MXPA99010856A - Low cost light weight radial tire - Google Patents

Abstract

A very light weight tire (10) has at least one radial ply (38) and a rayon belt structure (36), having two single cut belt layers (50, 51) covered by an overlay (59) having cords (80) selected from the group of aramid, rayon, PEN, PET and PVA. The tire (10) has a very thin or reduced gauge (t) undertead (13). The tire (10) can be made having very low rolling resistance due to the combination of casing structure and the reduced rubber mass.

Description

RADIAL RIM, OF LIGHT WEIGHT AND LOW COST TECHNICAL FIELD This invention relates to pneumatic tires. More specifically, to rims with radial, lightweight tires that have a ratio between dimensions less than 0.8.

BACKGROUND OF THE INVENTION Traditionally, tire engineers have attempted to build very durable tire structures that can survive the severe driving conditions that vehicle operators impose on tires. At first the tires were very heavy and they used multiple layers of skewed strings. The main objective was simply to maintain the air and avoid deflated tires. Through an infinite research process to develop durable and better tire constructions, designs of new and better materials have been developed. The introduction of the radial tire made it practical to develop tires with only one shell layer. The layer was contained radially by a belt structure. To improve the durability of the tire these belt structures evolved to be reinforced mainly by steel. These belts reinforced with steel produced and currently provide a very durable structure. These tires with steel belts have many benefits that make their use attractive. The steel cords are not sensitive to heat, that is, their physical properties are very constant despite the operating temperature of the tire. The steel cords are practically non-extensible and the cords can be made with a very high resistance with fine filaments that have excellent resistance to fatigue. However these belts with steel cords in the tires have given rise to the need to add reference rubber directly on the belts in the area commonly known as the lower part of the tread, in the belt layers themselves and in the areas of the belt edges, all in an attempt to prevent these steel ropes from being exposed or structurally separated at the edges. In many cases the resistance of the steel belt is not necessary and the weight of the alternative organic cords is much lower. The resulting effect has been that radial tires with steel belts are indeed heavier using more rubber in the area of the tread and on the shoulders of the tire. It is precisely in these areas that a large part of the wear to the tread of the tire and the sensitivity to rolling resistance must be the highest. The greater the rubber in this area, the greater the effects of hysteresis and the higher the temperatures under driving conditions. Now a goal of tire designers is to develop tires that generate lower fuel consumption of the car. This can be achieved by designing cold-running tires that have low mass and low rotational inertia and at the same time increasing the operation of the tire and tread management, in addition, the engineer must ensure that the tire tread and the tire Contact patch of the tread has a uniform pressure distribution in order to obtain uniform wear. With the arrival of high performance tires that have very low dimensional relationships, the use of belt structures with overlays of synthetic nylon or aramid cords has been common. In addition to achieving high-speed performance, the thickness of the tread has been kept to a minimum. The thick mass of the tread at high speeds simply wants to take off the tire [sic]. As these tires have pushed to limit the design of tires known to engineers, they have had to rethink all the parameters of the tire. In some cases these mean going backwards and to re-analyze the concepts that were used in the past but that were abandoned as a result of those used in the technique in search of a different path. A road that is necessary for engineers to consider is how to get more benefits from a lightweight tire without incurring the disadvantages of substantial cost of some of the tire components that have been used to achieve durability at very high tire speeds. more expensive for tourism use.

