JPH05290640A - Welding cable - Google Patents

Abstract

PURPOSE:To extend the life or a welding cable, enhance the operation rate of facility and facilitate manufacture of the welding cable by effectively restraining the connecting end portion of the feed conductor of the welding cable from curving, so as to prevent disconnection of the wire at early stages. CONSTITUTION:A protecting net 9 is directly put over the connecting end portion 8a of a feed conductor 8 so as to cover the connecting end portion 8a with the protecting net 9 and a ring-shaped member 10 made of a conductive material is fitted around the outer periphery of the protecting net 9 and is then tightened so that the protecting net 9 and the ring-shaped member 10 are integrally attached to the connecting end portion 8a of the feed conductor 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding cable which is used by being attached to a welding robot, a multi-welding machine or the like.

[0002]

2. Description of the Related Art As a welding cable of this type, there are, for example, a water cooling cable for a portable spot welding machine and an air cooling cable for a multi welding machine. These cables are
Since it is used under extremely severe usage conditions, it does not last long and there is a problem that it will be disconnected early.

That is, in the spot welding machine 20 as shown in FIG. 8, as the welding gun 21 is operated, the connection end 22a of the welding cable 22, particularly the connection end 22a with the transformer 23, is locally applied. A sharp bend occurs. Since the welding gun 21 repeats the severe movement while bending the welding cable 22, the welding cable 22
There was a possibility that the connection end portion 22a of (1) would be disconnected (early disconnection) in a short period of time.

Further, as shown in FIG. 9, the spot welding is performed by arranging the transformer 24 at a position distant from the welding gun 25 and supplying power to the welding gun 25 through the kickless cable 26 and the auxiliary cables 27a and 27b sequentially. In the machine 28 as well, as in the case of the spot welder 20 described above, the connection ends 29a, 29b of the auxiliary cables 27a, 27b may be broken in a short period of time. That is, in the spot welder 28, since the kickless cable 26 is a unit state in which reciprocating cables having different current directions are insulated and set in a case such as a hose, the kickless cable 26 has a unit state. The electric repulsive force generated between the reciprocating cables stops in the hose, and kick does not occur as one kickless cable. However, in the case of the non-kickless auxiliary cables 27a and 27b, when energized, large currents flowing in different directions flow and a strong magnetic field is generated around them, and this magnetic field repels the two auxiliary cables 27a and 27b. Acts like
In addition, since alternating current also causes vibration, this causes local bending,
As a result, it causes an early disconnection.

Therefore, in order to prevent the disconnection of the cable 22 or the auxiliary cables 27a and 27b as described above, a protective net is put on the outer circumference of the rubber hose corresponding to the connecting end of the cable, thereby bending the connecting end. A proposal (Japanese Unexamined Patent Publication No. 1-249275) has been made to soften and reduce disconnection.

[0006]

However, in the welding cable proposed hitherto, a protective net is indirectly covered from the outside of the rubber hose (jumper hose) to the feeding conductor inside the rubber hose. Therefore, the fact that the restraint force of the power supply conductor by the protective net is quite small, and the effect of preventing the disconnection due to the sufficient restraint force cannot be obtained. Especially when the rubber hose is just an insulating cover, as in the case of air-cooled cables,
The restraining force acting on the power feeding conductor itself is further reduced.

Therefore, in the past, a protective net was put over the outer circumference of the rubber hose (insulation case) at the connection end of the welding cable to soften the bending of that part, but the effect is not sufficient. We could not expect much longer service life of welding cables.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a structure that can effectively prevent early disconnection and can significantly extend the life. To provide a welding cable.

[0009]

In order to achieve the above-mentioned object, in the present invention, the connecting end portion of the power supply conductor is directly covered with a protective net to cover the connecting end portion with the protective net,
By crimping the ring-shaped member with the ring-shaped member made of a conductive material fitted on the outer periphery of the protective net, the protective net and the ring-shaped member can be integrally attached to the connection end of the power supply conductor. I have to.

