GB2108440A

GB2108440A - Tyre crown reinforcements

Info

Publication number: GB2108440A
Application number: GB08225349A
Authority: GB
Inventors: Heinrich Huinink
Original assignee: Continental Gummi Werke AG
Current assignee: Continental AG
Priority date: 1981-09-19
Filing date: 1982-09-06
Publication date: 1983-05-18
Also published as: IT8222893V0; FR2513187A1; DE3137329A1; FR2513187B1; IT8223305A0; JPS5861005A; IT1152606B

Abstract

A pneumatic vehicle tyre has a crow-reinforcing belt comprised of two cross-laid cord plies (7, 8), and cord fabric strips (11, 12) arranged closely above and below the ply edges. The cords (14) of each strip are inclined to the circumferential direction of the tyre so as to cross the cords (9) of the adjacent ply (7, 8), with the cords (14) of one strip (11) crossing those of the other strip (12). The cords of the plies (7, 8) may be of steel and those of the strips (11, 12) of heat-shrinkable textile. Angle b may be less than angle a, and ply (7) may be wider than ply (8). <IMAGE>

Description

SPECIFICATION Pneumatic vehicle tyre The present invention relates to a pneumatic vehicle tyre having an inextensible belt which extends substantially over the width of the thread strip and is disposed between the caracase and tread strip, the belt having two belt plies which are preferably made of steel and have reinforcing members arranged in the cord ply, wherein the reinforcing members extend parallel to one another in each belt ply, but the reinforcing members of one belt ply intersect the reinforcing members of the other belt ply, strips being arranged closely above and below the belt edges and being made of cord fabric, and the reinforcing members of each of said strips extending diagonally to the circumferential direction of the tyre.

Pneumatic tyres of this construction are already known, in which the reinforcing members of the laterally disposed cord fabric strips are arranged parallel to one another and the surrounding edges of the belt form a "U" shape. The so-cailed cut edges of the belt plies are actually covered thereby, but no stable transition is produced between the belt plies, which are made of steel, and the shouider of the tyre.

To eliminate these disadvantages, according to the invention, it is proposed that the reinforcing members of each strip form a preferably symmetrical cross binding with the reinforcing members of the two belt plies, and that the reinforcing members of one strip form a preferably symmetrical cross binding with the reinforcing members of the other strip.

This produces not only a desirable diamondshaped binding between the strips and the edges of the belt plies, but the reinforcing members of the two strips are extended so far laterally over the edges of the belt plies that, in turn, they can form a cross binding with one another, i.e. both strips can form a cross binding with one another. If these strips are formed from textile filaments, e.g. from polyester or polyamide filaments, a favourable transition is produced in the region of the belt edges; this eliminates the possibility of parting occurring at the belt edges.

The present invention will be further illustrated, by way of example, with reference to the accompanying drawings in which: Figure I is a radial, partially sectional, view through a pneumatic vehicle tyre; and Figure 2 is a partial plan view of a belt for the tyre shown in Figure 1.

The substantially horsehoc-shaped tyre body is strengthed by a carcase 1, and the inextensible reinforcing members 2 of the carcase 1 extend along the shortest path between one bead 3 and the other bead 3, i.e. they are arranged in a radial manner. The ends of the reinforcing members 2 are secured in the beads 3 by looping-round the bead cores 4.

The belt 5 is located in the crown portion of the tyre between the tread strip 6 and the part of the carcase 1 located on the outer periphery of the tyre.

When viewed in the circumferential direction of the tyre, the belt 5 is inextensible in conventional manner. It strengthens the tread strip zone and stabilises the tyre body 1 by the action of lateral forces.

All the filament-shaped reinforcing plies of the belt 5 are inextensible; they are arranged in cord ply and are vulcanised into the rubber covering.

The belt 5 comprises an upper belt ply 7 and a lower belt ply 8. Both belt plies 7 and 8 are formed from steel cables or wires 9. At both edges in the shoulder zones 10, the upper belt ply 7 projects beyond the lower belt ply 8 by approximately 5% to 15% of its width.

Two strips, namely an upper strip 11 and a lower strip 12, are located in the region of both belt edges.

