JPH0825030A - Brazed joint structure, brazing device and brazing method - Google Patents

Abstract

PURPOSE:To provide a brazed joint structure, brazing device and brazing method, by which the brazing work can easily be executed and the quality of a product after brazing can be kept good and constant. CONSTITUTION:In faucet type brazed joint structure connecting a lower work 2 of a tubular thick copper conductor and an upper work 1 of a solid copper conductor having smaller vol. than the lower work 2 with a brazing filler metal 6, the tapered surface is formed toward the center on the butting surfaces 3 of the joint part 11 of the upper work 1 and the joint part 12 of the lower work 2. Then, the joint part 12 of the lower work 2 is formed in a projecting shape and the joint part 11 of the upper work 1 is formed in a recessed shape. Further, grooves 4, 5 for containing the swelled-out brazing filler metal after melting are arranged on each of the outer peripheral surface and the inner peripheral surface of the joint part 12. Further, the brazing work is automatically executed with the brazing device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brazing joint structure of a brazing type composed of a solid copper conductor and a tubular copper conductor, and more particularly to a connecting portion of the copper conductor inside a gas insulated switchgear. The present invention relates to a brazed joint structure suitable for use in, a brazing apparatus and brazing method thereof.

[0002]

2. Description of the Related Art The central conductor inside a gas-insulated switchgear, which is one of substation facilities, is constructed by connecting several tubular thick copper conductors of a predetermined length in order to obtain the required length. To be done. At this time, the tubular copper conductors are connected by brazing via a solid copper conductor having a volume sufficiently smaller than that, and the solid copper conductor and the tubular copper conductor are bolted. The reason why the tubular copper conductor is used is that it is adapted to the behavior of a large current of about 10,000 amperes and that the weight is reduced. For brazing a tubular copper conductor and a solid copper conductor, a brazing joint structure of the brazing type is adopted.Normally, the solid copper conductor is placed above and the tubular copper conductor is placed below. , A brazing filler metal is placed on the joint portion and heated. Further, in order to expel gas such as air and gas from the brazing material after the brazing material is completely melted, a method of sliding both copper conductors is adopted.

Since the central conductor inside the above gas insulated switchgear is in a special atmosphere in a completely sealed pressure vessel, it is very troublesome to replace it even if it is defective. Will end up. Therefore, in the brazing joint structure of the copper conductor, it is necessary to maintain the quality of the product after brazing in a good and constant manner and to secure its reliability.

Conventionally, in the brazing joint structure of the copper conductor inside the gas insulated switchgear as described above, as shown in FIG. 10, a solid copper conductor is arranged above and a tubular copper conductor is arranged below. In addition, the solid copper conductor arranged above was formed into a convex shape, and the tubular copper conductor arranged below was formed into a concave shape. Further, the abutting surfaces of the joint portions of both copper conductors were horizontal planes.

Further, although it is not a brazing joint of a brazing type composed of a solid copper conductor and a tubular copper conductor, as a method of brazing by simply processing metal pipes into a brazing type, Japanese Patent Laid-Open No. 62-113312 and Japanese Patent Laid-Open No.
There is one described in Japanese Patent No. 75773. In these conventional techniques, the brazing-shaped connecting portion of the metal pipe to be brazed is formed so that the tapered surfaces face each other.

[0006]

In the conventional brazing joint structure for the copper conductor inside the gas-insulated switchgear, as described above, since the abutting surfaces of the joint portions of both copper conductors are horizontal planes, the brazing material is When completely melted, the brazing filler metal is unlikely to melt into the horizontal flat portion, and voids are likely to form, which easily causes melting defects. Moreover, even if the tubular copper conductor arranged in the lower part and the solid copper conductor arranged in the upper part are made of the same material, the two copper conductors have different shapes, and the tubular copper conductor is the solid copper conductor. Since the tubular copper conductor has a larger volume than the conductor and has a larger surface area, the solid copper conductor is heated faster than the tubular copper conductor during heating for brazing. As a result, the convex solid copper conductor expands rapidly and both copper conductors bite each other, making it impossible to slide both copper conductors to expel gas from the brazing material. From the above, it was difficult to keep the quality of the product after brazing in good condition.

