JPH0966358A - Automatic brazing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically braze a body to be connected having connected both ends in closed state by forming a U-shaped coil having an opening capable of insertedly passing through the connected body along the direction crossing at right angles to the butting direction of the body to be connected. SOLUTION: The automatic brazing device is constituted of a brazing unit 1 for brazing the body to be connected and a manipulator 2 for shiftably supporting the unit 1. The coil 6 in the unit 1 is constituted of heating conductors 11 and a bridging conductor 12 for connecting the base ends of the heating conductors. The coil 6 is formed in a U-shape while having an opening hole 6a at the tip end. The coil 6 is shifted with the manipulator 2 and superposed on the body to be connected from the opening hole 6a. A position detecting part 8 guides the body to be connected to a prescribed position by the coil 6. A brazing filler metal is supplied from the tip part 3a of a brazing filler metal supplying part 3 and heated with the coil 6 while detecting the temp. of the joining position with a temp. detecting part 7 to execute brazing. Even in the case of the structure of the body to be connected impossible to execute automatic brazing with the conventional method, the automatic brazing can be applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic brazing apparatus for brazing a joint portion of a body to be connected by using high frequency induction heating.

[0002]

2. Description of the Related Art Conventionally, when a large amount of objects to be connected such as pipes are brazed and connected, an automatic brazing device using a gas burner is used as shown in Japanese Patent Publication No. 3-73384. Has been. However, due to its structure, this gas burner type automatic brazing device cannot completely eliminate the effect of the flame of the gas burner on the peripheral portion of the joint portion, and the size and high density of the peripheral portion of the joint portion can be reduced. As a result, the number of cases where brazing was impossible was increasing.

Therefore, recently, an automatic brazing apparatus using high frequency induction heating is used as a brazing apparatus adaptable to miniaturization and high density of the peripheral portion of the joint portion. As shown in FIG. 16, this induction heating type automatic brazing apparatus encloses the joint portions Ha of the pipes (connected bodies) H, which are butted to each other, and encircles the joint portion Ha to perform high frequency induction heating.
After mounting the ring type brazing 71 on the joint portion Ha, a high frequency is applied to the annular coil 70 surrounding the joint portion Ha, and the joint portion Ha
Induction heating is caused to melt the ring-shaped wax 71,
With this, the joint portion Ha is brazed.

As is well known for induction heating, when a high frequency current is passed through a coil which surrounds an object to be heated, an eddy current is induced in the object to be heated by a magnetic field generated according to the magnitude of the current. Therefore, the portion through which the current flows generates heat due to the electric resistance of the object to be heated.

[0005]

However, although the conventional induction heating type automatic brazing apparatus is suitable for reducing the size and increasing the density of the peripheral portion of the joint portion Ha, the connected body H
There was a problem that it could not be used depending on the shape of. That is, in the connected body H in which the upper and lower parts of the joint portion Ha are connected to other members to form a non-open shape, such as a pipe constituting an outdoor unit of an air conditioner, the annular coil 70
It was not possible to attach it to the machine and automatic brazing could not be performed.

Further, since the high frequency induction heating is a local heating method, in the induction heating type automatic brazing apparatus, in order to perform stable brazing on the connected object H having a variation in the mounting position, the It is necessary to accurately position the annular coil 70 with respect to the connection body H, accurately measure the heating temperature of the connected body H, and feed back the measurement result to control the heating power. The automatic brazing device does not include a mechanism for accurately measuring the heating temperature of the connected body H, and further does not include a mechanism for accurately positioning the annular coil 70 with respect to the connected body H.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an automatic brazing apparatus capable of accurately brazing any position.

[0008]

In order to achieve the above-mentioned object, the first aspect of the present invention comprises a coil for inductively heating the joint portion of at least a pair of objects to be connected in abutting relation. Is characterized by being formed in a U shape having an opening through which the connected body can be inserted along a direction orthogonal to the butting direction of the connected body.

According to a second aspect of the present invention, there is provided a coil for surrounding and inductively heating the joint portion of at least a pair of objects to be connected, the brazing material supplying portion for supplying the brazing material to the joint portion, and the joint portion. And a temperature detecting section for measuring the temperature of the coil, and the coil has a leading end of the brazing filler metal supply section and / or an introducing section for guiding the temperature detecting section from the outside of the coil to the joint portion. It has features.

