JPS5898487A - Steel cord - 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 steel cord for reinforcing rubber structures (hereinafter simply referred to as steel cord) used as a reinforcing material for tires, belts, etc.

In general, this cypress steel cord has multiple lengths of 1m)
It is configured accordingly. A plurality of these steel cords are arranged in parallel and covered with rubber material in good condition, and are used as reinforcing materials for tires, belts, etc.

Accordingly, when steel cord is used as a reinforcing material, an essential requirement is that it must be chemically bonded to rubber material.
(It is adhesion and the rubber material penetrates well into the steel cord.)

That is, in order for the steel cord to fully fulfill its role as a reinforcing material, it is necessary that the steel cord and the rubber material be completely integrated.

For example, when used in tires, if the adhesion to the steel cord material and the infiltration of the rubber material into the interior of the steel cord are poor, the so-called separation phenomenon in which the steel cord and the rubber material will separate when the car is running will occur, causing the tire to deteriorate. In addition to significantly impeding the function of the steel cord, moisture in the rubber and moisture that has entered through cuts in the rubber can cause rust to occur in the strands of the steel cord, greatly reducing the strength of the steel cord and causing damage to the above-mentioned separates. This has the disadvantage of accelerating the phenomenon.

However, as shown in FIG. 1 U)--), a conventional steel cord 1 is constructed by twisting 9 pieces of multiple-rate elements 2 together.

In the steel cord 1 mentioned above, the elements @2 are almost in close contact with each other, and when covered with a rubber material, the rubber material does not penetrate to the center of the steel cord, and a space A is created at the center of the steel cord 1. -2 had the drawback that the rubber material did not wrap around the entire circumference, resulting in insufficient adhesion to the rubber.

For this reason, recently, steel cords have been developed in which the rubber material penetrates into the center of the steel cord and is bonded to all the strands of the wire.

This steel cord is a sweet steel cord 1 (0pen constructio
(sometimes referred to as n).

But top 11! A company with a sweet steel cord,
During the manufacture of steel cords, the twisted structure tends to become unstable, and as shown in Figure 5 K), (1'), No. 1) and 轡, a backbone was formed on the side of #2. A drawback is that the twist is uneven in the longitudinal direction of the steel cord. In such a case, even if the rubber material penetrates to the center of the steel cord, when buckling stress occurs in the steel cord, stress concentration occurs, and the multi-rate cable wires that make up the steel cord have an effect as a whole. It has the disadvantage that it does not exhibit the same properties and is prone to fatigue damage. In addition, since the cord is not easy to twist, the cord elongates greatly when pulled under a low load, and the cord is plowed like a so-called elastic body, resulting in very poor workability.

However, if the steel cord also expands and contracts because rubber itself is an elastic body, the elongation of both will match well, and if the tensile tension is not controlled at a constant level, there will be a difference in elongation between the two (rubber and steel cord). We cannot expect it to become a complete complex.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and by using a core element wire having a nearly polygonal cross-sectional shape for the core of the steel soot, it is possible to prevent the rubber material from penetrating into the steel cord. Ensure that the rubber material and steel cord are in contact with each other in the longitudinal direction of the steel cord! ! The object of the present invention is to provide a steel cord that is stable, has the same fatigue resistance as above, and does not elongate to a large extent under low loads.

In other words, the non-invention is a steel cord having one core strand and six or six @ strands, in which the cross-sectional shape of the core strand is a polygon having a number of peaks corresponding to the number of side pieces. , and *** is a steel cord characterized in that each of these @Igllll is twisted so that it has K111 between each other, and each **** is almost in contact with the corresponding surface of the g element. .

The strands used in the invention may be plated with a steel alloy or the like on the different side in order to improve adhesion to the rubber material.
Since the shape of the core IA is intended to bring the IIl element into contact with the side thereof and to reduce movement, it is sufficient that the core IA has an approximately polygonal shape. Furthermore, the gap between these Ga element wires is usually Q,02 or more. In addition, @ strands are composed of strands of the same single pole, 1+3.1+4.1+
There are 5.1+6 configurations. Here, if the number of 1111 elements is set to 5 or 6, and if the number of 9 is less than 2, it will become unstable as a chord in terms of structure and Fi, and if it becomes more than 7, the shape of the 8 elements will be complicated. This is because thick V%411 must be used, which is inappropriate in terms of flexibility and the like.

Hereinafter, one embodiment of the invention will be described based on the drawings.

Figures 4 f1), (0), PM and 4) are sectional views showing the steel boot O-embodiment of the present invention, respectively.

U) in the same figure shows a steel cord having a 1+3 twist structure, and 3 side cables 7 are provided in contact with each surface around a core strand 5 having an approximately triangular cross section. each ii
ucm are twisted together so that they do not touch each other but have gaps. The M method is to make 8 pieces of irregular shape # with a triangular cross section, arrange 3 of them so that the precious elements are in contact with each side of the irregular shape machine, and twist them together with twice twisting and twisting 1ilfIA. be.

In the same figure, (-) is 1+4, (C) is 1+5, and (2) is uninvented steel cord showing 1,06 structure, each with a cross section of 4.
5. Hexagonal variant - is made into 8 lines @4.5.6, and each 1jiK side element -417 of the variant line is arranged and *b is combined.

Next, a comparative example will be shown between the steel cord of the present invention and a conventional steel cord.

Strain bit is 10 easy, S twist, strand diameter is α25~φ
The standard code of Figure 1 0) and the sweet 16 of Figure 2 6) constructed using the ! IJ) The conventional steel cord shown in the code has a rectangular cross section with a side of 0.25.111 mm (rounded corners and (1015R), and the side cords are a25
Table 1 shows a comparison of the number of occurrences of twisting, rubber penetration rate, fatigue resistance, initial wire elongation, etc. with the steel cord shown in No. 41 (Uninvention No. 41), which is Peng φ.

Table 1 1 Oil 11:158-98487 (3) As shown in the first group above, the uninvented steel cord has very little occurrence of twisted shins compared to conventional products, and the rubber penetration rate (rubber penetration breakage) Area/rubber penetration area n11 x 100) is also 100% and fatigue resistance is also superior to conventional products. Furthermore, compared to conventional twisted p-cords, this invention has less elongation of the cords at the W stage load (5 J) and is superior in workability.

[Brief explanation of drawings]

Figure 1 ←) Q: I) is a cross-sectional view showing a conventional steel cord, Figure 2 6) -) is a conventional twisted W
Cross-sectional view showing steel cord, Figure 5 B) IP) F-
3) and (E) are cross-sectional views showing the conventional steel cord in the open state, 2Jc4) (E-)r
1 and 2) are sectional views each showing an embodiment of the steel cord of the present invention. 1... Steel bud 2... Wood - 5, 4, 5, 6... Core sa 7... - Soichi Figure 1<4) C") Figure 2 (Go1'n)
(o) Figure 1 C-in (b)
(10 (=) residence) (in θsu Figure 1 41 (b) (d)

Claims (1)

[Claims] In a steel cord with one 8-arm edge and 5 to 6 1411-arm steel cords, the cross-sectional shape of the core material is similar to that of the side rope.
A polygon having the number of wires and the number of directions corresponding to
A steel cord characterized in that each of these bundles is twisted so as to have a gap between each other.