Further, when the brazing material melts, as shown in FIG. 11, the molten brazing material protrudes from between the joint portions, and after the brazing operation, it is necessary to finish the protruding portion with a sander or the like. The number of working steps increases.

Further, in the conventional brazing work, an operator visually confirms that the brazing material has melted while heating the joint part with a gas burner or the like, and after confirming that the brazing material has completely melted, The heating was stopped and both copper conductors were slid to expel gas from the brazing material. The conventional brazing work, which requires the sequential digestion of many such work processes, has to rely on many years of experience of the worker, and the quality of the product after brazing also depends on the worker. It is unavoidable that there are differences, and it was very difficult to keep its quality good and constant.

On the other hand, in the prior art disclosed in the above-mentioned Japanese Patent Laid-Open No. 62-113312 and Japanese Patent Laid-Open No. 4-75773, the connecting portion of the metal pipe to be brazed is formed into a taper shape, so that the brazing material At the time of melting, the brazing material is likely to melt into the connecting portion, and the occurrence of melting defects can be avoided. However, in these conventional techniques, since metal tubes having the same shape are brazed and connected to each other, the above-described difference does not occur in the speed of heating, that is, the speed of expansion, and therefore the galling of the metal tubes is prevented. No problem occurs, and of course, no means has been taken to solve the above-mentioned galling problem. Moreover, the brazing work also depends on many years of experience of the workers, and it is unavoidable that the quality of the product varies depending on the worker, and it is very difficult to keep the quality good and constant.

An object of the present invention is to provide a brazing joint structure capable of easily performing a brazing operation and maintaining good and constant quality of a product after brazing, a brazing method therefor, and a brazing apparatus. Is to provide.

[0011]

In order to achieve the above object, according to the present invention, a tubular copper conductor and a solid copper conductor having a smaller volume than the tubular copper conductor are connected by brazing. In a brazing type brazing joint structure, the solid copper conductor and the tubular copper conductor include an anchoring brazing type joint portion, and the joint portion of the tubular copper conductor has a convex shape, Provided is a brazed joint structure characterized in that a joint portion of a real copper conductor has a concave shape.

In the above brazed joint structure, preferably, at least one of the outer peripheral surface and the inner peripheral surface in contact with the joint portion of the tubular copper conductor is provided with a groove for accommodating the brazing filler metal that has squeezed out after melting.

In order to achieve the above-mentioned object, according to the present invention, in a brazing apparatus for brazing using the brazing joint structure as described above, a solid copper conductor is replaced with a tubular copper conductor. A pressing means for pressing, a heating means for heating the joint portion, a brightness measuring means for measuring the brightness of the brazing material, and a grip for gripping and rotating at least one of the solid copper conductor and the tubular copper conductor. A brazing device is provided which comprises a rotating means.

In order to achieve the above object, according to the present invention, there is provided a brazing method for connecting a tubular copper conductor and a solid copper conductor having a smaller volume than the tubular copper conductor by brazing. , The solid copper conductor and the tubular copper conductor are provided with a joint portion having the brazing joint structure as described above, the tubular copper conductor is arranged below, and the solid copper conductor is arranged above. A brazing material is placed in a portion and heated, and a solid copper conductor is pressed against the tubular copper conductor until the brazing material melts, and the brightness before and after the melting of the brazing material is measured. A brazing method is provided.

In the above brazing method, preferably
After the brazing material is completely melted, at least one of the solid copper conductor and the tubular copper conductor is rotated about its central axis forward and backward by a certain angle to expel gas from the molten brazing material.

In the above brazing method, preferably, the molten state of the brazing material is maintained while at least one of the solid copper conductor and the tubular copper conductor is rotated in the forward and reverse directions. The temperature is kept warm, and after a certain period of time, the forward and reverse rotations and the heating thereof are stopped.

[0017]

In the brazed joint structure of the present invention constructed as described above, the brazing filler metal melted at the time of brazing is provided by providing a taper at the brazing joint portion of the solid copper conductor and the tubular copper conductor. Is easily melted between the joint portions of both copper conductors, and the occurrence of melting defects can be avoided. In addition to this, in the present invention, the joint portion of the tubular copper conductor has a convex shape,
Since the joint part of the solid copper conductor having a smaller volume than the tubular copper conductor has a concave shape, even if the solid copper conductor having a small volume is heated quickly and expands quickly during heating for brazing, both The copper conductors will not bite each other. Therefore, both copper conductors can be slid in the molten brazing material, and the gas can be reliably expelled from the molten brazing material. From the above, it becomes possible to maintain the quality of the product after brazing in good condition.