SUMMARY OF THE INVENTION A tire with radial layers 10, which has very light weight and low rolling resistance has an aspect ratio in the range of 0.2 to 0.8. The tire 10 has a pair of annular, parallel strings of the heel 26; one or more radial carcass plies 38, at least one radial layer of the carcass 38 being wrapped around the bead cores 26; a belt sture 36 positioned radially outwardly from the one or more radial layers of the carcass 38 in a crown area of the tire 10; and a superimposed layer 59 with a width substantially coinciding with the width of the belt sture 36. A tread 12 is positioned radially outwardly of the superimposed layer 59 and a side wall 20 is positioned between the tread 12 and the heels 26. The superposed layer 59 has filaments or cords 70, the cords 70 being selected from a group of materials that are preferably relatively non-shrinkable, the group being rayon, PET, aramid, PEN, or PVA embedded in an elastomer. The sture of the belt 36 is made of two layers reinforced with rayon cords 50, 51 having the angles of the cords a range of 16 ° to 28 °, preferably about 22 °. The material of the rayon cord is preferably 1840/2 to 2440/2/2, more preferably 2440/3 with an EPI of 18 to 30. The overlying layer 59 is preferably wound spirally in the radially outward direction of and adjacent to the belt sture 36. The superimposed layer 59 being made of a continuous band of reinforcement tape with an inch width of 1 inch with 4 to 45 parallel reinforcing filaments or cords 70 embedded therein. In the preferred embodiment, the strings of the superimposed layer 70 are aramid, however, the strings of high tensile strength, low thermal shrinkage such as rayon, PEN, PET or PVA can also be used. The tire 10 according to the invention has a very thin lower part of the tread 13, the lower part of the tread 13 being measured from the radially external surface of the cords 70 of the superposed layer 59 to the Full depth circumferential cleft. The lower part of the tread 13 with a thickness (t) less than 2 mm, preferably above 1 mm. To further improve the handling performance, the tire 10 employs a hard apex 46 extending radially outward from each bead core 26 and adjacent the layer 38. The apex 46 has a Shore D hardness greater than 50. To improve stability side of the tire 10, this can employ two inserts of the side wall, one insert being in each side wall 20. Each insert of the side wall has two layers 52, 53 of biased rope reinforcements. The strings of the first layer 52 oriented equal but opposite to the strings of the second layer 53, the two layers 52, 53 being interposed between the apex 46 and the upward bend 32 of the counterplate of the shell 38. The strings of each layer are oriented at an angle of 25 ° to 60 ° relative to the radial direction. Preferably, the first and second layers 52, 53 have a radially inner end 54 and a radially outer end 55, the respective ends 54, 55 of the one layer being staggered relative to the ends 54, 55 of the opposite layer. The radially outer end 55 of the one layer is located at about half the height of the SH section of the tire or a location h as shown. The tire 10 may further have a noise-dampening rubber band 42 below the belt edges and extending to approximately 50% of the height of the SH section of the tire 10. The cords 41 of the one or more housing counterplates 38 can be selected from the group of rayon, nylon, PEN, PET, steel or aramid. The preferred tire 10 used a counterplate of the rayon housing 38. The tire 10 using the novel combination described above can be made very light in weight at a moderate to very low cost compared to conventional tires having superimposed layers. The inventive tire 10 can demonstrate acceptable performance, particularly during handling with the additional benefits of very low rolling resistance.

BRIEF DESCRIPTION OF THE DRAWING Figure 1 is a cross-sectional view of one half of the tire 10 of the embodiment according to the present invention, the opposite half being of similar shape and construction. Figure 2 is a cross-sectional view of the low-cost version of the tire 10 similar to Figure 1.

Definitions "Relationship between dimensions" means the ratio of your section height to your section width. "xial" and "axially" means lines or directions that are parallel to the axis of rotation of the rim. "Heel" or "bead core" generally means that part of the rim that consists of an annular traction member, the heels radially Inner parts are associated with keeping the tire on the rim being wrapped by layers of cords and formed, with or without other reinforcement elements such as cutouts, pieces, apexes or fillings, risers and screens. "Belt structure" or "Reinforcement belts" "'means at least two annular layers or layers of parallel strings, woven or non-woven, below the tread, not anchored to the bead, and having left and right cord angles in the range from 17 ° to 27 ° with with respect to the equatorial plane of the tire. "Circumferential" means the lines or directions that extend along the perimeter of the surface of the annular tread perpendicular to the direction of the tire. axial "Shell" means the structure of the tire in addition to the structure of the belt, the tread, the lower part of the tread, on the layers, but including the beads. "Coating" means the carcass, belt structure, heels, sidewalls and all other components of the tire except the tread and the underside of the tread. "Screens" refers to narrow strips of material placed around the outside of the heel to protect the layers of the cords from the rim, distribute bending over the rim. "Rope" means one of the reinforcing threads of which the layers in the tire are composed. "Equatorial plane (PE)" means the plane perpendicular to the axis of rotation of the tire and passing through the center of its tread. "Footprint" means the area or contact area of the tread of the tire with a flat surface at zero speed and under normal load and pressure. "Inner lining" means a layer or layers of elastomer or other material that forms the inner surface of a tire without an inner chamber and that contains the inflator fluid within the tire.

