DE2206516A1 - RADIAL LAYER TIRES FOR VEHICLES - Google Patents

Description

PATENT LAWYERS ~

DR.-ING. R. DÖRING DIPL.-PHYS. DR. J. FRlCKE

BRAUNSCHWEIG MUNICH

Uniroyal SA,
Clairoix 60, France

"Radial Layer Tires for Vehicles"

The invention relates to a radial layer tire for vehicles, consisting of a carcass with at least one layer of reinforcing material, the elements of which are essentially in the radial direction from at least one reinforcement ring of the one tire bead to at least one reinforcement ring of the other tire bead and which has edge portions that surround the reinforcing rings on the outside are laid around, and of at least one reinforcing strip of woven material for each bead of each has a portion which, with respect to the reinforcement ring, is outside the carcass ply around the associated bead ring is beaten.

In the following, the term "cord" is used to encompass threads, yarns, filaments, wires, cables, tapes, Strands or the like.

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The carcass of a pneumatic tire is composed of one or more layers of coated with rubber the cord fabric consisting of Kordelementen, which extend substantially '■ parallel to each other in each layer. These layers are arranged one on top of the other and extend from one bead to the other, wherein in the region of the beads they are folded outwardly around each bead ring in order to form a bead reinforcement. In a radial ply carcass, the cord elements in each ply of the carcass are arranged essentially in radial planes which pass through the axis of rotation of the tire. In this way, the cord elements are substantially perpendicular to the circumferential direction of the tire. The carcass can be reinforced by one or more strips of fabric, which are covered by rubber; Layers of wire can be made and which form a reinforcement belt, for example, at least in the circumferential; direction is inextensible. A rubber layer, which forms an adhesive coating on the layers, can be arranged between the layers. Metallwulstdrähte which are embedded in the rubber, are usually wrapped generally each \ by a strip, each of which has along its ümfangslänge a rubber packing which forms a shell or a tip. Each bead ring is together with his-; A cap encased in a narrow bulb support strip known as a flipper. The flipper is folded back radially outwardly around the strip so that the latter is provided with a flap which

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allows secure attachment to the carcass.

In addition, each bead can have a narrow tear-off tear strip which is mounted on the outside of the carcass in order to protect the carcass against wear due to frictional damage.

to protect the edge of the rim shoulder. '

In a known type of radial layer tire for vehicles Every desert flag strip is used in support of the Bead arranged within the folds of the carcass layer or layers, which nerumge j to the outside around the bead ring

are beat. Each flap directly encloses the bead ring attached to it and covered with its crown. j Furthermore, there is an abrasion protection strip between a rubber, layer on the side and the turned back end of the card! cash layer or layers arranged and extending at least substantially over the height of the rim shoulder. This type of known embodiment has the disadvantage that the ends of the threads or wires which are each contained in the fabric of the carcass layers and the flaps, which form the flap, terminate freely at the edges of these fabrics, which are generally at different altitudes are arranged so that they tend to separate or loosen the layers and coatings. It is therefore desirable the least possible number of threads or To let the wire ends run out freely in this way.

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In another known type of radial ply tire, for example, the carcass has an inner carcass ply which is wrapped around each bead ring back to the outside while an outer carcass ply is back is wrapped around the inside of the bead ring. the Corresponding parts of the inner carcass layer as well as an abrasion protection strip are on the outside against the outer carcass layer applied in the area of each bead ring, with no flipper to support the bead is provided. In another known type of radial ply tire, the carcass comprises two carcass layers, namely, an inner and an outer, which are arranged as in the example described above. However, this is missing an abrasion protection strip. Furthermore, flaps are provided which surround each bead ring with their crown and which located within the palte of the inner carcass ply

I which runs around each bead ring. After all, a J

Another type of radial layer tire is known, the structure of which is the result of a combination of the two previously described benen known tire is. He also has two | Carcass plies, namely an inner and an outer anti-abrasion strip as well as flippers. The latter two types have the same disadvantages as the previously described types of tires.

