Die for trolley wire

Abstract

To provide a die for trolley wire which is used for drawing a trolley wire including a hole for abrasion detection line, in which breakage of a projection for forming the hole for abrasion detection line is suppressed, and which can be suitably used also for drawing a trolley wire for low tension section.SOLUTION: A die 2 for trolley wire used for drawing a body 10 of a trolley wire 1 having a hole 14 for abrasion detection line for accommodating an optical fiber 16 comprises a projection 21 which projects toward an inner side of a die hole 20, and forms a groove 140 to be processed in the hole 14 for abrasion detection line in a raw material of the body 10 of the trolley wire 1. The material has a Rockwell hardness of 85 HRA or more and a fracture toughness value of 15 MPa / m1 / 2 or more.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a trolley wire die used for drawing a trolley wire incorporating an optical fiber as a wear detection wire. [Background technology]

[0002] Conventionally, a technique for processing a trolley wire by wire drawing using a die has been known (see, for example, Patent Document 1). Patent Document 1 discloses that wire drawing using a die is preferable for processing long products such as trolley wires because of ease of handling, excellent dimensional stability, and the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-320413 A Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, a die for drawing a trolley wire having a wear detection wire hole for accommodating a wear detection wire is provided with a protrusion for forming the wear detection wire hole. In such a die, the mechanical strength of the protrusion is relatively low and is easily damaged by the force applied during the wire drawing of the trolley wire. In particular, the present inventors have confirmed that the protrusion portion is more easily damaged in a die in which the protrusion used for drawing a trolley wire for a low tension section is located at a higher position than in a die in which the protrusion used for drawing a trolley wire for a high tension section is located at a lower position.

[0005] The object of the present invention is to provide a trolley wire die used for drawing trolley wire having a hole for a wear detection wire, which reduces damage to the protrusions for forming the hole for the wear detection wire and can also be suitably used for drawing trolley wire for low tension sections. [Means for solving the problem]

[0006] The present invention aims to solve the above-mentioned problems by providing a trolley wire die used for drawing a trolley wire body having a wear detection wire hole for accommodating a wear detection wire, the die having a protrusion protruding toward the inside of the die hole for forming a groove to be machined into the wear detection wire hole in the material of the trolley wire body, the material having a Rockwell hardness of 85 HRA or more and a fracture toughness value of 15 MPa / m 1 / 2 As described above, a contact wire die is provided. Effect of the Invention

[0007] According to the present invention, a trolley wire die can be provided that is used for drawing a trolley wire having a hole for a wear detection wire, which reduces damage to the protrusions for forming the hole for the wear detection wire and can also be suitably used for drawing a trolley wire for a low tension section. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a radial cross-sectional view of an example of a trolley wire formed by wire drawing using a trolley wire die according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing how a metal wire is drawn using a contact wire die. [Diagram 3] 3(a) to (e) are diagrams showing examples of changes in the cross-sectional shape of a metal wire during the wire drawing process. [Figure 4] 4(a) and (b) are radial cross-sectional views of the metal wire and the contact wire body, respectively. [Diagram 5] 5(a) and (b) are schematic diagrams showing the shapes of the die holes on the outlet side of a contact wire die and a deformed wire drawing die, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A trolley wire die according to an embodiment of the present invention is a die used for drawing a trolley wire having a wear detection wire hole for accommodating a wear detection wire, the die having a protrusion protruding toward the inside of the die hole for forming a groove to be machined into the wear detection wire hole in a material of the trolley wire body, and the material has a Rockwell hardness of 85 HRA or more and a fracture toughness value of 15 MPa / m 1 / 2 The above is the trolley wire die. Hereinafter, the details of the trolley wire die according to the embodiment of the present invention will be described.

[0010] (Contact Wire Structure) 1 is a radial cross-sectional view of a trolley wire 1, which is an example of a trolley wire formed by wire drawing using a trolley wire die according to an embodiment of the present invention. The trolley wire 1 has a trolley wire body 10 having two wear detection wire holes 14 therein, and two optical fibers 16 as wear detection wires housed in the two wear detection wire holes 14. The trolley wire 1 has a length according to the distance of the overhead line section of the track, and is, for example, 500 m or more and 1850 m or less.

[0011] The trolley wire body 10 of the trolley wire 1 is an irregular round trolley wire having V-shaped ear grooves 13 on both sides, a large arc surface 12 below the ear grooves 13, and a linear wear detection wire hole 14 provided along the longitudinal direction of the trolley wire body 10 at a predetermined distance from the bottom of the large arc surface 12. The trolley wire body 10 corresponds to a grooved hard copper trolley wire specified in JISE2101 and IEC62917.