"Normal inflation pressure" means the inflation pressure of the specific design and the load assigned by the organization of adequate standards for the state in service for the tire. "Normal load" means the inflation pressure and the load of the specific design assigned by the organization of adequate standards for the state in service for the tire. "Layer" means a layer of parallel strings coated with rubber. "Radial" and "radially" means the directions radially toward or away from the axis of rotation of the tire. "Tire with radial layers" means a pneumatic rim with belt or circumferentially restricted in which at least one layer has cords extending from the heel to the bead and are at corners of the strings between 65 ° and 90 ° with respect to the plane equatorial tire. "Section height" means the radial distance from the nominal diameter of the rim to the external diameter of the tire in its equatorial plane. "Section width" means the maximum linear distance parallel to the axis of the tire and between the outside of its walls when and after it has been inflated to normal pressure for 24 hours, but without load, the elevations of the side walls due to labeling, decoration or protective bands are excluded. "Shoulder" means the upper portion of the side wall just below the edge of the tread. "Sidewall" means that portion of a tire between the tread and the heel. "Tread width" means the arc length of the tread surface in the axial direction, ie, in a plane parallel to the axis of rotation of the tire.DETAILED DESCRIPTION OF THE INVENTION The tire 10, according to the present invention, employs a unique structure. The tire 10 as illustrated in Figure 1 is a radial tire for passengers or light truck; the tire 10 is provided with a tread portion for contacting the ground 12 that terminates in the shoulder portions at the lateral edges 14, 16 of the tread 12, respectively. A pair of sidewall portions 20 extends from the side edges of the tread band 14, 16, respectively and terminates in a pair of bead regions 22 each with an annular, non-extensible bead core 26, respectively. The tire 10 is further provided with a carcass reinforcing structure 30 extending from the heel region 22 through a sidewall portion 20, the tread portion 12, the opposite sidewall portion 20 to the heel region 22. The upturned ends 32 of the carcass reinforcing structure 30 of at least one radial layer 38 are wrapped around the bead cores 26 and extend radially outwardly to the terminal end 33. The upward bend 32 can finish at approximately the radial location of the maximum width of the section in the embodiment of Figure 1. The tire 10 may include a conventional inner lining 35 forming the peripheral inner surface of the tire 10, if the tire is to be of the tubeless type inside. In the preferred tire 10, the inner liner 35 is made of 100% broxyl or otherwise halobutyl. As shown in Figure 1, the tire 10 can employ a single synthetic layer wrapped over the bead core 26 and extending to a high upwardly folded end 33 located at approximately the radial location of the maximum diameter of the section (h). Positioned circumferentially around the radially outer surface of the carcass reinforcing structure 30 below the tread portion 12 is a belt structure reinforcing the tread 36. In the particular embodiment illustrated, the belt structure 36 it consists of two cut belt layers 50,51 and the cords 80 of the belt layers 50, 51 are oriented at an angle of approximately 22 ° with respect to the semi-circumferential center plane of the tire. The cords 80 of the belt layer 50 are positioned in a direction opposite to the semi-circumferential center plane and from this of the cords 80 of the belt layer 51. However, the belt structure 36 may consist of any number of belt layers. and the cords 80 may be positioned at any desired angle, preferably in the range of 18 ° to 26 °. An important feature of the layers 50, 51 is that each layer 50, 51 is a single cut layer, no layer having bent edges. The belt structure 36 provides lateral stiffness through the width of the belt to minimize the lifting of the tread 12 from the road surface during the operation of the tire 10. In the illustrated embodiments, this is accomplished by making the ropes 80 of the rayon belt layers 50, 51 and preferably having the following material properties of 1840/2 (twisted 6/6 to 12/12 tpi) up to 2440/2/2 (twisted 3/3 to 10/10 tpi) but preferably 2440/3 (twisted 6. 5 / 6.5 tpi) with an EPI of 18 to 24 and a cured angle of 16 ° to 28 ° after vulcanization, preferably of 22 °, having a density of 15-15 EPI of construction. The reinforcing structure of the housing 30 consists of at least one reinforcing layer structure 38. In the particular embodiment illustrated in Figure 1, a reinforcing layer structure 38 is provided with a double upward 32 of the layer radially. externally, this layer structure 38 preferably has a layer of parallel strings 41. The strings 41 of the structure of the reinforcement layer 38 are oriented at an angle of at least 75 ° with respect to the semicircifferential central plane CP of the tire 10. In the particular modality illustrated, the strings 41 are oriented at an angle of approximately 90 ° with respect to the central, semi-circumferential plane. The cords 41 are made of any material that is normally used to reinforce the rubber articles with ropes, for example, and not as limitation, rayon, nylon and polyester, aramid or steel. Preferably, the ropes are made of material having a high adhesion property with rubber and high thermal resistance. For the cords of housing 41, organic fiber cords with an elastic modulus in the range of 250 to 600 kgf / mm2 such as nylon 6, nylon 6-6, rayon, polyester or high modulus cords are commonly used. In the case of 340 to -2100dTex these fiber cords are preferably used in a density of 17 to 30 EPI. Another high modulus fiber includes aramid, vinylon, PEN, PET, PVA, carbon fibers, glass fibers, polyamides. Otherwise, it is possible to use steel steel cords with very high tensile strength with fine diameter filaments that exhibit excellent fatigue resistance. In the particular embodiment illustrated in Figures 1 and 2, the cords 41 are made of rayon. The cords 41 have an E modulus of X and a percent elongation of Y. The preferred rayon cord 41 has X values in the range of at least 10 GPa and percent elongations in the range commonly found in the specific material of the rope. As further illustrated in Figure 1, the bead regions 22 of the tire 10 each have first and second annular, substantially non-extensible bead cores 26, respectively. The bead core is preferably constructed of a single steel wire or monofilament wound in a continuous manner. In the preferred embodiment the high tension steel wire, diameter 0.038 inches (0.97 mm) is wrapped in four radially internal to radially outer layers of four wires, respectively, forming a 4 4 construction. Located within the region of the bead 22 and the radially internal portions of the sidewall portions 20 are the high modulus, elastomeric apex inserts 46 placed between the reinforcing structure of the carcass ply 38 and the ends and the bent up ends 32, respectively. The elastomeric apex inserts 46 extend from the radially outer portion of the bead cores 26 respectively, to the side wall portion gradually decreasing in the transverse width. The elastomeric inserts 46 terminate at a radially outer end at a distance G radially within the maximum width of the tire section at location (h) as shown in Figure 1. In the particular embodiment illustrated, the inserts of the elastomeric apices 46 each extend from their respective bead cores 26 at a distance G of about twenty-five percent (25%) of the height of the tire section. For the purposes of this invention, the maximum height of the SH section of the tire should be considered the radial distance measured from the nominal tire diameter DNLL to the radially outermost portion of the tread portion of the tire. Also, for the purposes of this invention, the nominal diameter of the rim should be the diameter of the tire as designed by its size.

