JPH03143704A - Pneumatic radial tire - Google Patents

Abstract

PURPOSE:To prevent vibration at the time of running with uniformity of a tire improved by winding a belt-shaped unit, in which a plurality of reinforcing element are coated with a coating member consisting of high molecular material of low elastic modulus, helically by a plural number of times in the peripheral direction to form a reinforcing layer. CONSTITUTION:A tire is provided with a toroidal carcass layer 2 simultaneously with a reinforcing layer 15, having a width narrower than a belt layer 6, provided in a radial direction outside the carcass layer 2. Here the reinforcing layer 15 is formed of two layers of reinforcing plies 16. While each reinforcing ply 16 is formed such that a long and thin belt-shaped unit 17 is wound helically by a plural number of times in the peripheral direction. Further the belt-shaped unit 17 is formed of a plurality of reinforcing elements 18, separated with an equal distance, and coating members 19 for coating these reinforcing elements. The adjacent belt-shaped units 17 are connected by the fellow side ends of this unit 17, thus by uniformly distributing connection parts in the peripheral direction, vibration at the time of running is prevented while improving uniformity of the tire.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pneumatic radial tire in which a belt layer and a reinforcing layer are arranged radially outside a toroidal carcass layer.

Conventionally, a pneumatic radial tire that is easy to vulcanize and mold and has good tire durability during high-speed running is a toroidal carcass layer in which many cords extending in the radial direction are buried. a belt layer disposed radially outward of the carcass layer; and a reinforcing layer disposed radially outward of the carcass layer and overlapping with the belt layer,
The reinforcing layer is wrapped once (2
In the case of a layer, it is known to be constructed by winding the band only twice) and by overlapping and joining the longitudinal end and the longitudinal end of each band.

However, in such pneumatic radial tires, the joints of the reinforcing layers are unevenly distributed in one place (two places in the case of two layers) on the circumference, and moreover, these joints are overlapped. Since the tires are thick due to bonding, there is a problem in that the uniformity of the tires deteriorates and vibrations may occur during driving.

An object of the present invention is to provide a pneumatic radial tire with good uniformity despite having a reinforcing layer.

This purpose is to create a toroidal carcass layer in which a large number of cords extending in the radial direction are embedded, a belt layer placed radially outside the carcass layer, and a belt layer placed radially outside the carcass layer. A pneumatic radial tire comprising a reinforcing layer overlapping the belt layer, wherein the reinforcing layer is made of a polymeric material with a low elastic modulus, and the reinforcing element is of the same phase and is curved in a wavy or zigzag shape. This can be achieved by winding a band-shaped body covered with a covering member consisting of the following in the circumferential direction in a twisted spiral.

As described above, the reinforcing layer of the present invention is constructed by winding a band-shaped body in which a plurality of reinforcing elements in the same phase are covered with a covering member in a spiral shape a plurality of times in the circumferential direction. As a result, adjacent strips are joined at their side edges, but since these joints are evenly distributed in the circumferential direction, the uniformity of the tire is good and vibrations are prevented when driving. You can also do that.

Furthermore, with the configuration as set forth in claim 2, the side ends of the band-like bodies can be butt-joined to each other, so that the uniformity of the tire can be dramatically improved.

Furthermore, if the structure is configured as described in claim 3, the reinforcing layer can be easily molded, and work efficiency can be improved.

Moreover, if configured as described in claim 4, the reinforcing layer can be formed by two layers.
Even when the reinforcing ply is made up of more than one layer, it can be molded easily and with high efficiency.

Practical JL Example Hereinafter, a first embodiment of the present invention will be described based on the drawings.

In Fig. 1.2.3, 1 is a pneumatic radial tire, and this tire 1 has a toroidal-shaped carcass layer 2, and this carcass layer 2 has a large number of coats 3 extending in the radial direction inside. It is composed of at least one (one in this embodiment) carcass ply 4 buried therein.