Further, since at least one of the outer peripheral surface and the inner peripheral surface in contact with the joint portion of the tubular copper conductor is provided with a groove for accommodating the brazing filler metal extruded after melting, the brazing filler metal extruded after the brazing operation is sanded or the like. The work of finishing is unnecessary, and the external appearance is not spoiled by the protruding brazing filler metal.

In the brazing apparatus for brazing using the brazing joint structure as described above, the pressing means for pressing the solid copper conductor against the tubular copper conductor, the heating means for heating the joint portion, and the brazing material. It has a brightness measuring means for measuring the brightness of the material, and a grip rotating means for gripping and rotating at least one of the solid copper conductor and the tubular copper conductor in the forward and reverse directions. Thereby, the brazing method of the present invention described below can be easily carried out, and the brazing operation can be automated.

In the brazing method of the present invention,
A solid copper conductor and a tubular copper conductor are provided with a joint portion having the brazing joint structure as described above, the tubular copper conductor is placed below, and the solid copper conductor is placed above, and the joint portions are Place the brazing material and heat it until the brazing material melts,
Press the solid copper conductor against the tubular copper conductor. Thereby, when the brazing material is melted, both copper conductors can be surely brought into close contact with each other via the brazing material. Further, at this time, by measuring the brightness before and after melting the brazing material, it is possible to confirm that the brazing material is completely melted based on the change in the brightness.

After confirming that the brazing material is completely melted, at least one of the solid copper conductor and the tubular copper conductor is rotated forward and backward by a certain angle around its central axis, whereby both copper The conductor slides and the gas is expelled from the molten brazing material, and the quality of the product after brazing can be kept good and constant.

Further, since the temperature is kept so that the molten state of the brazing material is maintained during the forward and reverse rotations as described above, the gas can be smoothly expelled from the molten brazing material. Then, the brazing work is completed by stopping the forward and reverse rotations and the heating after a certain period of time.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the brazed joint structure, brazing apparatus and brazing method according to the present invention will be described with reference to FIGS. This embodiment relates to a brazing joint structure of a copper conductor which constitutes a central conductor in a gas insulated switchgear.

First, the brazing joint structure of this embodiment is shown in FIG.
This will be described below. The upper work 1 is a solid copper conductor manufactured by forging or machining, and the lower work 2 is a pipe-shaped thick copper conductor. Further, the volume of the upper work 1 is sufficiently shorter and the volume thereof is sufficiently smaller than that of the lower work 2. The features of this brazed joint structure are that the butting surfaces 3 of the joint portion 11 of the upper work 1 and the joint portion 12 of the lower work 2 have a taper, and the joint portion 11 of the upper work 1 is concave and the joint of the lower work 2 is The portion 12 is formed so as to have a convex shape, and the grooves 4, 4 are formed on the outer peripheral surface and the inner peripheral surface of the lower work 2 which are in contact with the joint portion 12.
5 is provided.

By the way, a conventional brazing joint structure of a copper conductor constituting a central conductor inside a gas insulated switchgear has a joint portion 11A of an upper work 1A and a joint 2A of a lower work as shown in FIG. The abutting surface 3A of the portion 12A was a horizontal plane, the joint portion 11A of the solid upper work 1A was formed in a convex shape, and the joint portion 12A of the tubular lower work 2A was formed in a concave shape. Therefore, when the brazing material is completely melted, the horizontal butting surface 3
It was difficult for the brazing filler metal to melt into A, and voids 7A were formed, and melting defects were likely to occur. Even if the upper work 1A and the lower work 2A are made of the same material, they have different shapes, and the lower work 2A has a larger volume than the upper work 1A and the lower work 2A has a larger surface area. , Upper work 1A when heating for brazing
There is a possibility that the above work may be heated and expanded faster than the lower work 2A, and both works may bite each other. Further, when the brazing material is melted, as shown in FIG. 11, the joint portions 11A and 12A
The molten brazing material 6A squeezes out from between the intervals, and it is necessary to finish the squeezed-out portion with a sander or the like after the brazing work, which increases the number of working steps.