In a preferred embodiment of the invention, the heel regions 22 further include at least one member reinforced with cords 52, 53 located between the apex insert 46 and the end of the bent upward layer 32. The member or members reinforced with cords 52.53 have a first end 54 and a second end.55. The first end 54 is axially and radially inward from the second end 55. The member or members reinforced with cords 52, 53 increase in radial distance from the axis of rotation of the tire 10 as a function of the distance from its first end 54. In Figure 1 illustrated, the member reinforced with cords consists of two components 52, 53 having a width of approximately 4 cm. The axially inner component 52 has a radially inner end 54 which is in the radial direction at or slightly above the first and second heel cores 26. The axially outer component 53 has a radially inner end that is radially outward from the outer surface of the core. of heel 26 by approximately 1 cm. The axially internal and axially external components 52, 53, preferably have reinforcements of rayon, nylon, aramid or steel cords, in the tire of the preferred embodiment, rayon cords 1400/2 dTex the second end 55 of the reinforced member was used. ropes 53 is located radially outwardly of the bead core 26 and termination 33 of the upwardly bent end 32 of the first layer 38, and is radially located at a distance of at least 50% of the height of the SH section measured from the nominal diameter of the heel. The cords of the members 52, 53 are preferably inclined at an angle between the sides relative to the radial direction in a range from 25 to 75 °, preferably 55 °. If two members are used, the angles of the strings are preferably equal but placed in the opposite direction. The reinforced member with cords 52, 53 improves the tire handling characteristics 10 of the present invention. Members 52, 53 greatly reduce the automobile's tendency to oversteer, a significant problem found in conventional tires that are driven when they are not inflated or under inflated. It is possible to add a cloth-reinforced member 61 to the bead regions 22 of the tire 10. The cloth-reinforced member has the first and second ends 62, 63. The member is wrapped around the first layer 38 and the bead core 26. Both the first and the second ends 62, 63 extend radially on and outwardly of the bead core 26. The side portions 20 of the tire of the preferred embodiment 10 are provided with a pair of first noise-deadening fillers 42. The first Noise damping fillers 42 are employed between the innerliner 35 and the reinforcing layer 38. The first fillings 42 extend from below each belt edge in the shoulder region of the tire 10 to radially within the end of the reinforced member 55. As illustrated in the preferred embodiment of the invention of Figure 1, the sidewall portions 20 each include a first sound-absorbing filler 42 and an apex insert 46. The first fillings 42 are positioned as already described. The apex inserts 46 are located between the first layer 38 and the upturned ends 32 of the layer 38, respectively. For the purpose of this invention, the maximum width of the section (SW) of the tire is measured parallel to the axis of rotation of the tire from the axially external surfaces of the tire, excluding markings, embellishments and the like. Also, for the purpose of this invention, the width of the tread is the axial distance through the tire perpendicular to the equatorial plane (PE) of the tire measured from the tire footprint inflated to the maximum standard inflation pressure. To a load classified and mounted on a wheel on which it was designed. The tire 10 illustrated in Figure 1 of the preferred embodiment has a fabric superimposed layer 59 placed on the belt structure of tread reinforcements 36. For example, two veneered layers having PEN, PET, PVA, rayon or aramid cords can be placed on each of the belt reinforcing structures 36, the lateral ends extending beyond the lateral ends of the belt structures 36. another way, a single layer of reinforced spiral wound fabric can be used as a superimposed layer. The tire of the preferred embodiment 10 used spirally wound aramid ropes 70, of the type 1670/3 or more preferably 1100 / 2dTex. The aramid material has a substantially higher modulus of elasticity than the rayon and, consequently, gives rise to a tire reinforcement stronger than two layers of nylon. Applicants have found that an increase in high speed capacity can be obtained in a tire with a single layer of aramid superimposed with at least 14 PPE, preferably approximately 17 PPE. In general, the use of the aramid material in passenger tire applications is avoided in part due to the fact that the material has poor noise properties that the sounds resonate through the relatively thin side walls of the passenger tire. The