JP2020181828A - Manufacturing method of induction heating coil - Google Patents

Abstract

To provide a manufacturing method of an induction heating coil capable of manufacturing an induction heating coil so as to have a longer life, and an induction heating coil.SOLUTION: An induction heating coil 1 includes a coil portion 3 for induction heating of an object to be processed, a power supply portion 2 that supplies power to a coil portion 3, and a cooling water channel 5 arranged in the power supply portion 2 and the coil portion 3 and supplying cooling water to the coil portion 3. The coil portion 3, the power supply portion 2, and the cooling water channel 5 are formed by using a metal additive manufacturing method.SELECTED DRAWING: Figure 1

Description

The present invention relates to an induction heating coil and a method for manufacturing the induction heating coil.

For example, an induction heating coil may be used to heat-treat a metal mechanical part such as a shaft by high-frequency heating (see, for example, Patent Document 1). The induction heating coil described in Patent Document 1 has an annular coil portion capable of surrounding a shaft as an object to be processed. Then, a large current for generating induction heating is supplied to this coil portion. This large current is supplied to the coil portion, for example, via a metal member (power supply portion) brazed to the coil portion. Further, the coil portion is cooled because it becomes hot. For this cooling, cooling water passages are provided inside the power supply unit and inside the coil unit.

The cooling water passes through the inside of the power supply part and reaches the inside of the coil part to cool the coil part. The cooling water that has passed through the coil section is returned through the inside of the power supply section.

Japanese Unexamined Patent Publication No. 2013-136819

The coil portion is formed in a thin cylindrical shape as a whole, and the inside of the cylindrical portion is a cavity for cooling water. As described above, the coil portion has a complicated internal shape, and it is difficult to make it with a single part. Therefore, the coil portion is formed into a shape having a cavity by brazing a plurality of parts or the like. Then, this coil portion is brazed in a state of being abutted against a portion around the cooling water channel of the power supply portion. As a result, the coil portion is fixed to the power supply portion.

However, in order to perform the brazing work with high accuracy, skillful skill is required, and the brazing accuracy of the plurality of members constituting the coil part and the brazing accuracy of the coil part and the power supply part vary. Tends to grow. Therefore, the accuracy of brazing is greatly affected by the skill of the worker performing the brazing. As a result, it is difficult to make the brazing accuracy of each induction heating coil constant, and it is difficult to mass-produce the induction heating coil with uniform dimensions.

Moreover, when brazing between a plurality of members constituting the coil portion and brazing between the coil portion and the power supply portion, the temperature of the brazing is high, so that between the plurality of members constituting the coil portion. It is inevitable that thermal strain will occur and that thermal strain will occur between the coil section and the power supply section. Therefore, in order to suppress such thermal distortion, a special jig is required when brazing the coil portion and the power supply portion. The design of this jig also requires a high degree of intuition and experience to suppress thermal distortion of the coil section and power supply section.

Further, when brazing the coil part and the power supply part, it takes time to set the above jig and it takes time to prepare the jig, so that the production efficiency of the induction heating coil becomes low. .. Moreover, the degree of freedom in the brazing process and the machining process of the induction heating coil is low. Therefore, the degree of freedom in setting the shape of the induction heating coil in order to achieve the optimum heat treatment of the object to be processed is reduced. Further, since the brazed portion has a higher electrical resistivity than the other portions of the coil portion, it easily generates heat, has a large amount of expansion and contraction, and is easily fractured by fatigue. Therefore, the life of the brazed portion (occurrence of fracture) becomes the life of the induction heating coil. For this reason, further intuition and experience are required for the design of the brazed portion.

In view of the above circumstances, one of the objects of the present invention is to provide a method for manufacturing an induction heating coil and an induction heating coil capable of manufacturing the induction heating coil so as to have a longer life.

Further, one of another object of the present invention is to be able to manufacture the induction heating coil more easily and with higher accuracy, and further to increase the production efficiency of the induction heating coil.

(1) In order to solve the above problems, the induction heating coil according to a certain aspect of the present invention includes a coil portion for inductively heating the object to be processed and a power supply unit for supplying electric power to the coil portion. The coil section, the power supply section, and the refrigerant passage are arranged in the power supply section and the coil section, and include a refrigerant passage for supplying the refrigerant to the coil section. Is formed using.

According to this configuration, the refrigerant passages in the coil section and the power supply section are formed by using the metal additive manufacturing method. In the metal additive manufacturing method, an arbitrary three-dimensional shape can be formed by repeatedly performing the work of solidifying the molten metal after selectively applying heat to the powder metal layer to melt it. Therefore, even if the refrigerant passages formed in the coil section and the power supply section have a complicated shape, the coil section and the power supply section can be made of a single component. Therefore, it is not necessary to provide a brazed portion in either the coil portion itself or between the power supply portion and the coil portion. Therefore, the brazing work that requires skill is not required. Moreover, if the metal additive manufacturing method is used, it is possible to mass-produce induction heating coils of the same type with mechanical accuracy. Therefore, it is possible to mass-produce induction heating coils with uniform dimensions.

Moreover, since brazing is not required to form the coil portion itself and it is not necessary to braze the coil portion and the power supply portion, the thermal distortion of the coil portion itself due to the brazing work and the power supply portion No thermal strain occurs between the heating coil and the heating coil. Therefore, a dedicated jig for suppressing such thermal strain is unnecessary, and the induction heating coil can be manufactured more easily.

Further, since the work for setting the above-mentioned jig for brazing is not required, the production efficiency of the induction heating coil can be further increased. Moreover, the metal additive manufacturing method has a high degree of freedom in setting the shape. Therefore, it is possible to increase the degree of freedom in setting the shape of the induction heating coil in order to achieve the optimum heat treatment of the object to be processed. Further, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of thermal stress in the coil portion and in the connection portion between the power supply portion and the coil portion. Therefore, the life of the induction heating coil can be extended.

Therefore, according to the present invention, the induction heating coil can be manufactured so as to have a longer life. Further, the induction heating coil can be manufactured more easily and with higher accuracy, and the production efficiency of the induction heating coil can be further increased.

(2) Preferably, when the induction heating coil is formed by the metal additive manufacturing method, a support portion for supporting a predetermined portion of the induction heating coil is formed, and the induction heating coil is formed with the support. It has a posterior part after excision of the part.

According to this configuration, in the support portion, for example, the coil portion as a protruding portion as a predetermined portion protruding from the power supply portion sinks under its own weight with respect to the metal powder layer during modeling by the metal additive manufacturing method. It can be used to suppress the occurrence of misalignment. Thereby, the dimensional accuracy of the induction heating coil can be further improved. The induction heating coil formed by using such a support portion has a rear portion after excision.

(3) More preferably, the coil portion has a thickness smaller than the thickness of the power supply portion and is formed in a shape protruding from the power supply portion, and the support portion is formed by the metal additive manufacturing method. When the induction heating coil is formed, it is formed so as to support the coil portion as the predetermined portion.

According to this configuration, an induction heating coil having a thin coil portion can be formed more accurately.

