JPH07142268A - High frequency induction heating transformer - Google Patents

Abstract

PURPOSE:To reduce power transmission loss between coils, and facilitate maintenance, inspection and repair, by accommodating a primary coil in a secondary coil via an insulating layer, and making a spiral copper tube the primary coil as the path of a primary current which tube serves as a path of cooling medium. CONSTITUTION:A secondary coil 1 is formed by integrating a copper stand part provided with holes for circulating cooling medium, with a secondary winding part whose inner diameter is equal to the maximum value within the maximum allowable outer diameter of a main transformer and electrical conditions. A primary coil 2 is formed by winding a small diameter copper tube in a spiral type in which tube cooling medium can be made to flow. The outer diameter of the spiral is determined by the allowable maximum value of the secondary winding part structure and electrical insulation. The primary coil 2 is accommodated in the secondary winding part via an insulating part 3, and is wrapped with resin excellent in high frequency characteristics and electrical insulation. Port part copper tubes 25, 26 of the primary coil are fixed to a fixing plate 31 of insulator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention applies a high frequency high voltage to a primary coil to generate a high frequency low voltage in a secondary coil, so that an eddy current is generated in an object to be heated enclosed in an insertion hole of an inductor block. The present invention relates to a transformer that generates heat by generating loss and hysteresis loss, and is particularly effective for a device that seals a metal stud to a panel of a color cathode ray tube.

[0002]

2. Description of the Related Art As a technique of this type, Japanese Examined Patent Publication No.
The following two examples are known as prior art such as those disclosed in No. 04.

(1) A concentric circular double-tube structure is adopted as the secondary coil, and a cooling medium is flowed in the void portion of the double tube to cool it. The portion corresponding to the fixed base of the inductor block, which is called "copper base" in the present invention, is extremely small. The cooling of the heat of the fixed base portion due to the heat generation of the inductor block is indirectly performed by the cooling medium in the void of the double pipe structure. The primary coil is formed by spirally winding a hollow copper tube and housed in the inner tube of the double tube structure.

(2) As a secondary coil, a rectangular parallelepiped copper ingot is machined to provide a cylindrical space, in which a primary coil similar to the above example is housed, molded with resin and fixed. There is. The copper mass of the secondary coil is further provided with a plurality of holes,
The path is through the cooling medium. This copper ingot is not only a secondary winding but also functions as a pedestal for fixing the inductor block. Due to this structural condition, the cooling surface has a considerably large heat capacity, but is considerably heavy.

The features of the above two examples are: In both cases, a hollow copper tube wound in a spiral shape is used as a primary coil, and a cooling medium is caused to flow in the copper tube for cooling. 2. Although the shape and structure are different, it is a secondary coil that wraps the primary coil in a concentric shape. 3. The primary and secondary coils are completely separate and independent,
In addition, since a sufficient insulation distance is maintained, there is little risk of sparking even if the secondary coil is grounded for safety reasons. 4. Since the primary coil and the secondary coil can be cooled by separate systems, cooling can be effectively performed.

[0006]

However, the above-mentioned conventional transformer has the following problems. 1. The structure is complicated and processing / manufacturing is not easy.

2. The outer diameter of the primary coil is restricted by the shape and inner diameter of the secondary winding portion of the secondary coil, so that the power transfer rate from the primary coil to the secondary coil is low and the loss is low. Is big.

3. Maintenance is difficult for both the primary coil and the secondary coil such as repair when the cooling lead copper tube is broken.

In order to improve the power transfer rate from the primary coil to the secondary coil, the inventors of the present invention can easily process and manufacture the high frequency induction heating transformer with a simple structure.
The present invention has been completed by researching each of the configurations to facilitate maintenance and repair.

That is, the present invention has been made in view of the above-mentioned drawbacks of the prior art, and can be easily processed and manufactured with a simple structure to reduce the power transmission loss from the primary coil to the secondary coil. It is an object of the present invention to provide a high-frequency induction heating transformer that can be easily inspected and repaired.

[0011]

In order to achieve the above object, a high frequency induction heating transformer according to the present invention has a copper base portion provided with a hole for circulating a cooling medium and a maximum allowable outer size limit of the transformer. The secondary coil is formed by integrally mounting the secondary winding part of a single cylindrical copper plate or copper tube whose outer diameter is increased up to the maximum size allowed by electrical conditions. A small diameter copper tube that can be made to flow is wound in a spiral shape, and the outer diameter is wound to the maximum size allowed for the structure and electrical insulation of the secondary winding part. The secondary coil is housed inside the secondary winding through an insulator, and the primary coil is wrapped with an insulating resin having good high-frequency characteristics, and the primary coil outlet copper tube is also insulated. It is characterized by fixing with a fixing plate of It is intended.

[0012]

With the above structure, the copper base portion, the cylindrical secondary coil, and the inductor block are sufficiently cooled, and have an extremely simple structure, which simplifies processing and manufacturing. In addition, the secondary coil is formed concentrically with the primary coil wound to the maximum outer diameter under the constraint of the inner diameter of the secondary winding part while ensuring the required insulation. The mutual inductance between them can be maximized in a limited space.
As a result, it is possible to improve the heating efficiency and to extremely facilitate maintenance and repair such as replacement of the primary coil and replacement of the copper pipe for cooling the copper stand of the secondary coil.

