JPH11214141A - Heating coil structure for high frequency brazing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly perform the high frequency heating to both pipes when the pipes of different diameters are connected and to perform the superior brazing without deteriorating the strength of the pipes by forming a heating part of a heating coil into the shape of a horseshoe truncated chevron so that it approaches a small diameter side at both sides of the end parts to be connected of the metallic pipes. SOLUTION: In the heating coil structure of high frequency brazing, the high frequency is generated on a horseshoe truncated chevron-shaped coil 4 by the electromagnetic induction, the end parts of the pipes 2, 3 of different outer diameters, that is, the pipes of small and large diameters are located on a heating part of the heating coil 4, and both pipes are heated with high frequency to perform brazing. On this occasion, the shape of the heating part of the heating coil 4 is formed into the shape of a horseshoe truncated chevron, so that it approaches the small diameter side of the both sides of the end parts to be connected of the metallic pipes 2, 3, whereby the magnetic permeability to the larger diameter pipe 3 and the small diameter pipe 2 is made constant to uniformly perform high frequency heating to a ring-shaped brazing material 1 on both pipes 2, 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for generating a high frequency wave in a heating coil by electromagnetic induction, positioning the ends of metal pipes having different outer diameters in a heating portion of the heating coil, and performing high frequency heating. The present invention relates to a heating coil structure for mounting.

[0002]

2. Description of the Related Art As shown in FIG. 3, a conventional heating coil structure for high-frequency brazing is a parallel heating coil 5 having a heating section space in the middle, and metal pipes 2 having different outer diameters. 3 is positioned in the heating section space, the ring-shaped brazing material 1 is fitted to the small-diameter pipe 2, and the ends of both pipes 2 and 3 are brazed to each other by high-frequency heating.

[0003]

However, the degree of approach of the heating portion of the heating coil 5 to each pipe is as follows.
It is narrow between the large diameter pipes 3 and wide between the small diameter pipes 2. Therefore, when high-frequency heating is performed in a state close to the large-diameter pipe 3, the effect of brazing to the small-diameter pipe 2 is poor, and the airtightness of the brazed portion is poor. Then, in order to improve the brazing condition, it is conceivable to lengthen the heating time to some extent. However, in this case, there is a disadvantage that the strength of the pipe itself is deteriorated.

The present invention has been made based on the above circumstances, and even when connecting pipes of different diameters, high-frequency heating can be performed equally between them, and good brazing can be performed without deteriorating the strength of the pipes. An object of the present invention is to provide a heating coil structure for high-frequency brazing that can be realized.

[0005]

Therefore, in the present invention,
In the heating coil structure for generating a high frequency in the heating coil by electromagnetic induction and positioning the ends of metal pipes having different outer diameters in the heating portion of the heating coil, performing high-frequency heating and brazing, The shape of the heating portion of the heating coil is formed in a horseshoe shape so as to approach on the small diameter side on both sides of the connected end of the metal pipe.

In this case, in the heating coil, a heating portion is formed in an intermediate portion of the coil, between which the connected end of the metal pipe is located. It is preferable that the heating coil is relatively rotated around a heating section, and the connected end of the metal pipe in the heating section is uniformly heated.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to FIGS. The heating coil structure for high frequency brazing shown here generates a high frequency in the heating coil 4 by electromagnetic induction, and the heating coil 4
In the heating section, the ends of the metal pipes 2 and 3 having different outer diameters are located, and high-frequency heating and brazing are performed.
In the present invention, the shape of the heating portion of the heating coil 4 is formed in a horseshoe shape so as to approach on the small diameter side on both sides of the connected end portions of the metal pipes 2 and 3, and has a ring shape. The high frequency heating of the brazing material 1 can be uniformly performed on both the pipes 2 and 3.

