JPH01229702A - Pneumatic bias tire - Google Patents

Abstract

PURPOSE:To improve the high speed durability of a tire decreased in its inside heat generation and accumulation by setting a cord of a carcass layer with at least two layers adjacent parallelly mutually between plies, in case of the bias tire having three or more carcass layers. CONSTITUTION:A bias tire has a crown part 1, shoulder part 2, side part 3, bead part 4 and a tread 5 respectively while three or more carcass layers 6. While in addition, the tire has a bead wire 7 and a breaker layer 8, respectively. In this constitution, a cord 6a of at least the two adjacent carcass layers 6 is parallelly set mutually between plies. The tire, for instance from its inside to outside, sets the cord 6a of each of the first through the third carcass layers 6 parallelly mutually between plies. While the tire, setting the cord of the third and the fourth carcass layers to be crossed while the cord of the fourth through the sixth carcass layers to be parallel, successively thereinafter repeats the setting of parallel and crossing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a pneumatic bias tire that reduces heat generation and heat accumulation inside the tire during running and improves high-speed durability.

[Prior art]

Conventionally, in a pneumatic bias tire, the cords 6a of the carcass layer 6 cross each other between flies, as shown in FIGS. 5 and 6. This was done in order to offset the direction of the force applied to each fly during running between adjacent flies and to ensure uniformity of the fly as a whole. In addition, in these figures, 1 is a crown part, 2 is a shoulder part, 3 is a side part, 4 is a bead part, 5 is a tread, and 7
8 represents a bead wire, and 8 represents a plaker layer.

However, if the code 6a is crossed in this way,
During running, the carcass layer 6 moves differently between adjacent flies, and the rubber between each fly receives forces in different directions, causing internal stress, which causes the carcass layer to generate a high amount of heat. There was a problem that separation occurred between the fries.

Therefore, in order to avoid this problem as much as possible, each fly has an appropriate thickness dl above and below the cord 6a as shown in Figure 7.
, d2. d3. d4. The rubber having ...- is coated,
This covering rubber served as a buffer layer that alleviated the internal stress of each fly, thereby suppressing the occurrence of separation. However, in the case of multilayer fly tires, these covering rubbers increase the thickness of the carcass layer as a whole and become a factor in accumulating heat generation, which has an unfavorable effect on durability at high speeds. In particular, as shown in FIG. 6, the shoulder portion 2 of the tire has a large amount of heat accumulated due to its thick rubber, and is a region where failures are likely to occur due to heat generation inside the tire.

[Purpose of the invention]

The present invention has been made to solve these problems, and it reduces heat generation and heat accumulation inside the tire during running, prevents separation between flies, and improves high-speed durability. The purpose of the present invention is to provide a pneumatic bias tire.

[Structure of the invention]

The present invention relates to a tire having a multilayer bias fly, in which the cords of some adjacent flies are arranged in parallel to each other, thereby omitting or thinning the cord covering rubber between these flies. In order to maintain the uniformity of the flies in the tire as a whole, it is preferable that these multiple layers of parallel fly groups are stacked such that the cords intersect with other multiple layers of parallel fly groups. , care is taken to ensure that the tires do not interfere with the running characteristics of the tires. That is, to summarize, the present invention provides a pneumatic bias tire having three or more carcass layers, characterized in that cords of at least two adjacent carcass layers are parallel to each other between flies. The main topic is tires.

Hereinafter, the configuration of the present invention will be explained in detail with reference to the drawings. Note that the same parts as in FIGS. 5 and 6 are as follows:
Represented by the same number.

FIG. 1 is a partially cutaway perspective view of an example of a pneumatic bias tire of the present invention in which the carcass layer is 12 layers, and FIG. 2 is a half-sectional view in the meridian direction thereof.

In the tire shown in FIG. 1, the first, second, and third cords 6a of the carcass layer 6, counting from the inside to the outside of the tire, are parallel to each other between the flies, and the cords 6a of the No. 3 and No. 4 carcass layers are parallel to each other between the flies. Intersect, make No. 4, No. 5, and No. 6 parallel, and No. 6 and No. 7
Intersect the 7th, 8th, and 9th parallels,
Cross No. 9 and No. 10, No. 10, No. 11,
No. 12 is parallel.

