Cable

Abstract

To provide a cable that may readily perform identification of wires.SOLUTION: Cable 1 is composed of an aggregate 3 of multiple wires 2 that are twisted together in two or more layers, which can be identified by the appearance of the insulator 22, and a sheath 5 that covers the periphery of the aggregate 3. Among the aggregate 3, the multiple wires 2 that make up the inner layer 3a, which is the inner layer in the cable diameter direction, and the multiple wires 2 that make up the outer layer 3b, which is the outer layer compared to the inner layer 3a in the cable diameter direction, are configured to be able to identify the wire 2 using different identification methods.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a cable.

Background Art

[0002] In recent years, in devices such as industrial robots, the number of electric wires used has been increasing in order to cope with the complication of the devices and the high speed of signals. Therefore, in the cables used in devices such as industrial robots, the number of electric wires included in one cable tends to increase. In such a cable including a large number of electric wires, it is desired that each of the electric wires included in the cable can be easily identified in order to smoothly perform the terminal processing of the cable.

[0003] Patent Document 1 discloses that, at the time of terminal processing of a cable, an electric wire is identified by using the color of the insulator of the electric wire (for example, red, white, black, green) or an identification display such as a dot mark.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when using the method of Patent Document 1, since there are limitations in the colors and dot patterns for identification displays, there is a possibility that identification becomes difficult when the number of electric wires to be identified increases. As described above, in the cables used in devices such as industrial robots, the number of electric wires included in one cable has been increasing, and in some cases, a large number of electric wires, for example, dozens or more, are twisted together in multiple layers. Therefore, even when the number of electric wires is large, it is required to be able to easily identify the electric wires.

[0006] Therefore, an object of the present invention is to provide a cable capable of easily identifying electric wires.

Means for Solving the Problems

[0007] The present invention aims to solve the above problems, and includes an aggregate in which a plurality of electric wires configured to be distinguishable by the appearance of the insulator are twisted together in two or more layers, and a sheath covering the periphery of the aggregate. Among the aggregates, the plurality of electric wires constituting the inner layer, which is the inner layer in the cable radial direction, and the plurality of electric wires constituting the outer layer, which is the outer layer in the cable radial direction with respect to the inner layer, are configured to be able to identify the electric wires using different identification methods respectively. The present invention provides a cable.

[0008] Further, the present invention aims to solve the above problems, and includes an aggregate in which a plurality of electric wires configured to be distinguishable by the appearance of the insulator are twisted together in two or more layers, and a sheath covering the periphery of the aggregate. The plurality of electric wires include a plurality of pair-twisted wires obtained by twisting a pair of insulated electric wires together, and a plurality of insulated electric wires. The plurality of pair-twisted wires and the plurality of insulated electric wires are configured to be able to be identified using different identification methods respectively. The present invention provides a cable.

Advantages of the Invention

[0009] According to the present invention, a cable capable of easily identifying electric wires can be provided.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Best Mode for Carrying Out the Invention

[0011] [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0012] (Overall Structure of Cable 1) FIG. 1 is a cross-sectional view showing a cross-section perpendicular to the longitudinal direction of cable 1 according to this embodiment. Cable 1 is used, for example, in devices such as industrial robots. Cable 1 may be wired to a movable part to which operations such as repeated bending and twisting are applied. Note that the present invention is not limited to this, and cable 1 may be used as wiring for automobiles that are repeatedly swung (for example, wiring that connects a device provided on the vehicle body and a device provided on the wheel). Further, cable 1 can be used, for example, as wiring for medical equipment or wiring to a location that touches a person's skin.

[0013] Cable 1 includes an aggregate 3 in which a plurality of electric wires 2 are twisted together, and a sheath 5 that covers the periphery of the aggregate 3. In this embodiment, a holding tape 4 is provided around the aggregate 3, and the sheath 5 is provided so as to cover the periphery of the holding tape 4. Although not shown, a shield layer made of a braided shield or the like may be provided between the holding tape 4 and the sheath 5.

[0014] In the aggregate 3, a plurality of electric wires 2 are twisted together in two or more layers. Here, the aggregate 3 has a two-layer structure, but the aggregate 3 may have a layer structure of three or more layers. Hereinafter, among the layers constituting the aggregate 3, the inner layer in the cable radial direction is referred to as the inner layer 3a, and the layer outside the inner layer 3a in the cable radial direction is referred to as the outer layer 3b.