On the other hand, in this embodiment, the joint portion 11
Since the abutting surface 3 of the joint portion 12 and the joint portion 12 has a taper, the brazing material melted at the time of brazing is easily melted between the joint portions 11 and 12, and the occurrence of a melting defect can be avoided. Further, since the lower work 2 has a convex shape and the upper work 1 having a smaller volume than the lower work 2 has a concave shape, even if the upper work 1 having a small volume is heated quickly and expands quickly during heating for brazing. The two works do not gnaw with each other, and thus the two works can be slid on each other in a state where the brazing material is melted, as described later. further,
By the groove 4 on the outer peripheral surface and the groove 5 on the inner peripheral surface of the lower work 2,
The brazing filler metal that has extruded after melting is accommodated in these grooves 4 and 5, and there is no need to finish the brazing filler metal that has extruded after the brazing operation with a sander or the like, and the external appearance is not spoiled by the protruding brazing filler metal.

Next, the brazing apparatus of this embodiment will be described with reference to FIGS. FIG. 2 is a view showing the outer appearance of the brazing apparatus of this embodiment, and FIG. 3 is a sectional view showing a work gripping and rotating apparatus which is a part of the brazing apparatus.

In FIG. 2, the brazing apparatus 100 is attached to the brazing apparatus main body 50, a main body lifter 51 for raising and lowering the brazing apparatus main body 50, a support block 52 for supporting the main body lifter 51, and the brazing apparatus main body 50. Work gripping and rotating device 5 for gripping and rotating the upper workpiece
3, a high-frequency current coil 54 for heating attached to the main body 50 of the brazing device, a photometer 55 attached to the work holding / rotating device 53 for measuring the brightness of the molten brazing material, and a positioner 56 for supporting and positioning the lower work 2. A work lifter 57 that raises and lowers the positioner 56, a rail 58 that guides the work lifter 57, and a control panel 59 that automatically controls brazing work. However, in the positioner 56, the work chuck 56a sandwiching the lower work 2 is rotatable in the plane of the disk 56b (see arrow A in the figure), and the disk 56b is the rotating shaft 56.
It can rotate around c (see arrow B in the figure).

In FIG. 3, the work gripping / rotating device 53.
Are chucks 71a, 71b and these chucks 71a,
Chuck mechanisms 70a and 70b having motors 72a and 72b that rotate and drive 71b, respectively.
Ball screw 7 that is screwed into a screw hole that penetrates 0a, 70b
3a and 73b, bevel gears 74a and 74 attached to the respective tip portions of the ball screws 73a and 73b.
b, a bevel gear 75 located on the pipes of the bevel gears 74a and 74b and engaged with each other, and a motor 76 for rotationally driving the ball screw 73a. Further, the limit switch 7 is provided below the frame 77A at the center of the work gripping / rotating device 53.
7 is attached.

Next, the procedure of the brazing work using the brazing apparatus having the above-mentioned structure will be described. First, the positioner 56 is moved to the right side of the paper surface of FIG. 2, that is, to the control board 59 side of the rail 58, and the lower work 2 is attached to the work chuck 56a at that position. This work is a disc 56
It is performed with b being directed right above (see the chain double-dashed line in the figure) and with the work chuck 56a oriented in a direction such that the longitudinal direction of the lower work 2 coincides with the longitudinal direction of the rail 58. Then, the positioner 56 is moved to the left side of the rail 58 on the paper surface, the disk 56b is tilted toward the brazing apparatus main body 50 side around the rotation shaft 56c, and the disk 56b is further rotated in the plane thereof, so that the work chuck 56a, and hence the lower work 2
Stand vertically as shown in FIG. This completes the setting of the lower work 2. The above is step S1 of the flowchart of FIG.

Next, the linear brazing material 6 (see FIG. 5) is set on the lower work 2 in step S2 of FIG. 4, and the upper work 1 is placed on the lower work 2 in step S3. The work of steps S1 to S3 so far is directly performed by the worker.