To overcome these drawbacks, it has been proposed to eliminate the flippers as in the particular type that

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has been described above in order to reduce the risk of stratification

avoid separation. Due to the lack of flippers, j however, the disadvantages that the bead no longer has sufficient rigidity. That means he's got a specific Degree of flexibility or elasticity with respect to j lateral deformation, which is on the one hand i by a certain inertia or fatigue capacity of the tire-i body and, on the other hand, poor road traction while driving straight ahead and cornering. Additionally lies a kind of shift during the periods of the i

i Starting and accelerating as well as braking before which on a relative circumferential displacement of the beads, based on the outer circumference of the tire tread. These Displacement occurs in one direction during takeoff or acceleration and in the opposite direction during of the braking process. It has been suggested that this j

To avoid the disadvantage that the lateral flexibility of the bead rings by using bead flags similar,

j Removed support strips for the beads, which are made of interwoven j

I threads or wires and which extend over a certain ' extend radial height to increase the rigidity of those parts of the carcass which are adjacent to the beads. the The above-mentioned relative circumferential displaceability can then no longer occur on the beads. However, this shift occurs in higher lying or radially further outward areas in an intermediate position between the beads and the crown circumference area of the tire, so that the rela-

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tive extensive displacement at these points becomes smaller

than that of the bead rings, in the absence of a flipper; similar support strip occurs. This solution, however, solve the drawback of the risk of detachment of the flipper-like '■ support strip which tends to be more rapid; the higher the flipper strip runs or the further it extends radially outward from the bead rings. This strip has to stiffen the effect of the sidewalls of the tire, namely, for example, to the cross-sectional center height is obtained so that, although the flexibility of the side walls main- ', but only between the portion of the tread [and the mean height of the side walls. \

It is the object of the invention to overcome these difficulties in air

avoid tires for vehicles. ;

This object is achieved according to the invention in that at >

a tire of the type specified in the opening paragraph, the turned-around portion of the or each reinforcing strip is longer than the turned-back portion of the carcass ply and that the end of the longest of the folded portions of the or each reinforcing strip between the associated bead and the center height of the radial cross-sectional height of the tire j. The tire also includes a reinforcement belt which extends substantially in the circumferential direction of the tire over the carcass ply, and tread and sidewall portions of elastomeric material which extend over the carcass.

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are in cash.

The improved arrangement has the advantage that the behavior of the tire tread in the longitudinal direction and side ^! direction significantly improved. This is achieved by;

that essentially the relative displacements in the longitudinal direction;

or circumferential direction and the lateral flexibility of the 'bead areas are reduced, while at the same time the _i

Risk of dissolution or separation is reduced by '

ι that abrupt changes in stiffness are avoided, ■

which is the cause of the separation of the cord and rubber layers |

i th and even for breaking or splicing the cord-!

elements at the ends or edges of the cord layers leads. In the known tires, this risk is particularly common with the Layers each closest to the flap. The new arrangement also has the advantage that everyone of the above-mentioned bead reinforcement strips at the same time Function of the flap and the abrasion protection fulfilled, so that both can be eliminated while at the same time reliably securing the tire to the rim edges is ensured. In addition, it makes the arrangement according to the invention possible, a significant disadvantage of hose Eliminate loose tires. These are tires in which the abrasion protection strip surrounds the bead ring and on the outside between the sidewall rubber and the outer one The crease of the carcass ply is arranged, while on the inside the abrasion protection strip is the inner impermeable

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Rubber layer covering the tire. This known arrangement has the disadvantage that the pressurized air in the pneumatic \

Table tires tend to get into the fabric layer or the covers penetrate, especially in the area between j

the protective strip and the inner rubber layer on the one hand: side as well as between the carcass and the outer side wall rubber layer. Penetration occurs through the abrasion protection strip. This penetration of air results in the tendency for the layers to separate and thus for air to escape! increases. The result is a pressure drop which leads to a Schlaffwer-] to the tire. The arrangement according to the invention makes _; it possible to effectively eliminate this disadvantage by

ί on the one hand, the mechanical strength and \

Ability of the tire is increased, while on the other side

te is the resistance to the internal pressure of the compressed I

Gas is improved.

