JPH0254192B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Related Technical Field) The present invention relates to a water-cooled cable for spot welding used in the automobile industry, train manufacturing industry, shipbuilding industry, and other electrical product manufacturing lines.

When performing spot welding, the welding gun is operated at various angles depending on the location to be welded, so that repeated physical fatigue such as bending and twisting is applied to the cable. Furthermore, the welding current is 8000 amperes ~
The high current of 15,000 amperes causes the cable to heat up and repeat. Also, when this current is applied, a shock called a shock is generated, so that the cable core wires hit each other strongly. Such physical fatigue and electrical shock are concentrated on the operating section near the fixed terminal section, and act repeatedly on the cable each time a spot is struck, resulting in breakage of the operating section. At the same time, each time a large current flows, the cable temperature rises, causing overheating and disconnection, making the cable unusable.

Of course, if it becomes unusable, you will have to replace it, but of course the cost of the cable will be high.
The loss of operating time required for replacement and the cost associated with the man-hours required to replace the cable are significant. It is extremely uneconomical that it takes a considerable amount of time just to replace a cable, even though the production line is running at a production rate of one unit every tens of seconds.

(Prior Art) FIG. 4 shows the end structure of a known water-cooled cable.
In FIG. 4, reference numeral 1 denotes a machined terminal metal fitting made of, for example, brass, and the main body portion 1a is cylindrical and has a concentric water passage hole 2 through which cooling water passes. Reference numeral 1b denotes a mounting portion, which has a rectangular cross section and is provided with a mounting hole 3. Reference numeral 1c denotes a notch in the main body, into which cable core wires 5 made of a plurality of bare copper wires are crimped and connected by a mounting ring 4. The crimp joint is crimped so as to form a recess 6 in the portion, as shown in FIG. This recess 6 allows the cooling water to flow as indicated by the arrow a in Fig. 4.
It passes like this. Reference numeral 7 denotes a groove provided on the outer periphery of the main body portion 1a, into which a hose 8 is tightened by a tightening tool 9. 10 is a nipple, and the main body part 1a
It is screwed into a screw hole 11 provided in the. A water supply pipe 12 is attached to the nipple 10. Although only one end is shown in the figure, the other end has a similar configuration, and cooling water is passed from one end to the other to cool the cable core wire 5, which becomes hot.

Now, in this configuration, the terminal hardware 1 is made by machining a "solid" round bar, and the machining is not easy. In addition, although the terminal hardware 1 is reused after removing the cable core wire 5, high pressure is applied to the cable crimp joint each time, and although it is not visible to the naked eye, cracks occur, and the cable is reused about 3 times. If you replace it, it will no longer be usable.

(Object of the Invention) The present invention improves the terminal hardware in the prior art as described above, and even if repeated bending stress is applied to the joint between the cable core wire and the terminal hardware, the degree of fatigue at that part is low, and therefore, the fatigue level of that part is low. The object of the present invention is to provide a water-cooled cable that is difficult to cut.

In addition, by simplifying the structure than before,
Another object of the present invention is to provide a water-cooled cable that is easy to manufacture and therefore inexpensive to provide.

Furthermore, with such an inexpensive and durable water-cooled cable, we are trying to provide a water-cooled cable that is fully cost-effective without the need to use the water-cooled cable as a consumable item and reuse the terminal hardware as in the past. It is something to do.

(Summary of the configuration) Terminal metal fittings are fixed to both ends of a cable core wire made of multiple non-insulated wires, and a hose is attached between the terminal metal fittings at both ends to cover the cable core wire and to pass cooling water for cooling the cable core wire. In a water-cooled cable for welding, the terminal hardware is made of a copper pipe with a circular cross section, and has a mounting part with a rectangular cross section that is crimped and fixed to the end of the cable core with a press, and is smoothly connected to the mounting part, and the cable core is connected smoothly to the mounting part. and a main body portion with a large diameter and a circular cross section that provides a water passage space between the mounting portion and the main body portion with a large diameter circular cross section, and the connecting portion between the mounting portion and the main body portion with a large diameter and circular cross section is approximately oriented toward the main body portion with the circular cross section. The mounting portion has a conical lattice-shaped expansion portion, and the mounting portion and the lattice-shaped expansion portion, each having a square cross section, are connected by a concave curve facing the main body.

(Example) An example will be described with reference to FIGS. 1 to 3. 13 is a terminal hardware according to the present invention, which is made of a relatively thick copper pipe as a raw material. 14
is a cable core wire made up of countless bare copper wires fixed to the terminal hardware 13. To fix the cable core wire 14 and the terminal metal fitting 13, their ends are aligned and one end of the terminal metal fitting is pressed so that the cross section becomes a rectangular shape.

The crimp joint has a rectangular cross section, and this portion serves as the attachment portion. A hole 16 into which the pipe 15 is inserted is bored in the mounting portion 13a. A pipe 15 is fitted into this hole 16, and both ends 17 of the pipe 15 are brazed to the mounting portion 13a and sealed. The end 18 of the cable core wire 14 is also brazed and the end is completely sealed. In this case, the cable core wire 14 is immersed in a melted soft metal such as solder, and the soft metal is infiltrated between each core wire, which is then inserted into a copper pipe and press-molded.
Alternatively, a method may be used in which the core wire 14 is inserted into a copper pipe and molded, and then a soft metal such as solder is applied in a plating manner to the molded surface having a rectangular cross section for surface treatment.