[0015] The wire 2 is composed of an insulated wire having a conductor 21 and an insulator 22 covering the periphery of the conductor 21. The conductor 21 is formed by twisting together a plurality of metal strands made of copper, a copper alloy, aluminum, or an aluminum alloy. The surface of the metal strand may be plated with tin, silver, or the like. The insulator 22 is made of polyolefin. Here, an insulator 22 made of PP (polypropylene) is used. The insulator 22 is preferably colored by adding an appropriate coloring agent. In the present embodiment, all the wires 2 constituting the inner layer 3a and the outer layer 3b have the same configuration, but the present invention is not limited to this, and wires 2 having different outer diameters and conductor cross-sectional areas may be included. Further, the wire 2 may include a coaxial wire, a multi-core wire in which a plurality of conductors 21 are collectively covered with an insulator 22, a pair-twisted wire in which a pair of insulated wires are twisted together, or the like.

[0016] The aggregate 3 has an intervening member 6 disposed at the center of the cable. Here, a fibrous intervening member 6 is used, but the present invention is not limited to this, and the intervening member 6 may be, for example, a linear body, a tube, or the like. The inner layer 3a is formed by helically twisting nine wires 2 around the intervening member 6. Note that the number of wires 2 constituting the inner layer 3a is not limited to the illustrated example. Hereinafter, the wire 2 constituting the inner layer 3a is referred to as an inner layer wire (first wire) 2a.

[0017] The outer layer 3b is formed by helically twisting fifteen wires 2 around the inner layer 3a. Note that the number of wires 2 constituting the outer layer 3b is not limited to the illustrated example. Hereinafter, the wire 2 constituting the outer layer 3b is referred to as an outer layer wire (second wire) 2b. Although not shown, a shield layer, a press wrap tape, or the like may be provided between the inner layer 3a and the outer layer 3b.

[0018] The press wrap tape 4 is for holding the aggregate 3 so that the twist does not unwind, and is made of a tape member such as a non-woven fabric tape, a resin tape, or a paper tape. The press wrap tape 4 is formed by spirally winding the tape member around the outer layer 3b such that a part in the width direction overlaps.

[0019] The sheath 5 is for protecting the assembly 3 and is made of, for example, a resin composition mainly composed of PVC (polyvinyl chloride), silicone rubber, chlorinated polyethylene, etc. When used for applications requiring chemical resistance or applications in contact with human skin, it is advisable to use a resin composition mainly composed of silicone rubber. The resin composition may contain additives such as crosslinking agents, crosslinking catalysts, antioxidants, plasticizers, lubricants, fillers, flame retardants, stabilizers, colorants, etc. Further, a film for improving the slipperiness of the surface of the sheath 9 may be provided to cover the surface of the sheath 9. In particular, when the sheath 9 is made of a resin composition mainly composed of silicone rubber, it is advisable to provide a film for improving the slipperiness on its surface. The film provided on the surface of the sheath 9 can be, for example, one formed by curing a liquid silicone rubber containing fine particles with an average particle diameter of 1 μm or more and 10 μm or less by an addition reaction. The fine particles are made of, for example, silicone rubber, silicone resin, etc. The thickness of the film is, for example, 3 μm or more and 100 μm or less. The static friction coefficient of the surface of the film is 0.5 or less. Also, the sheath 9 is preferably separated from the underlying member by a minute gap or the like. Thereby, rubbing can be prevented from occurring between the sheath 9 and the underlying member due to operations such as bending, and deterioration of the sheath 9 can be suppressed. The sheath 5 is formed by extrusion molding so as to cover the periphery of the holding tape 4.

