JPH0214084A - Steel cord for reinforcing rubber structure - Google Patents

Abstract

PURPOSE:To improve adhesive properties of rubber materials to respective element wires by twisting a strand group of intertwisted plural element wires, etc., with one element wire, etc., and further intertwisting plural element wires and providing different twisting directions, etc., of mutually adjacent twisted element wire groups. CONSTITUTION:Plural element wires 1 or strands are intertwisted to form a twisted wire group (A), which is then intertwisted with one element wire 2 or strand or plural element wire or strand bundles without mutually intertwisting to form a twisted wire group (B). The resultant twisted wire group (B) is then intertwisted with plural element wires 3 to provide the twisting direction of mutually adjacent twisted wire group different from at least one twisting pitch. Thereby, a steel cord (C) is constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) 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.

(Prior art) A conventional steel cord is made by twisting a plurality of strands a to form a steel cord S, as shown in Fig. 4 (a) and (0).
It consists of

(Problem to be Solved by the Invention) In each of the steel cords S, each strand is in close contact with each other, so when covered with a rubber material, the rubber material does not penetrate into the center of the steel cord, and the steel cord S A space X is created at the center of the wire, and the rubber material does not wrap around the entire circumference of each strand a, resulting in insufficient adhesion to the rubber material, and the elasticity is also not satisfactory.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a steel cord that has improved adhesiveness between the rubber material and each strand and elasticity in the longitudinal direction.

(Means for Solving the Problems) In order to achieve the above object, the steel cord of the present invention has a stranded wire group A twisted with two or more strands or wires.
and strand group B, which is a combination of one wire or strand, a wire bundle of two or more wires that are not twisted together, or a strand bundle that is not twisted with two or more strands. It is made up of different things.

Moreover, the above-mentioned twisted wire group B may be used as a core strand, and two or more strands may be twisted together on top of the core strand.

Furthermore, it is preferable that the strands constituting the stranded wire group A, the strands constituting the stranded wire group B, and the strands constituting the cord C have the same wire diameter and the same twisting direction; It is also possible to vary the diameter.

By the way, the twisting directions of stranded wire group A (!: stranded wire group B and code C are all the same direction, but the twisting pitch can be selected appropriately. However, preferably, the twisting pitch is Maintaining the relationship between the pitch of group A < the pitch of twisted wire group B < the pitch of code C, and the code pitch C is 9
A range of ~13fi has the effect of improving elastic performance in the longitudinal direction.

(Example) Fig. 1 is a cross-sectional view showing an example of the steel cord of the present invention. The twisted wire group A is formed by twisting the wires so that the twisting pitch is 5, and the twisting pitch is S. This twisted wire group A and one wire (2) with a wire diameter of 0.25 m are twisted at a twisting pitch of 6.7111. Twist them together to form S-twist to form stranded wire group B.Furthermore, the above-mentioned stranded wire group B and two strands (3) and (31) each having a diameter of 0.25 m are twisted at a twist pitch of 10 to form S-twisted wires. Steel cord C is constructed by twisting them together so that

Next, the steel cord C of the above embodiment and the conventional steel cord shown in FIG.
When the physical properties were compared with S-twisted steel cord S, the results shown in the following table were obtained.

Therefore, the steel cord of the present invention is superior to conventional steel cords in terms of both rubber penetration rate (rubber penetration cross-sectional area/rubber penetration possible cross-sectional area) X100 and fatigue resistance 1 elasticity modulus. In the example, it was found that the same number of strands of strands had the same or higher quality, which was a very large effect.

Next, FIG. 3 shows an example of a stranding device for manufacturing the steel cord C of the above embodiment, and the method for manufacturing the steel cord will be described below based on this drawing.

In Fig. 3, the wires (1), (11, (2) are wound around a rotatably mounted reel (4), and are placed in a cradle (
5). The strands (1), (1) pass through the shaft center via the turn roller (8) and the rotating plate (
The wire passes through the guide roller (7) of 6), rotates around the cradle (5), and is guided to the other axis while being twisted, and is twisted twice to form wire group A. The wire (2) is
The wires are led directly through the other axis of the rotating body, and are partially twisted and twisted together with the twisted wire group A to form the twisted wire group B. This twisted wire group B passes through a turn roller (8) and is introduced into a perforated plate (9) and a voice Ql. Above twisted wire group B
At the same time, the side wire (3) let out from the reel aυ passes through the turn roller (8) and is guided into the batten (9). The twisted wire group B and the side wire (3) coming out of the voice αω are connected to an over-twisted roller (2 ), passes through the axis of the rotating body (2), passes through the guide roller Q4) of the rotary plate a1, passes through the other axis and is guided into the cradle α9, where it is twisted twice. The twice-twisted strands change direction from the axis of the rotary plate αl by a turn roller αe, are rotatably installed in a cradle α9, and are rotated in the same direction as the rotary body ■ by a timing belt α, but at a slower speed. It is wound several times around the over-twisted roller α, which rotates at a speed of about 0.8 times the rotational speed of the rotating body (2). By further twisting the stranded wire that has reached the specified twisting pitch, the twisting pitch is made smaller than the above-mentioned twisting pitch, thereby imparting permanent strain to the stranded wire. The stranded wire exiting the over-twisted roller α becomes a stranded wire that has returned to the specified pitch and is taken over by the take-up capstan OI, passed through a traverse roller (toward), and wound onto the take-up reel R21J to form a multi-layer twisted steel cord. It becomes C. In addition, (2) in the figure is the drive timing pulley,
(23 is a drive motor.

By the way, the steel cord C is a strand of wire with the same diameter.
Although the twist configuration was +1+2, Figure 2 (A) to (N)
are steel cords of different embodiments, and (A) is a wire of the same diameter with a 2+1+6 twist configuration, (II+) ~
(D) is a wire with a different diameter, and (El) is 2×2+2+2.
(c) is 2X2+2+8. (=) is 2 +2
+2. (N) are strands of the same diameter, each having a 2X2+2+2 twist configuration.

(Effects of the Invention) Since the steel cord according to the present invention has the above-mentioned structure, rubber can easily penetrate into the inside of the steel cord.
Adhesion to rubber is greatly improved.

In addition, since the elastic performance of the steel cord in the longitudinal direction has been improved, the ability to follow the elastic deformation of the rubber is better, the breakage of the steel cord is reduced, and the performance of the tire is further improved, which has remarkable effects.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the steel cord according to the present invention, Fig. 2 is a sectional view of the steel cord according to the present invention;
Figures (A) to (N) are cross-sectional views of steel cords of other embodiments, Figure 3 is a configuration diagram showing an example of a stranded wire manufacturing apparatus used for the steel cord of the present invention, and Figures B) is a cross-sectional view of a conventional steel cord. (1), (21, (31... strand, A, B.
...Twisted wire group, C...Figure 1\

Claims (1)

[Scope of Claims] A stranded wire group A consisting of one or more strands or strands, and a strand bundle or two consisting of one strand or strand or two or more strands that are not twisted together. Two or more strands are further twisted into the twisted wire group B, which is made by twisting together a bundle of strands that are not twisted together, and are at least one of the twisting direction and twisting pitch of the stranded wire group that are adjacent to each other. Steel cord for reinforcing rubber structures made of different types of cords. 2. The steel cord for reinforcing a rubber structure according to claim 1, wherein the twisted wire group B is used as a core strand, and two or more strands are twisted together on the core strand. 3. The steel cord for reinforcing a rubber structure according to claim 1 or 2, wherein all the strands have the same strand diameter and are twisted in the same direction.