[0012] The nominal cross-sectional area of ​​the contact wire body 10 is 170 mm 2 (170SQ) or less. Here, the nominal cross-sectional area is 170 mm 2 This means that the calculated cross-sectional area is about 170 mm when it is assumed that the wear detection line hole 14 is not provided. 2 (For example, 169.4 mm 2 More than 172.2mm 2 (see below).

[0013] The trolley wire body 10 is mainly composed of a copper alloy, for example, a Cu-Sn-In based alloy or a Cu-Sn based alloy.

[0014] When power is supplied to an electric train through the trolley wire 1, the bottom of the large arc surface 12 of the trolley wire body 10 comes into contact with the electric train's current collector, such as a pantograph. As a result, the sliding of the current collector causes the trolley wire body 10 to wear from the bottom of the large arc surface 12. When the wear of the trolley wire body 10 progresses and the optical fiber 16 breaks, the breakage detection system is activated and detects that the trolley wire body 10 has worn down to near its limit of use.

[0015] The trolley wire body 10 is provided with two wear detection wire holes 14, one on each side of the center line 15 of the trolley wire body 10, and each of the two wear detection wire holes 14 houses an optical fiber 16. By using the two optical fibers 16, wear can be detected even when uneven wear occurs.

[0016] The diameter of the optical fiber 16 is, for example, 0.9 mm or more and 1.1 mm or less. An optical fiber 16 having a diameter smaller than 1.1 mm can be obtained, for example, by thinning the outer coating of an optical fiber having a diameter of 1.1 mm that is commonly used in the past. Note that, instead of the optical fiber 16, a wear detection wire other than the optical fiber 16, such as an insulated electric wire, may be used.

[0017] Generally, in a section where the contact wire is strung at low tension (called a low tension section), the tension applied to the contact wire is low, so that the contact wire can withstand use even with a small cross-sectional area. Therefore, the contact wire strung in the low tension section has a higher tolerance for the reduction in cross-sectional area due to wear compared to the contact wire strung in the high tension section (the section where the contact wire is strung at high tension), and the wear detection wire is accommodated at a higher position.

[0018] (Contact wire drawing) The trolley wire 1 is processed into a trolley wire body 10 by wire drawing using a trolley wire die, and in the process, an optical fiber 16 is accommodated in a wear detection wire hole 14 in the trolley wire body 10. Hereinafter, the linear metal that is the material of the trolley wire body 10 and is processed into the trolley wire body 10 by wire drawing will be referred to as a metal wire 100.

[0019] Fig. 2 is a schematic diagram showing how a metal wire 100 is drawn using a trolley wire die 2. As shown in Fig. 2, when the metal wire 100 is inserted into a die hole 20 from the entrance side S1 (die entrance) of the trolley wire die 2 and pulled out from the exit side S2 (die exit) of the trolley wire die 2, the metal wire 100 is processed into a shape corresponding to the shape of the die hole 20. The cross-sectional shape of the metal wire 100 pulled out from the trolley wire die 2 becomes the same as the shape of the die hole 20 at the exit side S2 of the trolley wire die 2.

[0020] Figures 3(a) to (e) are diagrams showing examples of changes in the cross-sectional shape of a metal wire 100 during the wiredrawing process. The metal wire 100 in the states shown in Figures 3(a) to (d) are referred to as metal wires 100a to 100d, respectively. The metal wire 100 in the state shown in Figure 3(e) corresponds to the trolley wire body 10. Hereinafter, an example of the flow of the wiredrawing process will be described with reference to Figures 3(a) to (e).

[0021] The metal wire 100a shown in Fig. 3(a) is a metal wire 100 having a circular cross section in the radial direction. First, the metal wire 100a is drawn using a wire drawing die to reduce the diameter, thereby obtaining the metal wire 100b shown in Fig. 3(b).

[0022] Next, the metal wire 100b is passed through a peeling die to remove the outermost layer 101, thereby obtaining a metal wire 100c with improved surface smoothness as shown in FIG. 3(c).

[0023] Next, the metal wire 100c is drawn using a trolley wire die 2, which is a special-shaped wire drawing die, to obtain a metal wire 100d shown in Fig. 3(d). The metal wire 100d corresponds to the trolley wire body 10 before accommodating the optical fiber 16, and has a groove 140 for forming the wear detection wire hole 14. In this process, the diameter of the metal wire 100 is reduced and the cross-sectional shape is changed.