(4) Preferably, the refrigerant passage includes a power supply section side passage formed in the power supply section and a coil section side passage formed in the coil section, and the power supply section side passage and the coil. The cross-sectional area of the connecting portion with the portion-side passage continuously changes as it advances in the traveling direction of the refrigerant.

Usually, the shape of the connection portion between the power supply portion and the coil portion changes greatly, and the thermal stress tends to increase locally. Around such a connection portion, the shape of the refrigerant passage is a shape that continuously changes. As a result, the bias of the thermal stress at the connection portion can be suppressed. Therefore, the life of the induction heating coil can be extended.

(5) Preferably, the refrigerant passage includes a coil portion side passage formed in the coil portion, the coil portion side passage has an undulating portion, and the undulating portion is in the circumferential direction of the coil portion. As it advances along the coil portion, it extends so as to undulate in the thickness direction of the coil portion.

According to this configuration, a larger contact area between the coil portion and the refrigerant can be secured. Therefore, since the heat generated in the coil portion can be more efficiently absorbed by the refrigerant, it is possible to more reliably suppress the bias of the thermal stress due to the overheating of the coil portion. The ease of manufacturing an induction heating coil having a refrigerant passage having such a three-dimensionally complicated shape becomes remarkable by using the additive manufacturing method.

(6) Preferably, the second refrigerant passage further includes a second refrigerant passage through which the refrigerant for the object to be processed for cooling the object to be processed, which is induced and heated by the coil portion, passes, and an injection nozzle. And the injection nozzle is formed by using the metal laminated molding method, the injection nozzle is connected to the second refrigerant passage, and the injection nozzle has the coil portion to be subjected to the heat treatment of the object to be processed. It is open toward the portion facing the processed object, and the refrigerant for the object to be processed can be injected onto the object to be processed.

According to this configuration, the object to be processed heated by the induction heating by the coil portion can be cooled by the refrigerant for the object to be processed. As described above, the ease of manufacturing the induction heating coil having the second refrigerant passage in addition to the refrigerant passage becomes remarkable by using the additive manufacturing method.

(7) In order to solve the above problems, the method for manufacturing an induction heating coil according to a certain aspect of the present invention includes a coil portion for inductively heating an object to be processed and an electric power for supplying electric power to the coil portion. It includes a metal lamination molding step of forming a supply section, a refrigerant passage arranged in the power supply section and the coil section, and for supplying a refrigerant to the coil section by using a metal lamination molding method.

According to this configuration, the refrigerant passages in the coil section and the power supply section are formed by using the metal additive manufacturing method. In the metal additive manufacturing method, an arbitrary three-dimensional shape can be formed by repeatedly performing the work of solidifying the molten metal after selectively applying heat to the powder metal layer to melt it. Therefore, even if the refrigerant passages formed in the coil section and the power supply section have a complicated shape, the coil section and the power supply section can be made of a single component. Therefore, it is not necessary to provide a brazed portion in either the coil portion itself or between the power supply portion and the coil portion. Therefore, the brazing work that requires skill is not required. Moreover, if the metal additive manufacturing method is used, it is possible to mass-produce induction heating coils of the same type with mechanical accuracy. Therefore, it is possible to mass-produce induction heating coils with uniform dimensions.

Moreover, since brazing is not required to form the coil portion itself and it is not necessary to braze the coil portion and the power supply portion, the thermal distortion of the coil portion itself due to the brazing work and the power supply portion No thermal strain occurs between the heating coil and the heating coil. Therefore, a dedicated jig for suppressing such thermal strain is unnecessary, and the induction heating coil can be manufactured more easily.

Further, since the work for setting the above-mentioned jig for brazing is not required, the production efficiency of the induction heating coil can be further increased. Moreover, the metal additive manufacturing method has a high degree of freedom in setting the shape. Therefore, it is possible to increase the degree of freedom in setting the shape of the induction heating coil in order to achieve the optimum heat treatment of the object to be processed. Further, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of thermal stress in the coil portion and in the connection portion between the power supply portion and the coil portion. Therefore, the life of the induction heating coil can be extended.

Therefore, according to the present invention, the induction heating coil can be manufactured so as to have a longer life. Further, the induction heating coil can be manufactured more easily and with higher accuracy, and the production efficiency of the induction heating coil can be further increased.

(8) Preferably, the metal lamination molding step further includes a cutting step of forming a support portion that supports a predetermined portion of the induction heating coil and cutting the support portion.

According to this configuration, in the support portion, for example, the coil portion as a protruding portion as a predetermined portion protruding from the power supply portion sinks under its own weight with respect to the metal powder layer during modeling by the metal additive manufacturing method. It can be used to suppress the occurrence of misalignment. Thereby, the dimensional accuracy of the induction heating coil can be further improved.

(9) In order to solve the above problems, the induction heating coil according to a certain aspect of the present invention includes a coil portion for inductively heating the object to be processed and a power supply unit for supplying electric power to the coil portion. The coil unit, the power supply unit, and the refrigerant passage are provided with a refrigerant passage which is arranged in the power supply unit and the coil unit and for supplying a refrigerant to the coil unit, and the coil unit, the power supply unit, and the refrigerant passage are a single member. Is integrally formed using.

According to this configuration, it is not necessary to provide a brazed portion in either the coil portion itself or between the power supply portion and the coil portion. Therefore, thermal distortion between the power supply unit and the heating coil unit due to the brazing operation does not occur. Therefore, a dedicated jig for suppressing such thermal strain is unnecessary, and the induction heating coil can be manufactured more easily. Further, since the work for setting the above-mentioned jig for brazing is not required, the production efficiency of the induction heating coil can be further increased. Further, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of thermal stress in the coil portion and in the connection portion between the power supply portion and the coil portion. Therefore, the life of the induction heating coil can be extended.

Therefore, according to the present invention, the induction heating coil can be manufactured so as to have a longer life.

(10) In order to solve the above problems, the induction heating coil according to a certain aspect of the present invention includes a coil portion for inductively heating the object to be processed and a power supply unit for supplying power to the coil portion. The coil portion is provided with a refrigerant passage provided in the power supply unit and the coil portion to form a gap for supplying the refrigerant to the coil portion, and the coil portion is integrally made of the same metal material having conductivity. It is formed and does not have a brazed structure for all the parts of the coil portion, and the variation of the electric resistance rate per unit volume (mm ³ ) of the metal material is 5% or less.

According to this configuration, the coil portion is not provided with a brazed portion. Therefore, thermal distortion of the coil portion due to the brazing work does not occur. Therefore, since the brazed portion, which is a discontinuous portion in terms of electrical resistance, is not required, the bias of the thermal stress in the coil portion can be reduced. Therefore, the life of the induction heating coil can be extended. Further, the coil portion is integrally formed of the same conductive metal material. Therefore, the variation in the electrical resistivity in all the parts in the coil part per unit volume is small as compared with the conventional coil part formed by brazing a plurality of metal materials. Further, the variation in the electrical resistivity (Ω · m) per unit volume (1 mm ³ ) is 5% or less in all the parts in the coil portion. Therefore, in the expansion and contraction due to the heat of the coil portion, the variation in the expansion and contraction amount in the coil portion is unlikely to occur. Therefore, fatigue fracture in the coil portion can be suppressed, and the life of the induction heating coil can be further extended by extending the life of the coil portion.