tire of the applicants of the present invention employs a noise absorbing insert 42 in the side walls 20 which appreciably dampens the noises generated by the tire. These noise-deadening side walls 20 allow the use of a superimposed layer of aramid without experiencing unacceptable noise levels. The cords 80 of the overlay 59 may otherwise be made of nylon, PET, PEN, or PVA. A PEN filament having a density of 240 dTex to 2200 dTex can be employed, more preferably of 1440 / 2dTex having twist of the yarn and ropes of between 4 and 12 tpi, preferably 7Z / 9S can be employed. The apex insert inserts 46, as shown, can be made from one or more other elastomeric materials. Preferred embodiments employed only one compound or material in the apex inserts 46 which extend from the core of the heel 26. The preferred material for the apex insert is very hard having a Shore D hardness of 50 or more, preferably of 50 to 55. The hardness of the insert 46 was obtained by cross-linked reinforcing resins mixed by a commonly known mixing procedure to achieve a high hardness that allows a minimum amount of material to be used to form the apex insert 46. Otherwise, the inserts 46 can be loaded with short fibers, which are preferably oriented at an angle of at least 45 ° to improve the radial and lateral stiffness of the insert, preferably the fibers are radially oriented. Preferably, the short fibers are made of textile or synthetic materials such as rayon, nylon, polyester or aramid. These short fibers can be directed radially or placed at inclined angles, preferably at least 45 ° but they should not extend around the circumference. The rubbing of the tire 10 in the lower region of the bead radially outwardly of the carcass structure 30 adjacent to the rim flange can be minimized, especially during the use of the tire in an uninflated state, by providing a hard portion for the rubbing of the rubber 60. The structure of the belt 36 has unfolded belts 50, 51 reinforced with rayon cords, which are preferably used from 1840/2 (torsion 6/6 to 12/12 tpi) up to 2440/2 / 2 (torsion 3/3 to 10/10 tpi), but preferably 2440/3 (torsion 6.5 / 6.5 tpi), at a density of 18 to 24 EPI. The belts 50, 51 had a width of about 98% of the width of the cords for the tread of the mold commonly known as the width of the archwire of the tread. To further improve tire performance 10 and light weight characteristics, the tread 12 was built with a minimum gauge or thickness (t) of the lower part of the tread 13. Traditionally, for passenger tires, high performance, the lower part of the tread is reduced to between 2 and 5 mm. The tire of the present invention had a lower tread portion of less than 2 mm, preferably approximately 1 mm measured from the radially outer ropes 70 to the superimposed layer 59 to a lower part of the full depth circumferential groove as shown in FIG. shown in Figure 1. To ensure that the inventive tire 10 reduces the inherent stresses created when molding a tire having rayon belts 50, 51, it was determined that the mold should be wide and flat in the band of rolling. The tread radius of 315 mm and a width of the tread of 141 mm tread were evaluated with acceptable results. In a tire size of 195 / 65R1Í 91V, a tread radius of 914 mm and a tread width of 152 mm produced much better results. The inventors consider that a radius for the flat tread greater than 300 mm over a tread width of about 125 mm or more will provide acceptable results. More preferably, the radius of the running surface R must be greater than 500 mm for a width of the tread of the tread greater than 150 mm, more preferably R must be at least 750 mm. This wide, flat tread arch allows the belt cords 80 to undergo minimal deformation with thermal shrinkage which could deform the cords of the layer 51 adjacent to the carcass ply 38. It is in combination with the cords of the belt. the low thermal shrink layer 41 and a similarly low superimposed heat shrink layer 59 means that the tire 10 can be manufactured and placed in use so that the overlying layer 59, the layer 38 and the belts 50, 51 will withstand exposure to thermal expansion and contraction without damaging deformations. A tire for the control of the test with the size 195 / 65R15 91V was made with the conventional steel belts, the weight of the tire was 9.4 Kg. The tire of the same size was made according to the present invention and had a weight of approximately 7.1 Kg, depending on the adjustment of the tire 10 to the weight when the concepts of the invention described above were used, have produced weights in the range of 6.7 to 7.4 Kg. This weight reduction was a very beneficial improvement over the prior art since it reduces the contribution of the kinetic energy of the tire, decreasing the translation and rotation energy and thus reducing fuel consumption.

