JPH0789377A - Manufacture of copper coated steel trolley wire - Google Patents

Abstract

PURPOSE:To provide a manufacturing method for a copper coated steel trolley wire, in which good conductivity is provided while sliding motion of a pantograph cause an exposure of a steel core in a short time so that reduction in conductivity and corrugated abrasion can be suppressed. CONSTITUTION:Firstly, a copper coated steel wire, which is coated with copper or copper allay around a steel core, is drawn by using a die provided with a projection part projecting toward the center, and a deformed copper coated steel wire 5 having a recess 8 in a part. of its coating layer is provided. Then, the deformed copper coated steel wire 5 is drawn so that its recess 8 side is located on a great arc face side, and consequently, the deformed copper coated steel wire 5 is formed into a trolley wire, in which the coating layer is thin on the great arc face side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a copper-coated steel trolley wire for supplying electric power to a train via a pantograph or the like while the pantograph or the like of the train slides.

[0002]

2. Description of the Related Art FIG. 5 is a sectional view showing a conventional copper-coated steel trolley wire. This type of copper-coated steel trolley wire is configured by disposing a coating layer 27 made of copper or a copper alloy around a steel core 26 having a circular cross section. On both sides of the upper half of the covering layer 27, there are 1
A pair of groove portions 28 are provided. With this groove 28,
The peripheral surface of the trolley wire is a small arc surface side 25a which is a fixture side,
It is divided into the large arc surface side 25b which is the contact surface side with the pantograph.

The copper-coated steel trolley wire has the advantage that the tensile strength is higher than that of the trolley wire made of only copper or copper alloy because the steel core has high mechanical strength. Moreover, since the coating layer of the copper-coated steel trolley wire is made of copper or a copper alloy, the conductivity is relatively good. In addition, the copper-coated steel trolley wire has a trolley wire that slides on the steel core and the wear rate of the trolley wire significantly decreases when the trolley wire wears and the steel core is exposed due to sliding of the pantograph. Alternatively, it has the advantages that it is superior in wear resistance and has a long life compared with a trolley wire made of only a copper alloy. For example, it has been found that when a pantograph slides on a steel core, the wear rate of a copper-coated steel trolley wire is reduced to about 1/10 that of a trolley wire made of copper or copper alloy.

Furthermore, with a trolley wire made of only copper or a copper alloy, the contact surface with the pantograph wears in a wavy shape,
A so-called disconnection phenomenon in which the pantograph is instantaneously separated from the trolley wire frequently occurs. Since an arc is generated when the pantograph is separated from the contact wire, such a disconnection phenomenon causes noise. However, in the case of a copper-coated steel trolley wire, it is known that when the steel core comes into contact with the pantograph, the contact surface with the pantograph becomes smooth and the wire separation phenomenon decreases.

As described above, the copper-coated steel trolley wire has various excellent advantages as compared with the trolley wire made of copper or copper alloy.

Conventionally, the copper-coated steel trolley wire is manufactured by the following method. That is, first, a copper-coated steel wire in which a coating layer made of copper or a copper alloy is concentrically arranged around a steel core is sequentially passed through a plurality of wire drawing dies to be thinned to a predetermined wire diameter. At the same time, as shown in FIG. 5, groove portions 28 extending in the length direction are formed on both sides of the upper half portion of the coating layer 27. This completes the copper-coated steel trolley wire.

[0007]

However, the above-mentioned conventional method for manufacturing a copper-coated steel trolley wire has the following problems. That is, in the copper-coated steel trolley wire manufactured by the conventional method, as shown in FIG. 5, since the steel core 26 that contributes to the improvement of the tensile strength and the wear resistance is at the center of the trolley wire, sliding friction by the pantograph is performed. As a result, a large amount of the copper or copper alloy in the portion below the steel core 26 is worn away in the initial stage until the steel core 26 is exposed. For this reason, the electrical conductivity of the trolley wire is significantly reduced until the steel core 26 is exposed. Further, since the thickness of the copper coating layer on the contact surface side with the pantograph is relatively large, the contact surface with the pantograph wears in a wavy shape, and an arc due to a disconnection phenomenon occurs. This disconnection phenomenon is reduced if the pantograph comes into contact with the steel core, but since it takes a long time before the steel core comes into contact with the pantograph, the conventional copper-coated steel trolley wire has a relatively long period of time. Disconnection phenomenon occurs.

The present invention has been made in view of the above problems, and has a good conductivity and a short time until the steel core is exposed due to sliding of the pantograph, resulting in a decrease in conductivity and a separation of the pantograph. An object of the present invention is to provide a method for producing a copper-coated steel trolley wire capable of producing a copper-coated steel trolley wire capable of suppressing a phenomenon.