Therefore, according to the present invention, the induction heating coil can be manufactured so as to have a longer life.

(11) More preferably, the coil portion and the power supply portion are integrally formed of the same metal material, and the coil portion and all the parts of the power supply portion are brazed. However, the variation in electrical resistivity per unit volume (mm ³ ) of the metal material is 5% or less.

According to this configuration, the coil portion and the power supply portion are not provided with brazed portions. Therefore, no brazing portion is provided at the connection portion between the coil portion and the power supply portion. Therefore, thermal distortion of the coil portion and the power supply portion due to the brazing operation does not occur. Therefore, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of thermal stress in the coil portion and the power supply portion. Therefore, the life of the induction heating coil can be extended. Further, the coil portion and the power supply portion are integrally formed of the same conductive metal material. For this reason, the electrical resistivity varies in all parts in the coil part and the power supply part per unit volume as compared with the conventional coil part and the power supply part formed by brazing a plurality of metal materials. small. Further, the variation in the electrical resistivity (Ω · m) per unit volume (1 mm ³ ) is 5% or less in all the parts in the coil part and the power supply part. Therefore, in the expansion and contraction due to heat of the coil unit and the power supply unit, it is difficult for a difference in the amount of expansion and contraction in the coil unit and the power supply unit to occur. Therefore, fatigue failure in the coil section and the power supply section can be suppressed, and the life of the induction heating coil can be further extended by extending the life of the coil section and the power supply section.

According to the present invention, the induction heating coil can be manufactured so as to have a longer life. Further, the induction heating coil can be manufactured more easily and with higher accuracy, and the production efficiency of the induction heating coil can be further increased.

It is a perspective view of the induction heating coil which concerns on 1st Embodiment of this invention. It is a side view of an induction heating coil. It is a top view of the induction heating coil. It is sectional drawing in the state which the periphery of the coil part of an induction heating coil is viewed in a plan view. It is sectional drawing in the state which the periphery of the coil part was viewed sideways. It is an enlarged perspective view of the periphery of the coil part of an induction heating coil. It is a schematic diagram of the manufacturing system for manufacturing an induction heating coil. It is a flowchart for demonstrating an example of the manufacturing process of an induction heating coil. It is a flowchart for demonstrating an example of a laminated molding process. Each of (a) to (c) is a schematic side view of a main part for explaining a laminated molding process, and a part thereof is shown in cross section. (A) is a graph schematically showing the electrical resistivity of each part of the induction heating coil according to the first embodiment, and (b) schematically shows the electrical resistivity of each part of the induction heating coil according to the comparative example. It is a graph. It is a top view of the main part for demonstrating the modification of the 1st Embodiment. It is a perspective view of the induction heating coil which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the coil part of FIG. 13 enlarged. It is a side view of a coil part. It is a top view of the coil part. It is a top view of the main part for demonstrating a further modification. It is a figure for demonstrating the main part of the manufacturing process (horizontal type) of a power supply part and a coil part which concerns on a further modification, (a) shows the state before the support part is excised, and (a) b) shows the state after the support portion has been excised. It is a figure for demonstrating the main part of the manufacturing process (vertical installation type) of a power supply part and a coil part which concerns on a further modification, (a) shows the state before the support part is excised, and (a) b) shows the state after the support portion has been excised.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a perspective view of the induction heating coil 1 according to the first embodiment of the present invention. FIG. 2 is a side view of the induction heating coil 1. FIG. 3 is a plan view of the induction heating coil 1. FIG. 4 is a cross-sectional view of the induction heating coil 1 in a plan view of the periphery of the coil portion 3. FIG. 5 is a cross-sectional view of the coil portion 3 with a side view. FIG. 6 is an enlarged perspective view of the periphery of the coil portion 3 of the induction heating coil 1.

In the following, the top and bottom, front and back, and left and right when the induction heating coil 1 is viewed in a state of facing the front surface of the induction heating coil 1 are referred to as up and down, front and back, and left and right, respectively.

With reference to FIGS. 1 to 3, the induction heating coil 1 is used for performing a heat treatment such as quenching treatment on an object 100 to be processed, which is a metal shaft such as a shaft. Examples of the object 100 to be processed include an intermediate shaft of a steering shaft of an automobile and a gear. The induction heating coil 1 induces and heats the object to be processed 100 by electric power given from a commercial power source or the like, and heat-treats the object to be processed 100.

The current value of the electric power given to the induction heating coil 1 is, for example, several thousand amperes, which is extremely large. For this reason, if the induction heating coil 1 has a discontinuous portion of the electrical resistivity, fatigue fracture due to expansion / contraction due to heat tends to occur at that portion. Therefore, in the present embodiment, the induction heating coil 1 that is less likely to cause such fatigue fracture is adopted.

The induction heating coil 1 is formed by using a material having excellent conductivity and thermal conductivity. Examples of such a material include pure copper and oxygen-free copper. In this embodiment, the induction heating coil 1 is formed by using a metal additive manufacturing method. That is, the induction heating coil 1 does not have a configuration in which a plurality of metal members separately formed in advance are integrally combined by brazing or the like. The method for manufacturing the induction heating coil 1 will be described in detail later.

The induction heating coil 1 is formed in an elongated shape in the front-rear direction as a whole, is formed in a substantially L-shape in a side view, and is formed in a substantially T-shape in a plan view. Further, the induction heating coil 1 is formed in a symmetrical shape.

The induction heating coil 1 has a power supply unit 2, a coil unit 3, an insulator 4, and a cooling water channel 5. In the present embodiment, the power supply unit 2, the coil unit 3, and the cooling water channel 5 are integrally formed by using a single member.

The power supply unit 2 is provided to supply electric power from a power source (not shown) to the coil unit 3 and to circulate cooling water for cooling the coil unit 3 to the coil unit 3.

The power supply unit 2 has a first division body 6R and a second division body 6L.

The first divided body 6R and the second divided body 6L are formed in a symmetrical shape. The divided bodies 6R and 6L each have a rear wall 7, a main body 8, and a rib 9.

The rear walls 7 and 7 are portions formed in a flat plate shape and face in the front-rear direction. Ports 10 and 10 are provided on the rear walls 7 and 7. The ports 10 and 10 are formed in a cylindrical shape. One of the ports 10 and 10 is provided as a cooling water inlet, and the other is provided as a cooling water outlet. Main bodies 8 and 8 extend forward from the rear walls 7 and 7.

The main bodies 8 and 8 are portions formed in a substantially L shape in a side view, and are elongated in the front-rear direction. The main bodies 8 and 8 are adjacent to each other on the left and right sides of the insulator 4. The main bodies 8 and 8 have vertical wall portions 11 and 11 and lower wall portions 12 and 12.

The vertical wall portions 11 and 11 are each formed in a square columnar shape. The vertical wall portions 11 and 11 are continuous with the front surfaces of the corresponding rear walls 7 and 7 and are located on the lower end side of the corresponding rear walls 7 and 7. Corresponding lower wall portions 12 and 12 extend forward from the vertical wall portions 11 and 11, respectively.