The subsequent brazing work is performed by the brazing device 10
Automatically set to 0. First, the brazing apparatus main body 50 is lowered by the main body lifter 51, and the high frequency current coil 54 is positioned around the joint portions 11 and 12. Then, the limit switch 77 hits the upper surface of the upper work 1 and is turned ON, and at the same time, the lowering of the brazing main body device 50 is stopped. Next, a high frequency current is passed through the high frequency current coil 54 to heat the joint portions 11 and 12 of the upper work 1 and the lower work 2 (step S4 in FIG. 4). At this time, the upper work 1 is pressed against the lower work 2 while the limit switch 77 is ON until the brazing material 6 is melted.
By pressing the upper work 1 against the lower work 2 in this way, when the brazing filler metal 6 is melted, both the works can be reliably brought into close contact with each other via the brazing filler metal 6. FIG. 5 shows a sectional view around the joint portions 11 and 12 at this time.

Since the brazing filler metal 6 does not flow while the brazing filler metal 6 is not melted, the limit switch 77 remains ON.
The heating in step S4 is continued. When the brazing filler metal 6 melts, the brazing filler metal 6 flows, so that the upper work 1 is lowered and the limit switch 77 is turned off (step S
5).

The brightness before and after melting of the brazing material 6 is measured by the photometer 55, and it is confirmed that the brazing material 6 is completely melted based on the change in the brightness (step S).
6). An example of the relationship between the temperature change of the brazing material and the brightness change thereof is shown in FIG. In FIG. 6, assuming that the brazing filler metal begins to melt at temperature T ₁ and the melting of the brazing filler metal completes at temperature T ₂ , the brightness when the brazing filler metal begins to melt is S ₁ , and the melting of the brazing filler metal is completed. Since the brightness at that time is S ₂ , it can be judged that the time when the brightness measured by the photometer 55 exceeds S ₂ is the time when the brazing material is completely melted. In step S6, it is determined whether or not the luminance measured by the photometer 55 exceeds S ₂ (luminance when the brazing material is completely melted). If not, the heating in step S4 is continued, and if it exceeds, Move to the next step S7. Joint parts 11 and 1 when the brazing material 6 is completely melted
A cross-sectional view near 2 is shown in FIG.

At step S5, the limit switch 77 is turned off.
When it becomes FF and it is confirmed by the photometer 55 that the brazing filler metal 6 is completely melted in step S6, an electric command for performing the next work is input to the high frequency current coil 54 and the work gripping rotation device 53. It In response to the electric command, the high frequency current coil 54 causes the upper work 1 and the lower work 2 to maintain a temperature T at which the molten state of the brazing material 6 is maintained.
_The temperature is kept at ₀ (see FIG. 9) (step S7), and the work gripping rotation device 53 slides the upper work 1 with respect to the lower work 2 as described later (step S8). The reason why the upper work 1 and the lower work 2 are kept at the temperature T ₀ is to prevent the brazing material 6 from solidifying when the upper work 1 is slid in step S8.

Next, the sliding operation of the upper work 1 by the work holding and rotating device 53 will be described. The electric command after the brazing material 6 is completely melted drives the motor 76 to rotate, which causes the ball screw 73a to rotate, and the rotation thereof is transmitted to the ball screw 73b by the bevel gears 74a, 75, 74b, and the ball screw 73b becomes Ball screw 7
It rotates in the opposite direction to 3a. Ball screws 73a and 73
By rotating b in opposite directions, the chuck mechanisms 70a and 70b move toward the center toward each other,
The upper work 1 is sandwiched by the chucks 71a and 71b.
After that, the motors 72a of the chuck mechanisms 70a and 70b,
72b rotationally drives the chucks 71a and 71b in the forward and reverse directions at regular intervals, respectively.
Rotates a certain angle forward and backward, and the upper work 1 moves to the lower work 2
Slide against. As an angle for rotating the upper work 1 forward and backward, an appropriate angle in the range of 30 ° to 60 ° may be selected. By sliding the upper work 1 with respect to the lower work 2 in this way, gases such as air and gas are expelled from the molten brazing filler metal 6, and the quality of the product after brazing is kept good and constant. It becomes possible. Joint parts 11 and 12 when the upper workpiece 1 slides
A cross-sectional view of the vicinity is shown in FIG.

After the sliding operation of the upper work 1 as described above is continued for a certain period of time, in step S9, the high frequency current coil 54 is turned off and the brazing work is completed.

