PL95360B1 - PNEUMATIC TIRE AND CYLINDRICAL TIRE FOR THE MANUFACTURING OF PNEUMATIC TIRE - Google Patents

Abstract

1477210 Pneumatic tyres MICHELIN & CIE (COMPAGNIE GENERALE DES ETABS MICHELIN) 11 June 1974 [12 June 1973] 25912/74 Heading B7C A pneumatic tyre comprises at least one parallel cord carcass ply, the cords of which form an angle of 70 to 90 degrees with the circumferential direction in the sidewalls and in the crown a smaller angle with the circumferential direction, and three superposed oblique parallel cord breaker plies making respective angles with the circumferential direction, wherein the direction of the cords of the breaker ply next adjacent the carcass differs by at most approximately 30 degrees from the perpendicular to one diagonal of a parallelogram with sides parallel to the cords of the other two breaker plies, the other diagonal being parallel to the circumferential direction. As illustrated in Fig. 3, angles α, #, γ are + 23, - 16, and + 31 degrees respectively. The embodiment of Figs. 4 and 5 comprises a rayon cord carcass ply 1, and a breaker consisting of a rayon cord ply 53, a polyvinyl alcohol cord ply 4, and a steel cord ply 5. Initially the plies are wound in a cylindrical drum with cord angles #=80 degrees (the carcass ply has same cord angle over its whole width prior to shaping), α= +38, #= -31, γ= + 73 degrees. After shaping (with the tyre diameter being 1À5 times the diameter of the cylindrical blank) the cord angles were #= -55¢, α= +23, # = - 16, and γ= +31 degrees. Rubber strips 55 are positioned beneath folded edges 54. [GB1477210A]

Description

The subject of the invention is a pneumatic tire on a structure similar to that described in French Patent No. 1,413,102 and cylindrical blank intended for production pneumatic tire. 9 In principle, the reinforcement of such tires includes them the bottom side is a warp of continuous wires or cables from feet to the foot, arranged radially along the sides and obliquely in the front area of the tire. In the zone The front end of the tire also contains reinforcement next to the parts twill warp, the second layer of cord threads with diagonal wires or cables crossing the wire backbones or cables of the replaced part and end in the forehead area of the tire.

Such reinforcement is easy to manufacture and can be used has the advantage of securing a continuous armor connection sidewall with reinforcement of the front tire. Also, the sides have the same flexibility as elasticity Completely radius carcass pneumatic tire new, that is, radial from the foot. This no less under certain conditions, forehead reinforcement my tires are insufficient. Therefore, the solution according to the cited French patent, ra amplification by adding at least one a further layer of twisted wires or cables lurking in the area of the forehead of the tire. Inconvenience this solution is that this amplification can not be attached until the base has been shaped warp. However, the basic structure of such pneumatic tires are commonly used at least one continuous layer from foot to foot, when orienting the wires or cables with a deviation of up to 20 ° in relation to radial direction in the side area, at keeping the bevel in the front area of the tire.

The object of the invention is to develop a tire pneumatic with the strengthening of the front of the tires on a specific primary, preserving space properly under all rolling conditions itself and enabling the shaping of a cylindrical half of the product after its completion.

The invention is based on the one hand on analysis the stresses of the elements running on a parallelogram mentary selected in the front tire reinforcement.

This elementary parallelogram has, conventionally, a trans angle parallel to the circular direction and long guests of equal unity; moreover, the opposite sides are parallel to the wires or cables of the pair crosswise oblique backing layers. IN such a parallelogram of stress stretching the division flowing in the circumferential direction are evoked cast by compressive stresses on the second switch katnej. On the other hand, it is known that wires and cables are generally adversely affected compressive axial stress. Therefore, in solution According to the invention, the principle was introduced stiffening of the front tire reinforcement.