As will be explained in detail below, according to the invention, both parts are in a radial cross-sectional plane the fold of the above-mentioned reinforcement strip and the outermost outermost, folded-back portion each Carcass ply of a length different from each other so that the three respective extreme edges of both Portions of the crease of each strip and the extreme outer, folded back portion of each carcass ply in different heights are arranged, which between the bead ring and the mean height of the radial cross-section of the

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Lying on the tire.

Furthermore, each suitably comprises bead reinforcement strips in a known manner, a woven material, which consists of cord elements or individual threads, the two-

For example, form a regularly woven material with a.

Plain weave, for example of the single type. This ; Fabric is either made of a synthetic material, plastic or similar artificial material, such as nylon rayon or fiberglass, or of a metal, for example steel or aluminum, or of a padded material that
on the above components or on a combination of these
Components is based.

The weft threads and warp threads can either both on the one hand
from cord or both from single threads or on the other
Side either both made of the same material or one
from one and the other from a different material
exist. Because of these different composition options, which can be used either separately or in different combinations, the rigidity
and selectively vary the extensibility of the woven material

to adapt to the optimal application conditions. j

I hold. !

The invention also relates to a method for Her- ι

position of the new pneumatic tire. The procedure consists of the we- ■

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essential from the steps that successively the different j

different carcass layers and chafer in the shape of circular Ribbons are wound onto a rotating drum, which is a manufacturing cylinder that the bead rings applied to the circular belts previously built up on the drum and the ends of the layers; and wrapping strips around the wires or bead rings. The ■ drive according to the invention essentially comprises the steps! that there is at least one inner drum around the above-mentioned drum Layer of rubber wrapped around at least two of the above; imagined that they had strips to reinforce the bulges:

brings which are arranged at opposite ends of the drum \ respectively to gen laterally beyond the latter hervorzusprin- _(and that at least one carcass layer on both sides. protrudes th Furthermore, the process consists in that at least two bead rings respectively at the opposite ends of the drum and at least each carcass ply and strip around the bead rings is folded back radially outward onto the outside. Furthermore, at least one outer rubber layer is wound onto the drum. The invention thus produces an improved pneumatic tire that is reliable and effective as above described disadvantages of: eliminates pneumatic tires, which were manufactured according to the previous methods, while at the same time the manufacture of the new tire is very simple and economical.

The invention is explained below with reference to schematic drawings

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explained in more detail using several exemplary embodiments.

Fig. 1 shows a cross section in a radial plane of a pneumatic tire according to the invention.

I Fig. 2 is a partial cross-section, similar to that of Fig. 1,

and shows another embodiment of the new! Tire. '

Fig. 3 is a half cross-section, similar to that of Fig. 2, j and shows a further embodiment, while

Fig. 4 in turn shows a further embodiment in the same Representation as Fig. 2 shows.

Referring to Fig. 1, there is a radial ply tire according to the invention of at least one carcass layer made of a rubber covered fabric with radial cord elements 1 extending continuously extend from one bead 2 to the other bead 2a and in the area of each bead to the outside by in each case a bead ring 3 or 3a are turned over. Each bead ring has a cover or apex 4,4a. The arrangement

tion is made in such a way that every outwardly folded outer! Section la baw. Ib over a certain height over the associated | rigen bead ring rises outwards and upwards. ;

At least one strip 5 or 5a of woven material serving to reinforce the bead is applied to each bead area applied that it surrounds each corresponding bead ring 3 or 3a by moving to the outside of the corresponding to-

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The folded-back or turned-back part of the carcass ply 1 is covered. That means that this part is included and is covered by the protective strip from the inner surface of the carcass ply to the outer surface and is wrapped around the bead ring in the direction of the outside. The two folded back sections of the carcass ply 1 in each bead area are thus completely in the concave curvature of each reinforcing strip 5.5a added.