Reference numeral 19 denotes a concave groove provided for attaching a hose 20, which is secured by tightening with a fastener 21, as in the known example. A nipple 22 is screwed into a screw hole 23 provided in the terminal metal fitting 13 to be attached. 24 is a water supply hose. Reference numeral 25 denotes a chamfered portion of the terminal metal fitting, which is provided to protect the cable core wire 14.

Reference numeral 26 denotes a connecting portion between the large-diameter main portion 13b of the terminal hardware 13 and the mounting portion 13a having a rectangular cross section, and is configured with a conical expanding portion that expands smoothly, thereby repeatedly bending the cable core. Even if you do, it will not break. In this case, if the copper pipe is simply pressed to form the mounting part 13a with a rectangular cross section, the connection part between the main body part 13b and the mounting part 13a will be connected with a straight bent part, and the cable core wire inside this part will be connected. adversely affect the lifespan of.

In order to prevent this, the present applicant previously invented an air-cooled cable disclosed in Japanese Patent Publication No. 59-22628 or U.S. Pat. In order to leave as much as possible after molding, the expanded part and the mounting part 1 with a rectangular cross section
Press molding is performed so that a concave curve 27 toward the widened portion 26 is formed at the connection portion with 3a as shown in FIG.

In FIG. 6, unlike the previous embodiment, the mounting portion 13a and the main body portion 13b are tilted at an angle of approximately 30°. Even in this configuration, the circular cross-section of the main body and the rectangular cross-section of the mounting portion are connected by an expanding portion that expands smoothly, and the structure is such that the core wire is prevented from breaking due to bending, as in the above embodiment. is exactly the same.

(Effect) Mounting part 13a with a square cross section and main body part 1 with a circular cross section
Since the connection part 26 with 3b is a substantially conical expanded part, even if this part is bent or twisted during welding work, the cable core can be bent or twisted easily, so the cable can be easily bent or twisted. No damage and long service life can be guaranteed.

Further, the expanded portion and the mounting portion having a rectangular cross section are smoothly continuous. That is, since the connection is made with a concave curve 27 facing toward the enlarged portion side, even if the cable core wire is bent at this portion during welding, it will not be bent at an acute angle, so no stress is applied, and its durability is outstanding.

The material is relatively thick copper pipe, and the cable core wire is crimped and bonded with a press, making the construction of the water-cooled cable simple.
Can be provided at low cost. Therefore, the water cooling cable itself can be used as a consumable item, and the time required for replacement can be greatly reduced.

If you braze the ends of the cable core or the mounting holes, there will be no water leakage, and the function as a water-cooled cable is no different from conventional products.
The advantages of spot welding machines are enormous.

[Brief explanation of drawings]

FIG. 1 is an end sectional view of the water-cooled cable of the present invention.
FIG. 2 is a sectional view taken along the arrow in FIG. FIG. 3 is a perspective view of the attachment part and the expansion part. FIG. 4 is a sectional view of a conventional water-cooled cable. FIG. 5 is a sectional view taken along the arrow in FIG. 4. FIG. 6 is a sectional view showing another embodiment. In the figure: 1...(machined) terminal hardware, 2...water hole, 3...mounting hole, 4...mounting ring, 5...cable core wire, 6...dent, 7...
Concave groove, 8... Hose, 9... Fastener, 10... Nipple, 11... Screw hole, 12... Water supply pipe, 13
...Terminal hardware, 13a...Mounting part, 13b...Body part, 14...Cable core wire, 15...Pipe,
16... Hole, 17... End of pipe, 18... End of cable core wire, 19... Concave groove, 20... Hose,
21... Fastener, 22... Nipple, 23... Screw hole, 24... Water supply hose, 25... Chamfered part (of terminal hardware), 26... Connection part (between mounting part and main body part) , 27...concave curve.

Claims (1)

[Claims] 1 Welding in which terminal metal fittings 13 are fixed to both ends of a cable core wire 14 consisting of a plurality of non-insulated wires, and a hose 20 is attached between the terminal metal fittings at both ends to cover the cable core wire and to pass cooling water for cooling the cable core wire. In the water-cooled cable, the terminal hardware 13 is made of a copper pipe with a circular cross section, and is smoothly connected to a mounting portion 13a with a square cross section that is crimped and fixed to the end of the cable core wire 14 with a press. , a main body part 13b having a large diameter and a circular cross section that provides a water passage space between the cable core wire 14, and a connecting part between the mounting part 13a and the large diameter main part 13b having a circular cross section. It is characterized by forming a generally conical lattice-shaped widened portion toward the main body portion 13b side, and the attachment portion 13a having a rectangular cross section and the lattice-shaped widened portion are connected by a concave curve facing toward the main body portion 13b. Water-cooled cable for spot welding.