The solution according to the invention introduces v reality, the impact of the above-mentioned zen compression crossbars for wires and cables 953603 95360 4 a third backing layer, with the wires and the cables are arranged diagonally longitudinal plane of the elementary parallelogram under the canal at least 30 ° perpendicular to the elevation changed diagonal.

Thus, the invention relates to a pneumatic tire, which reinforcement includes from inside towards at least one layer of wires on the outside or continuous cables from foot to foot, forming with circular direction, one side on the sides, angle- included between 70 and 90 ° and on the other side, in the area of the forehead, an angle smaller than the angle you create throws those wires or cables in the sides so that three on overlapping wire underlays or diagonal cables ending within the reach of the forehead, they cross at angles a (alpha), p (beta) and y (gam¬ ma) in relation to the circumferential direction. Tire this is characterized by having an angle (alpha) layer the backing adjacent to the matrix is bonded with angles p (beta) and y (gamma) of the base layer ... tgp —tgy —2tgatgptgY, by expression —— —- 2tgp tgy + tga (tgp-tgy) whose absolute value is less than 0.6.

According to the above performance feature they stiffen for the undercoat with an angle (al¬ fa).

The principle of stiffening according to the invention allows preferably reduce the total cross-section of the wires or cables per unit of the width of the backing layer an angle (alpha), with wires and cables being substantially transversely oriented, for example by reducing the number of wires or cables or cross-section of individual wires or cables.

Moreover, the stiffening layer covering the half of the Medium warp also enables security inclination of the wires or cables of the side facing side of the warp, as will be explained in more detail in the following part of the description.

Katy P (beta) and y (gamma) are basically less greater than 45 ° and preferably between 15 and 35 ° and there are two cases here. In the first time case, the angle p (beta) and y (gamma) are of characters opposite, the positive sign is accepted with this trigonometric sign we consider when longitudinal as basic. In this case towards kat a (alpha) has the sign of two angles p (beta) i y (gamma) i whose absolute value is the greatest bigger. In the second case, katy p (beta) and y (gamma) have the same sign. Thus, the sign of kata a (alpha) is always opposite to the characters p (beta) and y (gamma) angles.

Where p (beta) and y (gamma) have ite value itself, it is understandable that according to ex the invention, the alpha angle may be selected in value positive or negative to the direction perimeter, provided that the pattern is met presented above.

A frontal reinforcement according to the invention may have edges reinforced, for example, by a crease cut the edges of the p (beta) layer around the edge of the y-angle (gamma) layer as it is before in French Patent Nos. 1,437,415 and No. 1,427,886 granted to Michelin. This one The design is suitable for the tires intended connected for the equipment of high-speed vehicles.

According to another embodiment in the solution According to the invention, there is a degree of the width of the three backing layers. Ko¬ Preferably, it is chosen as the layer of the narrowest layer a (alpha) angle is adjacent to the matrix. In this way, elbows of wires or cables connecting matrix sections placed on the sides with sections put beneath the (alpha) angle layer are covered these by the protruding edge zones of the angle layers P (beta). This position makes it easier to keep the slant wires or cables of the appropriate zone of reinforcement carcass, for example, when the tire is Does it happen with high speed. Solution according to this of the example embodiment can be combined advantageously not one pair of layers with folded edges, what is described later in the description.

It is understandable that the invention and its examples execution includes forehead reinforcement, width and / or angles adapted to different layers, like also the frontal reinforcement of the phenomenon and / or structure asymmetric and reinforcement formed by part overlapping forehead reinforcements with or without linkage in the transverse direction.