Further, in the present invention, a portion of the protective net to which the ring-shaped member is fitted and a portion in the vicinity thereof are multi-knitted.

[0011]

[Function] Since the protective net is directly covered not on the outer circumference of the rubber hose (insulation case) at the connection end of the power supply conductor but on the outer circumference of the connection end of the power supply conductor, the bending of this connection end is effectively softened. As a result, early disconnection of the welding cable is prevented. Further, the protective net can be easily attached to the connection end of the power supply conductor by crimping the ring-shaped member made of a conductive material in a fitted state.

When the protective net is multi-knitted as described above, the toughness of the protective net is greatly improved at the portion where the bending needs to be particularly softened, that is, the tubular member fitting portion of the feed conductor. Therefore, disconnection can be prevented more effectively in this portion.

[0013]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows a welding cable 1a according to the present invention,
1 shows a spot welder (welding robot) 2 equipped with 1b, and these welding cables 1a and 1b are used as part of a secondary cable of the spot welder 2. As shown in FIG. 1, the spot welding machine 2 is provided with a welding gun 4 at the tip of an arm 3, and the arm 3 and the welding gun 4 are automatically operated by a controller (not shown).

Further, the transformer 5 is fixedly arranged separately from the arm 3, and power is supplied from the transformer 5 to the welding gun 4 via the secondary cable 6. The above-mentioned secondary cable 6 is composed of the above-mentioned two welding cables (auxiliary cables) 1a and 1b and one kickless cable 7, and these welding cables 1a and 1b
1b is connected in parallel between the kickless cable 7 and the welding gun 4.

The kickless cable 7 is a unit made by insulating cables having different current directions and setting them in a rubber hose or the like.
Each of a and 1b is a cable in which a current flows only in one direction. Therefore, when the secondary cable 6 is energized, the electric force does not appear as the kick of the cable in the kickless cable 7, but the current directions of the two welding cables 1a and 1b are opposite to each other. A large repulsive force is generated between them. Together with this, the welding cables 1a and 1b are severely swung together with the arm 3 during the spot welding operation.
Of a and 1b, especially both ends thereof, that is, connection end parts A and B
A sharp bend tends to occur.

Therefore, in order to cope with such a sharp bend, in the present example, the connecting end portion 8a of the power supply conductor 8 (see FIGS. 2 and 3) corresponding to the connecting end portions A and B has a cylindrical shape. The protective net 9 is directly covered, and the protective net 9 is used to connect the connecting end 8a.
Are coated (see FIGS. 4 and 5). This protection net 9
4A or 5A, the stainless wire 9a is obliquely woven to form a tubular shape, and the stainless wire 9a is the welding cable 1
Directly arranged in a mesh shape over the entire outer periphery of the connection end portion 8a of the power feeding conductors 8a and 1b. Then, ring-shaped members (copper rings) 10 made of a conductive material (for example, copper) are fixed to the connection end portions 8a covered with the protective net 9.

Here, the manufacturing process of the welding cables 1a and 1b will be specifically described.

First, when the water-cooled welding cables 1a and 1b shown in FIG. 2 are manufactured, as shown in FIG. (Part) 8a is covered with a protective net 9 made of stainless wire, and a ring-shaped member (copper ring) 10 made of copper is fitted to the end portion of the protective net 9 as shown in FIG. 4B. Next, as shown in FIG. 4 (C), the ring-shaped member 10 and the protective net 9 are pressed together with the connecting end portion 8a of the power feeding conductor 8 to be crimped into a predetermined shape, so that the ring-shaped member 10 formed into the predetermined shape is pressed. The connection terminal 11 having the cable mounting hole 11a and the nipple mounting hole 11b is fitted on the outer periphery,
The connection terminal 11 is joined to the ring-shaped member 10 by soldering. Then, as shown in FIG. 4 (D), the jumper hose 12 is put on the outer circumferences of the protective net 9 and the power feeding conductor 8,
As shown in FIG. 4 (E), both ends of the jumper hose 12 are tightened with the hose bands 13. And finally,
The hose nipple 14 is attached to the connection terminal 11, and the manufacture of the water-cooled welding cables 1a and 1b is completed.