The tire comprises a substantially circumferential reinforcing belt 6 extending on the outside of the carcass ply 1 and consists for example of two superimposed layers of cord fabric covered with rubber. The cord elements may be made of metal cord and are parallel in each layer in a substantially circumferential direction of the tire arranged. These reinforcement belts are marked with j

a tread rubber layer 7 and layers 8,9 of rubber covered, which cover the carcasses on the outside and inside i. Layers 8 and 9 are essentially in the Arranged side areas of the tire and at the same time serve to cover the bead areas.

In a radial cross-sectional plane, as shown in Fig. 1, the areas 5c and 5e of the sections 5b and 5d the bead reinforcement strip 5.5a different lengths. The axially inner sections 5b and 5d of the strips 5, 5a

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are preferably longer than the axially outer sections 5c and 5e. Sections 5c and 5e are longer than the outermost folded back outer portions la, Ib of the carcass ply 1. If H is the distance to the extreme end of the longest section 5b, 5d of each strip 5,5a up to the determined radially inner end of the associated bead area 2.2a, the respective distances are up to the radial inner end of the bead portions 2,2a, measured from the outer ends of the shortest area 5c, 5e of the strips 5,5a and j from the extreme ends of the outer folded back portions la, Ib of the carcass ply 1 approximately approximately half (H / 2) or approximately 1/3 (H / 3) of the distance H from the extreme end of the longest section 5b, 5d of each strip 5.5a to the radially inner end of the corresponding bead 2.2a. The end of the longest folded over portion 5b, 5d of each reinforcement strip 5.5a lies between the corresponding bead and half the height H of a radial cross section of the tire. The minimum length of the longest folded section 5b, 5d should extend to a point which is at least 1/4 the height of a radial cross-section of the reed fens over the radially inner end of the corresponding bead! extends.

In Fig. 1 and the other embodiments of the tire according to the invention, when the end of the longest folded portion of each reinforcement strip extends over the mean height of a radial cross-section of the tire

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extends, separation of the ply ends or carcass ply cutting in the tire sidewall occurs. In contrast, with the length ratios of H, H / 2 and H / 3 »as explained above and in the following in connection with the; other embodiments are explained in more detail, neither an edge separation of the carcass layers nor a groove formation! bulging or cutting occur between the turned-up edges and the carcass layers.

Fig. 2 shows a modification of the pneumatic tire according to Fig.l again, with the corresponding parts with the same! Reference numerals are denoted. Accordingly, in a radial, Cross-sectional plane, as shown in Fig. 2, of:

axially outer area 5c of each reinforcement strip 5 longer than the axially inner portion 5b, which in turn is longer is as the extreme end of the folded-back outer portion la of each carcass ply 1. Here, the respective Distances between the outer end of the shortest or inner region 5b of the reinforcement strip and the outer end of the folded back outer portion la of the carcass ply, based on the radially inner end of the associated Bead, at least approximately half or 1/3 of the distance from the outermost end of the longer or outer section 5c of the strip 5

In the further embodiment according to FIG. 3, the extremely folded back outer portion 1b of each carcass ply is 1

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shorter than the axially inner region 5d of each bead strip 5a, but longer than the axially outer region 5e of this reinforcing strip. . After embodiment of Figure ¹ I is the extreme fold-back outer portion of the carcass Ib · j layer 1 is shorter than the axially outer portion 5e of each Wulstverstärkungsstreifens 5a ", however longer than the axially inner; Part 5d of this reinforcement strip. In the latter
In both cases, the respective distances from the outer, end of the outermost folded back section Ib of each casing layer 1 and the shortest part 5e or 5d of the cover are ^:

Strengthening strip 5a, based on the radially inner end of the I.

corresponding bead 2a, each approximately 1/2 or 1/3, of the distance from the outermost end of the longest section
5d or 5e of the reinforcement strip. j

The embodiment shown in Fig. 3 can be used in the case of a small pneumatic tire. It is
particularly advantageous in this case, since in this case more \ fabric is eingesaprt that each Wulstver-> reinforcing strips 5a is not so far up as a result, protrudes with its outer umgefalr j depressed area 5e.