A belt layer 6 is disposed on the radially outer side of the carcass layer 2, and a trend 8 in which a plurality of main grooves 7, etc. are formed is disposed on the radially outer side of the belt layer 8. The belt layer 6 is composed of at least one belt ply, in this embodiment two belt plies ll, each belt ply 11 having a belt ply in the opposite direction at an angle of 10 degrees to 40 degrees with respect to the tire equatorial plane 12. A large number of reinforcing cords made of non-stretchable material, for example steel, are embedded in the structure. A reinforcing layer 15 having a width slightly narrower than that of the belt layer 6 is disposed on the outside of the carcass layer 2 in the radial direction. It overlaps layer 6 over almost the entire width.

The reinforcing layer 15 is composed of at least one layer of reinforcing ply, in this embodiment two layers of reinforcing ply 16. Each reinforcing ply 1e is constructed by winding an elongated strip 17 in a spiral shape multiple times in the circumferential direction. In this embodiment, the reinforcing ply 1e is continuously wound from one end in the width direction of the belt layer 6 to the other end in the width direction. By doing this, the reinforcing ply 1G on the inner layer side is formed, and then, by continuously winding the belt layer 8 from the other end in the width direction to one end in the width direction, the reinforcing ply IG on the outer layer side is formed. When the reinforcing layer 15 is composed of the strips 17 wound spirally in this way, the adjacent strips 17 are joined at their side ends, so that the joints are uniformly distributed in the circumferential direction. As a result, the uniformity of the tire 1 is improved, and vibrations during driving can be prevented. The band-like body 17 includes a plurality of reinforcing elements 18 spaced apart from each other at equal distances, and these reinforcing elements! 8, and a covering member 19 that covers 8. Here, each reinforcing element is composed of a cord (stranded wire) or a single filament, and is made of a non-stretchable material such as steel, Kevlar (aromatic polyamide), etc. In addition, these reinforcing elements may have a wavy or zigzag shape in a plane parallel to the front and back surfaces of the covering member 19, for example, a square wave, a triangular wave,
They are bent in a sinusoidal manner, and all are arranged in the same phase. In this embodiment, the wavelength a of the reinforcing element 18 is set to an integral fraction of the outer circumferential length of the carcass layer 2. As a result, the reinforcing element 1 of the strip 17 at a certain winding position
8 and the reinforcing element 18 of the strip 17 adjacent to the strip 17
When the positions in the circumferential direction are the same, the phases are the same as shown in FIG. The covering member 19 is a reinforcing element 18
It is made of a polymeric material with a lower modulus of elasticity, such as rubber or epoxy resin. Further, both ends of this covering member 19 (both ends in the width direction) are connected to both outermost reinforcing elements +8a, 18.
b (reinforcing elements at both ends) protrudes outward by approximately 1/2 of the distance d between the reinforcing elements 18 to form a pair of ears 20. As a result, the width of the covering member 19 is approximately equal to the distance f between the outermost reinforcing elements 18a and +8b.
The reinforcing element 18 has a constant width S plus a spacing d between 8 and 8, and is bent in a wavy or zigzag manner along the reinforcing element 18 as a whole. Then, this strip-shaped body 17 is wound spirally while the outer ends of the ears 20 are abutted against each other, and the adjacent strip-shaped bodies 17 are abutted and joined.

Here, since the above-mentioned band-shaped body 17 is difficult to mold and also difficult to wind, it is also conceivable to make it as shown in FIG. 4.5. That is, the covering member 21 is made to extend linearly regardless of the bending of the reinforcing element 18, and its @C is connected to the peak 22 of the reinforcing element +8a located at one end.
The distance me from 1 to the valley 23 of the reinforcing element 18b located at the other end is set to a constant width, and the distance d between the dowel reinforcing elements 18 is added. By winding the strips 24 spirally, adjacent strips 24 are butted and joined together. However, in this case, the reinforcing element 18b located at the other end of each strip 24 and the strip 2 adjacent to the strip 24
4 and the reinforcing element 18a located at one side end of the reinforcing element 1.
A soft region g, in which the reinforcing element 18 is not driven, is generated, which bends in the same phase as the reinforcing ply 8, or whose width changes periodically depending on the circumferential position. The reinforcing layer 15 exists in a spiral shape within the
This results in a decrease in rigidity. In order to prevent such a decrease in rigidity, one more layer of reinforcing ply 18 may be wrapped, but if this is done, the thickness of reinforcing layer 15 becomes too thick and the durability of tire 1 decreases. It's put away.