The lower wall portions 12 and 12 are each formed in the shape of a flat plate, and are formed in the shape of an elongated rectangular plate in the front-rear direction. The thickness direction of the lower wall portions 12 and 12 is the vertical direction. Corresponding ribs 9 and 9 extend upward from the lower wall portions 12 and 12.

The ribs 9 and 9 are plate-shaped portions formed to reinforce the main bodies 8 and 8 and are connected to both the corresponding vertical wall portions 11 and 11 and the lower wall portions 12 and 12. The thickness direction of the ribs 9 and 9 is the left-right direction. An insulator 4 is sandwiched between the ribs 9 and 9.

The insulator 4 is provided as a portion for preventing the main bodies 8 and 8 from coming into direct contact with each other. The insulator 4 is a sheet-like portion arranged between the main bodies 8 and 8 and is fixed to the main bodies 8 and 8. The current from one of the divided bodies 6R and 6L flows to the other of the divided bodies 6R and 6L via the coil portion 3.

The coil portion 3 is provided as a portion that causes induction heating of the object to be processed 100 in a state of surrounding the object to be processed 100. The coil portion 3 is formed in a substantially cylindrical shape as a whole. The coil portion 3 is continuous with the tip portions of the lower wall portions 12 and 12 of the main bodies 8 and 8. The coil portion 3 has a thickness smaller than the thickness of the power supply portion 2 (length in the vertical direction), and is formed in a shape protruding forward from the power supply portion 2.

In the present embodiment, the entire induction heating coil 1 except for the insulator 4 is formed by additive manufacturing. As a result, the connection portion 13 between the coil portion 3 and the power supply portion 2 has a shape in which the degree of concentration of thermal stress is reduced. That is, in the present embodiment, the coil portion 3, the power supply portion 2, and the cooling water channel 5 of the induction heating coil 1 are formed by using the metal additive manufacturing method. In the metal additive manufacturing method, for example, a metal product having a desired shape is sintered and created by repeating the work of laying the metal powder in layers and the work of selectively melting the metal powder at each position of the layered metal powder. Say the method.

The coil portion 3 is formed in an endless ring shape, and has one end portion 3a and the other end portion 3b. The one end portion 3a is continuous with the tip of the lower wall portion 12 of the first partition body 6R. The other end portion 3b is continuous with the tip of the lower wall portion 12 of the second divided body 6L.

The outer peripheral surface 3c of the coil portion 3 is formed in an ended cylindrical shape. The inner peripheral surface 3d of the coil portion 3 has a cylindrical surface 3e parallel to the outer peripheral surface 3c and a tapered surface 3f extending from the cylindrical surface 3e toward the upper end surface 3g of the coil portion 3. The cylindrical surface 3e is formed in an endless cylindrical shape, and is arranged coaxially with the outer peripheral surface 3c. The lower end of the cylindrical surface 3e is continuous with the lower end surface 3h of the coil portion 3.

The tapered surface 3f is formed in a conical taper shape in which the diameter increases from the cylindrical surface 3e to the upper end surface 3g of the coil portion 3. The upper end surface 3g and the lower end surface 3h of the coil portion 3 are each formed on a flat surface and extend in parallel with each other. Further, the upper end surface 3g and the lower end surface 3h each extend in a direction orthogonal to the central axis S1 of the coil portion 3.

In the present embodiment, the upper end surface 3g of the coil portion 3 and the upper end surfaces 12a, 12a of the lower wall portions 12, 12 are arranged on the same plane (on a plane). Further, the lower end surface 3h of the coil portion 3 and the lower end surfaces 12b, 12b of the lower wall portions 12, 12 are arranged on the same plane (on a plane). Further, the tip portions of the lower wall portions 12 and 12 are formed in an arc shape corresponding to the cylindrical shape of the outer peripheral surface 3c of the coil portion 3 in a plan view.

In the present embodiment, the connecting portions 13 and 13 between the tip portions of the lower wall portions 12 and 12 and the coil portion 3 have a discontinuous stepped shape instead of a smooth continuous curved shape. However, in the present embodiment, the induction heating coil 1 is formed by the metal additive manufacturing method, and the bias of thermal strain due to thermal stress at high temperature is reduced. Therefore, the decrease in strength due to thermal stress at the connecting portions 13 and 13 between the lower wall portions 12 and 12 of the divided bodies 6R and 6L and the coil portion 3 is sufficiently suppressed.

A rear portion 14 after excision is formed on the upper end surface 3g of the coil portion 3. The post-cut portion 14 is a portion to which a support portion 50 (described later) that supports the coil portion 3 as a predetermined portion is connected when the induction heating coil 1 is formed by the metal additive manufacturing method. The post-excision portion 14 is a trace portion after excision of the support portion 50. The post-cut portion 14 is formed on, for example, the entire surface of the upper end surface 3 g of the coil portion 3. A cooling water channel 5 is formed in the power supply unit 2 and the coil unit 3 having the above configuration.

The cooling water channel 5 is an example of the "refrigerant passage" of the present invention. The cooling water channel 5 is provided as a portion through which cooling water as a refrigerant for cooling the coil portion 3 passes. In the present embodiment, the cooling water enters the induction heating coil 1 from the power supply unit 2, passes through the coil unit 3, and then returns to the power supply unit 2, and is returned from the power supply unit 2 to the outside of the induction heating coil 1. Is discharged to. The cooling water channel 5 is arranged in the power supply unit 2 and the coil unit 3.

The cooling water channel 5 has a power supply section side water channel 15 and a coil section side water channel 16.

The power supply unit side water channel 15 is a water channel formed in the power supply unit 2, and supplies cooling water to the coil unit side water channel 16 and discharges cooling water from the coil unit side water channel 16. The power supply unit side water channel 15 is an example of the “power supply unit side water channel” of the present invention.

The power supply unit side water channel 15 has a first water channel 21R formed in the first divided body 6R and a second water channel 21L formed in the second divided body 6L.

The first water channel 21R is provided as a cooling water supply channel to the coil portion side water channel 16. The first water channel 21R is open to a port 10 provided in the first division body 6R, and is formed in an L shape in the rear wall 7 of the first division body 6R in a front view. In order to form a portion 21aR of the first water channel 21R extending to the left and right in the rear wall 7 of the first partition body 6R by machining, it is usually opened to the right end surface of the rear wall 7 continuously with the portion 21aR. It is necessary to form a hole for processing. Then, it is necessary to provide a metal plug for closing the processing hole. However, in the present embodiment, since the induction heating coil 1 is formed by the additive manufacturing method, such a metal plug is unnecessary.

The first water channel 21R extends from the rear wall 7 to the vertical wall portion 11 of the main body 8 and extends from the vertical wall portion 11 to the lower wall portion 12 in the first divided body 6R. The first water channel 21R extends linearly along the front-rear direction in the lower wall portion 12. The first water channel 21R has a rectangular cross-sectional shape (shape in front view) orthogonal to the front-rear direction in the lower wall portion 12. The tip of the first water channel 21R is formed in a rectangular shape in front view at the tip of the lower wall portion 12, and is smoothly continuous with the coil portion side water channel 16. The first water channel 21R is formed in a symmetrical shape with the second water channel 21L.