[0013]

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

In FIGS. 1 and 2, reference numeral 1 is a secondary coil having a single tube structure for heating by an induced current, and 2 is mounted in the secondary coil 1 through an insulating layer 3 to apply an induced current to the secondary coil 1. It is a primary coil to be generated. Reference numerals 4 and 14 (FIG. 4) are copper bases integrally attached to the cylindrical secondary winding portion 13 to form the secondary coil 1, and the transformer A is constituted by these copper bases.

In order to attach this transformer to the transformer feed plate of the stud sealing device, the base 5 shown in FIGS. 1, 4 and 5 is attached to the secondary coil copper bases 4, 1 by the side plates 6 and 7.
4, the front plate 8 and the back plate 9 are attached, and the primary coil 2 is fixed to complete the process. The base 5 is made by processing a thick plate of an insulator in order to electrically insulate it from the transformer feed plate. The side plates 6 and 7 are made of a copper plate in consideration of strength and cooling, and the fixed portion of the base is bent into an L shape and fixed by screws from the lower portion of the base. Front plate 8
And the back plate 9 is made of a plate of an insulating material in order to secure the gap between the secondary coils electrically and structurally.
14 and the base 5 are attached by screws. Since the fixing screw from the transformer feed plate is too long between the side plates 6 and 7 and the base 5, a thin insulating material is used so that the copper side plates 6 and 7 are not contacted and the electrical insulation is not damaged. Spacer 1
0 and 11 are sandwiched.

The insulating layer 3 is made of a high withstand voltage such as a Teflon (trade name: DuPont) sheet, and both ends of the insulating layer 3 are in the gap 12 between the copper bases 4 and 14 while enclosing the primary coil 2. The secondary winding portion 13 is integrally formed by hard brazing or the like so that the upper portion of the copper tube is cut off around the entire circumference so that a predetermined gap 12 is maintained under the copper bases 4 and 14. As shown in FIG. 2, holes 15 and 16 are opened in the copper bases 4 and 14, respectively, and in places where they do not penetrate to the facing side, holes are opened in the lower part of the copper base such as 17 and 18, respectively, to connect the water-passing copper The pipe 19 is attached with a hard braze, and a water passage such as 15-19-16 is created. PT screws 20 and 21 for water joints are formed in the openings of the water passage holes 15 and 16, respectively, and a dedicated water joint is attached to the water joint and a predetermined copper pipe is connected to the inlet of the cooling medium. And take the exit. The copper pipe 19 for water flow connection is bent so that the outer circumference is the same as the outer circumference of the secondary winding portion 13, and electrically becomes a part of the secondary winding and contacts the secondary winding portion 13. It also has an effect on its cooling.

FIG. 7 is a plan view of the primary coil 2. The primary coil 2 is formed by spirally winding a copper tube 22 and winding end portions 23, 2
The connecting copper pipes 25 and 26 are brazed to the wire 4 and are projected in either direction of the winding ends (23 in the figure). The outer diameters of the output copper pipes 25 and 26 can be changed according to the outer diameter of the connection for the cooling medium of the device used for this transformer. The tube 22 may be extended and projected as it is. Insulation tape such as Teflon (trade name) sheet between each winding of the primary coil 2
7, 28, 29 and 27 (not shown in the figure) are provided on the opposite side of 27 so as to alternately pass the outside and the inside of the winding so as to secure a distance necessary for insulation between the windings.
In this figure, the number of tapes used and their intervals are 4 and 9
The angle is 0 °, but it is sufficient if the required insulation is ensured. The primary coil is entirely impregnated with a silicone resin-like material, and the mechanical strength of the resin is increased by hardening the resin to improve vibration resistance and insulation due to dew condensation that accompanies the water cooling method. Insulation is reinforced including prevention of deterioration of yield strength.

As shown in FIG. 6, the primary coil 2 is wrapped in the insulating layer 3 and housed in the secondary winding portion 13, and penetrates the primary coil lead-out fixing plate 31 made of an insulating material, and the back plate 9 And penetrate to the outside. The fixing plate 31 is provided with a hole through which the primary coil outlet copper pipes 25 and 26 penetrate, and the surface on the side of the back plate 9 is provided with a conical recess such as 32 and 32 'around the through hole. The rear plate 9 is also provided with a hole through which the primary coil lead-out copper pipes 25, 26 penetrate, and the face on the lead-out fixing plate 31 side is similarly dented into a conical shape 33, 33 'around the hole. Has been applied. Adhesive is filled in both of the dents, and the primary coil outlet copper pipes 25, 2
6 is adhered and fixed to the lead-out plate 31 and the back plate 9 with an adhesive. The back plate 9 and the lead-out plate 31 are adhesively fixed with an adhesive and screws. As shown in FIG. 3, the primary coil lead-out fixing plate 31 has two corners such as 34 and 34 '.
The lead wire fixing plate 31 is cut so as to be in close contact with the inner circumference of the secondary winding portion 13, the lead fixing plate 31 is fitted to the inner circumference of the secondary winding portion 13, and the fixing of the lead portion is reinforced by the secondary winding portion 13. ing.