To make a pneumatic tire with a construction according to the invention, creating a complete cylindrical blank on drum for confectionery. This production consists of generally on the carcass position continuously from the foot to the foot, successively backing layers with angles a (alpha), p (beta) and y (gamma), then on the cover There are, if any, the reinforcement on the sides and on the run rubber. The manufacturing activity may be performed inside the vulcanization mold or on outside the mold if all ingredients are mouth lone, but in any case after completion to produce all the reinforcement, it is left on need a certain freedom of movement for the feet. * o According to the basic principle of solving the e¬ invention debt wires or cables of the stiffening layer najacej (at angle a (alpha) are arranged almost perpendicular to the tunic of the tensions sSkumczliiWy disappearing from the shaping of two other layers 45 podikladoiwyclh (o fcaltatih p beta and y gaimima). Toroz ^ it also leaves a layer on the angle the (alpha) freedom necessary to fit on the course adjusting the angle of wires or cables in the zone adjacent to the carcass underneath. Preferred Process for Manufacturing Pneumatic Tire According to the invention, the function is positioning different layers of primer in this way, with shrinkage an elementary parallelogram corresponding to pa¬ roughening layers of the p (beta) and y (gamma) primer 55 is greater than or at least equal to the contraction an elementary parallelogram corresponding to pa¬ contiguous layers on the underside. This couple is formed by a stiffening layer at the angle a (alpha) and through the warp. o. Assuming that the matrix has an angle of 8 (delta), the shaft the above market is expressed as the following ratio between the angles of the four layers in the forehead of the tire. 63 tga + tg6> tgp + tgY95360 6 or tga + tg8 > \ tgp + -tgy Preferably the value of the expression is from 1 to 4. Despite the reinforcement of the reinforcement in the front of the tire According to the invention, pneumatic tires are provided provides considerable comfort. You can assume that you get it is mainly due to the inclined section matrix wires or cables in the forehead area, but also that wires or cables are wrapped around the wheel lana to reduce impact. In case of when the a (alpha) angle primer adheres to the warp is narrower than a pair of backing plies adjacent to the top with angles p (beta) and y (gamma), is a layer of rubber which is preferably applied to the ground between the edge portions of said pair of layers backing and the warp also contributes to tread-borne shock absorption.

Preferred values for the width of the primer layer entrance adjacent to the carcass are between 50 and 90% of the average width of a pair of backing layers lying above, with the optimal range the values lie between 70 and 75%.

The subject of the invention is described by way of examples versions illustrated in the drawing in which . Figures 1A to ID show graphically the method bu ordering an angle (alpha), in value and sign, value backing seams adjacent to the carcass in accordance with the main characteristic of the invention, while what the p (beta) and y (gamma) angle are given, fig. 2 - in a radial section, and fig. 3 - a view, in the radial direction, with a section of parts a pneumatic tire according to the invention, fig. 4 is a radial section, and Fig. 5 is shown in Fig schematic dock in the plane towards radial segment of a pneumatic tire v invention, and having a reinforced belt edges.

The method of graphical representation of kata a (alpha) of the backing layer adjacent to the reinforcement of the matrix it consists in drawing a parallelogram of the element diagonal parallel to the direction longitudinal tire. A selection is made for this purpose (Fig. 1A to ID) any unit width BC any on the basis of parallel to the longitudinal axis XX, not in front of it shown in the figure, then diagrams with point B straight line BD forming an acute angle p (beta) with diagonal BC and equal to the angle of the second layer then create a CD line from point C acute angle y (gamma) with diagonal BC i equal katoiwi fc of the third subclass layer. These two are simple intersect at point D. It is then set at diagonal BC of point A, in the middle of segment BC.

The second diagonal of the elementary parallelogram goes through points D and A. Just then plot from point A normal line N to pro¬ stej DA. Sharp angle of the straight line N with diagonal BC is the desired angle of a (alpha) which is preferred it should not be more than 30 °.

Basic account allows you to check if between angles a (alpha), p (beta), y (gamma), fig. tgp —tg7 40 45 50 55 1A to ID, there is a relationship tg a = - whichJ with tgp tgY allows to determine the optimal value of angle a (alpha), 05 where cat p (beta) is different from kata Y (gamma).

