KR20210060080A - Cable for robot having an excellent durability - Google Patents

Abstract

The present invention relates to a robot cable having excellent durability. Specifically, the present invention relates to the robot cable having excellent durability and flexibility while at the same time minimizing an external diameter and improving roundness. The robot cable comprises: a center interposition; a communication line and power line; a binder; and a shielding layer.

Description

Cable for robot having an excellent durability

The present invention relates to a cable for a robot having excellent durability. Specifically, the present invention relates to a cable for a robot having excellent durability and flexibility while minimizing an outer diameter and improving roundness.

General industrial robots perform various tasks such as welding, painting, and transfer on a machine part production line. Such an industrial robot is connected to a central control unit or the like by a robot cable, receives necessary power through the robot cable, and further transmits and receives information necessary for various tasks.

However, in this process, the industrial robot continuously moves or moves, and accordingly, fatigue loads such as repetitive tension, twisting, and bending are applied to the robot cable connected to the industrial robot at all times.

1 schematically shows a cross-sectional structure of a conventional robot cable.

As shown in Fig. 1, a conventional robot cable is used in combination with a power line, a control line, and a communication line in order to simplify the use of the cable. Wires such as a communication line 20 for receiving information united in a pair or more, a battery line 30 for transmitting an on/off control signal of an apparatus united in one or more pairs, and a binder 40 covering them as a whole, A shielding layer 50, a sheath layer 60, and the like may be included.

In conventional robot cables, due to the regulation on the finished outer diameter, i.e., minimization of outer diameter and roundness, some wires have to be arranged in the center, and fatigue loads are the most on the wires arranged in the center of the cable during continuous movement or movement of the cable. It is applied, and thus, if a disconnection occurs in the wires arranged in the center of the cable, the entire cable must be replaced, and there is a problem that a considerable time and cost loss for the cable replacement occurs.

Accordingly, there is an urgent need for a robotic cable that has excellent durability and flexibility while minimizing its outer diameter and improving roundness.

An object of the present invention is to provide a cable for a robot having excellent durability and flexibility.

In addition, an object of the present invention is to provide a cable for a robot whose outer diameter is minimized and roundness is improved.

In order to solve the above problems, the present invention,

A central interposition disposed in the center; A communication line and a power line disposed around the center intervening; A binder that entirely surrounds the communication line and the power line; A shielding layer surrounding the binder; And a sheath layer surrounding the shielding layer, wherein the communication line or the power line includes a circular compressed conductor that is compressed as a whole after a plurality of wires are joined, and an insulator surrounding the circular compressed conductor, and It provides a cable for a robot, the adhesion of the insulator to 1.5 to 4.5 kgf / 50mm.

Here, the circular compression conductor constituting the communication line includes a plurality of wire layers, and the plurality of wire layers are formed in a uni-lay method in which the wire layers are twisted in the same direction, providing a cable for a robot. do.

In addition, it further includes a battery line disposed around the central intervening, the communication line is provided in two or more pairs of two or more communication lines united at a constant pitch, the power line and the battery line between the pair It is characterized in that it is arranged, it provides a cable for the robot.

Here, the two or more pairs include a pair having a pitch of 18 to 19.5 mm in which two communication lines are twisted and a pair having a pitch of 15.5 to 17 mm in which two communication lines are twisted, robot Provides a cable for use.

In addition, the power line or the battery line provides a cable for a robot, characterized in that provided in a form in which two power lines or battery lines are combined.

In addition, the battery wire provides a robot cable, characterized in that the two-stranded battery wire is provided in association with a pitch of 13 to 18 mm.

Further, the communication line, the power line and the battery line provide a cable for a robot, characterized in that the combined pitch of 40 to 52 mm as a whole.

On the other hand, the conductor of the power line includes a plurality of wire layers, and the plurality of wire layers provides a robot cable, characterized in that the twisting directions of adjacent wire layers are different.

In addition, it provides a robot cable, characterized in that the thickness of the insulator of the communication line is 0.36 to 0.44 mm.

In addition, the insulator of the communication line includes a high-density polyethylene (HDPE) resin, the insulator of the power line includes an ethylene tetrafluoroethylene (ETFE) resin, and the binder includes a polytetrafluoroethylene (PTFE) resin, , The sheath layer provides a cable for a robot, characterized in that it comprises a polyvinyl chloride (PVC) resin.