[0009]

A method of manufacturing a copper-coated steel trolley wire according to the present invention comprises: drawing a copper-coated steel wire with a die having a protrusion protruding toward the center to form a coating layer A step of forming a deformed copper-coated steel wire that forms a recess in a part,
A forming step of forming the deformed copper-coated steel wire into a trolley wire shape in which the concave side corresponds to the large arc surface side and the coating layer on the large arc surface side is thin.

[0010]

In the present invention, first, a copper-coated steel wire having a coating layer made of copper or a copper alloy coated on the periphery of a steel core is used as a raw material, and the copper is coated with a die having a projecting portion projecting toward the center. The coated steel wire is drawn to obtain a deformed copper-coated steel wire having a recess in a part of the coating layer. In this modified copper-coated steel wire, the thickness of the coating layer around the steel core is non-uniform, and the thickness of the coating layer in the recessed portion is smaller than that in the other portions. Next, the deformed copper-coated steel wire is formed into a trolley wire shape such that the recess side is the large arc surface side (contact surface side with a pantograph or the like). This makes it possible to obtain a copper-coated steel trolley wire having a thin coating layer on the large arc surface side. In this case, since the deformed copper-coated steel wire is formed by wire drawing, it is possible to easily obtain the deformed copper-coated steel wire, and unlike the case where the deformed shape is formed by cutting or the like, copper or copper alloy coating is applied. The advantage is that layers are not truncated unnecessarily. In the copper-coated steel trolley wire manufactured in this way, the coating layer on the large arc surface side is thin, so the steel core is exposed in a short time from the start of use. Therefore, the amount of copper or copper alloy that is worn away by the time the steel core is exposed is small, and it is possible to suppress a decrease in conductivity, and it is also possible to suppress wavy wear and disconnection of the trolley wire. Further, according to the method of the present invention, since the copper or copper alloy coating layer on the small arc surface side of the trolley wire is inevitably thick, good conductivity is maintained.

[0011]

Embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 1 is a plan view showing a modified die used in the method of the present invention. The modified die 1 has a processed portion 2 that is substantially circular in a plan view, and a protruding portion 2a that protrudes toward the center in a mountain shape is provided in the lower portion of the processed portion 2.

In this embodiment, first, as a material,
A copper-coated steel wire in which a coating layer made of copper or a copper alloy is concentrically arranged around a steel core is prepared. Then, this copper-coated steel wire is passed through the odd-shaped die 1 shown in FIG. 1 and subjected to wire drawing (drawing). In this way, by passing the copper-coated steel wire having a circular cross-sectional shape through the odd-shaped die 1, it is possible to obtain an odd-shaped copper-coated steel wire having a cross-sectional shape that follows the shape of the processed portion 2 of the odd-shaped die 1.

FIG. 2 is a sectional view showing the deformed copper-coated steel wire 5 thus obtained. As shown in FIG. 2, in the deformed copper-coated steel wire 5 that has passed through the deformed die 1, the steel core 6 has a substantially circular cross-sectional shape, and a recess 8 is formed in a part of the copper coating layer 7. . That is, the thickness of the coating layer 7 around the steel core 6 is not uniform, and the coating layer 7 in the recess 8 portion is thinner than the coating layer 7 in other portions.

Next, the deformed copper-coated steel wire is sequentially drawn by using a plurality of dies having a predetermined shape, and the modified copper-coated steel wire is sequentially processed into a circular cross-sectional shape. In addition, at least at the final stage of the wire drawing process, as shown in FIG. 3, a die 10 having a substantially circular shape in the processed portion 12 and provided with protrusions 11 on both sides of the upper half thereof is arranged,
The protrusions 11 of the die 10 form a pair of groove portions that divide the peripheral surface into a large arc surface side and a small arc surface side on both sides of the upper half of the copper-coated steel wire. In this wire drawing process, the recess 8 side of the deformed copper-coated steel wire 5 is set to the large arc surface forming portion side 1 of each wire drawing die.
It is necessary to place in 3 and pass through the die. Then, as shown in FIG. 4, a copper-coated steel trolley wire having a substantially circular cross-section and having a pair of groove portions 18 dividing the peripheral surface into a small arc surface side 15a and a large arc surface side 15b is obtained. be able to. In this copper-coated steel trolley wire, the coating layer 17 on the large arc surface side (contact surface side with the pantograph) is thin, and the coating layer 17 on the small arc surface side is thick. The steel core 16 is the copper coating layer 17
It is pressed against the wall surface of the die through and has a substantially elliptical cross-sectional shape.