The second water channel 21L is provided as a discharge channel for cooling water from the coil portion side water channel 16. The second water channel 21L is open to a port 10 provided in the second divided body 6L, and is formed in an L shape in the rear wall 7 of the second divided body 6L in a front view. In order to form a portion 21aL extending to the left and right in the rear wall 7 of the second divided body 6L of the second water channel 21L by machining, it is usually opened to the left end surface of the rear wall 7 continuously with the portion 21aL. It is necessary to form a hole for processing. Then, it is necessary to provide a metal plug for closing the processing hole. However, in the present embodiment, since the induction heating coil 1 is formed by the additive manufacturing method, such a metal plug is unnecessary.

The second water channel 21L extends from the rear wall 7 of the second divided body 6L to the vertical wall portion 11 of the main body 8L, and extends from the vertical wall portion 11 to the lower wall portion 12. The second water channel 21L extends linearly along the front-rear direction in the lower wall portion 12. The second water channel 21L has a rectangular cross-sectional shape (shape in front view) orthogonal to the front-rear direction in the lower wall portion 12. The tip of the second water channel 21L is formed in a rectangular shape in front view at the tip of the lower wall portion 12, and is smoothly continuous with the coil portion side water channel 16. The coil portion side water channel 16 is connected to the first water channel 21R and the second water channel 21L having the above configuration.

With reference to FIGS. 4 to 6, the coil portion side water channel 16 is provided to cool the periphery of the coil portion 3, particularly the inner peripheral surface 3d of the coil portion 3 which becomes hot. The coil portion side water channel 16 is an endless annular water channel formed as a whole, and is formed around the central axis S1 of the coil portion 3. The coil portion side water channel 16 is formed over most of the coil portion 3 in the circumferential direction C1 of the coil portion 3.

The coil portion side water channel 16 has an inlet 31, an outer peripheral side surface 32, an inner peripheral side surface 33, an upper surface 34, a lower surface 35, an outlet 36, a first expansion portion 37, and a second expansion portion 38. doing.

The inlet 31 is provided as a portion smoothly connected to the tip end portion of the first water channel 21R. The shape of the inlet 31 is the same as the shape of the tip of the first water channel 21R, and in the present embodiment, the inlet 31 is formed in a rectangular shape in a front view and extends along the circumferential direction C1. No step is formed between the inlet 31 and the tip of the first water channel 21R, and the bias of strain due to thermal stress is suppressed at the connection portion between the inlet 31 and the first water channel 21R. ..

The outlet 36 is provided as a portion that is smoothly connected to the tip end portion of the second water channel 21L. The shape of the outlet 36 is the same as the shape of the tip end portion of the second water channel 21L, and in the present embodiment, it is formed in a rectangular shape in front view and extends along the circumferential direction C1. No step is formed between the outlet 36 and the tip of the second water channel 21L, and the bias of strain due to thermal stress is suppressed at the connection portion between the outlet 36 and the second water channel 21L. ..

An outer peripheral side surface 32, an inner peripheral side surface 33, an upper surface 34, and a lower surface 35 extend between the inlet 31 and the outlet 36.

Regarding the outer peripheral side surface 32, the intermediate portion 32c as a portion other than both end portions 32a and 32b of the outer side surface 32 in the circumferential direction C1 of the coil portion 3 is formed in a shape corresponding to a part of the cylindrical surface and is flat. In view, it is formed in a substantially arc shape.

One end portion 32a of the outer peripheral side surface 32 is a connecting portion with the inlet 31, and this portion constitutes a smooth curved surface that curves toward the inlet 31 side. The center of curvature of the intermediate portion 32c of the outer peripheral side surface 32 is the central axis S1 of the coil portion 3, but the center of curvature A1 of one end portion 32a of the outer peripheral side surface 32 is the connection portion 13 between the power supply portion 2 and the coil portion 3. It is located outside the induction heating coil 1 in the vicinity. In this way, by forming the outer peripheral side surface 32 so that the center of curvature (the direction in which the convex portion of the coil portion 3 faces in the plan view) between the intermediate portion 32c and the one end portion 3a of the outer peripheral side surface 32 is different from the inlet 31. The shape around the connection portion with the outer peripheral side surface 32 can be smoothed. As a result, stress concentration due to thermal stress is suppressed around the connection portion between the first water channel 21R and the coil portion side water channel 16. The other end 32b of the outer peripheral side surface 32 is formed in a shape symmetrical with the one end 32a of the outer peripheral side surface 32.

The other end 32b of the outer peripheral side surface 32 is a connecting portion with the outlet 36, and the portion constitutes a smooth curved surface that curves toward the outlet 36 side. The center of curvature A2 of the other end 32b of the outer peripheral side surface 32 is located outside the induction heating coil 1 in the vicinity of the connection portion 13 between the power supply portion 2 and the coil portion 3. In this way, the outlet 36 is formed by forming the outer peripheral side surface 32 so that the center of curvature (the direction in which the convex portion of the coil portion 3 faces in the plan view) is different between the intermediate portion 32c and the other end portion 3b of the outer peripheral side surface 32. The shape around the connection portion between the outer peripheral side surface 32 and the outer peripheral side surface 32 can be smoothed. As a result, stress concentration due to thermal stress is suppressed around the connection portion between the second water channel 21L and the coil portion side water channel 16. The inner peripheral side surface 33 is arranged so as to be surrounded by the outer peripheral side surface 32.

The inner peripheral side surface 33 extends from the inlet 31 toward the central axis S1 of the coil portion 3, then extends along the circumferential direction C1, and further extends toward the exit 36. The inner peripheral side surface 33 has one end 33a, the other end 33b, and an intermediate 33c.

One end 33a of the inner peripheral side surface 33 is provided as a portion extending from the inlet 31 toward the inner peripheral surface 3d side of the coil portion 3. In a plan view, one end 33a of the inner peripheral side surface 33 has a shape extending so as to be separated from one end 32a of the outer peripheral side surface 32 as the distance from the inlet 31 increases, and is convex toward one end 3a of the coil portion 3. It is formed in a curved shape. One end 33a of the inner peripheral side surface 33 is formed as a smoothly continuous surface as a whole, and is smoothly connected to the intermediate portion 33c of the inner peripheral side surface 33. In a plan view, the boundary portion 33d between the one end portion 33a of the inner peripheral side surface 33 and the intermediate portion 33c is located near the virtual line L1 connecting the central axis S1 of the coil portion 3 and the one end portion 32a of the outer peripheral side surface 32. There is. The boundary portion 33d is arranged at a position overlapping the tapered surface 3f of the inner peripheral surface 3d of the coil portion 3 in a plan view. The other end 33b of the inner peripheral side surface 33 is arranged symmetrically with the one end 33a of the inner peripheral side surface 33.