[0020] (Identification method of the electric wire 2) In the cable 1 according to the present embodiment, the plurality of inner-layer electric wires 2a constituting the inner layer 3a and the plurality of outer-layer electric wires 2b constituting the outer layer 3b are configured to be able to identify the electric wires 2 using different identification methods. By making the identification methods different between the inner layer 3a and the outer layer 3b, compared with the case where the same identification method is used for all layers, it becomes possible to easily identify the inner-layer electric wires 2a and the outer-layer electric wires 2b from a large number of electric wires 2, such as dozens or more (for example, 20 or more). Also, when identifying a large number of electric wires 2 using a device such as an industrial robot, the device can easily identify the inner-layer electric wires 2a and the outer-layer electric wires 2b. Here, the identification of the electric wires 2 means that an operator or a device distinguishes each individual electric wire 2 and specifies the connection destination to a connector or the like (that is, for what purpose the electric wire 2 is). Also, the identification method, in other words, the identification method, means a specific method for identifying the electric wire 2.

[0021] In addition, when the aggregate 3 has a layer structure of three or more layers, for example, the identification methods may be different for each layer, or three or more identification methods may be used. However, since there is a risk of confusion during identification when the number of identification methods increases, it is not preferable to increase the number of identification methods too much. For example, when identifying about 60 to 100 electric wires 2, it is possible to easily identify them with two identification methods. That is, in the cable 1, it is possible to identify a large number of twisted electric wires 2 with two or more layers while keeping the number of types of identification methods small. Examples of the identification method include identification by the color of the insulator 22, identification by an identification pattern such as a dot pattern obtained by printing a dot mark on the outer surface of the electric wire 2 according to a predetermined rule, identification by the color of the identification pattern, and the like. Here, the identification pattern refers to a pattern formed by printing or the like so that identification marks having a specific shape or structure are arranged along the longitudinal direction of the electric wire 2 according to a predetermined rule. The identification mark is not limited to a dot mark, and may be a character, a figure such as a polygon, a line such as a slanted line, a symbol or mark such as an arrow, a barcode, or the like. However, when applying to an electric wire 2 with a very small outer diameter, it can be said that it is desirable to use a simple dot mark that is easy for an operator to visually recognize.

[0022] More specifically, in the present embodiment, the plurality of inner-layer electric wires 2a that constitute the inner layer 3a are configured such that the electric wires 2 can be identified by the difference in the color of the insulator 22. The plurality of outer-layer electric wires 2b that constitute the outer layer 3b have an identification pattern printed on their outer surfaces along the longitudinal direction of the cable, and the electric wires 2 can be identified by the identification pattern. Generally, there are not so many variations in the color of the insulator 22, and increasing the variations in the color of the insulator 22 also leads to an increase in material costs and manufacturing costs. Therefore, in the present embodiment, in the inner layer 3a where the number of electric wires 2 is relatively small, identification by the color of the insulator 22 is used. And in the outer layer 3b where the number of electric wires 2 is relatively large, it can be said that it is desirable to use identification by an identification pattern that can identify many electric wires 2 by simply increasing the number of printed identification patterns.

[0023] As described above, since there are not so many variations in the color of the insulator 22, when the aggregate 3 has a layer structure of three or more layers, it is desirable to use only the innermost layer in the cable radial direction as the inner layer 3a and treat all other layers as the outer layer 3b. That is, when the aggregate 3 has a layer structure of three or more layers, it is desirable to perform identification by the color of the insulator 22 only in the innermost layer in the cable radial direction, and use identification by an identification pattern in other layers. Thereby, a large number of electric wires 2 twisted together in three or more layers can be identified while suppressing the number of types of identification methods.

[0024] (Identification of the electric wire 2 in the inner layer 3a) In this embodiment, the plurality of inner-layer electric wires 2a that constitute the inner layer 3a are configured such that their insulators 22 have different colors. As the colors of the insulators 22 that constitute the inner-layer electric wires 2a, for example, achromatic colors such as black, gray, and white, and chromatic colors such as brown, red, orange, yellow, green, blue, and purple can be used. Thereby, it becomes possible to identify the inner-layer electric wires 2a by the colors of the insulators 22. Note that the insulators 22 of the inner-layer electric wires 2a may be colored with two or more colors. For example, as shown in FIG. 2, a linear colored portion 22a may be provided along the longitudinal direction of the inner-layer electric wire 2a, and the inner-layer electric wire 2a may be identified by a combination of the base color of the insulator 22 and the color of the colored portion 22a. As a method for forming the colored portion 22a, for example, a linear extrusion method can be used in which a resin of a color different from the base color of the insulator 22 is continuously pushed in during extrusion molding to form the colored portion 22a along the longitudinal direction of the electric wire 2.