In this embodiment, the heating coil 4
Has a heating portion (space) formed in the middle thereof, between which the connected ends of the metal pipes 2 and 3 are located. This heating portion is connected to one end of two heating coils facing each other. Department. Further, the heating coil 4 and the metal pipes 2 and 3 are relatively rotated around the heating portion (space) of the heating coil 4 (for example, the metal pipes 2 and 3).
May be rotated about its vertical axis) to uniformly heat the connected ends of the metal pipes 2 and 3 in the heating section.

As described above, when a suitable high-frequency generator generates electromagnetic induction in the heating coil to heat the metal pipes 2 and 3 having greatly different outer diameters, to melt and connect the brazing material 1, In order to provide the horseshoe-shaped C-shaped heating coil 4, the gap between the small-diameter pipe 2 and the heating section of the heating coil 4 and the gap between the large-diameter pipe 3 and the heating section are equalized to achieve the same. The small-diameter pipe 2 and the large-diameter pipe 3 generate heat uniformly and generate heat. For this reason, the permeability and airtightness of the brazing material 1 at the connected end are improved as compared with the related art. In addition, the use of the horseshoe-shaped C-shaped heating coil 4 makes it possible to shorten the heating time,
Deterioration of pipe strength due to heating can be kept low.

[0010]

According to the present invention, as described in detail above, by making the heating coil into a horseshoe-shaped C-shape, the permeability to the large-diameter pipe and the small-diameter pipe is made constant, so that the metal pipe can be evenly distributed. High-frequency heating can be performed, and the brazing material can flow into the metal pipe, and the airtightness thereof can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a front view showing a main part.

FIG. 3 is a front view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ring low material 2 Small diameter pipe 3 Large diameter pipe 4 Horseshoe-shaped C-shaped heating coil 5 Parallel coil

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] January 22, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

Therefore, in the present invention,
In the heating coil structure for generating a high frequency in the heating coil by electromagnetic induction and positioning the ends of metal pipes having different outer diameters in the heating portion of the heating coil, performing high-frequency heating and brazing, On both sides of the connected end of the metal pipe, so as to intersect with the axis of the metal pipe
Arranging the axis of the heating coil, the metal pie
The shape of the heating portion of the heating coil is formed in a horseshoe shape so that the turn of the heating coil approaches on the small diameter side of the loop.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

In this case, in the heating coil, a heating portion is formed in an intermediate portion of the coil, between which the connected end of the metal pipe is located. And fixed the metal pipe
In the state, the heating coil is moved to the center of the metal pipe,
It is preferable that the connected end of the metal pipe in the heating section is uniformly heated.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to FIGS. The heating coil structure for high frequency brazing shown here generates a high frequency in the heating coil 4 by electromagnetic induction, and the heating coil 4
In the heating section, the ends of the metal pipes 2 and 3 having different outer diameters are located, and high-frequency heating and brazing are performed.
In the present invention, both sides of the connected end portions of the metal pipes 2 and 3 intersect with the axes of the metal pipes 2 and 3 as illustrated.
When the axis of the heating coil 4 is arranged so as to be
In addition, the heating core is placed on the small diameter side of the metal pipes 2 and 3.
The shape of the heating portion of the heating coil 4 is formed in a horseshoe-shaped C-shape so that the turns of the ill 4 are close to each other. There is a device that can be done.

Claims (3)

[Claims] 1. A heating coil for generating high-frequency waves by electromagnetic induction, and heating the high-frequency heating and brazing by locating the ends of metal pipes having different outer diameters in the heating section of the heating coil. In the coil structure, the shape of the heating portion of the heating coil is formed in a horseshoe shape so as to approach on the small diameter side on both sides of the connected end of the metal pipe. Heating coil structure for mounting. 2. The high-frequency device according to claim 1, wherein the heating coil has a heating portion formed at an intermediate portion of the coil, and a connected end portion of the metal pipe is located between the heating portions. Brazing heating coil structure. 3. The heating coil and the metal pipe are relatively rotated about a heating portion of the heating coil,
The heating coil structure for high-frequency brazing according to claim 1 or 2, wherein the connected end of the metal pipe in the heating section is uniformly heated.