On the other hand, as in the first embodiment described above, the reinforcing element 1
The wavelength a of 8 is set to an integer fraction of the outer circumference length of the carcass layer 2, and the distance d is approximately 1 at both ends of the covering member 18.
By forming ears 2o with a width of /2 and joining adjacent strips 17 by abutting the outer ends of these ears 20, the reinforcing elements 18 in each reinforcing braai 16 can be fixed to each other. Since the strips 17 forming each reinforcing ply 1B are butt-jointed, there may be no occurrence of the region g as described above since they are arranged apart from each other by the distance d. do not have. This makes it possible to dramatically improve the uniformity of the tire.

FIG. 6.7 shows a second embodiment of the invention. In this embodiment, the strip shown in FIG. 4.5 above,
That is, while extending the covering member 2 in a straight line, its @C is defined as the distance # from the peak 22 of the reinforcing element 18a located at one end to the valley 23 of the reinforcing element 18b located at the other end.
The belt-like body 24 has a constant width equal to e and the distance d between the dowel reinforcing elements 18. And in this example,
The reinforcing ply 16 is constructed by overlapping the side ends of such strips 24 by an amount approximately equal to the amplitude of the reinforcing element I8 and winding them in a spiral shape, so that adjacent strips 24 are overlapped and joined together. I have to. As a result, each strip 2
4, and a reinforcing element 18a located at one end of the strip 24 adjacent to the strip 24.
The region g as described above does not occur between the reinforcing layer 1
It is possible to improve the rigidity of No. 5.

Here, the reinforcing element 1 of the strip 24 at a certain winding position
8 and the reinforcing element 1 of the strip 24 adjacent to this strip 24
8 is normally different in phase as shown in FIG. Since the number of reinforcing plies 16 is substantially constant at any position, the strength of the reinforcing ply 16 does not change depending on the position in the width direction. In addition, when the width C of the covering member 21 is a value obtained by adding the distance d to the distance me, the side ends of the band-shaped body 24 are overlapped by an amount equal to the vibration @ h of the reinforcing element 18 in a spiral shape. The width C of the band-shaped body 24 is the distance
If the width is slightly wider or narrower than the sum of the width and the distance d, the amount of overlap is adjusted by increasing or decreasing the amplitude of the reinforcing element 18. In this embodiment, it is easy to form the band-shaped body 24 as described above, and furthermore,
Since the band-like body 24 can be easily wound, the reinforcing layer 15 can be formed easily and with high efficiency. In the present invention, the wavelength of the reinforcing element I8 may be set to be an integral fraction of the outer circumferential length of the carcass layer 2, as in the first embodiment.

Here, when the reinforcing layer 15 is formed from one reinforcing ply IG, the above explanation may be followed, but when the reinforcing layer 15 is formed from two reinforcing plies 1B, as shown in FIG. Then, the strip 24 is wound spirally on the outside of the inner reinforcing ply 16 while overlapping the side ends of the strip 24 by an amount approximately equal to the amplitude of the reinforcing element 18.
Molding the outer reinforcing ply 16. At this time, in order to prevent air from remaining between the inner reinforcing ply 16 and the outer reinforcing ply 16, it is necessary to It is necessary to wind the belt-shaped body 24 while ensuring that the other end of the belt-like body 24 is abutting against the other end, which makes the winding work troublesome. For this reason, in the second embodiment, the reinforcing layer 15 is composed of one reinforcing ply 16.
This is effective when the reinforcing ply 16 is composed of two or more layers, but the workability deteriorates and is disadvantageous when the reinforcing ply 16 is composed of two or more layers.

