JP4166371B2 - Steel cord manufacturing method and stranded wire machine used in this method - Google Patents

Description

【００２７】
【発明の効果】
この発明によれば、素線の集合そして撚り合わせを無拘束下で行うとともに、この撚り合わせを無理なく行えるために、優れた真直性に併せて素線の均等配置をも実現することができる。
【図面の簡単な説明】
【図１】 チューブラー撚線機を示す模式図である。
【図２】 撚り合わせにボイスを用いた撚線の説明図である。
【図３】 撚り合わせに撚り合わせガイドを用いた撚線の説明図である。
【図４】 撚り合わせガイドにリングを用いた撚線の説明図である。
【図５】 図６に示す実験におけるＡ部およびＢ部を示す模式図である。
【図６】 素線毎の型付け量を示すグラフである。
【図７】 プレホーム装置を示す模式図である。
【図８】 真直性の評価要領を示す図である。
【符号の説明】
１ コア
２ ボビン
４ａ〜４ｆ 素線
５ａ〜５ｆ ボビン
６ プレホーム装置
７ ボイス
８ 撚り合わせガイド[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a steel cord and a tubular type twisted wire machine used in this method, and more particularly to a tubular twisted wire machine having a preform device.
[0002]
[Prior art]
Steel cords that reinforce rubber articles such as pneumatic tires and conveyor belts are generally manufactured by twisting a plurality of strands. For twisting the strands, as shown in FIG. Tubular type twisting machines are often used.
[0003]
For example, a 3 + 6 layer twisted cord applied to a pneumatic tire can be manufactured by winding and twisting six strands as a sheath around a 1 × 3 structure core. . That is, as shown in FIG. 1, the bobbin 2 around which the core 1 is wound is disposed outside the barrel 3, while the bobbins 5a to 5f around which the sheath wires 4a to 4f are wound are disposed inside the barrel 3. The core 1 and the sheath wires 4a to 4f are drawn out onto the barrel 3 and the barrel 3 is rotated, whereby twisting is performed. Usually, on the exit side of the barrel 3, a preform device 6 as shown in FIG. 1 performs a spiral-shaped molding process in the same shape as a state in which the sheath strands are twisted. As a result, the twisting is completed and the cord C is obtained.
[0004]
Here, the steel cord is mainly required to have two basic performances. First, one of them is straightness. If this straightness is inferior, for example, the treating material is warped in the calendering process of tire production, which causes troubles in the joining of the treating material. Next, for example, in order to increase the durability of the tire, it is required that the rubber penetrates into the inside of the cord and has excellent rubber permeability. Specifically, the cord shape has a sheath element in its cross section. It is advantageous for the rubber to penetrate into the core of the cord that there are gaps between the lines and the number of the gaps is large. For this purpose, it is important that the sheath wire is evenly arranged around the core without being biased in the cord cross section.
[0005]
In order to evenly arrange the sheath wire around the core, it is effective to make the sheath wires uniform before twisting. Furthermore, if the sheath wire is in the same phase, the strands may interfere with each other during twisting, causing the strands to protrude from the outer diameter of the cord. Since there will be nothing, the decline in image as a product is inevitable.
[0006]
As described above, as the characteristics of the steel cord, straightness and uniform arrangement of the sheath filament are required, but straightness cannot be ensured with the conventional twisting machine as shown in FIG.
[0007]
That is, in the method using the voice 7 by the preform device 6 and the dice or the like, as shown in FIG. 2, even if uniform molding is performed on each strand by the preform device 6, a plurality of strands are formed. When the wires are introduced and assembled into the voice 7, the strands are subjected to a bending process at the entrance side of the voice 7 and are plastically deformed, so that the straightness of the strands, and thus the straightness of the cord, is deteriorated.
[0008]
As a method for suppressing the deterioration of straightness in the twisted gathering portion of the voice, instead of the voice, as shown in FIG. 3, a sheath strand is passed through an annular twisted guide 8 having a diameter larger than the diameter of the cord. There is a method of twisting the assembly point P of the wires with the exit side of the twisting guide 8. In this method, since plastic processing is not performed at the assembly point P of the strands, excellent straightness can be obtained.
[0009]
[Problems to be solved by the invention]
However, when the strands are gathered and twisted on the exit side of the twisting guide 8, there is a case where the strands are not evenly arranged because there is no restriction like the method shown in FIG. That is, since the molding in the preform device 6 is uniform between the strands, when the unconstrained twisting shown in FIG. 3 is performed, the strands interfere with each other, resulting in disordered strand placement. A uniform wire arrangement is not realized.
[0010]
Accordingly, an object of the present invention is to provide a method for obtaining a cord in which strands are evenly arranged even when assembly and twisting of strands are performed under unconstrained conditions. It is to be provided together with the machine.
[0011]
[Means for Solving the Problems]
That is, the gist configuration of the present invention is as follows.
(1) After forming a plurality of strands, respectively, when assembling and twisting the strands on the guide exit side via the twisting guide, the phase of typing applied to each strand is shifted between the strands. A method of manufacturing a steel cord characterized by the above.
[0012]
(2) A method for manufacturing a steel cord according to the above (1), wherein the phase of typing applied to each strand is shifted by the strand diameter between adjacent strands.
[0013]
(3) A tubular stranding machine in which strands fed out from a plurality of bobbins are respectively molded by a preform device, and then the strands are assembled and twisted on the guide exit side via a twisting guide. The preform device is formed by arranging a plurality of brazing pins through which the strands are passed in a staggered pattern in the direction of the prisms on each side surface of the polygonal columnar body, and the position of the brazing pin group on the side surface. Tubular twisting machine characterized in that it is shifted in the direction of the bus bar between.
[0014]