The robot cable according to the present invention has excellent durability and flexibility by changing the power line and communication line to which the twisted pair compression conductor is applied, and their arrangement structure, while minimizing the outer diameter and improving the roundness.

In addition, the robotic cable according to the present invention compensates for the communication characteristics of the communication line, which is deteriorated by applying a twisted pair conductor to the communication line for improved flexibility, by adjusting the arrangement structure of the wire, the thickness of the insulation layer, and the pair pitch, thereby reducing communication characteristics of the communication line It exhibits excellent effects that can be minimized or avoided.

1 schematically shows a cross-sectional structure of a conventional robot cable.
Figure 2 schematically shows the cross-sectional structure of the cable for a robot according to the present invention.
3 is an enlarged view of a cross section of a communication line in the robot cable shown in FIG. 2.
FIG. 4 is a diagram illustrating a twisting direction for each layer of a conductor in the communication line shown in FIG. 3.

Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art. The same reference numerals represent the same elements throughout the specification.

Figure 2 schematically shows the cross-sectional structure of the cable for a robot according to the present invention.

As shown in Figure 2, the robot cable according to the present invention is a center interposition 100 arranged in the center of the cable, a communication line 200 for transmitting and receiving information. A power line 300 for supplying power, a battery line 400 for transmitting an on/off control signal, a binder 500 surrounding them, a shielding layer 600, a sheath layer 700, etc. Can include.

The central intervening 100 may be made of a material such as cotton yarn, aramid yarn, polyester yarn, and the like, and bear a significant portion of fatigue loads such as tensile, twisting, and bending applied to the cable, thereby reducing the fatigue load. It is applied to the communication line 200, the power line 300, the battery line 400, etc. to suppress the occurrence of disconnection, and at the same time, the power line 200, the communication line 300, and the battery around the central intervening 100 By arranging the line 400, the overall roundness of the cable is improved, thereby minimizing an increase in the overall outer diameter of the cable.

The communication line 200 has one or more pairs, that is, two pairs of communication lines 200 in a state in which they are united at a constant pitch, preferably two, that is, a first pair 200a and a second pair 200b. It can be equipped with. In this way, when the communication line 200 is provided in two or more pairs, a phenomenon in which noise is generated in a transmission signal of another adjacent pair by an electromagnetic field formed by a current flowing through each pair is adversely affected, that is, crosstalk. ) Phenomenon may occur.

Therefore, in order to suppress or minimize the crosstalk phenomenon in the communication line 200, for example, the power line 200 or the battery line between the first pair 200a and the second pair 200b are spaced apart from each other as much as possible. It is possible to adopt a structure in which 400 is arranged, and the two-stranded communication lines 200 constituting each of the first pair 200a and the second pair 200b are designed differently in a twisted pair pitch. For example, the pitch of the first pair 200a may be 18 to 19.5 mm, and the pitch of the second pair 200b may be 15.5 to 17 mm.

The communication line 200 constituting each of the first pair 200a and the second pair 200b may be formed by coating a communication line insulator 220 on the surface of the communication line conductor 210, and the communication line conductor 210 includes a plurality of It may consist of a circular compression conductor compressed into a circular shape after the two wires are united.

FIG. 3 is an enlarged view of a cross section of a communication line in the robot cable shown in FIG. 2, and FIG. 4 is a diagram illustrating a twist direction for each layer of a conductor in the communication line shown in FIG. 3.

3 and 4, the communication line conductor 210 may have a structure in which a plurality of wires are combined and a plurality of wire layers are sequentially stacked. An empty space between the wires forming the outer wire layer may be minimized.

Accordingly, when the communication line insulator 220 is covered by extrusion or the like on the outermost wire layer, penetration of the insulator into the empty space is minimized or avoided, so that the adhesion between the communication line conductor 210 and the communication line insulator 220 By appropriately adjusting, the communication line conductor 210 and the communication line insulator 220 having different materials when the robotic cable according to the present invention is bent, and thus the expansion rate, elasticity, etc., can behave separately from each other, through which the entire cable Flexibility, bending resistance, etc. can be improved.

For example, the adhesion between the communication line conductor 210 and the communication line insulator 220 may be 1.5 to 4.5 kfg/50mm, and when the adhesive force is less than 1.5 kfg/50mm, the communication line conductor 210 and the communication line insulator While there is a problem that the communication line insulator 200 is contracted because the 220 is easily separated, when the adhesive force is greater than 4.5 kfg/50mm, the communication line conductor 210 and the communication line insulator 220 Since it is difficult to move separately, the flexibility of the cable is deteriorated, and the communication line conductor 210 and the communication line insulator 220 having different materials, expansion rates, and elastic modulus, etc., behave integrally, so that any one of them may be damaged.