The other end 33b of the inner peripheral side surface 33 is provided as a portion extending from the outlet 36 toward the inner peripheral surface 3d side of the coil portion 3. In a plan view, the other end 33b of the inner peripheral side surface 33 has a shape extending so as to be separated from the other end 32b of the outer peripheral side surface 32 as the distance from the outlet 36 increases, and the other end 3b of the coil portion 3 has a shape. It is formed in a curved shape that is convex toward it. The other end 33b of the inner peripheral side surface 33 is formed as a surface that is smoothly continuous as a whole, and is smoothly connected to the intermediate portion 33c of the inner peripheral side surface 33. In a plan view, the boundary portion 33e between the other end portion 33b of the inner peripheral side surface 33 and the intermediate portion 33c is located near the virtual line L2 connecting the central axis S1 of the coil portion 3 and the other end portion 32b of the outer peripheral side surface 32. doing. The boundary portion 33e is arranged at a position overlapping the tapered surface 3f of the inner peripheral surface 3d of the coil portion 3 in a plan view.

The intermediate portion 33c of the inner peripheral side surface 33 is formed concentrically with the intermediate portion 32c of the outer peripheral side surface 32, and is formed in an arc shape in a plan view. The lower end of the inner peripheral side surface 33 and the lower end of the outer peripheral side surface 32 are connected by a lower surface 35. The lower surface 35 of the coil portion side water channel 16 extends parallel to the lower end surface 3h of the coil portion 3. Further, the upper end portion of the inner peripheral side surface 33 and the upper end portion of the outer peripheral side surface 32 are connected by the upper surface 34.

The upper surface 34 of the coil portion side water channel 16 is formed concentrically with the lower surface 35, and is formed in an endd ring in a plan view. The upper surface 34 has a flat surface 34a and an inclined surface 34b.

The flat surface 34a extends parallel to the upper end surface 3g of the coil portion 3. The flat surface 34a is continuous with the entire upper end portion of the outer peripheral side surface 32, and is continuous with both end portions 33a and 33b of the inner peripheral side surface 33. The inclined surface 34b of the coil portion side water channel 16 is formed in an inclined shape extending from the inner peripheral portion of the flat surface 34a of the coil portion side water channel 16 toward the inner peripheral side surface 33. The inner peripheral side surface 33 is formed in a tapered shape extending downward from the flat surface 34a toward the inner peripheral side surface 33 side. One end of the inclined surface 34b in the circumferential direction C1 is continuous with one end 33a of the inner peripheral side surface 33. The other end of the inclined surface 34b in the circumferential direction C1 is continuous with the other end 33b of the inner peripheral side surface 33.

With the above configuration, the first expansion portion 37 is formed in the vicinity of the inlet 31 of the coil portion side water channel 16, and the second expansion portion 38 is formed in the vicinity of the outlet 36 of the coil portion side water channel 16. ing.

In the cross section orthogonal to the traveling direction F1 of the cooling water, the cross-sectional area at the first expansion portion 37 is larger than the cross-sectional area at the inlet 31. Then, when proceeding from the first expansion portion 37 to the downstream side in the traveling direction F1, the cross-sectional area of the coil portion side water channel 16 in the intermediate portion 32c of the outer peripheral side surface 32 becomes smaller than the cross-sectional area in the first expansion portion 37. There is. That is, the coil portion side water channel 16 has a complicated shape such that the cross-sectional area in a cross section orthogonal to the traveling direction F1 is once expanded around the inlet 31 and then the cross-sectional area is reduced.

In the same manner as described above, in the cross section orthogonal to the traveling direction F1 of the cooling water, the cross-sectional area of the coil portion side water channel 16 in the intermediate portion 32c of the outer peripheral side surface 32 becomes smaller than the cross-sectional area in the second expansion portion 38. There is. Then, in the second expansion portion 38, the cross-sectional area orthogonal to the traveling direction F1 is larger than the cross-sectional area at the exit 36. That is, when the coil portion side water channel 16 advances from the intermediate portion 32c of the outer peripheral side surface 32 to the second expansion portion 38, the cross-sectional area in the cross section orthogonal to the traveling direction F1 once expands, and then the cross-sectional area reaches the outlet 36. It has a complicated shape that shrinks.

With the above configuration, the cross-sectional area of the connecting portion 13 between the power supply portion side water channel 15 and the coil portion side water channel 16 continuously changes as the cooling water advances in the traveling direction F1. The above is the schematic configuration of the induction heating coil 1. Next, the manufacturing system of the induction heating coil 1 and the manufacturing method of the induction heating coil 1 will be described.

[Manufacturing system for induction heating coil]
FIG. 7 is a schematic view of a manufacturing system 40 for manufacturing the induction heating coil 1. As shown in FIG. 7, the manufacturing system 40 includes a CAD (Computer Aided Design) device 41, a data conversion device 42, and a manufacturing device 43.

The CAD device 41 is, for example, a 3D-CAD device capable of displaying an image three-dimensionally on a screen. In this embodiment, the CAD device 41 includes a computer and software installed on the computer. The designer of the induction heating coil 1 creates CAD data (image data) for creating the induction heating coil 1 by operating the CAD device 41. The CAD data created by the CAD device 41 is output to the data conversion device 42.

The data conversion device 42 is provided as a device for converting CAD data into data for operating the manufacturing device 43. The present embodiment includes a data conversion device 42, a computer, and software installed on the computer.

The data conversion device 42, for example, has a plurality of layer images (two-dimensional) obtained by slicing a three-dimensional image of the induction heating coil 1 specified by CAD data at predetermined intervals along the vertical direction of the coil unit 3. It is divided into images) and the data of the plurality of layer images is retained. The predetermined interval corresponds to the thickness of one layer of metal powder to be laminated in the manufacturing apparatus 43, and is, for example, about several tens of μm. The data of the plurality of layer images is given to the manufacturing apparatus 43.

The manufacturing apparatus 43 is an apparatus for melting and sintering metal powder. In this embodiment, the induction heating coil 1 is formed by a manufacturing apparatus 43, for example, a selective laser melting method. In the present embodiment, the manufacturing apparatus 43 includes a laser light source 44, a control unit 45, a movable base 46, and a powder supply unit 47.

The laser light source 44 is provided to give heat energy to the metal powder. The laser beam from the laser light source 44 may be irradiated to a desired position of the metal powder by dislocating the laser light source 44 itself by using a driving device (not shown), or the laser light source 44 is in a fixed state. Then, a galvanometer mirror may be used to irradiate the desired position. The laser light source 44 is controlled by the control unit 45.

The control unit 45 includes a CPU, RAM, ROM, and the like, and is given data from the data conversion device 42 and the like. The control unit 45 controls the laser light source 44, the movable base 46, and the powder supply unit 47. More specifically, the control unit 45 determines the irradiation amount of the laser beam to a predetermined portion of the metal powder based on the image data given from the data conversion device 42, and based on the determined irradiation amount, the metal powder. Irradiate a laser beam to a predetermined location. The irradiation amount of the laser beam may be set by the data conversion device 42.

The metal powder irradiated with the laser beam is placed on the movable table 46. The movable base 46 is provided to hold the metal powder. The movable base 46 has, for example, a substantially horizontal upper surface, on which the metal powder is placed. Further, the movable base 46 has a drive mechanism (not shown) and can be displaced in the vertical direction. Metal powder is supplied to the movable table 46 from the powder supply unit 47.