When manufacturing the air-cooled welding cables 1a and 1b shown in FIG. 3, the protective net 9 and the copper ring-shaped member are provided at the connection end 8a of the power supply conductor 8 as in the case described above. 10 (see FIG. 5A), the ring-shaped member 10
Is crimped together with the protective net 9 and the power feeding conductor 8 by a press to form, for example, a quadrangular prism shape (see FIG. 5B). Next, as shown in FIG. 5C, a cable mounting hole 16 is formed in the crimped portion (connection terminal portion) 15. In this case, since the power supply conductor 8 reaches the end of the ring-shaped member 10 and the cable mounting hole 16,
There is no problem of poor electrical contact without soldering unlike the water cooling type. When the welding cables 1a and 1b are arranged in a place where insulation from the outside is required, the welding cable
As shown in (D), an insulating hose 17 is put on the outer circumferences of the feeding conductor 8 and the protective net 9 except for the crimped portion 15. This completes the manufacture of the air-cooled welding cables 1a and 1b.

Thus, the water-cooled or air-cooled welding cables 1a, 1b use the cable mounting holes 11a or 16 so that both ends of the welding cables 1a, 1b are kickless cables 7.
And the welding gun 4 are electrically connected.

The welding cables 1a, 1 having the above-mentioned structure
According to b, since the connecting net 8a of the power feeding conductor 8 housed in the hose 12 or 17 is directly covered with the protective net 9, this protective net 9 is attached to the outer circumference of the hose 12 or 17. Compared with the case, the effect of softening the bending of the connection end portion 8a of the power feeding conductor 8 can be obtained more significantly.
The reason is that since there is no inclusion such as a hose between the power feeding conductor 8 and the protective net 9, the connecting end portion 8 of the power feeding conductor 8 is not present.
This is because the stress (flexing force) is directly received by the protective net 8 when the wire is about to be bent, and the stress is dispersed over the entire power supply conductor 8.
In particular, when bending occurs such that a force in the direction opposite to the twisting direction of the wires forming the power supply conductor 8 acts, the power supply conductor 8 is untwisted and the wires are distorted, or the wires are twisted. Although there is a possibility that a buckling phenomenon may occur in the wire and the wire may be disconnected, if a structure is adopted in which the protective net 9 is directly covered with the power supply conductor 8,
Since the protective net 9 has a structure for tightening the whole of the power feeding conductor 8, it is possible to effectively prevent the occurrence of the wire breaking phenomenon and the wire breakage. Furthermore, it is possible to prevent the connection ends of the welding cables 1a and 1b from being broken.

Further, according to this embodiment, the space for mounting the spot welding machine 2 is not restricted as compared with the case where the protective net is mounted from the outside of the cable, and it is advantageous in terms of cost.

Furthermore, the welding cables 1a and 1b of this example
In manufacturing the cable, the ring-shaped member 10 is pressed onto the power feeding conductor 8 during the cable manufacturing process, and at the same time, the protective net 9 is pressed.
Since they are pressed together and caulked, the protective net 9 can be easily and efficiently attached.

6 and 7 show a second embodiment of the present invention. In this embodiment, a ring-shaped member of the protective net 9 which covers the connecting end 8a of the power supply conductor 8 is used. The end portion α to which 10 is fitted and this ring-shaped member 10
The portion β in the vicinity of is composed of multiple knitting. That is,
In addition to the twill weave with one stainless wire 9a, one stainless wire 9a is further overlapped and knitted in the portions α and β to form a double knit. The portion γ other than these portions α and β (the portion distant from the end of the feeding conductor 8) is a single knit as in the above-described embodiment.