However, in contrast to the two belt plies 7 and 8, these strips 11 and 12, likewise made of cord fabric, are formed from heat-shrinkable textile material, for example, polyamide or polyester. The strips 11 and 12 overlap the edges of the adjacent belt plies 7 and 8 but, in turn, they are laterally externally brought close together orjoined at 13. In such a case, the overlapping width portion of the strips 11 and 12 essentialy corresponds to the width region located laterally externally beside the lateral edges of the belt plies 7 and 8.

The belt plies 7 and 8 have intersecting reinforcing members 9. The reinforcing members 9 of the belt ply 7 extend upwardly to the right and the reinforcing members 9 of the belt ply 8 extend upwardly to the left so that identical angles a of approximately 18 to 250 are formed with the circumferential direction of the tyre. It is also important, however, for the reinforcing members 14 of the strips 11 and 12 to intersect one another, thereby forming with the circumferential direction of the tyre angles b which, however, are a few degrees smaller, e.g. 3 to 80 smaller, than the angles a, so that the angles b may, in consequence, be approximately 80 to 15".

The reinforcing members 14 of the upper strip 11 extend upwardly to the left, i.e. they cross the reinforcing members 9 of the belt ply 7, whereas the reinforcing members 14 of the strips 12 cross the reinforcing members 14 of the strips 12 cross the reinforcing members 9 of the belt ply 8 and, in addition, because they extend upwardly to the right, they are arranged so that the reinforcing members 14 of the two strips 11 and 12 form a symmetrical cross binding with one another.

As Figure 1 indicates, the strips 11 may also be slightly laterally externally offset relative to the strips 12. This offset arrangement, which is not shown in Figure 2, may correspond to the width of the edge transition sat the two edges of the belt plies 7 and 8.

1. A pneumatic vehicle tyre having an inextensible belt which extends substantially over the width of the tread strip and is disposed between the carcase and tread strip, the belt having two belt plies which have reinforcing members arranged in the cord ply, wherein the reinforcing members extend parallel to one another in each belt ply, but the reinforcing members of one belt ply intersect the reinforcing members of the other belt ply, strips

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Pneumatic vehicle tyre The present invention relates to a pneumatic vehicle tyre having an inextensible belt which extends substantially over the width of the thread strip and is disposed between the caracase and tread strip, the belt having two belt plies which are preferably made of steel and have reinforcing members arranged in the cord ply, wherein the reinforcing members extend parallel to one another in each belt ply, but the reinforcing members of one belt ply intersect the reinforcing members of the other belt ply, strips being arranged closely above and below the belt edges and being made of cord fabric, and the reinforcing members of each of said strips extending diagonally to the circumferential direction of the tyre. Pneumatic tyres of this construction are already known, in which the reinforcing members of the laterally disposed cord fabric strips are arranged parallel to one another and the surrounding edges of the belt form a "U" shape. The so-cailed cut edges of the belt plies are actually covered thereby, but no stable transition is produced between the belt plies, which are made of steel, and the shouider of the tyre. To eliminate these disadvantages, according to the invention, it is proposed that the reinforcing members of each strip form a preferably symmetrical cross binding with the reinforcing members of the two belt plies, and that the reinforcing members of one strip form a preferably symmetrical cross binding with the reinforcing members of the other strip. This produces not only a desirable diamondshaped binding between the strips and the edges of the belt plies, but the reinforcing members of the two strips are extended so far laterally over the edges of the belt plies that, in turn, they can form a cross binding with one another, i.e. both strips can form a cross binding with one another. If these strips are formed from textile filaments, e.g. from polyester or polyamide filaments, a favourable transition is produced in the region of the belt edges; this eliminates the possibility of parting occurring at the belt edges. The present invention will be further illustrated, by way of example, with reference to the accompanying drawings in which: Figure I is a radial, partially sectional, view through a pneumatic vehicle tyre; and Figure 2 is a partial plan view of a belt for the tyre shown in Figure 1. The substantially horsehoc-shaped tyre body is strengthed by a carcase 1, and the inextensible reinforcing members 2 of the carcase 1 extend along the shortest path between one bead 3 and the other bead 3, i.e. they are arranged in a radial manner. The ends of the reinforcing members 2 are secured in the beads 3 by looping-round the bead cores 4. The belt 5 is located in the crown portion of the tyre between the tread strip 6 and the part of the carcase 1 located on the outer periphery of the tyre. When viewed in the circumferential direction of the tyre, the belt 5 is inextensible in conventional manner. It strengthens the tread strip zone and stabilises the tyre body 1 by the action of lateral forces. All the filament-shaped reinforcing plies of the belt 5 are inextensible; they are arranged in cord ply and are vulcanised into the rubber covering. The belt 5 comprises an upper belt ply 7 and a lower belt ply 8. Both belt plies 7 and 8 are formed from steel cables or wires 9. At both edges in the shoulder zones 10, the upper belt ply 7 projects beyond the lower belt ply 8 by approximately 5% to 15% of its width. Two strips, namely an upper strip 11 and a lower strip 12, are located in the region of both belt edges. However, in contrast to the two belt plies 7 and 8, these strips 11 and 12, likewise made of cord fabric, are formed from heat-shrinkable textile material, for example, polyamide or polyester. The strips 11 and 12 overlap the edges of the adjacent belt plies 7 and 8 but, in turn, they are laterally externally brought close together orjoined at 13. In such a case, the overlapping width portion of the strips 11 and 12 essentialy corresponds to the width region located laterally externally beside the lateral edges of the belt plies 7 and 8. The belt plies 7 and 8 have intersecting reinforcing members 9. The reinforcing members 9 of the belt ply 7 extend upwardly to the right and the reinforcing members 9 of the belt ply 8 extend upwardly to the left so that identical angles a of approximately 18 to 250 are formed with the circumferential direction of the tyre. It is also important, however, for the reinforcing members 14 of the strips 11 and 12 to intersect one another, thereby forming with the circumferential direction of the tyre angles b which, however, are a few degrees smaller, e.g. 3 to 80 smaller, than the angles a, so that the angles b may, in consequence, be approximately 80 to 15". The reinforcing members 14 of the upper strip 11 extend upwardly to the left, i.e. they cross the reinforcing members 9 of the belt ply 7, whereas the reinforcing members 14 of the strips 12 cross the reinforcing members 14 of the strips 12 cross the reinforcing members 9 of the belt ply 8 and, in addition, because they extend upwardly to the right, they are arranged so that the reinforcing members 14 of the two strips 11 and 12 form a symmetrical cross binding with one another. As Figure 1 indicates, the strips 11 may also be slightly laterally externally offset relative to the strips 12. This offset arrangement, which is not shown in Figure 2, may correspond to the width of the edge transition sat the two edges of the belt plies 7 and 8. CLAIMS