The powder supply unit 47 has a storage unit for accommodating the metal powder and a supply unit for supplying the metal powder to the movable table 46. The powder supply unit 47 forms a metal powder layer having a thickness (several tens of μm in the present embodiment) corresponding to the predetermined interval described above on the movable table 46.

[Manufacturing process of induction heating coil]
Next, the process of manufacturing the induction heating coil 1 will be described with reference to FIG. 8 and the like. FIG. 8 is a flowchart for explaining an example of the manufacturing process of the induction heating coil 1. In the following, when the explanation is made using the flowchart, the drawings other than the flowchart will be referred to as appropriate.

When manufacturing the induction heating coil 1 with reference to FIG. 8, the designer first creates CAD data for the induction heating coil 1 using the CAD device 41 (step S1).

Next, the designer sets the stacking direction of the metal powder at the time of stacking modeling of the induction heating coil 1 in the manufacturing apparatus 43 (step S2). In the present embodiment, for example, the stacking direction is set so that the induction heating coil 1 is completed facing downward. Next, the manufacturing apparatus 43 creates the induction heating coil 1 by the metal additive manufacturing method using the CAD data (step S3). This step S3 is an example of the "laminated modeling step" of the present invention. As a result, the induction heating coil 1 is completed. Next, in the post-treatment step, the support portion 50 formed on the induction heating coil 1 is removed (step S4).

Next, the laminated modeling step (step S3) using the manufacturing apparatus 43 will be described more specifically. FIG. 9 is a flowchart for explaining an example of the laminated molding process. With reference to FIG. 9, in the laminated molding step, first, the data conversion device 42 displays a plurality of three-dimensional images of the induction heating coil 1 specified by the CAD data created by the CAD device 41 for each predetermined thickness. Divide into layers. Then, the data conversion device 42 outputs the image data of each layer to the control unit 45 of the manufacturing device 43 (step S11). The control unit 45 reads the image data of each layer and sets the irradiation amount of the laser beam for each pixel (corresponding to each position of the movable base 46) of each layer (step S12).

Next, the control unit 45 drives the powder supply unit 47. As a result, as shown in FIG. 10A, the powder supply unit 47 forms the metal powder layer 51 having the predetermined thickness described above on the upper surface of the movable table 46 (step S13). That is, a metal powder is prepared. Next, the control unit 45 drives the laser light source 44. As a result, the laser light source 44 irradiates the metal powder layer 51 with a predetermined amount of the laser beam according to the irradiation amount of the laser beam set by the control unit 45 (step S14). As a result, as shown in FIG. 10B, a part of the metal powder layer 51 is melted, and the part is sintered.

Next, the control unit 45 determines whether or not the sintering operation has been performed in relation to all the layers (step S15). When the sintering operation is not completed (No in step S15), the control unit 45 drives the movable base 46 and displaces the movable base 46 downward by the same value as the thickness of the metal powder layer 51 (step S16). ).

The control unit 45 drives the powder supply unit 47 again. As a result, the powder supply unit 47 forms the metal powder layer again (step S13). Next, the control unit 45 drives the laser light source 44. As a result, the laser light source 44 irradiates a predetermined amount of the laser beam to a predetermined portion of the metal powder layer according to the irradiation amount of the laser beam set by the control unit 45 (step S14). As a result, a part of the metal powder layer is melted, and the part is sintered. In this way, by varying the amount of metal powder melted depending on the location, each part of the induction heating coil 1 except the insulator 4 is formed at a desired density.

In the manufacturing apparatus 43, steps S13 to S16 are repeated until the sintering operation is performed in relation to all the layers. As a result, as shown in FIG. 10 (c), the metal powder layers n, n + 1, n + 2, ..., (N is a positive integer) are laminated to form the induction heating coil 1. In this laminating step, the support portion 50 is formed in addition to the induction heating coil 1.

The support unit 50 is provided in order to prevent the coil unit 3 as a protrusion protruding from the power supply unit 2 from being displaced with respect to the metal powder layer 51 due to its own weight during modeling in the laminating process. It is provided. In the present embodiment, the induction heating coil 1 is formed by the manufacturing apparatus 43 so as to be in an upside down state. Therefore, the coil portion 3 is shaped while being supported from below by the support portion 50.

Then, when the control unit 45 determines that the sintering work has been performed on all the layers (Yes in step S15), the sintering work is completed. In the post-treatment (step S4) after the modeling step with reference to FIG. 8, the operator removes the induction heating coil 1 formed on the movable table 46 from the movable table 46 and adheres to the induction heating coil 1. It includes a process of removing unnecessary metal powder from the induction heating coil 1. Further, in this step, the support portion 50 is removed from the induction heating coil 1 by using a cutter (not shown) or the like. Step S4 is an example of the "cutting step" of the present invention. Further, in the post-processing step (step S4), the insulator 4 is attached to the power supply unit 2. As a result, the induction heating coil 1 is completed.

As described above, according to the present embodiment, the cooling water channels 5 in the coil section 3 and the power supply section 2 are formed by using the metal additive manufacturing method. In the metal additive manufacturing method, an arbitrary three-dimensional shape can be formed by repeatedly performing the work of solidifying the molten metal after selectively applying heat to the metal powder layer 51 to melt it. Therefore, even if the cooling water passage 5 formed in the coil unit 3 and the power supply unit 2 has a complicated shape, the power supply unit 2 and the coil unit 3 can be made of a single component. Therefore, in order to connect the coil unit 3 itself, the power supply unit 2, and the coil unit 3, it is not necessary to provide a brazed portion between the power supply unit 2 and the coil unit 3. Therefore, the brazing work that requires skill is not required. Moreover, if the metal additive manufacturing method is used, the induction heating coil 1 having the same shape can be mass-produced with high mechanical accuracy. Therefore, the induction heating coil 1 can be mass-produced with uniform dimensions.

Moreover, since brazing is not required to form the coil portion 3 itself, and it is not necessary to braze the coil portion 3 and the power supply portion 2, the thermal distortion of the coil portion 3 itself due to the brazing work and the thermal distortion of the coil portion 3 itself are caused. No thermal strain occurs between the power supply unit 2 and the heating coil unit 3. Therefore, a dedicated jig for suppressing such thermal strain is unnecessary, and the induction heating coil 1 can be manufactured more easily.

Further, since the work for setting the above jig for brazing is not required, the production efficiency of the induction heating coil 1 can be further increased. Moreover, the metal additive manufacturing method has a high degree of freedom in setting the shape. Therefore, the degree of freedom in setting the shape of the induction heating coil 1 in order to achieve the optimum heat treatment of the object to be processed 100 can be increased. Further, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of the thermal stress in the coil portion 3 and in the connecting portion 13 between the power supply portion 2 and the coil portion 3. Therefore, the life of the induction heating coil 1 can be extended.

Therefore, according to the present embodiment, the induction heating coil 1 can be manufactured so as to have a longer life. Further, the induction heating coil 1 can be manufactured more easily and with higher accuracy, and the production efficiency of the induction heating coil 1 can be further increased.