FIG. 9 is a diagram schematically showing an example of the temperature change of the work or the brazing material during the brazing work in this embodiment. As shown in FIG. 9, first, the output of the high frequency current coil 54 is increased to heat the upper work 1 and the lower work 2 to a temperature T (> T ₂ ), and when the brazing material 6 is completely melted (time t ₀ ) Reduce the output of the high frequency current coil 54,
The brazing material 6 is kept at a temperature T ₀ (≦ T) where the molten state of the brazing material 6 is maintained. Then, the upper work 1 is slid with respect to the lower work 2 by the work holding and rotating device 53 while keeping the temperature at T ₀ , the gas is expelled from the molten brazing filler metal 6, and the upper work 1 is slid for a certain period of time. After moving (time t
₁ ) Stop the operation of the work gripping / rotating device 53, and turn off the power of the high frequency current coil 54.

When the above brazing work is completed,
The brazing apparatus main body 50 is once raised, the lower work 2 is inverted, the brazing material and another upper work are placed on the opposite end, and the brazing work is performed in the same procedure.

The features of the brazing apparatus 100 of this embodiment are:
The worker directly carries out the work of attaching the upper work 1 and the lower work 2 and carrying out the work after the brazing work,
All other brazing work is done completely automatically. Of course, in the brazing apparatus 100, it is possible to automate the work of directly attaching the upper work 1 and the lower work 2 by the worker, and carrying out the work after the brazing work is completed. According to this, the brazing work can be completely automated.

According to the present embodiment as described above, since the abutting surfaces 3 of the joint portion 11 of the upper work 1 and the joint portion 12 of the lower work 2 have a taper, the brazing material 6 melted during brazing is the joint portion. It becomes easy to melt between 11 and 12, and it is possible to avoid the occurrence of melting defects. In addition, since the lower work 2 has a convex shape and the upper work 1 having a smaller volume than the lower work 2 has a concave shape, the upper work 1 having a small volume is quickly heated and expands quickly during heating for brazing. Even though both works do not bite each other,
Therefore, the upper work 1 can be slid with respect to the lower work 2 in a state where the brazing material is melted. Furthermore, since grooves 4 and 5 for accommodating the brazing filler metal that has extruded after melting are respectively provided on the outer peripheral surface and the inner peripheral surface of the lower work 2, there is no need to finish the brazing filler metal that has protruded after the brazing operation with a sander, etc. The material does not spoil the appearance.

Further, according to the brazing apparatus 100 of the present embodiment, it is not necessary to rely on the operator's many years of experience, the brazing work can be carried out easily, and automation thereof can be achieved. As a result, it is possible to reduce the number of personnel and improve the efficiency of brazing work.

Therefore, according to the present embodiment, the brazing work can be easily performed, and the quality of the product after brazing can be kept good and constant.

[0044]

According to the present invention, since the joint portions of the solid copper conductor and the tubular copper conductor are tapered, the brazing material is easily melted between the joint portions, and the occurrence of melting defects can be avoided. In addition to this, the joint part of the tubular copper conductor has a convex shape, and the joint part of the solid copper conductor having a smaller volume than the tubular copper conductor has a concave shape. Therefore, it is possible to reliably expel gas from the brazing material by sliding both copper conductors in the molten state of the brazing material.

Since at least one of the outer peripheral surface and the inner peripheral surface of the tubular copper conductor is provided with a groove for accommodating the brazing filler metal that has squeezed out after melting, it is not necessary to finish the surface with a sander or the like, which impairs the appearance. Never.

Further, according to the brazing apparatus of the present invention, the brazing work can be easily carried out without relying on the experience of the operator for many years, the automation can be achieved, and the number of personnel can be reduced. The efficiency of attaching work can be improved.

Therefore, according to the present invention, the brazing work can be easily carried out, and the quality of the product after brazing can be kept good and constant.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a brazed joint structure according to an embodiment of the present invention.

FIG. 2 is a diagram showing an external appearance of a brazing device for brazing the brazed joint structure of FIG.

FIG. 3 is a cross-sectional view showing a work holding and rotating device which is a part of the brazing device of FIG.

FIG. 4 is a flowchart showing a procedure of a brazing operation using the brazing apparatus of FIG.

FIG. 5 is a cross-sectional view of the vicinity of the joint portion when heating the joint portions of the upper work and the lower work.

FIG. 6 is a diagram showing an example of a relationship between a temperature change of a brazing material and a brightness change thereof.