As the cord 6a of the carcass layer 6, for example, an organic fiber cord such as a nylon cord or a polyester cord is used.

In this way, four parallel fly groups in which the cords 6a are arranged parallel to each other between the flies are stacked so that the cords intersect with each other, so it is only necessary to provide a rubber buffer layer on the boundary surface of each group. The amount of rubber in the carcass as a whole can be reduced, which is advantageous for heat storage in the tire, and the carcass layer 6 of each fly in the parallel fly group moves in the same way between the flies during running, so stress is applied between the parallel flies. concentration will not occur, and heat generation can be suppressed.

The tire of the present invention is produced by laminating parallel-arranged fly groups with thin coated rubber gauges as part of the carcass during tire molding, forming a cylindrical tire, forming this into an annular tire, and further vulcanizing it. As shown in Figure 2, the tire is placed near the shoulder part of the carcass 6.
b undergoes large deformation during the tire molding and vulcanization process, the cords of adjacent parallel fly groups bite into each other, reducing the thickness of the entire carcass layer. In addition, at this time, when stacking the flies of the group of parallelly arranged flies, the - number of flies are stacked and bonded together in a cylindrical shape while shifting the pinch.
So-called spiral pasting becomes possible, and productivity can be improved.

FIG. 3 is an explanatory half-sectional view of the other side of the pneumatic bias tire of the present invention in the meridian direction.

FIG. 3 shows a case in which there are three carcass layers, and shows a case in which two adjacent carcass layers are stacked on top of each other and the coat rubber gauge is thinned.

In order to confirm the effect of the present invention, tire size 10.00
-2014PRY67 (carcass layer cord: nylon fiber cord), load 2470 kg, speed 50 k
A heat generation test was conducted using an indoor rotation test under conditions of m/h. In this case, the running time (minutes) at point A on the outermost carcass layer, which corresponds to shoulder point 9 in FIG.
By looking at the temperature change over time. The results are shown in Fig. 4 (measured on the left and right sides of the tire with N = 1).
respectively show the conventional tire (structure shown in Fig. 5.6). From FIG. 4, it can be seen that the tire of the present invention has excellent heat resistance.

〔Effect of the invention〕

As explained above, according to the present invention, since the cords of at least two adjacent carcass layers are made parallel to each other between the flies, the following effects can be achieved.

- Since the carcass layers move in the same way between the parallel plies during running, heat generation and separation between the flies can be prevented, thereby improving high-speed durability.

■ Since the covering rubber gauge between the flies can be eliminated, the overall gauge from the crown part to the shoulder part, which contacts the road surface and generates heat, becomes thinner, resulting in a reduction in heat storage due to the heat dissipation effect, which improves heat resistance and high-speed durability. It can be improved further.

(2) Since it is possible to form a coating rubber gauge between the flies, material costs can be reduced.Furthermore, it is possible to form the carcass layer in a so-called spiral pattern during tire molding, so productivity can be improved.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective explanatory view of an example of the pneumatic bias tire of the present invention, Fig. 2 is an explanatory half-sectional view in the meridian direction thereof, and Fig. 3 is a meridian direction of the other side of the pneumatic bias tire of the present invention. FIG. 4, a half-sectional explanatory diagram, is a diagram showing the relationship between running time and tire internal temperature. FIG. 5 is a partially cutaway perspective explanatory view of an example of a conventional pneumatic bias tire, and FIG. 6 is an explanatory half-sectional view in the meridian direction.
FIG. 7 is a partial cross-sectional view of the carcass layer. 1-Crown part, 2--Part of shoulder, 6--Carcass layer, 6a--Cord, 7--Bead wire, 8--Breaker layer. Agent Patent Attorney Nobuo Ogawa −

Claims (1)

[Claims] 1. A pneumatic bias tire having three or more carcass layers, characterized in that the cords of at least two adjacent carcass layers are parallel to each other between flies.