According to the method of this embodiment, a deformed copper-coated steel wire having a dent in a part of the coating layer is formed by drawing a copper-coated steel wire with a die having a protrusion protruding toward the center. Then, since the deformed copper-coated steel wire is further drawn to manufacture a trolley wire, it is possible to easily manufacture a copper-coated steel trolley wire having an extremely thin coating layer on the large arc surface side. Also,
The copper-coated steel trolley wire manufactured by the method of this example has good conductivity because the copper coating layer on the small arc side is thick. Furthermore, the copper-coated steel trolley wire produced by the method of this example has a thin coating layer on the large arc surface side, which is the contact surface side with the pantograph, so that the steel core is exposed by sliding the pantograph. It is possible to obtain the effects of improving the wear resistance and suppressing the wire separation phenomenon by the steel core in a relatively short time from the start of use, and the amount of the coating layer worn away before the steel core is exposed. Since the amount is small, the change in conductivity is small. Furthermore, in the present embodiment, the steel core is deformed into an elliptical shape having a major axis in the direction orthogonal to the contact surface with the pantograph, so that the effects such as the wear resistance improving effect and the wire separation phenomenon suppressing effect due to the steel core are long. It can be maintained for a period of time. When drawing a variant copper-coated steel wire, by pulling the variant copper-coated steel wire using a die provided with protrusions so as to compress the variant copper-coated steel wire from both sides, The core can be more surely deformed into an elliptical shape.

Next, the result of actually manufacturing a copper-coated steel trolley wire by the method of this embodiment and examining the thickness of the copper-coated layer will be described.

First, a copper-coated steel wire having a diameter of 17 mm was prepared as a raw material. The coating layer of this copper-coated steel wire has a thickness of about 3.10 mm. Next, this copper-coated steel wire was drawn by using a modified die having the shape shown in FIG. 1 to obtain a modified copper-coated steel wire 5 having the shape shown in FIG. The shape of the recess 8 of the copper coating layer of the modified copper-coated steel wire 5 is about 6 mm in width and about 2.5 mm in depth. The recess 8 of this deformed copper-coated steel wire 5
The thickness of the coating layer 7 in the portions other than is almost the same as that before the drawing process, and the thickness of the coating layer 7 in the recess 8 portion is about 0.5 mm.
It became about 1/6 of that before the drawing process.

Next, the deformed copper-coated steel wire is successively drawn through a plurality of drawing dies and a die provided with a projection for forming a groove, and the wire has a diameter of 12.34 mm.
A copper-coated steel wire trolley wire with a groove having the shape shown in Fig. 3 was obtained. In addition,
In this wire drawing step, the concave side of the deformed copper-coated steel wire was arranged on the large arc surface forming portion side of each die.

With respect to the copper-coated steel trolley wire (cross-sectional area: 110 mm ² ) thus manufactured, the dimensions of the steel core and the thickness of the copper coating layer were measured. As a result, the thickness of the copper coating layer on the large arc surface side (contact surface side with the pantograph) is 0.8 mm,
The thickness of the copper coating layer on the small arc surface side was 2.70 mm, and it was confirmed that the steel core was eccentric to the contact surface side with the pantograph. In the case of the copper-coated steel trolley wire (cross-sectional area: 110 mm ² ) manufactured by the conventional method, the thickness of the copper coating layer on both the large arc surface side and the small arc surface side is 2.1 mm. Further, the steel core of the copper-coated steel trolley wire manufactured by the method of this example is deformed into a substantially elliptical shape, and its height is 9 m.
m and the width was 6.4 mm.

[0021]

As described above, in the method of the present invention, first, the copper-coated steel wire is wire-drawn by a die having a protrusion protruding toward the center, and a modified shape having a recess in a part of the coating layer is formed. By forming a copper-coated steel wire and shaping this modified copper-coated steel wire into a trolley wire shape with a thin coating layer on the large arc surface side, a trolley wire whose steel core is eccentric to the contact surface side with the pantograph can be easily It can be manufactured. Therefore, the copper-coated steel trolley wire produced by the method of the present invention has good conductivity, and the time until the steel core is exposed is short, so that it is possible to suppress a decrease in conductivity and wavy wear.

[Brief description of drawings]

FIG. 1 is a plan view showing a modified die used in an embodiment method of the present invention.

FIG. 2 is a cross-sectional view showing a deformed copper-coated steel wire that has been drawn using a deformed die.

FIG. 3 is a plan view showing a drawing die.

FIG. 4 is a cross-sectional view showing a copper-coated steel trolley wire manufactured by the method of this example.

FIG. 5 is a cross-sectional view showing a conventional copper-coated steel trolley wire.

[Explanation of symbols]

 1; Deformed die 2, 12; Processed portion 2a; Protruded portion 5; Deformed copper coated steel wire 6, 16, 26; Steel core 7, 17, 27; Coating layer 8; Recess 10; Die 11; Protrusion 15a, 25a; Small arc side 15b, 25b; Large arc side 18, 28; Groove

Claims (1)

[Claims] 1. A step of forming a deformed copper-coated steel wire, which comprises drawing a copper-coated steel wire by a die having a protrusion protruding toward the center to form a recess in a part of the coating layer, A step of forming a deformed copper-coated steel wire into a trolley wire shape in which the coating layer on the large arc surface side is thin with the concave side corresponding to the large arc surface side. Method.