According to a fifth aspect of the present invention, a coil that surrounds the joint portions of at least a pair of connected bodies that are arranged in abutting manner and that performs induction heating, and a repulsive force that acts between the connected body and each position of the coil are used for driving. And a position correction mechanism for moving the coil to a position where the repulsive force is balanced.

According to a ninth aspect of the present invention, there is provided a coil which surrounds a joint portion of a body to be connected and is induction-heated, and a measuring mechanism which measures a repulsive force or a suction force acting between the body to be connected and each position of the coil. And a moving mechanism for moving the coil to a position where the repulsive force or the suction force measured by the measuring mechanism are balanced with each other.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of an automatic brazing apparatus according to an embodiment of the present invention.

This induction heating type automatic brazing apparatus is a brazing unit 1 for performing a brazing operation on a body H to be connected.
And a 6-axis manipulator 2 that supports the brazing unit 1 so as to be movable in all directions, a brazing material supply unit 3 that supplies a linear brazing material L to the brazing unit 1, and operations of the 6-axis manipulator 2 are controlled. The manipulator controller 4 and the main controller 5 that controls the entire apparatus are provided.

As shown in FIG. 2, the brazing unit 1 includes a coil 6 for high frequency induction heating provided at the tip of an arm 2a of a 6-axis manipulator 2 and a joint portion Ha (see FIG. 6).
Etc.) and a joint portion H
The position detection unit 8 detects the three-dimensional position of a. The temperature detector 7 is composed of an infrared radiation thermometer. The position detection unit 8 is composed of a CCD camera 8a for capturing an image of the joint portion Ha and an illumination unit 8b for illuminating an imaged portion.

In the coil 6, as shown in FIG. 3, a square-shaped heating conductor 11 is attached to each of the tips of a pair of coil conductors 10 arranged in parallel. Heating conductor 1
1 and 11 are arranged parallel to each other in a vertical direction. The base end of the heating conductor 1111, that is, the end portion on the coil conductor 10 side is connected by the bridge conductor 12. Therefore, the bridging conductor 12 and the heating conductor 11,
The coil 6 constituted by 11 has an opening 6a on the tip side.
It has a U-shape in plan view. Further, the central portion in the longitudinal direction of the bridging conductor 12 is bent downward to form the guide groove 13 on the upper surface thereof. The tip 3a of the brazing filler metal supply part 3 is inserted into the guide groove 13 from the coil conductor 10 side, and the tip 3a of the brazing filler metal supply part 3 inserted in the guide groove 13 in this manner is the heating conductor 11. It is designed to be installed up to the center of the height direction. In addition, the infrared ray incoming / outgoing optical path R of the temperature detecting section 7 is also arranged along the guide groove 13, and the brazing filler metal supplying section 3
The temperature of the tip 3a, that is, the temperature of the joint portion Ha can be measured. In addition, in the present embodiment, the guide groove 13 constitutes an introducing portion.

The space surrounded by the square-shaped heating conductors 11 is filled with a core 14 made of ferrite, and the upper and lower surfaces of the bridging conductor 12 are substantially covered with a core 15 made of ferrite. There is.
These cores 14 and 15 have the function of concentrating the magnetic flux generated by the coil 6 inside the two heating conductors 11 and 11 in the facing direction.

The heating conductors 11 and 11 and the bridging conductor 12 are hollow and communicate with each other. The heating conductors 11 and 11 and the bridging conductor 12 have cooling water from a cooling water supply source (not shown). By supplying
The coil 6 is designed to be cooled. An insulator 16 is interposed between the coil conductors 10 to keep the coil conductors 10 and 10 insulated.

The overall structure of this automatic brazing device will be described with reference to the block diagram of FIG. The main controller 5 includes a main controller 20, a high frequency heating controller 21, and a brazing controller 22. The main control unit 20 supplies the 6-axis manipulator 2 and the brazing filler metal based on the position information of the 6-axis manipulator 2 sent from the manipulator controller 4 and the position information of the brazing filler metal supply unit tip 3a sent from the position detecting unit 8. The detection operation of the relative positional relationship of the tip 3a of the part is controlled. In addition, the main control unit 2
0 also controls the temperature detection operation of the temperature detection unit 7.

The high frequency heating controller 21 is a main controller 2
An instruction from 0 controls the high frequency induction heating operation by the coil 6. The brazing control unit 22 controls the brazing timing and the brazing material L supply operation according to an instruction from the main control unit 20.

