MXPA98001237A - Pneumatic rim that has a single reinforced cover coat with metallic strings, a construction of extreme heavy coat, folded up and before enclav - Google Patents

Abstract

The present invention relates to a pneumatic tire characterized by: (a) a pair of axially spaced annular eyebrow cores, each eyebrow core comprises a plurality of single-row metallic turns, each eyebrow core with a radial transverse shape; (b) a single layer of roof reinforced with parallel metallic ropes composed of at least one filament having a tensile strength of at least (-2000 x D + 4400 Mpa) x 95%, where D is the diameter of the filament in millimeters, the only covering layer is bent around each eyebrow core, the cover layer having a main portion extending between the eyebrow cores and the upturned portions that bend around the cores, eyebrow , a radially outer edge of each portion bent upwards is in contact with the main portion and extending to an extreme point 0.5 inches (12.7 mm) to 4.0 inches (101.6 mm) ) radially outwardly of the eyebrow core, as measured along the main portion of the tire cover layer, c) a bead reinforcement associated with each eyebrow core has a first and second ends where it is positioned directly adjacent to the cover layer, the first end being located on the axially inner side of the main portion of the cover layer at a location around 0.4 inches (10 mm) to 3.5 inches (89 mm) radially outward from the eyebrow core as measured along the main portion of the cover layer and the second end being located at a point in the range from substantially the axially outermost point of the eyebrow core to approximately 3.5 inches ( 89 mm) radially outwardly from the eyebrow core as measured along the upwardly bending portion of the cover layer, and wherein the first end and the second end Bead reinforcement is a shorter radial distance from the core of the eyebrow than the end point of the radial portion bent upward of the cover layer

Description

PNEUMATIC RIM THAT HAS ONLY ONE COVER LAYER REINFORCED WITH METALLIC STRINGS, A LAYER CONSTRUCTION EXTREME ELEVATED, FOLDED UP AND EYE LOCKED BACKGROUND OF THE INVENTION The present invention relates to a pneumatic rim having a single reinforced cover, with high strength metal cords and a construction with raised termination bend and interlocking eyebrow.

Field of the art The intention of having portions bent upwardly in the layer (or layers) of the tire cover of a pneumatic tire extending radially out of the eyebrow core the shortest possible distance is the premise upon which the prior art developed the eyebrows interlocked. The proposed advantages included better durability of the eyebrow and reduce material costs. US Pat. No. 4,922,985 / filed May 8, 1990, discloses a reinforcing layer or fabric of cover 30 having a main portion extending between both eyebrow cores (not shown) of the rim and portions bent upwardly. which are anchored around each eyebrow core 31. The rims, in accordance with US Pat. No. 4,922,985, have the radially outer edges of the upturned portions of the cover layer arranged radially outwardly from the eyebrow cores. minimum distance and are in contact with the main portion of the cover layer. Suitable elastomeric materials surround the eyebrow core, the cover layer and other elastomer components complete the rim flange portion. In Figure 4 of this patent there is illustrated a fastening member 432 consisting of a side-by-side strip of a heat-shrinkable material immersed in a suitable elastomeric substance having a permanent thermal shrinkage of at least 2o. This strip of strings extends from a location radially and axially inward of the center of the eyebrow 431 to a radially outward location of the eyebrow core and without a filler strip or apex placed between the main portion and the upturned portion of the eyebrow. cover layer. The rims, according to US Pat. No. 4,922,985, were manufactured using a fastening member in which the heat shrinkable material was 1260/2 nylon 6, 6, with a permanent thermal shrinkage close to 4 °. A constant goal in the art is to simplify construction and reduce tire manufacturing costs, and still improve the durability, handling, rolling resistance and other properties of the tires.