(4) In the above (3), a tumbler stranding machine characterized in that the position of the brazing pin group is shifted by the strand diameter in the direction of the bus between adjacent side surfaces.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The twisting machine according to the present invention can be obtained by using a twisting guide for the assembly of the strands without relying on the voice, thereby performing the assembly of the strands and the twisting on the exit side of the twisting guide. The code will be straight. However, when a twist guide is used, it is a new problem that the arrangement of the strands is disturbed.
[0016]
Therefore, in order to investigate the twisting behavior of the strands on the exit side of the twisting guide, as shown in FIG. 4, the sheath strands were twisted using a ring as the twisting guide 8. It came to obtain knowledge.
That is, a plurality of strands that have been uniformly typed by the preform device 6 try to twist at one point on the exit side of the twisting guide 8, but the phase of the typing is uniform between the strands. It is impossible to twist them as they are. Actually, it is confirmed that the twisting guide (ring) 8 arranged in the direction orthogonal to the axis of the cord is inclined as shown in the figure during the twisting, and this is a phase shift Z between the strands in the twisting portion. This is because of this. Thus, it has been clarified that the uneven arrangement of the strands in the twisted portion is caused by the fact that the phase of the molding is uniform among the strands.
[0017]
Furthermore, as shown in FIG. 5, the molding of each strand was investigated in the A part after passing through the preform device 6 and the B part after twisting. As shown in FIG. 6, the difference in the amount of die is slightly changed in part A before twisting, whereas the amount of die is largely changed in the strand of cord after twisting. Also from this result, it can be seen that interference between the strands occurs at the twisted portion, and the uniform arrangement is hindered.
[0018]
From the above examination results, in twisting using a twisting guide, it was found that it is important to shift the molding phase between the strands in order to avoid unequal arrangement of the sheath strands. did. Then, as a result of earnest investigations on means for shifting the phase of molding, the effectiveness of the following means was confirmed and the present invention was completed.
[0019]
First, it is effective to adjust the molding position in the preform device for each strand in order to shift the molding phase between the strands at the twisting set point. That is, as shown in FIG. 7 (a), the preform device 6 includes, for example, a plurality of, for example, four brazing pins 61 to 64 on each of the six side surfaces 6-1 to 6-6 of the hexagonal column. It is arranged in a staggered pattern in the generatrix direction of the hexagonal column, and the strands are typed by passing the strands through the brazing pin groups 61 to 64 of the side surfaces 6-1 to 6-6. In this preform device 6, the position of the side brazing pin group is shifted between adjacent brazing pin groups, and the phase of the spiral brazing of the strands is shifted in the length direction between the strands. Do not disturb the twisting of the wires.
[0020]
For example, as shown in FIG. 7B, between the side surfaces of the preform device 6, the pin spacing in the bus bar direction of the brazing pin group and the pin spacing in the direction orthogonal to the bus bar are not changed. By shifting the relative positions, the phase of the molding can be shifted between the strands at the gathering point of twisting. Here, the amount of shifting between the brazing pin groups is preferably the amount of shifting between adjacent side surfaces within the range in which the molding does not synchronize between the strands.
[0021]
【Example】
Inventive example 3 strands (0.20 mm diameter) twisted together at a twist pitch of 10 mm. Around the core, 6 strands with a diameter of 0.36 mm were wound at a twist pitch of 18 mm. When twisting the cord using a tuber twisting machine, as shown in FIG. 7, as shown in FIG. 7, the arrangement of bobbins in the barrel passes through the brazing pin group through which the wire fed out from the bobbin far from the preform device 6 passes. The relative positions of the brazing pin groups between the side surfaces of the preform device 6 are arranged with a shift amount of 0.36 mm in the direction of the bus line so as to be far from the side. In addition, the pin arrangement in each brazing pin group was such that the pin spacing was 7.65 mm in the bus bar direction and 0.935 mm in the direction orthogonal to the bus bar, and the processing amount was the same.
[0022]
Here, the shifting amount of the brazing pin group is a difference in the bus bar direction of the relative position of the brazing pin group between the adjacent side surfaces of the preform device, and sequentially between adjacent side surfaces below this shifting amount. The brazing pin group was shifted.
[0023]
Conventional examples 1 and 2
Also, as a comparison, as in the prior art, a preform device having the same arrangement of brazing pin groups and the same biting amount between each pin group, and voice (conventional example 1) or twisting in twisting A stranded wire using a guide (conventional example 2) was also performed.
[0024]
For the cords obtained according to the above-mentioned conformation example 1 and conventional examples 1 and 2, the straightness and the arrangement of the strands were evaluated. That is, the straightness is determined by cutting the obtained cord into a length of 50 cm and placing the cord on a flat horizontal surface without restraint, as shown in FIG. Measured and evaluated. It shows that it is excellent in straightness, so that this figure is small. For the arrangement of the strands, loosen the cord, observe the magnified shape of each strand with a projector, measure the wave height of the waveform type of each strand, and set the maximum difference in the height between the strands. Displayed. It shows that it is arrange | positioned equally, so that this figure is small.
[0025]
As shown in Table 1, the results of these investigations can be obtained by using the twisted wire machine of the present invention to obtain a cord that is excellent in straightness and in which the strands are uniformly arranged.
[0026]
[Table 1]