[0025] In the illustrated example, the ratio of the length of the colored portion 22a (the length of the colored portion 22a on the outer peripheral surface, or the total length if there are two or more colored portions 22a) to the total circumference (the length of the entire outer peripheral surface) of the electric wire 2 in a cross-sectional view is set to 30% or more and 40% or less. This is because if the length of the colored portion 22a is greater than the total circumference of the electric wire 2, it becomes difficult to distinguish whether it is the color of the colored portion 22a or the color of the insulator 22. Note that the insulator 22 is made of polyolefin (PP) and is formed by tube extrusion. In the example of FIG. 2, two colored portions 22a are formed, but the present invention is not limited to this, and the colored portion 22a may be provided at one location.

[0026] (Identification of the electric wire 2 in the outer layer 3b) In the outer layer 3b, identification is performed using an identification pattern. In this embodiment, as shown in FIG. 3, as the identification pattern, dot marks each having a quadrangular shape are arranged on the outer peripheral surface of each of the outer-layer electric wires 2b along the longitudinal direction of the cable according to a predetermined rule (for example, dot marks each having a quadrangular shape are continuously arranged at regular intervals), and the outer-layer electric wires 2b are identified by a dot pattern applied by printing or the like.

[0027] The identification of the outer layer wires 2b in the outer layer 3b can be carried out not only by an identification pattern (dot pattern), but also by combining the color of the insulator 22 and the color of the identification pattern (dot pattern). That is, the plurality of outer layer wires 2b constituting the outer layer 3b may be configured to be identifiable by a combination of an identification pattern attached to its outer surface by printing or the like, the color of the insulator 22, and the color of the identification pattern. Thereby, a larger number of outer layer wires 2b can be easily identified. In order to make the identification pattern (dot pattern) easily visible, it is desirable to determine the combination of the color of the insulator 22 constituting the outer layer wire 2b and the color of the identification pattern. Therefore, at least the color of the insulator 22 constituting the outer layer wire 2b and the color of the identification pattern need to be different. The color of the identification pattern is preferably a color that is easily visible, such as black or red, and preferably black. Also, as the color of the insulator 22, for example, white, yellow, orange, gray, etc., a color that makes the identification pattern easily visible may be selected, and preferably a non - black color.

[0028] (Actions and Effects of the Embodiment) As described above, in the cable 1 according to the present embodiment, the plurality of wires 2 (inner layer wires 2a) constituting the inner layer 3a of the aggregate 3 and the plurality of wires 2 (outer layer wires 2b) constituting the outer layer 3b are configured to be able to identify the wires 2 using different identification methods respectively. Thereby, even if the number of wires 2 included in the cable 1 is large, it becomes possible to easily identify the wires 2.

[0029] In particular, when the outer diameter of the wire 2 becomes as thin as 2.0 mm or less, it becomes even more difficult to identify the wire 2. However, by identifying the inner layer wire 2a by the color of the insulator 22 and the outer layer wire 2b by the identification pattern, it is possible to easily identify the wire 2. By facilitating the identification of the wire 2, it becomes possible to easily perform the work during terminal processing when connecting the cable 1 to a connector or the like, and the workability of terminal processing is improved. Furthermore, since the identification of each wire 2 becomes easy, the manufacture of the cable 1 also becomes easy.

[0030] (Other Embodiments) FIG. 4 is a cross-sectional view showing a cross-section perpendicular to the longitudinal direction of the cable 1a according to another embodiment of the present invention. As shown in FIG. 4, in the cable 1a, the electric wires 2 constituting the assembly 3 include a plurality of signal lines 2c each formed of a pair of twisted insulated wires 23, and a plurality of power lines 2d each formed of an insulated wire.