With this structure, since the toughness of the portions α and β of the protective net 9 corresponding to the connection end 8a of the power feeding conductor 8 which receives the strongest bending force is significantly improved, the welding cable 1a is provided. , 1b, the bending occurring at the connection end A (B) can be softened more effectively, and therefore, the life until the feed conductor 8 is broken can be further extended significantly, which in turn causes a cable break. It is possible to reduce equipment down time and improve equipment operation rate.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and changes can be made based on the technical idea of the present invention. is there. For example, although the present invention is applied to the welding cables 1a and 1b that are not kickless in the above-described embodiment,
The present invention can also be applied to the kickless cable 7. In this case, the power supply conductors having different current directions, which are units, may be divided and covered with a protective net in an insulated state. Further, the portions 8a and 8b of the protective net 8 can be changed to triple, quadruple, etc. instead of double knitting, and the toughness of the portions α and β can be secured as necessary depending on the degree of the multiple knitting. It is possible.

[0028]

As described above, according to the present invention, the connecting end portion of the feeding conductor is directly covered with the protective net.
Since the bending that occurs at the connection end of the power supply conductor is directly received by the protective net and is softened, early disconnection of the welding cable can be effectively prevented and the life of the welding cable can be greatly extended. It is possible to extend it. In addition, it is possible to reduce the equipment downtime due to the cable breakage and improve the equipment operating rate.

Further, a conductive ring-shaped member is fitted to the outer periphery of the protective net covering the connecting end of the power feeding conductor and the three members are caulked together to feed the protective net and the ring-shaped member. Since it is integrally attached to the conductor, the welding cable can be easily manufactured, and the manufacturing cost can be reduced.

Further, the fitting portion of the ring member and its vicinity portion of the protective net, that is, the portion of the connection end portion of the feed conductor on which a particularly large bending force acts is made into the multiple knitting, so that the multiple knitting portion. As a result, the toughness is improved, and the bending that occurs at the connection end of the welding cable can be alleviated more effectively.

[Brief description of drawings]

FIG. 1 is a perspective view of a spot welding machine including a welding cable according to the present invention.

FIG. 2 is a perspective view of a water-cooled welding cable.

FIG. 3 is a perspective view of an air-cooled welding cable.

4 (A), (B), (C), (D) and (E) are perspective views showing a manufacturing process of a water-cooled welding cable.

5 (A), (B), (C) and (D) are perspective views showing a manufacturing process of an air-cooled welding cable.

FIG. 6 is a side view of a welding cable showing a second embodiment of the present invention.

7 is a sectional view taken along line VII-VII in FIG.

FIG. 8 is a side view of a spot welding machine including a conventional welding cable.

FIG. 9 is a side view of another spot welding machine including a conventional welding cable.

[Explanation of symbols]

 1a, 1b Welding cable (auxiliary cable) 2 Spot welding machine (welding robot) 8 Power supply conductor 8a Connection end 9 Protective net 10 Ring-shaped member (copper ring) 11 Connection terminal 12 Jumper hose 17 Insulation hose α End part β Neighborhood

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Haruichi Suzuki 300, Takatsuka-cho, Hamamatsu City, Shizuoka Prefecture Suzuki Stock Company (72) Inventor Kazutaka Fukushima 1-15-13 Nishiki, Naka-ku, Nagoya City, Aichi Prefecture Japan Flex Stock Company (72) Inventor Kenichi Fukuya 1-15-13 Nishiki, Naka-ku, Nagoya-shi, Aichi Japan Flex Co., Ltd.

Claims (2)

[Claims] 1. A state in which a connecting net of a power supply conductor is directly covered with a protective net to cover the connecting end with the protective net, and a ring-shaped member made of a conductive material is fitted to the outer periphery of the protective net. The welding cable, wherein the protective net and the ring-shaped member are integrally attached to the connection end of the power supply conductor by swaging the ring-shaped member. 2. The welding cable according to claim 1, wherein a portion of the protective net to which the ring-shaped member is fitted and a portion in the vicinity thereof are multi-knitted.