For, to determine the contraction transmitted by the elementary noleglect corresponding to the pair layers with p (beat) and y (gamma) angle, for example in the process of adjusting the cylindrical blank tires according to the invention, it is enough to calculate d (BC) sunek, where d (BC) is a differential, v d (2DM) dependence on angles p (beta) and y (gamma), length BC diagonal parallel to the longitudinal direction elementary parallelogram / Also d (2DM) there is a difference depending on the angle p (beta) and y (gamma), with a width of 2 DM of a parallelogram el mental with respect to the transverse direction, with what DM is the normal lead width top D on diagonal BC. Tensoconstriction equal to - \ (tgp + tgy).

It can also be assumed that the contraction resulting on an example of adjusting a parallelogram to an element corresponding to a pair of undercoat layers at angles (alpha) and 8 (delta) underlay the dome is adjacent to the carcass and the warp is equal - Htga + tgo).

Advantageous variation of the method of manufacturing "tire according to the invention it consists in the arrangement of the roses different layers thus, with the contraction of the pairs of layers for p (beta) and y (gamma) angles greater than or at least equal to the shrinkage of the layers with angles a (alpha) and 8 (delta). Using the expression po¬ higher leads to dependency presented above and above tga + tg8> tgp + tgy.

Figures 2 and 3 show the tire according to the invention of a strip whose reinforcement comprises a matrix and a continuous link fixed in feet 2 by wrapping on a pin 6, and three layers of primer 3, 4 and 5. Fig. 3 shows that, in a particular case, it has been solved warp 1 has a zone under the forehead lem in which wires or cables strengthen it Rza cat 8 (delta) with the longitudinal direction XX.

On the sides, the wires or cables of the matrix 1 are, for example clade depicted, practically distributed radially. Wires or cables of three layers of backing clades 3, 4 and 5, superimposed in order counting from warp 1 creates sharp angles accordingly a (alpha), p (beta), y (gamma) with longitudinal direction nym. Their opening is limited by the reach of the forehead la. In the example described, the angles of the underlayment layers The 4 and 5 measurable values are as follows: p (beta) = = -16 ° and y (gamma) = 431 ° with the sign to datni is the adopted trigonometric sign / The underlayer 3 is set at an angle a (alpha) of 423 ° to the direction circular.

In this case, the expression tgp - tgy - 2tga tgp tgy 2tgp tgY + tga (tgp - tgY) is equal to 0.3 and the optimal value for angle a (alpha) is 40—. In Figures 4 and 5 the same is used numerals for the same parts of the grades the ones represented in ffig. 2 13. It should be noted see that the tire according to the invention, shown in 95360 in these figures, it has frontal reinforcement including on one side, layer 53 (at angle a) of the attachment point The carcass is stiffer than other primer layers 4 and 5 forehead reinforcement. On the other hand, a layer sub-base 5 (angle y) is covered by the boundaries 54 undercoat laying underneath 4 (angle (3). Preferably, the rubber pads 55 are placed on both sides of the narrow base layer Kladowa 53.

The tire is shown schematically in the figures 4 and 5 with dimensions 165-380 was produced of the following reinforcement elements: - warp: 1880/2 polyamide threads, (118 threads per decimeter) placed on the packaging drum at an angle of -80 °, distance between legs: 366mm; - first backing layer 53: stainless threads rayon 1840/2 (50 twisted ni¬ ci per decimeter), width: 162 mm, superimposed at an angle of + 38 °; - rubber tread 55; width 27 mm; - second backing layer 4: alcohol thread polyvinyl 1330/2/2 (54 strands per dec meter), width: 340 mm, fitted at an angle —31 °; - 3rd backing layer 5: cord threads steel, 4-wire 23/100 mm + 1 braid wire reinforcement (63 threads per decimeter) wide bone: 210 mm, applied at an angle of + 73 °.

The periphery 54 of the second backing layer 4 is permanently applied to the third base layer 5, then the reinforcement set was covered with rubber covering the sides and tread, then adjusted up to a profile index of 1.5 which means that the diameter of a shaped tire is 1.5 times the diameter of the circular blank.