Next, the brazing work by this automatic brazing device will be described. When a pallet (not shown) having a connected body H composed of a pair of pipes arranged in abutting relation is loaded in front of the automatic brazing device, the 6-axis manipulator 2 is set by the manipulator controller 4 in advance. The coil 6 is moved to the determined three-dimensional position detection position. At this time, the coil 6 approaches the connected body H from the outside in the radial direction of the connected body H, then overlaps with the connected body H through the opening 6a, and finally surrounds the periphery of the connected body H. Will be placed. Since the coil 6 is arranged so as to surround the connected body H in this manner, the coil 6 can be arranged even in the connected body H in which the both ends are connected to other members and are in an unopened state. .

After detecting the relative three-dimensional position between the coil 6 and the body H to be connected by the position detector 8, the position of the coil 6 is corrected to the position surrounding the body H to be connected based on the detection result. To move. For position detection at this time, a known three-dimensional position recognition method such as a stereo method is used.

When the position detection is completed, the position of the joint portion Ha is corrected based on the detection result. The position correction is performed by slightly moving the coil 6 in the XYZ directions by the 6-axis manipulator 2. As shown in FIG. 5, the connected body H and the coil 6 in which the position of the joint portion Ha is corrected are as follows: a = b = c a: One heating conductor 11 and the connected body H Separation distance b: Separation distance between the other heating conductor 11 and the connected body H c: Separation distance between the bridge conductor 12 and the connected body H is maintained. At this time, the tip 3a of the brazing filler metal supply part 3 is arranged near the joint part Ha of the body H to be connected.

The position where a = b = c is the optimum position for induction heating for the following reason. That is,
The induction heating force of the coil 6 becomes weaker as it is farther from the heating conductors 11 and 11 and the bridging conductor 12, and becomes stronger as it approaches. Therefore, when heating the connected body H, the connected body H
Is not in the center of the coil 6, for example, if a: b = 1: 4 and the body H to be connected is biased toward the one heating conductor 11 side, local heating occurs and one heating conductor 11 Melting will occur on the side surface of the adjacent connected body H. Therefore, the position of a = b = c at which the unevenness of heating does not occur is the optimum position for induction heating.

After positioning the body H to be connected, the brazing material L is supplied from the tip 3a of the brazing material supply section 3 to the joint portion Ha of the body H to be connected. At this time, the tip 3 of the brazing filler metal supply section 3
a is the guide groove 1 provided in the coil 6 as described above.
3, the linear brazing filler metal L can be supplied to the joint portion Ha from the radial outside of the connected body H, as shown in FIG. It is like this. Thus, the connected body H
Since the brazing material L can be supplied from the outer side in the radial direction of
Even in the connected body H whose both ends are not opened, the linear brazing material L can be supplied to the joint portion Ha.

While supplying the brazing filler metal L, the temperature detecting section 7
The temperature of the joint portion Ha is measured by. Temperature detector 7
As shown in FIG. 6, the temperature of the joint portion Ha is detected by
This is possible because the guide groove 13 secures the infrared ray outgoing / incident optical path R between the temperature detecting portion 7 and the joint portion Ha. Then, based on the temperature detection result of the temperature detection unit 7, while controlling the heating condition by the coil 6, the supply of the brazing material L from the brazing material supply unit 3 is continued.

FIG. 7 shows how the coil 6 is heated by this automatic brazing device (surface temperature of the joint portion Ha of the body H to be connected).
7A shows the temperature change of the joint portion Ha with time, and FIG. 7B shows the control condition of the coil output according to the temperature change. . Figure 7
In (a), LEV3 is a brazing filler metal supply temperature (for example,
780 ° C. when phosphorus copper braze BCUP3 is used as the brazing filler metal L, and LEVl and LEV2 indicate the upper limit value and the lower limit value of the temperature control for keeping the temperature of the joint portion Ha at LEV3, respectively. Then, the joint portion Ha
When the temperature rises to LEV1, the coil output is reduced to 30% of the total output. When the temperature at the brazing position drops to LEV2, the coil output will be 50% of the total output.
Up to. Note that LEV4 is a limit value for preventing melting of the connected body H, and when the surface temperature of the joint portion Ha reaches LEV4, the output to the coil 6 is completely stopped for safety.