[0024] Next, the metal wire 100d is drawn using a special-shaped wire drawing die 3 described later, whereby the groove 140 is processed into the wear detection wire hole 14, and the trolley wire body 10 shown in Fig. 3(e) is obtained. In this process, before the metal wire 100 is passed through the special-shaped wire drawing die 3, the optical fiber 16 is placed in the groove 140 of the metal wire 100d. As a result, when the opening of the groove 140 is closed by drawing using the special-shaped wire drawing die 3, the wear detection wire hole 14 in which the optical fiber 16 is accommodated is formed.

[0025] 4(a) and 4(b) are radial cross-sectional views of the metal wire 100d and the trolley wire body 10, respectively. Also, Fig. 5(a) and 5(b) are schematic diagrams showing the shapes of the die holes 20 and 30 on the outlet side of the trolley wire die 2 for processing the metal wire 100c into the metal wire 100d and the special wire drawing die 3 for processing the metal wire 100d into the trolley wire body 10, respectively.

[0026] The shape of the die hole 20 at the exit side S2 of the trolley wire die 2 corresponds to the radial cross-sectional shape of the metal wire 100d. Also, the shape of the die hole 30 at the exit side of the deformed wire drawing die 3 corresponds to the radial cross-sectional shape of the trolley wire body 10.

[0027] For example, the shapes of the die exit side of the portion 202 of the die hole 20 and the portion 302 of the die hole 30 correspond to the shapes of the metal wire 100d and the ear groove 13 of the trolley wire body 10. Moreover, the shape of the die exit side of the portion 303 of the die hole 30 corresponds to the shape of the large arc surface 12 of the trolley wire body 10.

[0028] The height of the die hole 30 at the exit side of the deformed wire drawing die 3 is set to 170 mm 2The height of the contact wire body 10 is equal to that of the contact wire body 10 and is approximately 15.49 mm (for example, not less than 15.34 mm and not more than 15.64 mm).

[0029] The protrusion 21 protruding toward the inside of the die hole 20 of the trolley wire die 2 is for forming a groove 140 for the metal wire 100d. The protrusion 21 is, for example, a linear protrusion 21 provided on a part of the exit side S2 of the trolley wire die 2, and its height h2 (maximum value of the height from the base to the apex of the protrusion 21) and width W increase from the entrance side S1 to the exit side S2. The shape of the protrusion 21 on the exit side S2 of the trolley wire die 2 corresponds to the cross-sectional shape of the groove 140. The edge 141 of the opening of the groove 140 formed by wire drawing using the trolley wire die 2 is closed by wire drawing using the deformed wire drawing die 3, thereby forming the wear detection wire hole 14. The height h1 of the protrusion 21 from the bottom of the die hole 20 on the exit side S2 (die exit) of the trolley wire die 2 is, for example, 8.95 mm or less.

[0030] As described above, in general, a trolley wire that is suspended in a low tension section has a larger tolerance for a reduction in cross-sectional area due to wear than a trolley wire that is suspended in a high tension section, and the wear detection wire is accommodated at a higher position. For this reason, when the trolley wire 1 is suspended in a low tension section, the wear detection wire hole 14 of the trolley wire body 10 is provided at a relatively high position. In order to provide the wear detection wire hole 14 of the trolley wire body 10 at a high position, it is necessary to provide the protrusion 21 of the trolley wire die 2 at a high position.

[0031] If the projections 21 are damaged, the trolley wire die 2 cannot be used. Specifically, if fine scratches are found during die maintenance, they can be repaired by polishing, but if irreparable damage, such as breakage of the projections 21, is found, the trolley wire die 2 is discarded.

[0032] Contact wire die 2 has a Rockwell hardness of 85HRA or more and a fracture toughness of 15MPa / m 1 / 2The die 2 is made of the above material, for example, a cemented carbide such as a WC-Co alloy. Therefore, even if the protrusions 21 are provided at a high position to manufacture the trolley wire 1 for a low tension section, damage to the protrusions 21 during wire drawing can be suppressed. Also, even if the protrusions 21 are provided at a low position, the durability of the protrusions 21 can be improved, and the life of the trolley wire die 2 can be extended.

[0033] (Durability test of contact wire dies) The following describes the contents and results of the durability test of the trolley wire dies 2. In this test, three trolley wire dies 2 (specimens A, B, and C) made of different materials and properties were prepared as samples.

