like parts are indicated throughout the drawings and written description with the same reference numerals, respectively. The figures are not drawn to scale and the proportions of certain parts have been exaggerated for convenience of illustration.
The following includes definitions of selected terms employed herein. The definitions include various examples and/or forms of components that fall within the scope of a term and that may be used for implementation. The examples are not intended to be limiting. Both singular and plural forms of terms may be within the definitions.
“Axial” or “axially” refer to a direction that is parallel to the axis of rotation of a tire.
“Bite” or “calender bite” refer to a location between two rollers where materials merge, wherein the two calender rollers press the materials together.
“Circumferential” and “circumferentially” refer to lines or directions extending along the perimeter of the surface of the tread parallel to the equatorial plane and perpendicular to the axial direction of the tire.
“Equatorial plane” refers to the plane that is perpendicular to the tire's axis of rotation and passes through the center of the tire's tread.
“Groove” refers to an elongated void area in the tread of the tire that extends circumferentially in a straight, curved or zig-zag manner.
“Lateral” or “laterally” refer to a direction along the tread of the tire going from one sidewall of the tire to the other sidewall.
“Radial” or “radially” refer to a direction perpendicular to the axis of rotation of the tire.
“Sidewall” refers to that portion of the tire between the tread and the bead.
“Tread” refers to that portion of the tire that comes into contact with the road under normal load.
Directions are also stated in this application with reference to the axis of rotation of the tire. The terms “upward” and “upwardly” refer to a general direction towards the tread of the tire, whereas “downward” and “downwardly” refer to the general direction towards the axis of rotation of the tire. Thus, when relative directional terms such as “upper” and “lower” are used in connection with an element, the “upper” element is spaced closer to the tread than the “lower” element. Additionally, when relative directional terms such as “above” or “below” are used in connection with an element, an element that is “above” another element is closer to the tread than the other element. The terms “inward” and “inwardly” refer to a general direction towards the equatorial plane of the tire, whereas “outward” and “outwardly” refer to a general direction away from the equatorial plane of the tire and towards the sidewall of the tire. Thus, when relative directional terms such as “inner” and “outer” are used in connection with an element, the “inner” element is spaced closer to the equatorial plane of the tire than the “outer” element.
Illustrated in
With continued reference to
A carcass ply 114 extends circumferentially about the tire 100 from one bead assembly (e.g., bead assembly 106) to the other bead assembly (not shown). The carcass ply 114 is wound outwardly about the bead core 108 and extends upwardly towards the tread 102 to form a turn-up portion 118. The turn-up portion 118 terminates at a turn-up end 122. Although the tire 100 illustrated in
With continued reference to the embodiment illustrated in
In one embodiment, the carcass ply 114 includes parallel-aligned cords that are radially disposed. In other words, the parallel-aligned cords are oriented substantially perpendicular to the equatorial plane Ep of the tire 100. In alternative embodiments, the carcass ply can include parallel-aligned cords that are biased with respect to the equatorial plane Ep of the tire 100. In all cases, the cords can be constructed of, for example, nylon or polyester.
With continued reference to
In one embodiment, the first and second belts 126, 128 include parallel-aligned cords or wires that are radially disposed. In alternative embodiments, one or more of the belts can include parallel-aligned cords or wires that are biased with respect to the equatorial plane Ep of the tire 100. In all cases, the cords or wires can be constructed of, for example, steel or other steel alloys.
With continued reference to
The tire 100 further includes a tread cap 142 provided between the tread 102 and the first and second belts 126, 128. The tread cap 142 can be used to assist in holding the components of the tire together (e.g., the belts, plies, and tread). The tread cap 142 can include, for example, one or more polyester or nylon fabric plies. Although shown in the
As shown in
Illustrated in
As shown in the embodiment illustrated in
With continued reference to
The lower ends 208, 212 of the first and second reinforcement plies 202, 204 terminate in the lower section L of the tire 100. More specifically, the lower ends 208, 212 of the first and second reinforcement plies 202, 204 may extend beyond the upper end 216 of the bead filler insert 214. In other words, the bead filler insert 214 may overlap the first and second reinforcement plies 202, 204. Preferably, the lower end 208 of the first reinforcement ply 202 extends beyond the upper end 216 of the bead filler insert 214 by a radial distance R1 between about 4 mm and about 6 mm. Similarly, the lower end 212 of the second reinforcement ply 204 extends beyond the upper end 216 of the bead filler insert 214 by a radial distance R2 between about 10 mm and about 15 mm.
The termination of the lower ends 208, 212 of the first and second reinforcement plies 202, 204 can also be discussed in relation to the turn-up end 124 of the carcass ply 114. For example, the lower ends 208, 212 of the first and second reinforcement plies 202, 204 extend downwardly beyond the turn-up end 124 of the carcass ply 114. In other words, the turn-up portion 118 of the carcass ply 114 overlaps the first and second reinforcement plies 202, 204. Preferably, the lower end 212 of the second reinforcement ply 204 extends beyond the turn-up end 124 of the carcass ply 114 by a radial distance R3 (which is approximately the same distance as R2 as shown in
Although
Illustrated in
As shown in
With reference to
The first reinforcement ply 202 preferably has a thickness T1 between about 0.6 mm and about 1.2 mm and the second reinforcement ply 204 preferably has a thickness T2 between about 0.6 mm and about 1.2 mm. Most preferably, the first reinforcement ply 202 has a thickness of about 1.0 mm and the second reinforcement ply 204 has a thickness of about 1.0 mm. Hence, the preferred total thickness T3 of the dual layer reinforcement is about 2.0 mm.