[0031] The insulated wire 23 constituting the signal line 2c has a conductor 23a and an insulator 23b covering the periphery of the conductor 23a, respectively. Further, the insulated wire 24 constituting the power line 2d has a conductor 24a and an insulator 24b covering the periphery of the conductor 24a, respectively. The conductors 23a and 24a are formed of a stranded conductor obtained by stranding metal strands made of copper or a copper alloy. The surface of the metal strand may be plated with tin, silver, or the like. The insulator 23b of the insulated wire 23 constituting the signal line 2c (twisted pair) is made of a fluororesin, TPE (thermoplastic elastomer), nylon, or the like. Here, a fluororesin is used as the insulator 23b. The insulator 24b of the insulated wire 24 constituting the power line 2d is made of a polyolefin (PP here).

[0032] In the cable 1a, an inner layer 3a is formed by twisting eight signal lines 2c around an intervening member 6 made of a resinous linear body having a circular cross-section. Then, a tape member 7 such as a resin tape is wound around the inner layer 3a in a spiral manner (such that a part in its width direction overlaps), and a shield layer 8 made of a braided shield or the like is provided around it. Then, an outer layer 3b is formed by twisting three signal lines 2c and twelve power lines 2d around the shield layer 8. A press winding tape 4 and a sheath 5 are sequentially provided around the outer layer 3b.

[0033] Note that the signal lines 2c arranged in the inner layer 3a transmit high-speed signals and are greatly affected by noise, and the signal lines 2c arranged in the outer layer 3b transmit low-speed signals with little influence of noise such as control signals. By arranging a part of the signal lines 2c in the outer layer 3b, it contributes to reducing the diameter of the cable 1a.

[0034] In this embodiment, a plurality of signal lines 2c and a plurality of power lines 2d are configured to be distinguishable using different identification methods. More specifically, the plurality of signal lines 2c are configured such that the combinations of the colors of the insulators 23b of a pair of insulated wires 23 forming a twisted pair are different from each other, and the signal lines 2c can be identified by the combinations of the colors of the insulators 23b of the pair of insulated wires 23. And the plurality of power lines 2d can be identified by an identification pattern. That is, an identification pattern is attached to the outer surfaces of the plurality of power lines 2d by printing or the like along the longitudinal direction of the cable, and the power lines 2d can be identified by the identification pattern. Note that, as the colors of the insulators 23b forming the pair of insulated wires 23, for example, achromatic colors such as black, gray, and white, and chromatic colors such as brown, red, orange, yellow, green, blue, and purple can be used. Also, as the color of the insulator 24b forming the insulated wire 24, for example, colors such as white, yellow, orange, and gray, which are easy to visually recognize the identification pattern, are preferably selected, and non-black colors are preferable. Also, the color of the identification pattern attached to the insulator 24b is preferably a color that is easy to visually recognize, such as black or red, and preferably black. The color of the insulator 24b forming the insulated wire 24 and the color of the identification pattern are preferably different from each other.

[0035] As described above, when a part of the signal lines 2c is disposed in the outer layer 3b, the identification methods of the signal lines 2c and the power lines 2d are preferably made different. Thereby, the signal lines 2c and the power lines 2d can be easily identified from among a large number of wires 2 twisted in two or more layers. In particular, when the signal lines 2c are formed of twisted pairs, more signal lines 2c can be identified by making them distinguishable by the combinations of the colors of the insulators 23b of the pair of insulated wires 23.

[0036] (Summary of the Embodiment) Next, the technical idea grasped from the embodiments described above will be described by referring to the reference numerals and the like in the embodiments. However, each reference numeral and the like in the following description are not limited to the members and the like that specifically show the components in the claims in the embodiments.

[0037] [1]A cable (1) comprising an aggregate (3) in which a plurality of electric wires (2) configured to be distinguishable by the appearance of the insulator (22) are twisted together in two or more layers, and a sheath (5) covering the periphery of the aggregate (3), wherein among the plurality of electric wires (2) constituting the aggregate (3), the plurality of electric wires (2) constituting the inner layer (3a) which is the inner layer in the cable radial direction and the plurality of electric wires (2) constituting the outer layer (3b) which is the layer outside the inner layer (3a) in the cable radial direction are configured to be distinguishable from the electric wires (2) by using different identification methods respectively.

[0038] [2]The plurality of electric wires (2) constituting the inner layer (3a) are configured to be distinguishable from the electric wires (2) by the difference in the color of the insulator (22), and the plurality of electric wires (2) constituting the outer layer (3b) have an identification pattern printed on their outer surfaces along the cable longitudinal direction, and are configured to be distinguishable from the electric wires (2) by the identification pattern. The cable (1) according to [1].