SUMMARY OF THE INVENTION The present invention relates to a pneumatic tire having a pair of axially spaced annular eyebrow cores and a single cover layer that is bent around each eyebrow core. Each eyebrow core consists of a plurality of turns of a single metallic filament. The single cover layer is reinforced with parallel metallic ropes composed of at least one filament having a tensile strength of at least (-2000 x D + 4400 MPa) x 95o, where D is the diameter of the filament in millimeters The single cover layer is folded around each eyebrow core. The single cover layer has a main portion extending between the eyebrow cores and the upturned portions that are bent around the eyebrow cores. A radially outer web of each upwardly bent portion contacts the main portion of the cover layer and extends to an end point 0.5 inches (12.7 mm) to 4.0 inches (101.6 mm) radially outward from the eyebrow core, measured along the main portion of the tire cover layer. No eyebrow apex or padding is present between the fold up of the cover and the main portion of the cover layer. An associated heel reinforcement with each eyebrow has each end (first and second) of the heel reinforcement disposed directly adjacent to the cover layer. One end (the first) is located on the axially inner side of the main portion of the cover layer at a location approximately 0.4 to 3.5 inches (10 mm to 89 mm) radially outward from the eyebrow core when measured at length of the main portion of the cover layer. The other or second end of the bead reinforcement is located at a point in the range from substantially the axially outermost point of the eyebrow core to about 3.5 inches (89 mm) radially outward from the eyebrow core., as measured along the portion that is bent upwards of the cover layer. The first end and the second end of the bead reinforcement are at a shorter radial distance from the eyebrow core than the end point of the radial portion bent upward of the cover layer. The respective upwardly bent portion of the cover layer is directly adjacent to the bead reinforcement and the eyebrow core.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial or fragmentary cross-sectional view of a rim according to the present invention; Figure 2 is a fragmentary sectional view of a portion of the rim flange, in accordance with the present invention, installed in a rim.

DETAILED DESCRIPTION OF THE INVENTION When used herein and in the claims: "Axial" and "axially" is used herein to indicate lines or directions parallel to the axis of rotation of the rim. "Eyebrow" means the part of the rim comprising an annular member subjected to traction wrapped by the strings of the layer and formed, with or without other reinforcement elements, such as fins, chips, vertices, bead reinforcements, abrasions, for fit the rim design of the rim. "Belt structures" means at least two layers of reinforcing fabric of parallel strings woven or non-woven, below the running surface, not anchored to the eyebrow and having the angles of the left and right cord in the range from about 17 to about 27 ° with respect to the equatorial plane (PE) of the rim. "Cover" means the structure of the rim independent of the belt structure, the running surface and the lower part of the running surface, but includes the eyebrows. The cover layer includes reinforcing cords embedded in a thermal elastous substance; and these components are considered a single entity. The "main part of the cover layer" means the part of the cover layer that extends between the two eyebrow cores. "Rope" means one or more of the reinforcing elements, formed by one or more filaments / wires that may or may not be twisted, or otherwise formed, and which may also include yarns, which may or may not be formed as well. "Crown" means that portion of the rim within the amplitude limits of the tread surface of the rim. "Equatorial plane (PE)" means the plane perpendicular to the axis of rotation of the rim and passing through the center of the tread surface of the rim.

"Load range" means the limits of the load and the capacity to receive air or inflation for a given tire, used in a specific type of service, as defined in the tables of The Tire and Rim Association, Ine, 1995, Year Book. "Layer" or reinforcement fabric means a continuous layer of parallel filaments coated with rubber.

"Pneumatic tire" means a mechanical laminated device, generally toroidal in shape (usually an open toroid) having eyebrows, a cover layer and a running surface. "The prefix letters" means those identifications that are used and defined in The Tire and Rim Association, Ine, 1995, Year Book. "Radial" and "radially" is used to indicate sections radially perpendicular to the axis of rotation through the rim. "Radial layer rim" means a pneumatic rim or circumferentially limited rim, in which the reinforcing fabrics of the cover layer extending from eyebrow to eyebrow are at angles between 75 ° and 105 ° with respect to the plane equatorial of the tire. "Rivet" means the open space between ropes in a layer. "Section width" means the maximum linear distance parallel to the axis of the rim and between the outside of its sidewalls when and after it has been inflated to normal pressure for 24 hours, but without load, excluding the elevations of the walls laterals due to labeling, decoration or protective bands. "Tensile strength" is determined by ASTM A370-92 applied to a steel wire product.

