JPS6094807A - Pneumatic tire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pneumatic tire using a knitted fabric as a bead reinforcing layer.

Generally, the bead reinforcement layer of pneumatic tires is made of a fabric in which tire cords, which serve as reinforcing elements, are arranged as warp threads, and the weft threads, which are thinner than the warp threads, are loosely woven in a plain weave in order to maintain the spacing between the warp threads. Weaving is done by opening the warp threads alternately, driving the weft threads in with a shuttle, and then beating the warp threads upside down, opening the warp threads upside down, and driving the weft threads in again.

The woven plain woven fabric is then subjected to a dip treatment and a topping treatment to produce plies, but there is a problem in that the fabric structure is easily disturbed during these steps (so-called misalignment). Therefore, the density of the textile structure cannot be made coarser than a certain level.

In the present invention, the bead portion reinforcing layer is disposed adjacent to the folded portion of the carcass ply, and has the function of reinforcing the bead portion and alleviating stress concentration in the folded portion. light truck tires,
Used in motorcycle tires, etc.

As a method to prevent fabrics from shifting, there is so-called karami-ori, which uses two or three warp threads to weave the weft threads from above and below, but this method has the drawbacks of a complicated weaving process, high cost, and low productivity. . Therefore, the present invention uses a knitted fabric, which will be described later, as a bead reinforcing layer, thereby suppressing the movement of warp yarns during processing steps such as depping, maintaining uniform end distribution, and improving tire durability. This is based on the fact that

In the present invention, the warp threads are arranged parallel to each other and the weft threads are arranged so as to intersect the warp threads at an angle of 60° to 90° without weaving, and these warp threads and weft threads are knitted with silk threads of thin filament yarns. This is a pneumatic tire that uses knitted fabric ply as the bead reinforcement layer.

An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a schematic diagram of the front side of the silk cloth used for the reinforcing layer of the pneumatic tire of the present invention, and FIG. 2 shows a schematic diagram of the back side. In the figure, the knitted fabric (1) has warp threads (2) arranged parallel to each other, and weft threads (
3) are arranged at the same density as the warp threads. These warp and weft threads are knitted with fine fiber cotton threads (4) along the longitudinal direction of the warp threads, thereby integrating the warp threads and weft threads to form a silk cloth. The knitting method here can be a conventionally widely used method such as warp stockinette knitting or horizontal stockinette knitting.

Various materials can be used for the warp threads, including organic fibers such as nylon, polyester pereyon, and aromatic polyamide, and inorganic fibers such as steel and glass fibers.

In addition, the weft is preferably made of the same material and has the same thickness as the warp, but has sufficient strength to prevent it from being cut by the tension during the adhesion process or the tension during the rubberizing process during other tire manufacturing processes. For example, the strength after adhesion treatment is 100 g or more. It is not necessary to specifically select a material for the weft yarns that suppresses movement more than the warp yarns. Furthermore, long fibers, which are not often used in plain weave because the warp threads slip, can also be used in the present invention. Also, the weft is 80 to 140 thicker than the warp.
% range can be used.

Next, the silk thread used in the present invention may be made of any material that can sufficiently withstand general adhesive treatment and heat treatment conditions in the tire manufacturing process and can adhere to rubber after treatment, such as nylon-6, nylon-66, polyester. Filaments of organic fibers such as those having a fiber diameter of 5 to 50 deniers are used. If the filament diameter is smaller than 5 deniers, the fixing strength between the warp and weft is not sufficient. On the other hand, when the filament diameter exceeds 50 deniers, the thickness of the knitted fabric increases, and as a result, the ply gauge increases, which is disadvantageous from the viewpoint of weight reduction. The arrangement density of the weft yarns is preferably substantially the same as that of the warp yarns, and is usually 80-140.
Selected within a range of %.

The silk fabric obtained as described above is subjected to a conventional adhesive treatment and heat treatment, followed by a topping rubber treatment, and a cord is embedded in the rubber to form a ply. This ply is then cut at an angle of 20° to 70° with respect to the warp to produce strips, which are applied to the bead portion during the assembly of cylindrical tires on conventional building drums. Here, the warp threads of the reinforcing layer are arranged at a predetermined angle with respect to the tire equatorial plane, corresponding to the cutting angle of the ply described above, and
The weft yarns arranged at right angles to the warp yarns or at 60° to 90° form a bias configuration. Here, the weft yarns have substantially the same thickness and embedding density as the warp yarns, and thus function as reinforcing elements in the same way as the warp yarns.

A cross-sectional view of the pneumatic tire thus formed is shown in FIG. In the figure, the carcass (11) is folded back around the heat core (10) so that its both ends are locked, and the bead core (
1o> A reinforcing layer (12) is arranged adjacent to the folded portion (11a). Of course, in the present invention, two or more plies can be used for the reinforcing layer.

The pneumatic tire of the present invention has the following advantages over tires using conventional plain weave fabrics.

(b) Since the warp and weft of the reinforcing material are fixed, the end distribution is uniform, improving the uniformity of the tire and improving its durability.

(b) Since the silk fabric of the present invention is not woven, productivity is improved, and since there is no warp weaving shrinkage, material costs can be reduced.

In addition, in the present invention, the knitted fabric (5) is made of two knitting yarns (5), as shown in FIGS.
) (6), it is possible to more effectively prevent misalignment between warp and weft threads.

[Brief explanation of the drawing]

Figures 1, 2, 4, and 5 are schematic diagrams of knitted fabrics;
The figure is a sectional view of the tire of the present invention. 1.5 Silk Cloth, 4.6.7 Knitting Yarn 2 Warp 1O-Bead Core 3 Weft 11 Carcass 12 Reinforcement Layer Patent Applicant Sumitomo Rubber Industries Co., Ltd. Agent Patent Attorney Yoshihira Nakamura No. 1 Figure 2 Group Figure 1

Claims (2)

[Claims] (1) The warp threads are arranged parallel to each other, and the warp threads have 6
A pneumatic tire in which the weft yarns are arranged without weaving so as to intersect at an angle of 0° to 90°, and the warp yarns and weft yarns are knitted with fine fiber knitted yarns, and a braai fabric is used as the bead reinforcement layer. . (2) Knitting yarn is nylon-6, polyester, nylon-6
2. The tire according to claim 1, wherein the tire is made of organic fiber filaments such as No. 6 and has a denier of 5 to 50.