[0039] [3]The plurality of electric wires (2) constituting the outer layer (3b) are configured to be distinguishable from the electric wires (2) by the combination of the identification pattern printed on their outer surfaces, the color of the insulator (22), and the color of the identification pattern. The cable (1) according to [2].

[0040] [4]A cable (1a) comprising an aggregate (3) in which a plurality of electric wires (2) configured to be distinguishable by the appearance of the insulator (22) are twisted together in two or more layers, and a sheath (5) covering the periphery of the aggregate (3), wherein the plurality of electric wires (2) include a plurality of pair-twisted wires (signal wires 2c) obtained by twisting a pair of insulated electric wires (23) together and a plurality of insulated electric wires (power supply wires 2d), and the plurality of pair-twisted wires (signal wires 2c) and the plurality of insulated electric wires (power supply wires 2d) are configured to be distinguishable by using different identification methods respectively.

[0041] [5] The plurality of twisted pairs (signal lines 2c) are configured to be distinguishable by the combination of the colors of the insulators (23b) of the pair of insulated wires (23), and the plurality of insulated wires (power lines 2d) have identification patterns provided on their outer surfaces along the longitudinal direction of the cable, and are configured to be distinguishable by the identification patterns, the cable (1a) according to [4].

[0042] [6] The identification pattern is a dot mark, the cable (1) according to [2] or [5].

[0043] [7] A cable (1a) comprising an aggregate (3) in which a plurality of twisted pairs and a plurality of insulated wires are twisted together, and a sheath (5) covering the periphery of the aggregate (3), wherein the twisted pairs and the insulated wires are configured to be distinguishable using different identification methods.

[0044] (Appendix) Although the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. Also, it should be noted that not all combinations of the features described in the embodiments are essential means for solving the problems of the invention. Further, the present invention can be implemented by appropriately modifying it without departing from its gist.

Explanation of Reference Numerals

[0045] 1... Cable 2... Electric wire 22... Insulator 2a... Inner layer electric wire 2b... Outer layer electric wire 2c... Signal line 23... Insulated wire 23b... Insulator 2d... Power line 24... Insulated wire 3... Aggregate 3a... Inner layer 3b... Outer layer 4... Pressing tape 5... Sheath 6... Intervening

Claims

1. An assembly in which a plurality of electric wires configured to be distinguishable by the appearance of their insulators are twisted together in two or more layers, and a sheath covering the periphery of the assembly, wherein among the plurality of electric wires in the assembly, the plurality of electric wires constituting the inner layer, which is the inner layer in the cable radial direction, and the plurality of electric wires constituting the outer layer, which is the layer outside the inner layer in the cable radial direction, are configured to be distinguishable by using different identification methods, a cable.

2. The plurality of electric wires constituting the inner layer are configured to be distinguishable by the difference in the color of their insulators, and the plurality of electric wires constituting the outer layer have an identification pattern printed on their outer surfaces along the cable longitudinal direction, and are configured to be distinguishable by the identification pattern, The cable according to claim 1.

3. The plurality of electric wires constituting the outer layer are configured to be distinguishable by the combination of the identification pattern printed on their outer surfaces, the color of the insulator, and the color of the identification pattern, The cable according to claim 2.

4. An assembly in which a plurality of electric wires configured to be distinguishable by the appearance of their insulators are twisted together in two or more layers, and a sheath covering the periphery of the assembly, wherein the plurality of electric wires include a plurality of pair-twisted wires formed by twisting a pair of insulated electric wires and a plurality of insulated electric wires, and the plurality of pair-twisted wires and the plurality of insulated electric wires are configured to be distinguishable by using different identification methods, a cable.

5. The plurality of pair-twisted wires are configured to be distinguishable by the combination of the colors of the insulators of the pair of insulated electric wires, and the plurality of insulated electric wires have an identification pattern attached to their outer surfaces along the cable longitudinal direction, and are configured to be distinguishable by the identification pattern, The cable according to claim 4.

6. The identification pattern is a dot mark, The cable according to claim 2 or 5.

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