Now, with reference to FIGS. 1 and 2, there is shown a cross-sectional view, in fragment, of a rim 10 according to the present invention and a fragmented, amplified view of an eyebrow portion and a lower side wall installed in a rim. . Figure 1 shows a fragmentary cross-sectional view of a rim 10 of the present invention. The rim has a pair of eyebrow cores 11 (only 1 is shown) which, each contains a plurality of metallic filaments. The rim 10 is characterized by a single layer of reinforcement fabric 12 of the cover, which extends between the eyebrow cores 11 and an upwardly bent portion anchored around each eyebrow core 11. A belt structure having at least 2 belts 13, 14 that are positioned radially outwardly of the main part of the cover layer, and a portion of the running surface touching the floor 15 is disposed radially outwardly of the belt structure. The portions of the side wall 16 (shown one) extend radially inwardly from the portion of the running surface toward the eyebrow portions. On the axially inner side of the cover layer, an inner liner 17 can be used. The inner lining consists of a layer or layers of elastomer or other material that forms the inner surface of the rim and contains the fluid to inflate it, as be the air, inside the rim 10. It may be desirable to place additional barriers, reinforcement strips or rubber strips (not shown) at suitable locations between the inner liner 17 and the main portion of the cover layer to prevent penetration of rubber through the cover layer during vulcanization. A crucial aspect of the invention is the construction of the single layer layer reinforced with parallel metallic cords composed of filaments as described above. There are several metallurgical modalities that result in the tensile strength defined in the above. One way to achieve this resistance is by mixing the appropriate process and alloys as described in U.S. Patent Nos. 4,960,473 and 5,066,455, which are incorporated herein by reference in their entirety, with a micro-alloyed steel rod with one or more of the following elements: ni, fe, cr, nb, si, mo, mn, cu, co, vyb. The preferred chemical elements are listed below in percentages by weight: C 0.88 to 1.0 Mn 0.30 to 0.05 Si 0.10 to 0.3 Cr 0 to 0.4 V 0 to 0.1 CU 0 to 0. 5 Ni 0 to 0 .5 CO 0 to 0. 1 being the difference iron and waste. The resulting rod is then stretched for adequate tensile strength. For equal diameters of the filament, the cords used in the present invention have superior strength and usually superior fatigue life over the prior art tensioned cords. These advantages give rise to pneumatic tires that have less reinforcement material and thus less weight and cost. In addition, the life of the tire can be increased with the increase in the fatigue life of the rope and its filaments. When the new rope structures incorporate filaments with smaller diameters there is a consequent reduction in the calibrated material and cost, compared to high or higher tensile strengths, making the tires lighter in weight and less expensive. The ropes for use in the single layer cover layer may consist of one (monofilament) to multiple filaments. The amount of total filaments in the string can be in the range from 1 to 13. Preferably, the number of filaments per string is in the range from 6 to 7. The individual diameter (D) of each filament is, in general, in the range from 0.15 to 0.30 mm for each filament having at least a tensile strength of (-2000 x D + 4400) x 95 '¿, where D is the diameter of the filament in mm. Preferably, the diameter of each filament is in the range from 0.17 to 0.22 mm. Another important property of the steel rope is that the total elongation for each filament in the rope must be at least 2% over a calibrated length of 25 cm. The total elongation is measured in accordance with ASTM A370 / 92. Preferably, the total elongation of the rope is in the range from about 2% to 4 '?. A particularly preferred total elongation is in the range from about 2.2 to about 3.0. The torsion values for the steel in the filament used in the rope must be at least 20 turns with a calibrated length of 200 times the diameter of the wire. In general, the value of the torsion is in the range of about 20 to about 100 turns. Preferably, the torsion values are in the range from about 30 to about 80 turns, with a range from about 75 to about 65 being particularly preferred. The torsion values are determined according to the test method ASTM E558-83 with test lengths of 200 times the diameter of the wire.