After shaping, the angles in the forehead area were na tap dance: - skeleton layer: - 55.5 ° (6) delta, - first forehead: + 23 ° (a) alpha, - second forehead layer: -16 ° ((3) beta, - third forehead layer: + 31 ° gamma.

In this embodiment, the ratio tga + tg8 tg (5 + tgy before forming, it is equal to 1.7.

Claims (9)

Patent claims 1.A pneumatic tire, the reinforcement of which includes, from the inside to the outside, at least one layer of wires or cables extending from the bead to the bead, forming a carcass reinforcement and forming in a circular direction, on one side on the sides, an angle between 70 and 90 ° as on the other side, in the forehead zone, an angle smaller than the angle that forms these wires or cables on the sides, as well as three layers of overlapping wires or cables that are oblique and confined to the forehead zone and forming sharp angles a (alpha), p ( beta) iy (gamma) with a circumferential direction, characterized in that the angle a (alpha) corresponding to the backing layer (3) adjacent to the matrix (1) is according to the expression 8 tgP - tgy - 2tgq tgp tgy 2t @ ptgY + tga (tgP - tgy) in absolute value, less than 0.6, where 5 0 (beta) and y (gamma) are the angles corresponding to two other backing layers (4, 5). 2. Tire according to claim The method of claim 1, characterized in that the wires or cables of the undercoat (3) adjacent to the carcass (1) form an angle (alpha) perpendicular to the perpendicular to the diagonal (D-A) parallel to the circumferential direction of - towards a unit with sides parallel to the wires or cables of two other backing layers (4, 5), the diagonal (B, C) parallel to the circular direction having a length equal to one. 3. Tire according to claim The method according to claim 2, characterized in that the wires or cables of the backing layer (3) adjacent to the carcass (1) form an angle α (alpha) with a circumferential direction in accordance with the expression 20? tga - practically equal to zero. 2tgp - tgY 4. Tire according to claim A method according to claim 2, characterized in that the wires or cables of two other backing layers (4, 5) form angles of less than 45 ° with the circumferential direction (B, C) and preferably comprised between 15 and 35 °. 5. Tire according to claims 3. The armature of claim 1, characterized in that the frontal reinforcement has reinforced flanges. thirty 6. Tire according to claim A method as claimed in claim 1, characterized in that the wires or cables of the undercoat (3) adjacent to the carcass (1) have a total cross section per unit width smaller than the cross section of the wires or cables of other wrapping layers placed in the forehead region. 7. Tire according to claim The backing layer of claim 1, characterized in that the backing layer (53) adjacent to the carcass (1) is thicker than the other backing layers (4, 5), its width being between 50 and 90 ° and preferably around 70 to 75 °. of the average width of two other backing layers, the missing parts of said backing layer being replaced by rubber (55). 8. A cylindrical semi-finished product intended for the manufacture of a pneumatic tire, characterized in that it has a warp (1) of wires or cables extending from one bead (2) to the other bead and forming an angle between 70 and 90 ° with the direction of peripheral as well as three backing layers (3, 4, 5); (53, 4, 5) the angles of which are defined by the expression tgp - tgy - 2tga tg | 3 tgy 2tgp tgy + tga (tgp - tgy) 55 with an absolute value, less than 0.6, where the angle a (alpha) is the angle formed by the wires or cables of the backing layer (3; 53) adhering to the carcass (1). 9. Semi-finished product according to claim 8, characterized in that 60 8 (delta) is the angle of the warp (1) of wires or cables extending from the flange (2) to the flange tga + tg8 (2) and its value determined by the ratio ¦ tgp + tgy is at least equal to 1, preferably comprised between 1 and 4.95360 Fig. 2 ki95360. * Fi National Printing House, Factory No. 6, order no. 917/77 PLN 45.