The adhesion between the communication line conductor 210 and the communication line insulator 220 is that the exposed conductor of the communication line is partially stripped of the insulator, for example, about 10 mm of the total length of the communication line. After inserting into the hole and setting the insulator to be caught in the hole of the disk, pull the conductor inserted into the hole with a push-pull gauge and measure the force at which the insulator begins to peel from the conductor.

General communication cables require a uniform thickness of an insulating layer to realize communication characteristics, and to implement this, a single conductor with a uniform surface rather than a stranded conductor with an uneven surface has been applied, but the robotic cable according to the present invention is repetitive. Excellent flexibility and bending resistance are required according to the use environment in which phosphorus movement or behavior is inevitable, so that the twisted pair conductor 210 is inevitably applied to the communication line 200.

On the other hand, in the robot cable according to the present invention, the twisted wire conductor 210 is circularly compressed for uniform thickness of the insulator 220 despite the twisted wire conductor 210 being applied, and a plurality of wire layers are in the same direction. While adopting a twisted uni-lay method, communication characteristics can be maintained by making the thickness of the insulator 220 thicker than that of a conventional communication line, for example, 0.36 to 0.44 mm.

The communication line conductor 210 may be made of a conductive metal such as copper, aluminum, or an alloy thereof, and the communication line insulator 220 may be made of a polymer resin such as polyolefin, preferably high-density polyethylene (HDPE).

The power line 300 may be provided in a form in which a pair, that is, two power lines 300 are combined, and each power line 300 is a power line insulator 320 to the power line conductor 310 The power line conductor 310 is a structure in which a plurality of wires are joined together and a plurality of wire layers are stacked, like the communication line conductor 210, and may be formed of a circular compressed conductor that is compressed in a circle as a whole. . However, unlike the communication line conductor 210, the power line conductor 310 may be formed in a manner in which the twisting directions of adjacent wire layers are different.

The power line conductor 310 may be made of a conductive metal such as copper, aluminum, or an alloy thereof, and the power line insulator 320 may be made of a fluororesin, preferably ethylene tetrafluoroethylene (ETFE).

The battery wire 400 may be provided in a form in which a pair, that is, two battery wires 400 are united at a constant pitch, and the large edge pitch of the two battery wires 400 is 13 to 18 mm. In addition, when the edge pitch is less than 13 mm, the flexibility of the battery line 400 may be deteriorated, whereas when it exceeds 18 mm, the bending resistance of the battery line 400 may be deteriorated.

The battery wire 400 may be formed by covering the battery wire conductor 410 with a battery wire insulator 420, and the battery wire conductor 410 may be made of a conductive metal such as copper, aluminum, or an alloy thereof. , The battery wire insulator 220 may be made of a polymer resin such as polyolefin.

The communication line 200, the power line 300, and the battery line 400 may be formed in a structure that is united at a uniform pitch as a whole, and the total united pitch may be 40 to 52 mm. Here, when the joint pitch is less than 40 mm, the flexibility of the cable may be deteriorated, whereas when it is more than 52 mm, the durability such as bending resistance of the cable may be deteriorated.

The binder 500 not only contributes to the structural stability and roundness improvement of the robotic cable according to the present invention by winding the communication line 200, the power line 300, the battery line 400, etc. as a whole, but also the bending resistance of the cable. It contributes to durability improvement, and further performs a function of realizing the communication characteristics of the communication line 200 by separating the shielding layer 600 and the communication line 200 to be described later from each other, for example, polytetra It may include a binder tape made of fluoroethylene (PTFE) or the like.

The shielding layer 600 functions to block the electromagnetic waves from the outside penetrate into the inside of the robot cable according to the present invention or the electromagnetic waves are emitted from the cable to the outside. It may be provided in a braided form.

The sheath layer 700 performs a function of protecting the internal structure of the cable from external impact, pressure, etc., and is made of polyvinyl chloride (PVC) resin having excellent oil resistance, durability, flexibility, and flame retardancy. Can be done.