There are several constructions of specific metal ropes for use in the single cover layer. Representative examples of specific string constructions include 1 x, 2 x, 3 x, 4 x, 5 x, 6 x, 7 x, 8 x, 11 x, 12 x, 1 + 2, 1 + 4, 1 + 5, 1 + 6, 1 + 7, 1 + 8, 2 + 1, 3 + 1, 5 + 1, 6 + 1, 11 + 1, 12 + 1, 2 + 7, 2 + 7 + 1, 3 + 9, l + 5 + lyl + 6 + lo 3 + 9 + l, the outer wrapping filament can have a tensile strength of 2500 MPa or greater based on the filament diameter of 0.15 mm. The most preferred rope constructions including filament diameters are 3 x .18, 1 + 5 x .18, 1 + 6 x .18, 2 + 7 x .18, 2 + 7 x .18 x 1 x .15, 3 + 9 x .18 + 1 x .15, 3 + 9 x .18, 3 x .20 + 9 x .18 and 3 x .20 + 9 x .18 + 1 x 15. The previous string designations are understandable for those skilled in the art, for example, the designation 2 x, 3 x, and 4 x means a bundle of filaments; that is 2 filaments, 3 filaments, 4 filaments and the like. The denomination as 1 + 2 and 1 + 4 indicates, for example, a single filament wrapped by two or four filaments. The cover layer 12 has a layer of steel cords, as described above, arranged so as to have from about 5 to about 70 ends per inch (* 2 to 28 ends per cm) when measured at the The equatorial plane of the rim, preferably, the string layer is arranged so that it has about 7 to about 20 ends per inch (* 2.7 to 8 extremes per cm) in the equatorial plane. The above calculations for the ends per inch are based on the range of diameters for the rope, the strength in the rope and the practical resistance requirement for the cover layer. For example, the upper end-per-inch number included the use of lower diameter ropes for a given strength compared to a lower number of ends per inch for a larger diameter wire, for the same strength. In the alternative, if one selects the use of a rope of a given diameter, one may have to use more or fewer ends per inch depending on the strength of the rope. The metal cords of the cover layer 12 are oriented so that the rim, according to the present invention, is what is commonly known as radial. The steel cord of the roof layer intersects the equatorial plane (PE) of the rim at an angle in the range from 75 ° to 105 °, preferably the steel cords intersect at an angle of 82 °. at 98 ° The preferred range is from 89 ° to 91 ° A rim, according to the present invention, has a pair of axially spaced eyebrow cores 11, which each comprise a plurality of single filament turns Each of the eyebrow cores has a radial transverse shape which can be substantially pentagonal, hexagonal, rectangular or circular.In the case where the eyebrow has a radial transverse shape that is substantially pentagonal, the amplitude of the largest axis of the eyebrow The eyebrow core is located radially outward from the radially innermost edge of the eyebrow core.When used herein, a "radial cross section" is a cross section taken in the plane containing the eyebrow. the axis of rotation of a tire or the tire and rim unit. When used herein, "substantially pentagonal" means a cross section of five sides, although some or all sides may be curvilinear rather than rectilinear, as in a regular pentagon. The radially outermost extension of the eyebrow core being a vertex of two of the sides of the pentagon and the largest axial amplitude of the eyebrow core located radially outward from the outermost edge of the eyebrow core. A cover layer 12 and a heel reinforcement 18 are folded around each eyebrow core 11. As already mentioned, the cover layer 12 has a main portion extending between the eyebrow cores and the portions that are bent towards above, which are bent around the eyebrow cores 11. The radially outer edge of each portion is bent upwardly contacts the main portion of the cover layer and extends to an end point 12a, 0.5 inches (12.7 mm) 4.0 inches (101.6 mm) radially outwardly of the core of the eyebrow 11, as measured along the main portion of the tire cover layer. Preferably, the upturned portion extends toward an end point 12a, 0.5 inch (12.7 mm) to 3.5 inch (88.9 mm) radially outward from the eyebrow core 11. Immobilization at the eyebrow is achieved by the adhesion between the upper portion that bends upward and the main portion of the single layer of cover, and the restriction of the flange of the wheel 22 when the tire is installed in the wheel and inflated. As can be seen in figure 2, the entire construction of the eyebrow is below the top of the flange and the pentagonal shape of the eyebrow corresponds to the natural pressures between the rim and the rim while keeping the eyebrows in the rim when inflates the tire This is particularly true when tires employing higher inflation, e.g., 50 psi, use the construction of the present invention. Also, because the axially outer end of the bead reinforcement 18 is held below the top of the rim flange 22a, the opportunities for the heel reinforcement to undergo separation at the end of the layer are substantially reduced. The upward, upper fold and the consequent high contact area with the adhesive between the fold up and the main cover layer also stabilizes the eyebrow. A bead reinforcement 18 is associated with each eyebrow core 11. Each bead roll 18 has a first end 18a and a second end 18b. Each end 18a and 18b is positioned directly adjacent to the cover layer 12. The first end 18a is located on the axially inner side of the main portion of the cover layer at a location around 0.4 inches (10 mm) to 3.5 inches (89 mm) radially outward from the eyebrow core. Preferably, the first end 18a is located on the axially inner side of the main portion of the cover layer at a location about 0.4 inches (10.16 mm) to 2.0 inches (10.8 mm) radially outward from the eyebrow core . The second end 18b of the bead reinforcement 18 is located at a point in the range from substantially the axially outermost point of the eyebrow core to a location about 3.5 inches (89 mm) radially outwardly from the eyebrow core, as measured along the upwardly bending portion of the cover layer. Preferably, the second end 18b of the bead reinforcement 18 is located at a point in the range from substantially the axially outermost point of the eyebrow core to a location about 2.0 inches (50.8mm) radially outward from the core of the eyebrow core. eyebrow. The heel reinforcement 18 may be a rubber material, a flexible textile material or a heat shrinkable material. For example, according to one embodiment, the heel reinforcement 18 may consist of a side-by-side stringer strip of a non-metallic heat-shrinkable material having a thermal shrinkage of at least 2%. Shrinkage, in general, works from about 2% to 5%. The strings, usually, oriented from 0 ° to 75 ° with respect to the central plane of the rim. The strip of strings from side to side is usually wrapped in the circumferential direction around the eyebrow core and the part that is bent upwards of the cover layer, a plurality of times. When used herein the term "permanent thermal shrinkage" means the intrinsic dimensional stability of a material when subjected to an elevated temperature indicated by the percentage of permanent shrinkage, which is determined using the test method and the apparatus that is used. described in US Pat. No. 4,922,985, which is incorporated by reference in its entirety. Representative examples of side-by-side cords of a non-metallic heat-shrinkable material having a thermal shrinkage of at least 2o include the use of 1260/2 nylon 6, 6 cords, 850/1 nylon 6,6 cords. , strings 1000/1 nylon 6.6. The strings may be parallel to each other or square fabric. Examples of a rubber material include rubber strips. The single cover layer 12 and the heel reinforcement 18 are introduced into suitable elastomeric compounds. In addition to the elastomeric compound containing the core of the eyebrow and the cover layer, no apex per fill strip is usually present or needed between the upward portion of the cover layer and the main portion. of the cover layer. However, a tire core designer can use an apex or filler strip if desired. A belt structure comprising a plurality of belt layers 13, 14 is located radially outwardly of the single cover layer 12 in a crown portion of the rim. A portion of the rolling surface, the thermal elasto, 15 is disposed radially outwardly of the belt structure. The structure of the belt has at least two annular layers or reinforcing fabrics of parallel strings, woven or non-woven, below the running surface, not anchored to the eyebrow. In general, the belt structure has the angles of the rope, the left and right angles from 40 to 15 ° with respect to the equatorial plane of the rim. It is understood that the particular belt structure illustrated in FIGS. 1 and 2, and which is described herein, is simply an example that is used in the preferred embodiment and that a tire designer can employ any arrangement of layers of tires. belt according to the operating requirements of the specific rim, while still practicing the present invention. For example, in those cases where a larger radial tire is built for use in a light truck application, it is possible to use 3 or more belts. In addition, the cords in the belt layers may be made of polyester rayon, fiberglass, aramid, steel wire or the like. Preferably, the rope is made of steel wire with a tensile strength of at least (-1400 x D + 4050) x 95 < s when D is as already described. Particularly preferred are strings composed of at least one filament having a tensile strength of at least (-2000 TL D + 405O) x 95 'when D is as described above. The pneumatic tires of the present invention can be designed for various load ranges. For example, the load ranges can be A, B, C, D or E. Preferably, the load range is E.