It can be seen that the in ^{FIGS. 2, 3 and 1} I are not shown; placed cross-section halves in relation to the cross-sections that; are shown in Figs. ^2, 3 and 11, are formed similarly. ; It should also be noted that in Figs. 2,3 and ^
just as in the embodiment of FIG. 1, the ends

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of the longest folded portion of each reinforcement strip between the corresponding bead and half the height of a radial cross section of the tire. The minimum length of the longest folded section of each reinforcement strip should not be less than IM the height of a radial Be the cross-section of the tire.

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Claims (8)

Claims 1. Radial layer tire for vehicles, consisting of a / Carcass with at least one layer of reinforcing material, the elements of which are essentially radial Direction from at least one reinforcement ring of one tire bead to at least one reinforcement ring of the other Tire beads run and which has edge portions that are placed around the reinforcement rings to the outside and at least one reinforcement strip of woven material for each bead, each having a section which, based on the reinforcement ring, is wrapped around the associated bead ring outside the carcass ply, characterized in that; that the folded-over portion of the or each reinforcing strip (5) is longer than the folded-back portion (la, Ib) of the carcass ply (1) and that the end of the longest of the folded portions (5b, 5d) of the or each Reinforcement strip between the associated bead (2.2a) and the center height (H) of the radial cross-sectional height of the Tire lies. 2. Radial layer tire according to claim 1, characterized in that in a radial cross section of the tire is the distance of the radially inward edge of each bead from the end of one of the shortest folded over Sections (5c, 5e) of the associated reinforcement 309831/0347 Strip (5) and the associated turned-back portion (la, Ib) of the carcass layer (1) approximately Half of the distance to the radially inner edge of the bead (2.2a) from the end of the corresponding longest folded Section of the reinforcing strip is and that the distance to the radially inner edge of the bead from End of the other of the shortest folded sections of the corresponding reinforcement strip and the corresponding turned-back portion of the carcass ply approximately 1/3 of the distance to the radially inner Edge of the bead from the end of the corresponding longest folded portion of the associated reinforcement strip amounts to. 3. Pneumatic tire according to one of claims 1 or 2, characterized in that the longest folded portion of each reinforcement strip axially within the carcass ply and the shortest folded The portion of each reinforcement strip lies axially outside the carcass ply and is longer than that which is folded back Section of the carcass ply (Fig. 1). 4. Radial ply tire according to any one of claims 1 or 1 2, characterized in that the longest folded portion of each reinforcement strip axially outside the carcass ply and the shortest folded portion of each reinforcement strip axially inside 309831/0347 half of the carcass ply and is longer than the folded back Section of the carcass ply (Fig. 2). 5. Radial layer tire according to one of claims 1 or 2, characterized in that the longest folded portion of each reinforcement strip axially within the carcass ply and the shortest folded Portion of each reinforcement strip is axially outside the carcass ply and is shorter than that corresponding turned-up portion of the carcass ply (Fig. 3) A radial ply tire according to claim 1 or 2, characterized in that the longest folded portion of each reinforcement strip extends axially outside the carcass ply and the shortest folded portion of each reinforcement strip extends axially within the carcass ply and is shorter than the corresponding turned-back portion of the carcass ply (Fig. 4). 7. Radial layer tire according to any one of the preceding claims, characterized in that that the end of the longest folded portion of each reinforcement strip extends to a point which at least 1/4 of the height (H) of the radial cross-section of the tire above the radially inner edge of the associated 309811/0347 rigen bead lies. 8. Radial layer tire according to any one of the preceding claims, characterized in that that each reinforcement strip is made of a woven material with regularly interwoven warp and weft threads. 3098 ^ 1/0347 Blank page