In one embodiment, the first and second sets of parallel-aligned cords 302, 304 are constructed of nylon. In alternative embodiments, one or both sets of parallel-aligned cords 302, 304 may be constructed of polyester, rayon, or steel.
By providing the dual layer reinforcement in one or both sidewalls of a tire, sidewall performance of the tire is improved. For example, when the tire deflects, the dual layer reinforcement is shifted outward towards the sidewall of the tire, thereby increasing the stiffness of the sidewall of the tire. As stiffness of the sidewall of the tire increases, surface strain in the sidewall of the tire decreases. Reduction of surface strain at the sidewall of the tire can lead to a reduction of surface cracks at the sidewall of the tire, a reduction of deflection of the sidewall, and/or an improvement in vehicle handling.
The following example demonstrates the potential effects of providing the dual layer reinforcement in both sidewalls of a tire and should not be construed as limiting the scope or spirit of the present application.
A P255/45R/18 tire, having a maximum allowable inflation of 35 psi and maximum load capacity of 1709 lb (hereinafter referred to as the “Control Tire”), was inflated to 19 psi (its minimum allowable inflation) and mounted on a fixture. A computer system, which employs several cameras focused on the Control Tire, was used to obtain dimensional data of the Control Tire in its unloaded state.
A maximum load of 1709 psi was then applied to the Control Tire causing it to deflect. The computer system then obtained dimensional data of the Control Tire in its loaded state. The dimensional data of the Control Tire in its unloaded state was then compared to the dimensional data of the Control Tire in its loaded state to determine actual strain values along various points on the sidewall of the Control Tire.
This dimensional data was also used to create a computer simulated model of the Control Tire. Modifications could be made to the computer simulated model of the Control Tire to create virtual tires. From these virtual tires, surface strain values along any point on the sidewall of a tire could be predicted. In this case, the computer simulated model of the Control Tire was modified to create a virtual tire that included a half-ply, dual layer reinforcement (nylon cords; 45° equal, but opposite bias) similar to the one described above and shown in
In the illustrated embodiment, first rubber coating 525, second rubber coating 540, and at least one insert 530 include vulcanized rubber materials. Body fabric 535 comprises woven fabric, e.g., natural and synthetic fabrics. In an alternative embodiment (not shown), first rubber coating 525, second rubber coating 540, and at least one insert 530 are comprised of at least one of the following materials: unvulcanized rubber, polyester calendered with rubber skim on both sides, and the like. In another alternative embodiment (not shown), first rubber coating 525, second rubber coating 540, and at least one insert 530 are constructed of a combination of at least two of the following materials: unvulcanized rubber, polyester calendered with rubber skim on both sides, and the like.
In the illustrated embodiment, rollers deliver first rubber coating 525, at least one insert 530, body fabric 535, and second rubber coating 540 to a calender bite 555 formed by a first calendering roller 545 and a second calendering roller 550. Calender bite 555 presses together (i.e., calenders) first rubber coating 525, at least one insert 530, body fabric 535, and second rubber coating 540 to form a tire body ply and insert assembly 560 that is collected by at least one take up roller 565.
After body ply assembly 560 has been formed, two bead portions are placed on its top surface.
In the illustrated embodiment, the bead portion right of the center line CL includes bead core 575b having a center C2 and a bead filler 580b. Center C2 of second bead core 575b is axially spaced from second axial edge 570b by a sixth distance D6 and axial outer edge OAE2 of second insert 530b is axially spaced from second axial edge 570a by fourth distance D4, wherein fourth distance D4 is greater than sixth distance D6. In another embodiment (not shown), fourth distance D4 is about equal to sixth distance D6. In yet another embodiment (not shown), fourth distance D4 can be from about 1.1 times the sixth distance D6 to about 3.5 times the sixth distance D6. In an example embodiment, fourth distance D4 is about 20 millimeters to about 50 millimeters greater than sixth distance D6.
After the bead portions have been placed on the top surface of the body ply assembly 560, the first axial edge 570a and second axial edge 570b are turned up and folded over the respective bead portions.
To the extent that the term “includes” or “including” is used in the specification or the claims, it is intended to be inclusive in a manner similar to the term “comprising” as that term is interpreted when employed as a transitional word in a claim. Furthermore, to the extent that the term “or” is employed (e.g., A or B) it is intended to mean “A or B or both.” When the applicants intend to indicate “only A or B but not both” then the term “only A or B but not both” will be employed. Thus, use of the term “or” herein is the inclusive, and not the exclusive use. See, Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). Also, to the extent that the terms “in” or “into” are used in the specification or the claims, it is intended to additionally mean “on” or “onto.” Furthermore, to the extent the term “connect” is used in the specification or claims, it is intended to mean not only “directly connected to,” but also “indirectly connected to” such as connected through another component or multiple components.
While the present application illustrates various embodiments, and while these embodiments have been described in some detail, it is not the intention of the applicant to restrict or in any way limit the scope of the claimed invention to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention, in its broader aspects, is not limited to the specific details, the representative apparatus, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's claimed invention.
This U.S. non-provisional application is a continuation-in-part application that claims priority from U.S. Non-provisional patent application Ser. No. 11/219,160, inventors Jin et al., entitled TIRE HAVING A SIDEWALL REINFORCEMENT, filed Sep. 1, 2005, the disclosure of which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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Parent | 11219160 | Sep 2005 | US |
Child | 12577235 | US |