The pneumatic tires of the present invention can also be designed for different prefix letters depending on the designated service conditions that require different loads and inflation capabilities. For example, tires can be designated by AT, LT, P and ST. Preferably, the pneumatic tire is LT. A radial tire pneumatic tire, according to figures 1 and 2, was manufactured in size LT 235/85 R16. The metallic filament that was used in the eyebrow cores of the illustrated modality is 0.05 inch (1.27 mm) diameter steel wire coated with bronze to improve its bond with the rubber. Of course, depending on the size of the rim other filament diameters may be used in the practice of the invention. Each of the eyebrow cores 11 has a radial transverse shape that is substantially pentagonal. For example, in the LT235 / 85R16 light truck rim, each of the eyebrow cores can be manufactured with 8 radially overlapping layers of single metallic filament turns. The nr of turns in each layer, starting with the radially innermost layer being 4, 5, 6, 5, 4, 3, 2, 1. For other tire sizes you can use different nr of layers and nr of turns in each cap. The single cover layer and the heel reinforcement are introduced into a suitable elastomeric compound. It may be desirable to interpose a fin between the cover layer and the pentagonal eyebrow core. The flap can be of the same material that is used in the heel reinforcement or a layer of a rigid abrasion resistant rubber. The flap is proposed to prevent chafing of the cords of the cover layer against any sharp edge of the eyebrow core. An alternative to using a fin is to wrap the eyebrow with materials that show utility as fins. A rim, according to the modality illustrated in the figures I and 2, has a heel reinforcement consisting of ropes 850/1 nylon 6, 6 placed in 28 ropes per inch (« II cords x cm) and oriented at 45 ° with respect to a plane parallel to the equatorial plane PE of the rim. The upward fold of the cover layer is folded around a pentagonal eyebrow beam 11 and is blocked against the main portion of the cover layer 12 by the side wall 16. In the illustrated embodiment, the single cover layer with Ja-portion bent up ends at an end point 12a, 2.8 inches (* 71 mm), respectively, radially outwardly of the eyebrow core, when measured along the main portion of the cover layer. In the specific illustrated embodiment (see Figure 1) the axially outer end 18b of the bead reinforcement 18 is located at a point substantially coinciding with the axially outermost point of the eyebrow core. The axially inner end 18a of the bead reinforcement 18 is located 0.56 inches (13 mm) radially outwardly of the eyebrow core, when measured along the main portion of the cover layer. A reinforcing, elastomeric, axially outer member 20 consisting of an elastomeric composite having a Young Module of 3400 pounds per square inch (psi), or greater, is located from a point axially outward of the cover layer and the heel reinforcement and extends to a point located along the short, upward bending portion of the end 12. For example, on a tire of size LT235 / 85R16 having a maximum section height A of near of 7.8 inches (19.81 cm), the axially outer reinforcing member extends radially outwardly a distance B of about 2.5 inches (6.35 cm) from the core of the rim flange. When used herein the term "Young's Modulus" is the tensile property that is determined in accordance with the test procedure described in U.S. Patent 5,058,649, which is incorporated by reference in its entirety. It has been found that the present eyebrow construction is very stable and can demonstrate high stability by using coating coatings and stiffening compounds having a wide range of properties. Suitable properties for the coating compositions of the layer and compound 20 fall within the following range.