In addition, the reduced weight of the tire mass without suspension allows car manufacturers to redesign the suspension with reduced weight components to improve the car's weight, performance and handling. The tire of the present invention performs an improvement in rolling resistance of 10% to 18% compared to the control tire of a classic construction made in the same mold with the same tread compound and a standard steel belt. Improvements in the tread from 0 to 10% were observed in the normal wear test of tire 10 compared to conventional construction. The tire 10 less sensitive to wear at the position of the wheel was observed. The shoulder wear of the steering position and the wear in the center line of the rear wheel position when loaded lightly were much less pronounced in the inventive tire 10 when compared to the prior art tires. The flat portions of the inventive tire were much better on prior art tires in terms of the amount of time needed to recover the disturbance-free performance feature. Flattening is a state that commonly occurs when a vehicle after being driven is parked causing the hot tire to cool so that the structure has a tire structure that is locally flattened. More importantly, the inventive tire has excellent demonstrated durability and has passed the hammer test, carcass fatigue with durability on the road, outdoor resilometer, brake impact test, road pressure contact and the DOT and ECE R30 qualification tests legally required. As shown in Figure 2, the tire 1 can be manufactured at an even lower cost by eliminating the reinforcements 52, 53 and the noise-absorbing insert 42 f In addition, the cords of the overlying layer 70 can be of lower cost rayon with regard to to the use of aramid. 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 may be made therein without departing from the spirit or scope of the invention.