The robot cable according to the present invention is formed through a structure and design as described above, and in particular, a plurality of wires constituting the conductors of the communication line 200 and/or the power line 300 are joined together, and then the outermost line is compressed. As the empty space between the wires constituting the wire layer is minimized, penetration of the insulator into the empty space is minimized or avoided, so that the adhesion of the insulator to the conductor is precisely controlled, and the conductor and the insulator behave separately when the cable is bent. Flexibility, bending resistance, etc. are improved, and the center intervening 100 is disposed in the center of the cable, the power line 300 and the battery line 400 are disposed between the communication line pairs 200a and 200b, and the communication line and the battery By precisely controlling the pitch of the wire, the overall pitch of the wire, and the thickness of the insulation of the communication line, it is possible to minimize the increase in the outer diameter of the cable, improve the roundness, and maintain the communication characteristics.

[Example]

1. Manufacturing example

The communication line specimen of the embodiment in which the adhesion of the insulator to the conductor is adjusted to 1.5 to 4.5 kgf/50mm by circular compression of a plurality of wires as a whole and the conductor is made of a plurality of wires, but the adhesion of the insulator to the conductor is not compressed as a whole. A communication line specimen of the same comparative example as the communication line was prepared except that it exceeded 4.5 kgf/50mm.

2. Flexibility evaluation

The flexural resistance evaluation was performed on each of the three communication line specimens of Examples and Comparative Examples, and specifically, the other end was repeatedly 180° at a rate of 60 times/min with a load of 250 g applied to one end of the communication line specimen. While bending, the conductor resistance of the communication line specimen was measured. The measurement results are as shown in Table 1 below.

Number of bends Conductor resistance increase rate Example Comparative example 1 million times 1.4% 25% 3.3 million times 1.5% Not measurable (completely disconnected) 6.6 million times 1.9% 10 million times 3%

As shown in Table 1, the communication line of the embodiment applied to the cable for a robot according to the present invention rarely breaks the conductor wire despite repeated bending due to improved durability such as flexibility and bending resistance. In the communication line of the comparative example, it was confirmed that the entire conductor was completely disconnected in about 3 million times of the bending test, and the disconnection of the conductor wire occurred rapidly due to repeated bending.

Although the present specification has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the claims described below. You will be able to do it. Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all should be considered to be included in the technical scope of the present invention.

100: center intervening 200: communication line
300: power line 400: battery line
500: binder 600: shielding layer
700: sheath layer

Claims (10)

A central interposition disposed in the center;
A communication line and a power line disposed around the center intervening;
A binder that entirely surrounds the communication line and the power line;
A shielding layer surrounding the binder; And
Including a sheath layer surrounding the shielding layer,
The communication line or the power line includes a circular compressed conductor that is compressed as a whole after a plurality of wires are combined and an insulator surrounding the circular compressed conductor,
The adhesive force of the insulator to the circular compression conductor is 1.5 to 4.5 kgf / 50mm, the robot cable. The method of claim 1,
The circular compression conductor constituting the communication line includes a plurality of wire layers,
A cable for a robot, characterized in that formed in a uni-lay method in which the plurality of wire layers are twisted in the same direction. The method according to claim 1 or 2,
Further comprising a battery wire disposed around the central interposition,
The communication line is provided with two or more pairs of two or more communication lines united at a constant pitch,
The power line and the battery line, characterized in that disposed between the pair, the robot cable. The method of claim 3,
The two or more pairs include a pair having a pitch of 18 to 19.5 mm in which two communication lines are twisted and a pair having a pitch of 15.5 to 17 mm in which two communication lines are twisted, a robot cable . The method of claim 3,
The power line or the battery line is a robot cable, characterized in that provided in the form of a combination of two power lines or battery lines. The method of claim 5,
The battery wire is characterized in that the two-stranded battery wire is provided with a pitch of 13 to 18 mm, robot cable. The method of claim 3,
The communication line, the power line, and the battery line, as a whole, characterized in that the combined pitch of 40 to 52 mm, robot cable. The method according to claim 1 or 2,
The conductor of the power line includes a plurality of wire layers,
The plurality of wire layers is a robot cable, characterized in that the twisting direction of the adjacent wire layers are different. The method according to claim 1 or 2,
The insulator thickness of the communication line is 0.36 to 0.44 mm, characterized in that the robot cable. The method according to claim 1 or 2,
The insulator of the communication line includes a high-density polyethylene (HDPE) resin,
The insulator of the power line includes ethylene tetrafluoroethylene (ETFE) resin,
The binder includes a polytetrafluoroethylene (PTFE) resin,
The sheath layer is characterized in that it comprises a polyvinyl chloride (PVC) resin, a robot cable.

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