The axially external reinforcing member 20 helps to move the stress concentrations away from the edge of the cover layer 12, which is expected to help reduce the failure due to separations in the components of the rim. A rubber layer of the side wall 16 is axially disposed towards the outside of the cover layer on the side wall portion of the rim in common shape. Using the present construction it has been found that the rim of the invention can be made without using apexes, clamping members or abrasions in the area of the rim flange. This construction is lighter in weight than the constructions of the prior art, which provides operational efficiencies. Production efficiencies are also carried out. It has been found that the construction of the present invention shows better durability of the eyebrow. Although certain representative embodiments and details have been shown for the purpose of illustrating the invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the spirit or scope of the invention.

Example The durability of 4 LT 235 / 85R16 tires (load range E) was tested. Two rims were, according to the present invention and the other two control wheels, had two layers of cover layer reinforced with 1300/3 polyester rope the ends per inches of the control tire for the cover layer were 27 measured on the eyebrow (13.9 on the equatorial plane of the rim). Each rim, according to the present invention, was of a single layer or reinforcing fabric for the roof reinforced with parallel metallic cords (1 + 5 x .18). The EPI in the circumferential plane was 14.3. The tensile strength of filament used in the rope was 4000 MPa, the total elongation for each filament exceeded 2'¿ over a calibrated length of 25 cm, and the torsion values for each filament was between 35 and 65. In addition of these differences, the 4 tires were in accordance with the same specification, including the heel reinforcement. Each heel reinforcement for the 4 rims consisted of 850 / 1- nylon-6,6 strings placed- a, 28 strings per inch ("11 strings per cml and oriented at 45 ° with respect to a plane that is parallel to the PE The second end of each bead reinforcement (axially outward end) was located at a point substantially coinciding with the axially outermost point of the eyebrow core.The first end of each bead reinforcement was located at the axially inner side of the main portion of the cover layer (s) at a location approximately 0.56 inches (13 mm) radially outward from the core of the eyebrow, as measured along the main portion of the (s) ) cover layer (s) The upward fold of the cover layer, for the rim with a single cover layer of the present invention, and the rim with two-layer polyester cover terminated at an end point at 2.8 inches (71 mm) radially towards the exterior of the eyebrow core as measured along the main portion of the cover layer. The following table shows the results of the durability tests. 1 the tires tested on a resilimeter at 80 psi (551.2 KPa) and 100o rated load (load range E) As can be seen from the above data, the rims according to the present invention have improved the durability ranges from 241'¿ to 458 on the two-layer polyester control wheels.