Claims (22)

1. A pneumatic tire of radial layers having a ratio between dimensions of 0.

2 to 0.8 consists of a pair of annular, parallel heels, one or more radial layers of the carcass, at least one radial layer of the carcass having a pair of folds being wrapped around the heels, a belt structure positioned radially outwardly from the one or more radial layers of the carcass in a crown area of the tire, and an overlying layer having a width substantially coinciding with the width of the belt structure , a tread radially disposed outwardly from the overlying layer, and a sidewall positioned between the tread and heels wherein the superimposed layer consists of reinforcing strands or cords, the strings being selected from a group of materials, being the group rayon, PET, aramid, PEN, or PVA embedded in an elastomer, and being the structure of the belt made of two or more layers reinforced with rayon strings having the angles of the strings in the range of 18 ° to 26 °. The pneumatic tire of claim 1, wherein the overlying layer is spirally wound radially outwardly from the belt structure and consists of a group of elastomeric reinforcing tape strips having a width of half an inch & 1 H inches and 4 to 45 filaments or reinforcement cords embedded in it.

3. The pneumatic tire of claim 1, wherein the reinforcing filaments of the superposed layer are PEN filaments having a density of 240 dTex to 2200 dTex.

The pneumatic tire of claim 2, wherein the PEN reinforcement cords have a torsional multiplier of 5 to 10.

The pneumatic tire of claim 3, wherein the reinforcement of PEN is 1440/2 dTex strings that have a thread and twist of the rope between 4 to 12 tpi.

6. The pneumatic tire of claim 1, wherein the reinforcing filaments of the superimposed layer are aramid.

The pneumatic tire of claim 5, wherein the reinforcing filaments of the superimposed layer are 1100/2 dTex flexten.

The pneumatic tire of claim 6, wherein the filaments have one end per inch (EPI) of about 15 to 30.

The pneumatic tire of claim 1, wherein the tread has a lower part of the tire. tread measured from the radially outer surface of the cords of the superposed layer to a full depth circumferential groove, the lower part of the tread having an average thickness of less than 2 mm.

The rim of claim 8, wherein the lower portion of the tread has a thickness of about 1 mm.

11. The rim of claim 1, further comprising an apex extending radially outwardly on each of the bead cores and adjacent to the layer, the apex having a Shore D hardness greater than 50.

12. The rim of the claim 10, further comprises two inserts of side walls, an insert in each side wall, each insert being two elastomer layers reinforced by biased cords, a first layer being oriented equal but opposite to the second layer, the two layers being interposed between the apex and the fold up of the shell layer.

The rim of claim 11, wherein the first and second layers have biased rope angles of 25 ° to 60 °.

The rim of claim 12, wherein each first and second layer has a radially inner end and a radially outer end, the respective ends of a layer being staggered relative to the ends of the opposite layer, the radially outer end of a tire being located at approximately half the height of the section of the rim

15. The rim of claim 1 further comprises an inner lining of a noise-absorbing elastomeric insert., the insert being between the inner lining and the layer below one edge of the belt and extending to approximately 50% of the height of the section of the rim.

16. The pneumatic tire of claim 1, wherein the shell layers have radial rayon cords.

17. The pneumatic tire of claim 1, wherein the shell layers have radial nylon cords.

18. The pneumatic tire of claim 1, wherein the shell layers have PEN radial strings.

19. The pneumatic tire of claim 1, wherein the shell layers have radial aramid ropes.

20. The pneumatic tire of claim 1, wherein the shell layers have radial steel cords.

21. The pneumatic tire of claim 1, wherein the rayon cords of the belt structure are of a material of 1840/2 through 2440/2/2.

22. The pneumatic tire of claim 21, wherein the rope layers of the belt structure have a density from 18 to 24 EPI.