[0034] Specimens A, B, and C all have a nominal cross-sectional area of ​​170 mm 2 This is a special-shaped wire drawing die for forming a contact wire body 10 for a low tension section, and has a die hole 20 of the same shape.

[0035] Using samples A, B, and C, metal wire 100 made of a Cu-Sn-In alloy was drawn twice for each. In the first drawing, the metal wire 100 was drawn to about 1600 m, and in the second drawing, the metal wire 100 was drawn to about 1000 m. After these two drawing cycles, the samples that were still in a usable state were classified as passed, and those that were not in a usable state were classified as failed. The following Table 1 shows the materials, properties (Rockwell hardness and fracture toughness value), and test results of samples A to C.

[0036] [Table 1]

[0037] The protrusion 21 of sample A broke during the second drawing, and the sample A was rejected. The alloy tool steel from which sample A was made is a commonly used material for wire drawing dies, and the fracture toughness value is unknown. However, the fracture toughness value of sample B was 9.7 MPa / m 1 / 2 I know it's bigger than that.

[0038] In the case of sample B, the projection 21 broke during the first drawing, and the sample B was rejected. Compared with sample C, which passed, the reason for the rejection is believed to be that the fracture toughness value was insufficient.

[0039] Of the three specimens A, B, and C, only specimen C passed the test. The Rockwell hardness was 85 HRA and the toughness was 15 MPa / m 1 / 2 The WC-Co alloy used in sample C has a Rockwell hardness of 88 HRA and a toughness of 18 MPa / m 1 / 2 It has been confirmed that it has the same strength as WC-Co alloys. This means that it has a Rockwell hardness of 85 HRA or more and a toughness of 15 MPa / m 1 / 2 It is estimated that a contact wire die 2 made of the above-mentioned materials will have the same performance as sample C.

[0040] (Effects of the embodiment) According to the above-described embodiment of the present invention, it is possible to provide a trolley wire die 2 used for drawing a trolley wire 1 having a wear detection wire hole 14, which suppresses damage to the protrusions 21 for forming the grooves 140 to be machined in the wear detection wire hole 14 in the metal wire 100, and can be suitably used for drawing a trolley wire 1 for a low tension section. Specifically, for example, even if the protrusions 21 are provided at a high position for use in drawing a trolley wire 1 for a low tension section, the trolley wire die 2 can be used for multiple drawing operations.

[0041] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiment will be described by using the reference numerals and the like in the embodiment. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiment.

[0042] [1] A trolley wire die used for drawing a main body (10) of a trolley wire (1) having a wear detection wire hole (14) for accommodating a wear detection wire (16), the die having a protrusion (21) protruding toward the inside of the die hole (20) for forming a groove (140) to be machined in the wear detection wire hole (14) in the material of the main body (10) of the trolley wire (1), the material having a Rockwell hardness of 85 HRA or more and a fracture toughness value of 15 MPa / m 1 / 2 That’s it for the contact wire die (2).

[0043] [2] The contact wire die (2) according to the above [1], wherein the material is a cemented carbide.

[0044] [3] The Rockwell hardness of the material is 88HRA or more, and the toughness value is 18MPa / m 1 / 2 The above is the above-mentioned contact wire die (2) according to [1] or [2].

[0045] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit and scope of the invention.

[0046] In addition, the above-described embodiments do not limit the scope of the invention according to the claims. Also, it should be noted that not all of the combinations of features described in the embodiments are essential to the means for solving the problems of the invention. [Explanation of symbols]

[0047] 1 Contact wire 10 Contact wire body 14 Hole for wear detection line 140 Groove 16 Optical Fiber 2 Contact wire dies 20 Die Hole 21 Protrusion

Claims

1. A trolley wire die used for drawing a trolley wire body having a wear detection wire hole for accommodating a wear detection wire, A protrusion is provided in the die hole for forming a groove in the material of the main body of the trolley wire, the groove being machined into the wear detection wire hole, the protrusion protruding toward the inside of the die hole; The material has a Rockwell hardness of 85 HRA or more and a fracture toughness of 15 MPa / m １／２ That's all. Dies for contact wire.

2. The material is a cemented carbide; 2. The contact wire die according to claim 1.

3. The material has a Rockwell hardness of 88 HRA or more and a toughness value of 18 MPa / m １／２ That's all.

3. A contact wire die according to claim 1 or 2.

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