FIG. 9 is a diagram showing a third embodiment of the present invention. In this embodiment, when the reinforcing layer 15 is composed of two or more layers of reinforcing ply 16, the reinforcing layer 15 can be molded with high efficiency. It is possible. In this embodiment, the covering member 31
extends in a straight line. Further, from the peak 22 of reinforcing element +8a located at one end, to the reinforcing element 1 located at the other end.
The distance #e to the valley 23 of 8b is the distance (AX h
), and a constant value obtained by adding approximately the distance d between the reinforcing elements 18 to this distance #e (AXh) is set to the covering member 3.
The width C is 1. In this embodiment, the band 32 as described above is multiplied by the amplitude of the reinforcing element 18 by an integer B (in this case, 3) that is 2 or more, more than 172 times the integer A, and less than 1. By spirally winding the strips 32 while overlapping each other by approximately the same amount, the reinforcing layer 15 is constructed by overlapping and bonding adjacent strips 32 to each other. As a result, the molded reinforcing layer 1
The region g as described above does not occur within the reinforcing layer 15.
Improves rigidity. Moreover, the reinforcing layer 15 formed in this manner has a plurality of reinforcing elements 18, in this case two stages, overlapping each other, and the result is similar to the case where two reinforcing plies are overlapped. Note that this example and the second
In any of the embodiments, there is only one reinforcing element 18 at both ends in the width direction of the reinforcing layer 15, that is, at the beginning and end of the winding of the strip 24.32;
does not exist at all. Also, in this example,
The reinforcing element 18 of the strip 32 at a certain winding position and the reinforcing element 1B of the strip 32 adjacent to this strip 32 are:
Normally, the phases are different as in the second embodiment, but even if the phases are different, the number of reinforcing elements 18 implanted within a unit width is almost the same at any position. Since the strength is constant, the strength of the reinforcing layer 15 does not change depending on the position in the width direction. Furthermore, in this embodiment as well, if the width C of the strip 32 is the sum of the distance #e and the distance d, the width of the strip 32 is increased by the amplitude of the reinforcing element 18 by an integer B (3 in this case). It is sufficient to wind it spirally while overlapping by the exact amount multiplied by the amount, but if the width C of the strip 32 is slightly wider or narrower than the sum of the distance iae and the distance d, the overlapping amount is adjusted by slightly increasing or decreasing the above value. Furthermore, when the integer A is 3 and the integer B is 2, it is possible to construct a reinforcing layer similar to when M layers of two reinforcing plies are formed. In this case, a reinforcing layer similar to that obtained by laminating three reinforcing plies can be constructed.

In addition, in the above embodiment, the reinforcing layer 15 is arranged to overlap almost the entire width of the belt layer θ, but in the present invention, it may be arranged to overlap only at both ends of the belt layer 6 in the width direction. . Further, in the above-mentioned embodiment, the width of the reinforcing layer 150 was made slightly narrower than the width of the belt layer 6, but in the present invention, the width of the reinforcing layer 150 is set to be the same width as the belt layer 6, or slightly wider than the belt layer 8 for reinforcement. Both ends of the layer 15 in the width direction may protrude outward from the belt layer 6. Here, even when the reinforcing layer is disposed only at both ends of the belt layer 8 in the width direction as described above, the reinforcing layer The outer end in the width direction may be made to protrude outward from the belt layer e. Furthermore, in the above-mentioned embodiment, the reinforcing layer 15 is
In the present invention, two reinforcing layers may be arranged between the belt layer 6 and the tread 8, and the belt ply 11 constituting the belt layer 6 may be
It may be placed in between.

Next, a test example will be explained. In this test, two strips of the same width as the total width of the reinforcing layer (185ml11) were placed in the circumferential direction.
A comparative tire having a reinforcing layer formed by winding the strips together and overlapping and bonding the longitudinal ends and the longitudinal ends of each strip, and the strip 24 having a width of 20.8 mm as shown in FIG. A reinforcing ply was formed by winding the reinforcing ply 8 times in a spiral shape while butt-joining the reinforcing ply. As shown in Figure 2.3, a reinforcing ply was formed by winding the strip 8 times in a spiral shape while butt-joining it, and a reinforcing layer was constructed by laminating two layers of such reinforcing ply. A reinforcing ply is formed by winding the tire 2 and a linear strip having a width of 25 mm eight times in a spiral shape while overlapping their side ends as shown in FIG.
A test tire 3 having a reinforcing layer formed by laminating two layers of such reinforcing ply and a linear strip having a width of 25 mm were stacked one on top of the other in a spiral shape as shown in FIG.
A test tire 4 having a reinforcing layer formed by winding it five times,
of? I did s@. Here, the structure of each tire described above is the same as tire 1 described in FIG. 1 except for the reinforcing layer.
The size of both is 11/70R22.5.