The coil 6 is 100% for 1 second from the start of heating.
After heating the connection target H with the output of 1), the connection target H is heated until it reaches LEV1 with the output reduced to 70%. The reason for controlling heating in this way is as follows. That is, by efficiently heating in a short time using a large output, only the joint portion Ha is locally heated, thereby preventing the brazing filler metal L from flowing too much, and thus achieving an optimum fillet shape (melting degree of the brazing filler metal L). ) Is available for brazing. Moreover, even if the output of the coil 6 is reduced by detecting the first overshoot (the surface temperature of the joint portion Ha reaches LEV3) by reducing the output to 70% on the way, the temperature of the joint portion Ha is preheated. Further rises above LEV3).

In this way, while controlling the surface temperature of the joint portion Ha to LEV3, the brazing unit 22 supplies a predetermined amount of brazing material L to the joint portion Ha by the brazing unit 1.

The control results shown in FIG. 7 are obtained under the following conditions.

・ Connected object H: 3/8 steel pipe ・ a = b = c = 2 mm ・ High frequency: 16 KHz, maximum output: 3 OKW After the brazing material L is supplied and brazing work is completed in this way, When the 6-axis manipulator 2 returns to its original position and the pallet having the brazed connected body H mounted thereon is carried out, a series of brazing operations is completed.

Thus, in this automatic brazing device,
The heating control is performed with high accuracy by feeding back the measurement of the heating temperature, and therefore, the inconvenience of melting the connected body H does not occur. Further, by forming the coil 6 in a U shape in a plan view, it is possible to braze the connected body H whose both ends are not opened.

By the way, in the above-mentioned embodiment, the introduction portion is constituted by the guide groove 13 formed in the coil 6, but as shown in FIG. 8, the introduction portion may be constituted by the guide cylinder 30. That is, this automatic brazing apparatus is configured such that the heating conductors 1 arranged in parallel are opposed to each other in the vertical direction.
The base ends of 1 and 11 (ends on the coil conductor 10 side) are connected by a flat bridging conductor 31 which is not bent. The guide cylinder 30 is arranged on the upper surface of the bridge conductor 31. The guide cylinder 30 is arranged such that one end of the guide cylinder 30 faces the central portion of the space formed between the heating conductors 11 and the other end faces the coil conductor 10. Further, the guide cylinder 30 has an inner diameter into which the tip 3a of the brazing filler metal supply part 3 can be inserted.

The tip 3a of the brazing filler metal supply part 3 is inserted into the guide cylinder 30 from the coil conductor 10 side, and the tip of the brazing filler metal supply part 3 thus inserted into the guide cylinder 30. 3a is introduced and arranged up to the central portion in the height direction of the heating conductors 11, 11. Further, the infrared ray incident / incident light path R of the temperature detecting section 7 is arranged along the upper end surface of the guide tube 31, and measures the temperature of the tip 3a of the brazing filler metal supplying section 3, that is, the joint portion Ha. You can do it.

Next, an embodiment in which the position correcting operation of the coil 6 is further simplified will be described. As shown in FIG. 9, this automatic brazing device is characterized in that the brazing unit 1 is attached to the 6-axis manipulator 2 via a horizontal slide mechanism 40. The horizontal slide mechanism 40 includes the base 4
0a and a slide portion 40b attached to the base portion 40a so as to be freely movable in the horizontal direction.
0a is fixed to the tip of the 6-axis manipulator 2, while the brazing unit 1 is attached to the slide portion 40b. By interposing such a slide mechanism 40, the position of the coil 6 can be corrected without performing the complicated operation of detecting the position of the coil 6 and moving the coil 6 based on the detection result. That is, when high frequency induction heating is performed, a repulsive force or a suction force is generated between the connected body H and the coil 6. Therefore, if this force is used, the relative positional relationship between the connected body H and the coil 6 is a =
The position can be corrected to the relationship of b = c (see FIG. 6).

This will be described below. First, the force relationship between the coil 6 and the body H to be connected by high frequency heating will be described. When the connected body H is made of a material having a low magnetic permeability such as copper or aluminum, as shown in FIG. When it shifts to the side, the repulsive force acting on one heating conductor 11 becomes larger than the repulsive force acting on the other heating conductor 11. At this time, a suction force is also generated, but since the connected body H has a low magnetic permeability, the suction force is small and has almost no influence. Therefore, due to the repulsive force that is generated, a synthetic force that pushes the coil 6 toward the one heating conductor 11 side is generated.
In this embodiment, as shown in FIG. 10B, the slide mechanism 40 automatically moves the coil 6 to a position where the repulsive forces are balanced by the generated combined force. Can be heated uniformly. Further, the movement error caused by the 6-axis manipulator 2 can be corrected by the slide mechanism 40.