Claims (1)

1. A pneumatic tire characterized by: (a) a pair of axially spaced annular eyebrow cores, each eyebrow core comprising a plurality of single-row metallic turns, each eyebrow core with a radial transverse shape; (b) a single layer of roof reinforced with parallel metal cords composed of at least one filament having a tensile consistency of at least (-2000 x D + 4400 MPa) x 95:?, where D is the diameter of the filament in millimeters. The single cover layer is bent around each eyebrow core, the cover layer having a major portion extending between the eyebrow cores and the upturned portions that bend around the eyebrow cores, an edge- radially outer of each upwardly bent portion is in contact with the main portion and extends to an extreme point 0.5 inches (12.7 mm) up to 4.0 inches (101.6 mm) radially outward from the eyebrow core, as measured at length of the main portion of the tire cover layer; and c) a bead reinforcement associated with each eyebrow core has first and second ends where it is positioned directly adjacent to the cover layer, the first end being located on the axially internal side of the main portion of the cover layer in one place about 0.4 inches (10 mm) to 3.5 inches (89 mm) radially outward from the core of the eyebrow as measured along the main portion of the cover layer and the second end being located at a point in the range from substantially the axially outermost point of the eyebrow core to a location approximately 3.5 inches (89 mm) radially outwardly from the eyebrow core as measured along the portion that is bent upwardly of the eyebrow. cover layer, and wherein the first end and the second end of the bead reinforcement is a shorter radial distance from the core of the eyebrow than the end point of the radial portion bent up above the cover layer. The pneumatic tire of claim 1, characterized in that the single cover layer is reinforced with metal rope constructions selected from the group consisting of 1 x, 2 x, 3 x, 4 x, 5 x, 6 x, 7 x, 8 x, 11 x, 12 x, 1 + 2, 1 + 4, 1 + 5, 1 + 6, 1 + 7, 1 + 8, 2 + 1, 3 + 1, 5 + 1, 6 + 1, 11 + 1, 12 + 1, 2 + 7, 2 + 7 + 1, 3 + 9, l + 5 + lyl + 6 + 1. The pneumatic tire of claim 1, characterized in that D is from 0.15 to 0.30. The pneumatic tire of claim 1, characterized in that the total number of filaments in the metal cord is in the range from 1 to 13. The pneumatic tire of claim 1, characterized in that the metal cords in the cover layer are arranged in a manner that have from 5 to 70 extremes per inch when measured in the equatorial plane of the tire. The pneumatic tire of claim 1, with a load range that is selected from the group consisting of A, B, C, D and E. The pneumatic tire of claim 1, designated by a letter prefix selected from the group consisting of AT, LT, P and ST. SUMMARY OF THE INVENTION The present invention relates to a pneumatic rim having a single shell layer reinforced with parallel metal cords, each cord composed of at least one filament with a tensile strength of at least (-2000 x D + 4400 MPa) x 95'é, where D is the diameter of the filament in millimeters. The upwardly bending portion of the single cover layer 12 in the eyebrow portion of an air tire is interposed between the eyebrow core 11 and a bead reinforcement 18, and the outermost edge of each portion is bent towards above makes contact with the main portion of the cover layer and extends to an extreme point 0.5 inches to 4.0 inches (12.7 mm to 101.6 mm) radially outward from the eyebrow core, measured along the main portion of the tire cover layer. A bead reinforcement 18 associated with each core of the eyebrow 11 has a first and second end and each end is disposed directly adjacent to the cover layer. The first end 18a of the bead reinforcement is located on the axially inner side of the main portion of the cover layer at a location about 0.4 to 3.5 inches (10 to 88.9 mm) radially outward from the eyebrow core, measured at along the main portion of the cover layer, and the second end 18b is located at a point in the range from substantially the axially outermost point of the eyebrow core 11 to a location about 3.5 inches (89 mm) radially towards the outside of the eyebrow core, measured along the portion that is bent upwards of the cover layer. The first end 18a and the second end 18b of the bead reinforcement is a shorter distance from the eyebrow core than the end point 12a of the upwardly bending portion of the cover layer.