In addition, the reinforcing elements of each tire are 3+ 9+ 15x O,
15 steel cord with an amplitude of 5 mm and a wavelength a of 53
．． The reinforcement elements are bent along a 7mm sine wave, and such reinforcing elements are embedded at equal intervals of 8 pieces in the strip of each test tire, while in the reinforcing braai of the comparison tire. 64 trees are buried at equal intervals. Next, each tire was filled with an internal pressure of 7.5 kg/cm' and was driven at a speed of 3 km/h while applying a load of 2400 kg.
The tire was run on a test drum, and the longitudinal force fluctuation (RFV) generated in each tire at this time was measured. As a result, the weight of the comparison tire was 145 kg, but it decreased to 82 kg for test tire 1, 68 kg for test tire 2, 80 kg for test tire 3, and 75 kg for test tire 4. It can be seen that applying this invention will definitely improve uniformity.

As explained above, according to the present invention, uniformity is improved and vibrations do not occur during running.

[Brief explanation of the drawing]

FIG. 1 is a meridian cross-sectional view showing a first embodiment of the present invention, FIG. 2 is a developed view of the vicinity of the reinforcing layer, and FIG. 3 is an I--
4 is a developed view of a reinforcing braai constructed by butt-joining the side ends of linearly extending strips; FIG. 5 is a sectional view taken along the ■-■ arrow in FIG. 4; Fig. 6 is a developed view of a reinforcing braai showing a second embodiment of the present invention, Fig. 7 is a cross-sectional view taken along the arrow ■-■ in Fig.
FIG. 9 is a cross-sectional view of a reinforcing layer constructed by laminating layers, and FIG. 9 is a cross-sectional view of a reinforcing layer showing a third embodiment of the present invention. 1... Pneumatic radial tire 2... Carcass layer 3... Cord 6... Belt layer 15... Reinforcement layer 17.24.32...
・Band-shaped body 18... Reinforcement element 19.21.31...
Covering member 20...Ear portion 22...Mountain 23...Valley a...Wavelength S, C...Width
d...Interval h...Amplitude

Claims (3)

[Claims] (1) A toroidal carcass layer in which a large number of cords extending in the radial direction are embedded, a belt layer placed radially outside the carcass layer, and reinforcement placed radially outside the carcass layer and overlapping with the belt layer. A pneumatic radial tire comprising: a pneumatic radial tire comprising: a pneumatic radial tire comprising a plurality of reinforcing elements bent in a wavy or zigzag shape and having the same phase and covered with a covering member made of a polymeric material having a low elastic modulus; A pneumatic radial tire characterized by being constructed by winding a band-shaped body in a spiral shape multiple times in the circumferential direction. (2) The wavelength of the reinforcing elements of the band-shaped body is made to be an integer fraction of the outer circumference length of the carcass layer, and both ends of the covering member are placed outward from the outermost two reinforcing elements by approximately 1 the distance between the reinforcing elements. 2. The pneumatic radial tire according to claim 1, wherein the ears are formed by protruding by 0.2 mm, and the outer ends of these ears are abutted against each other to join adjacent strips. (3) The covering member is made to extend linearly, and its width is approximately equal to the distance between the reinforcing elements from the peak of the reinforcing element located at one end to the valley of the reinforcing element located at the other end. 2. The pneumatic radial tire according to claim 1, wherein adjacent strips are joined by forming a constant width and overlapping the side edges of the covering members by an amount approximately equal to the amplitude of the reinforcing element. (4) The covering member is made to extend in a straight line, and the distance from the peak of the reinforcing element located at one end to the valley of the reinforcing element located at the other end is an integer of 3 or more as the amplitude of the reinforcing element. The width of the covering member is set to the same value as the distance multiplied by A, and the width of the covering member is set to a constant value obtained by adding approximately the spacing between the reinforcing elements to this distance, and the width of the covering members is set to be equal to the amplitude of the reinforcing element by 2 or more and the above-mentioned 2. The pneumatic radial according to claim 1, wherein adjacent strips are joined by overlapping each other by an amount substantially equal to an amount multiplied by an integer B that is more than 1/2 times and less than 1 times the integer A. tire.