[0027]
【The invention's effect】
According to the present invention, the assembly and twisting of the strands are performed under unconstrained conditions, and the twisting can be performed without difficulty, so that the uniform arrangement of the strands can be realized in addition to excellent straightness. .
[Brief description of the drawings]
FIG. 1 is a schematic view showing a tubular stranded wire machine.
FIG. 2 is an explanatory diagram of a stranded wire using a voice for twisting.
FIG. 3 is an explanatory diagram of a stranded wire using a twist guide for twisting.
FIG. 4 is an explanatory view of a stranded wire using a ring as a twist guide.
FIG. 5 is a schematic diagram showing part A and part B in the experiment shown in FIG. 6;
FIG. 6 is a graph showing a typing amount for each strand.
FIG. 7 is a schematic view showing a preform device.
FIG. 8 is a diagram showing a straightness evaluation procedure;
[Explanation of symbols]
1 Core 2 Bobbin 4a-4f Wire 5a-5f Bobbin 6 Preform device 7 Voice 8 Twist guide

Claims (4)

  After forming a plurality of strands and then twisting the strands on the guide exit side via the twisting guides, the phase of molding applied to each strand is shifted between the strands. A method for producing a steel cord.   2. The method of manufacturing a steel cord according to claim 1, wherein the phase of molding applied to each strand is shifted by the strand diameter between adjacent strands.   A tubular stranding machine, in which strands fed out from a plurality of bobbins are each molded by a preform device, and then the strands are assembled and twisted on the guide exit side via a twisting guide, The preform device is formed by arranging a plurality of brazing pins through which the strands are passed on each side of the polygonal columnar body in a staggered manner in the direction of the bus bar of the prism, and the position of the brazing pin group between the side surfaces. A tumbler stranding machine characterized by shifting in the direction.   4. The tumbler stranding machine according to claim 3, wherein the position of the brazing pin group is shifted between adjacent side surfaces by the strand diameter in the direction of the generatrix.

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