1. A pneumatic vehicle tyre having an inextensible belt which extends substantially over the width of the tread strip and is disposed between the carcase and tread strip, the belt having two belt plies which have reinforcing members arranged in the cord ply, wherein the reinforcing members extend parallel to one another in each belt ply, but the reinforcing members of one belt ply intersect the reinforcing members of the other belt ply, strips being arranged closely above and below the belt edges and being made of cord fabric, and the reinforcing members of each of said strips extending diagonally to the circumferential direction of the tyre, the width of said reinforcing members corresponding approximately to 15% to 25% of the width of the actual belt, in which the reinforcing members of each strip form a cross binding with the reinforcing members of the two belt plies and the reinforcing members of one strip form a cross binding with the reinforcing members of the other strip.

2. A tyre as claimed in claim 1 in which the reinforcing members of each strip form a symmetrical cross binding with the reinforcing members of the two belt plies and the reinforcing members of one strip form a symmetrical cross binding with the reinforcing members of the other strip.

3. Atyre as claimed in claim 1 or 2, in which the angles subtended by the reinforcing members of the two strips with the circumferential direction of the tyre are slightly smaller (approximately 3" to 8" smaller) than the angles subtended by the two belt plies with the circumferential direction of the tyre.

4. A tyre as claimed in claim 1,2 or 3, in which the reinforcing members of the two belt plies are made of steel or a similar strength inextensible material, whereas the reinforcing members of the two strips are made of a heat-shrinkable textile material.

5. Atyre as claimed in any one of claims 1 to 4, in which the upper belt ply protrudes at both edges beyond the lower belt ply by approximately 5% to 15% of its width.

6. A tyre as claimed in claim 5, in which the strips located on the outer periphery of the tyre protrude laterally externally beyond the lower strips, and such lateral offsetting corresponds substantially to the offsetting of the two belt plies.

7. Atyre as claimed in any preceding claim in which the strips lie closely together laterally externally beside the edges of the two belt plies.

8. A pneumatic tyre, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.