As shown by the phantom line in FIG. 9, if another slide mechanism 41 for moving the coil 6 in the direction orthogonal to the slide mechanism 40 is provided to enable the slide movement in the XY2 directions, By applying to the annular coil 70 described in the conventional example, the relative position between the annular coil 70 and the joint portion Ha can be automatically corrected.

Next, another embodiment in which the position correction operation of the coil position (brazing position) is simplified will be described. As shown in FIG. 11, this automatic brazing device is characterized in that the brazing unit 1 is attached to the 6-axis manipulator 2 via a rotating mechanism 45. Rotating mechanism 45
Is an annular base portion 45a and a rotating portion 4 rotatably mounted inside the base portion 45a via a bearing portion 45b.
5c, the base portion 45a is fixed to the tip of the 6-axis manipulator 2, and the brazing unit 1 is attached to the rotating portion 45c.

This rotating mechanism 45 is constructed by the above-mentioned a = b = c.
Instead of maintaining the position (see FIG. 6), the deviation of the orientation of the arrangement of the coil 6 and the connected body H is corrected. That is, as shown in FIG. 12 (a), when the coil 6 having a certain width (h in FIG. 12) is used to braze the connected body H made of a low magnetic permeability material, the width h Of the coil 6 along the line and the connected object H
When the connected body H is tilted with respect to the coil 6 due to a deviation from the axial direction of, the balance of the repulsive force is lost between the connected body H and the coil 6, and a force in the rotational direction acts. Therefore, FIG.
When the rotating mechanism 45 shown in FIG. 12 is provided, as shown in FIG. 12B, the rotating mechanism 45 reaches a position where the repulsive force is balanced by the rotational force generated between the coil 1 and the connected body H.
Rotates to automatically correct the position of the coil 6, so that the connected body H is uniformly heated by the coil 6. Further, the rotation mechanism 45 can also correct the movement error caused by the 6-axis manipulator 2.

In each of the other embodiments described above, it is premised that the connected body H made of a material having a low magnetic permeability is brazed, but when the connected body H has a high magnetic permeability such as iron. As shown in FIGS. 14 (a) and 15 (a), the suction force becomes larger than the repulsive force, so that it cannot be performed. Therefore, when the material of the connected body H has a high magnetic permeability such as iron, a 6-axis force sensor 50 is interposed between the coil 6 and the 6-axis manipulator 2 as shown in FIG. The 6-axis force sensor 50 detects the suction force generated between the body H and the coil 6, and the 6-axis manipulator 2 moves the coil 6 to a position where the detected suction force is uniform. That is, FIG. 14 (b) and FIG.
Uniform heating can be performed by moving or rotating the coil 6 to a position where the combined force becomes 0 (the suction force is balanced) as shown in FIG.

The 6-axis force sensor 50 can also be used in brazing the connected body H made of a material having a low magnetic permeability. In this case, the 6-axis force sensor 5 is used without using the slide mechanism 40 and the rotation mechanism 45 shown in FIGS. 9 and 11.
The coil 6 may be moved or rotated by a moving mechanism such as the 6-axis manipulator 2 to a position where the repulsive forces measured at 0 are balanced.

[0041]

As described above, according to the present invention, the following effects can be obtained.

Advantages of Claims 1 to 4 Automatic brazing of a connected body having a structure in which automatic brazing is not possible (both ends are connected and not open) can be realized, and temperature control of brazing is possible. I was able to increase the accuracy by breaking it in.

Effects of Claims 5 to 8 The relative positions of the body to be connected and the coil can be corrected to an optimum position for brazing, and the brazing precision can be further improved by that amount. Furthermore, since such position correction can be realized with a simple configuration, the increase in the manufacturing cost of the device can be suppressed to the minimum even though the brazing accuracy is increased.

The effect of claim 9 The relative position of the body to be connected and the coil can be corrected to the optimum position for brazing, and the brazing accuracy can be further improved by that amount.

[Brief description of drawings]

FIG. 1 is a front view showing the overall structure of an automatic brazing device according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a main part of one embodiment.

3A and 3B are diagrams for explaining the main part of one embodiment in more detail, where FIG. 3A is a front view, FIG. 3B is a plan view, and FIG. 3C is a sectional view taken along line AA of FIG. 3B. , (D) is a side view

FIG. 4 is a block diagram showing an outline of a system according to an embodiment.