FIG. 7 is a cross-sectional view of the vicinity of the joint portion when the brazing material is completely melted.

FIG. 8 is a cross-sectional view of the vicinity of a joint portion when the upper work is sliding.

FIG. 9 is a diagram schematically showing an example of a temperature change of a work or a brazing material during a brazing operation.

FIG. 10 is a cross-sectional view showing a conventional example of a brazing joint type brazing joint structure of a copper conductor forming a central conductor inside a gas insulated switchgear.

FIG. 11 is a cross-sectional view when the brazing material melts in the brazing joint structure of FIG.

[Explanation of symbols]

 1 Upper Workpiece 2 Lower Workpiece 3 Butt Face 4, 5 Groove 6 Brazing Material 11 Joint Part (Upper Workpiece) 12 Joint Part (Lower Workpiece) 50 Brazing Machine Main Body 51 Main Body Lifter 53 Work Grip Rotating Device 54 High Frequency Current Coil 55 Photometer 56 Positioner 56a Work Chuck 57 Work Lifter 58 Rail 59 Control Board 70a, 70b Chuck Mechanism 71a, 71b Chuck 72a, 72b Motor 73a, 73b Ball Screw 74a, 74b, 75 Bevel Gear 76 Motor 77 Limit Switch 100 Brazing Device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Satoru Shirata 1-1 1-1 Kokubun-cho, Hitachi City, Ibaraki Prefecture Inside the Kokubun Plant, Hitachi, Ltd. (72) Katsuro Ota 1-1-Kokubuncho, Hitachi City, Ibaraki Prefecture No. 1 inside the Kokubun Plant of Hitachi, Ltd. (72) Inventor Osamu Matsushima 1-1 1-1 Kokubuncho, Hitachi City, Ibaraki Prefecture Incorporated at the Kokubun Plant of Hitachi, Ltd. (72) Inventor Shigeru Takeuchi 1-chome, Kokubuncho, Hitachi City, Ibaraki Prefecture No. 1 No. 1 in Hitachi Kokubu Plant, Ltd.

Claims (6)

[Claims] 1. A brazing joint structure of brazing type, in which a tubular copper conductor and a solid copper conductor having a smaller volume than the tubular copper conductor are connected by brazing, wherein the solid copper conductor and the solid copper conductor are The tubular copper conductor comprises a tapered wax-like joint portion, the joint portion of the tubular copper conductor is convex, and the joint portion of the solid copper conductor is concave. Brazing joint structure. 2. The brazing joint structure according to claim 1, wherein at least one of an outer peripheral surface and an inner peripheral surface in contact with the joint portion of the tubular copper conductor is provided with a groove for accommodating the brazing filler metal that has extruded after melting. A brazed joint structure characterized in that 3. A brazing apparatus for brazing using the brazing joint structure according to claim 1 or 2, wherein a pressing means for pressing the solid copper conductor against the tubular copper conductor, and the joint portion are provided. A heating means for heating, a brightness measuring means for measuring the brightness of the brazing material, and a grip rotating means for gripping and rotating at least one of the solid copper conductor and the tubular copper conductor in forward and reverse directions. A characteristic brazing device. 4. A brazing method for connecting a tubular copper conductor and a solid copper conductor having a volume smaller than that of the tubular copper conductor by brazing, wherein the solid copper conductor and the tubular copper conductor are connected to each other. A joint portion having the brazed joint structure according to claim 1 or 2 is provided, the tubular copper conductor is arranged below, the solid copper conductor is arranged above, and a brazing material is arranged on the joint portion to heat the joint. Then, the solid copper conductor is pressed against the tubular copper conductor until the brazing material melts, and the brightness before and after the melting of the brazing material is measured. 5. The brazing method according to claim 4, wherein
After the brazing filler metal is completely melted, at least one of the solid copper conductor and the tubular copper conductor is rotated forward and backward by a certain angle around its central axis to expel gas from the molten brazing filler metal. A brazing method characterized by the following. 6. The brazing method according to claim 5, wherein
While at least one of the solid copper conductor and the tubular copper conductor is rotated in the normal or reverse direction, the temperature is kept so that the molten state of the brazing material is maintained, and the normal or reverse direction is maintained after a certain time. A brazing method characterized by stopping rotation and heating thereof.