FIG. 8 compares the state of mutual inductance and current distribution depending on the structure-shape for three methods of (A) the present invention, (B) double tube structure, and (C) copper ingot processing. It is assumed that the outer shape of the transformer, the pipe diameter φ of the primary coil 40, and the distance D between the primary coil 40 and the secondary coil 41 are the same.

From the outer shape of the transformer and the structure and shape of the secondary coil winding part, the outer diameter of the secondary winding part is the largest (C), and (A),
Although (B) is the same, (A) has the largest inner diameter of the secondary winding portion, and (A) has the largest outer diameter of the primary coil because D is the same, and the mutual inductance value also has the maximum value. Further, in all three systems, the primary coil and the secondary coil are arranged concentrically, so that the distribution of the secondary current in the secondary coil winding portion is best in the case of (A).

As described above, it is clear that the method (A) of the present invention maximizes the mutual inductance between the primary coil and the secondary coil, and the experimental results are also in agreement.
Therefore, the present invention has a high economical efficiency and a minimum power loss when the stud is sealed.

[0022]

As described above, the present invention is an extremely effective technique for the stud sealing process, which solves the problems that cannot be solved by the prior art while making the most of the prior art. Secondary coil winding part is JIS H3
Since a copper tube specified by 300, H3320, etc. can be easily processed by processing it into a material, the manufacturing process is extremely simple as compared with the prior art. The structure is extremely simple as described above.

Regarding the electrical performance, as shown and described in FIG. 8, the mutual inductance value is excellent, and it is a high-efficiency transformer, which contributes to power saving in the stud sealing process. The lighter weight also makes it easier to control the movement of the transformer feed plate during stud sealing, which also contributes to the accuracy of stud sealing. Regarding maintenance and repair, the most common damage is the copper pipe for cooling the primary coil and the secondary coil, but in the case of the conventional technology, almost no repair is possible.
I had to deal with it by exchanging it. In the case of the double tube system, the entire primary coil could be replaced only when the primary coil was damaged. For copper ingot processing,
Even if the cooling lead of either the primary coil or the secondary coil is damaged, the whole will be replaced. 2 in the case of the present invention
If the cooling outlet on the secondary coil side is damaged, only the pipe damaged at the water joint needs to be replaced. If the primary coil side is damaged, the primary coil and the outlet fixing plate / back plate can be replaced. In this way, maintenance and repair are extremely easy and economically effective technology.

[Brief description of drawings]

FIG. 1 is a side view of a transformer according to the present invention.

2 is a front view of the transformer of FIG. 1. FIG.

FIG. 3 is a rear view of the transformer of FIG.

4 is a cross-sectional view of the transformer of FIG. 1 taken along line IV-IV.

5 is a cross-sectional view taken along the line VV of FIG.

6 is a cross-sectional view taken along line VI-VI of FIG.

FIG. 7 is a plan view showing the structure of a primary coil.

FIG. 8 is a comparative explanatory diagram of the present invention and the prior art.

[Explanation of symbols]

1 ... Secondary coil; 2 ... Primary coil; 3 ... Insulating layer;
4,14 ... Copper stand; 5 ... Base; 6,7 ... Side plate; 8
…… Front plate; 9 …… Rear plate

Claims (1)

[Claims] 1. A copper plate that is bent into a closed-loop and single-cylinder shape with a gap left between the bent ends, or a single-layer copper pipe that has a gap formed along the entire circumference thereof. A pair of copper pedestals facing each other with the same distance as this gap are integrally attached to the ends, and holes are formed in each copper pedestal for passing the cooling medium in a direction parallel to the gap. The openings are the inlet and outlet of the cooling medium, the openings of the pair of holes on the opposite side are provided in the lower part of the copper stand, and the openings of the holes in the lower part have a small diameter so that the bending shape is the same as that of the cylindrical copper plate or copper pipe. The curved copper pipe is attached as a unit to make the cooling medium flow from one copper stand to the other copper stand. The copper stand has a cylindrical copper plate or a surface on which the copper pipe is attached. It is manufactured so that it is contacted and fixed on the smooth surface on the opposite side of the An inductor block having an insertion port for holding a metal stud is attached at one end of the opening of the part, and a coil of one turn is formed by the configuration of the cylindrical copper plate or the copper tube and the inductor block to form a secondary coil. A small-diameter copper tube is spirally wound as a coil and processed so that both ends are parallel and projected in the same direction, and a tape-shaped insulator is sandwiched between each winding. Insulation, and further wrap the entire primary coil with an insulating material such as a resin having excellent high frequency characteristics and excellent insulation, or impregnate the resin to reinforce the insulation and make it concentric with a certain interval. So that the primary coil is housed in the secondary coil via an insulating layer between the primary coil and the secondary coil, and the spiral copper tube serves as the primary coil and serves as a primary current path. cooling Path as When activated primary coil body, high-frequency induction heating transformer, wherein both the secondary coil circulating a cooling medium in the coil.