FIG. 5 is a plan view showing an optimum positional relationship between a coil and a body to be connected.

FIG. 6 is an enlarged front view of a main part of the embodiment.

FIG. 7 is a diagram showing the condition of heating control during brazing according to the present invention.

8A and 8B are views showing a main part of another embodiment of the present invention, in which FIG. 8A is a plan view and FIG. 8B is a sectional view taken along line BB in FIG. 8A. Yes, the figure (c) is a side view.

FIG. 9 is a perspective view showing a main part of still another embodiment of the present invention.

10 is a view for explaining the positional relationship between the coil and the body to be connected in the automatic brazing device of FIG. 9, and FIG.
The case where the connected body is out of the optimum heating position is shown, and the figure (b) shows the case where the connected body is in the optimum heating position.

FIG. 11 is a perspective view showing a main part of still another embodiment of the present invention.

FIG. 12 is a view for explaining the positional relationship between the coil and the body to be connected in the automatic brazing device of FIG. 11, and FIG. 12 (a) shows the case where the body to be connected is out of the optimum heating position. FIG. 6B shows the case where the connected body is in the optimum heating position.

FIG. 13 is a front view showing a main part of still another embodiment of the present invention.

FIG. 14 is a diagram for explaining the positional relationship between the coil and the connected body in the automatic brazing device of FIG. 13, and FIG. 14 (a) shows the case where the connected body is out of the optimum heating position. FIG. 6B shows the case where the connected body is in the optimum heating position.

FIG. 15 is a view for explaining the positional relationship between the coil and the connected body in the automatic brazing device of FIG. 13, and FIG. 15 (a) shows the case where the connected body is out of the optimum heating position. FIG. 6B shows the case where the connected body is in the optimum heating position.

FIG. 16 is a perspective view showing a main part of a conventional brazing device.

[Explanation of symbols]

 3 Brazing material supply part 6 Coil 7 Temperature detection part 13 Guide groove 30 Guide tube H Connected object Ha Joint part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Lee Fan Tech 22-22 Nagaike-cho, Abeno-ku, Osaka, Osaka Prefecture

Claims (9)

[Claims] 1. A coil for inductively heating a joint portion of at least a pair of objects to be connected in abutting relation, wherein the coil is inserted through the object to be connected in a direction orthogonal to a direction in which the objects to be connected are abutted. An automatic brazing device having a U-shape with a possible opening. 2. A coil which surrounds and surrounds the joint portions of at least a pair of objects to be connected, which are arranged in abutting relation, for induction heating, a brazing filler metal supplying portion for supplying a brazing filler metal to the joint portions, and a temperature for the joint portions. A temperature detecting unit for measuring, and the coil has a leading end of the brazing filler metal supplying unit and / or an introducing unit for guiding the temperature detecting unit from the outside of the coil to the joint portion. Automatic brazing device. 3. The groove is provided in the coil so that the outside and the inside of the coil communicate with each other along a direction orthogonal to the abutting direction of the objects to be connected. Automatic brazing device. 4. The lead-in portion allows the tip of the brazing filler metal supply portion and / or the temperature detecting portion to be inserted therethrough, and connects the outer side and the inner side of the coil along a direction orthogonal to the butting direction of the objects to be connected. 3. The automatic brazing device according to claim 2, wherein the automatic brazing device is a cylinder attached to the coil. 5. A coil that surrounds the joint portions of at least a pair of connected bodies that are arranged in abutting relationship and that performs induction heating, and is driven by a repulsive force that acts between the connected body and each position of the coil, An automatic brazing device, comprising: a position correction mechanism that moves the coil to a position where the repulsive force is balanced. 6. The automatic brazing device according to claim 5, wherein the position correcting mechanism slides the coil along a direction orthogonal to the butting direction of the objects to be connected. 7. The automatic brazing device according to claim 6, wherein the position correcting mechanism slides the coil along each of two orthogonal directions. 8. The automatic brazing device according to claim 5, wherein the position correction mechanism is for rotating the coil around the direction in which the objects to be connected are butted. 9. A coil for inducing heating around a joint portion of a connected body, and a measuring mechanism for measuring a repulsive force or a suction force acting between the connected body and each position of the coil, An automatic brazing device comprising: a moving mechanism that moves the coil to a position where the repulsive force or the suction force measured by the measuring mechanism balances each other.