Further, according to the present embodiment, the volume of the support portion 50 removed by machining in the post-treatment step after the laminating molding step is small, and the yield of the material of the induction heating coil 1 can be further increased. As a result, the manufacturing cost of the induction heating coil 1 can be suppressed through the reduction of the material cost. Further, in the laminating molding step, the weight of the heating coil portion 3 can be reduced by changing the density of the melted portion. As a result, the material of the coil portion 3 can be reduced, so that the material cost of the induction heating coil 1 can be further reduced. Further, the life of the induction heating coil 1 can be further improved by reducing the stress acting on the connection portion 13 between the power supply portion 2 supporting the coil portion 3 and the coil portion 3. Furthermore, the shape of the coil portion manually finished by a skilled worker can be easily reproduced (reverse engineering) by the additive manufacturing method.

Further, according to the present embodiment, when the induction heating coil 1 is formed by the metal additive manufacturing method, the support portion 50 that supports the coil portion 3 of the induction heating coil 1 is formed. Then, the induction heating coil 1 has a cut rear portion 14 after the support portion 50 is cut. According to this configuration, in the support portion 50, the coil portion 3 as a protruding portion protruding from the power supply portion 2 is displaced with respect to the metal powder layer 51 by its own weight during modeling by the metal additive manufacturing method. Can be used to suppress the occurrence of. Thereby, the dimensional accuracy of the induction heating coil 1 can be further improved.

In particular, in the present embodiment, the coil portion 3 has a thickness smaller than the thickness of the power supply portion 2 and is formed in a shape protruding from the power supply portion 2, and the support portion 50 is guided by the metal additive manufacturing method. The coil portion 3 is supported when the heating coil 1 is formed. According to this configuration, the induction heating coil 1 having the thin coil portion 3 can be formed more accurately.

Further, according to the present embodiment, the cross-sectional area of the connecting portion 13 between the power supply portion side water channel 15 and the coil portion side water channel 16 continuously changes as the cooling water advances in the traveling direction F1. The shape of the connection portion 13 between the power supply portion 2 and the coil portion 3 changes significantly, and the thermal stress tends to increase locally. Around such a connecting portion 13, the shape of the cooling water channel 5 is a shape that continuously changes. As a result, the bias of the thermal stress at the connection portion 13 can be suppressed. Therefore, the life of the induction heating coil 1 can be extended.

Further, according to the present embodiment, the coil unit 3, the power supply unit 2, and the cooling water channel 5 are integrally formed by using a single member. According to this configuration, it is not necessary to provide a brazed portion in either the coil portion 3 itself or between the power supply portion 2 and the coil portion 3. Therefore, thermal distortion between the power supply unit 2 and the heating coil unit 3 due to the brazing operation does not occur. Therefore, a dedicated jig for suppressing such thermal strain is unnecessary, and the induction heating coil 1 can be manufactured more easily. Further, since the work for setting the above jig for brazing is not required, the production efficiency of the induction heating coil 1 can be further increased. Further, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of the thermal stress in the coil portion 3 and in the connecting portion 13 between the power supply portion 2 and the coil portion 3. Therefore, the life of the induction heating coil 1 can be extended.

Further, according to the present embodiment, the heating coil unit 3 and the power supply unit 2 are not provided with brazed portions. Therefore, even in the connecting portion 13, the brazed portion is not provided. Therefore, thermal distortion of the heating coil unit 3 and the power supply unit 2 due to the brazing operation does not occur. Therefore, since a brazed portion that is a discontinuous portion in terms of electrical resistance is not required, it is possible to reduce the bias of the thermal stress in the heating coil portion 3 and the power supply portion 2. Therefore, the life of the induction heating coil 1 can be extended. Further, the heating coil unit 3 and the power supply unit 2 are integrally formed of the same metal material having conductivity. Therefore, compared to the conventional coil unit and power supply unit formed by brazing a plurality of metal materials, electricity in all the parts in the heating coil unit 3 and the power supply unit 2 per unit volume. The variation in resistivity is small. Further, the variation in the electrical resistivity (Ω · m) per unit volume (1 mm ³ ) is at least 10% or less in all the parts in the heating coil unit 3 and the power supply unit 2, and in particular, the present embodiment. Is 5% or less, and is at least 1/2 of the variation in the electrical resistivity of the coil portion when formed using silver wax. Therefore, in the expansion and contraction of the heating coil unit 3 and the power supply unit 2 due to heat, the variation in the amount of expansion and contraction in the heating coil unit 3 and the power supply unit 2 is unlikely to occur. Therefore, fatigue failure in the heating coil unit 3 and the power supply unit 2 can be suppressed, and the life of the induction heating coil 1 can be further extended by extending the life of the heating coil unit 3 and the power supply unit 2.

Here, a qualitative comparison is made between the induction heating coil 1 and the conventional induction heating coil 1'(not shown). The induction heating coil 1'has a configuration in which the power supply portion and the coil portion are formed separately and then the power supply portion and the coil portion are joined by brazing. It has almost the same shape.

The electrical resistivity of each part of the induction heating coil 1 except for the insulator 4 is about 1.7 × ^10-8 Ω · m. On the other hand, for the induction heating coil 1', the electrical resistivity of the brazed portion is about 9.1 × ^10-8 Ω · m, and the electrical resistivity of each portion other than the brazed portion and the insulator is about 1. .7 × ^10-8 Ω · m. As described above, in the induction heating coil 1', there is a difference of about 5 times in the electrical resistivity between the brazed portion and the other conductors.

As shown in FIG. 11A, the variation amount Δ1 of the electrical resistivity in the vicinity of the connection portion 13 between the power supply portion 2 and the coil portion 3 in the front-rear direction of the induction heating coil 1 is about 1%. It will be a small value. The variation in the electrical resistivity of the induction heating coil 1 is at least 1/2 or less, 1/3 or less, 1/4 or less, as compared with the variation in the electrical resistivity of the induction heating coil 1'having a brazed configuration. The electrical resistivity can be reduced to 1/5 or less. One of the reasons why the variation amount Δ1 is not zero is the variation in the porosity inside the material when the power supply unit 2 and the coil unit 3 are formed by the metal additive manufacturing method.

By the way, among the JIS silver waxes specified in JIS (Japanese Industrial Standards), the components of BAG-1A are Ag: 50%, Cu: 15.5%, Zn: 16.5%, Cd: 18%. It has become. The conductivity (IACS) of this BAG-1A is 25%. The components of JIS silver wax BAG-1 are Ag: 45%, Cu: 15%, Zn: 16%, and Cd: 24%. The conductivity (IACS) of this BAG-1 is 19%.

The above-mentioned conductivity is the ratio of the conductivity when the conductivity of the standard annealed copper wire defined by IACS (International Annealed Copper Standard) is 100%. That is, the conductivity of the above BAG-1A and BAG-1 is about 1/4 to 1/5 that of copper, and the electrical resistivity is large. That is, the variation in the electrical resistivity in the induction heating coil 1 can be made much smaller than the variation in the electrical resistivity in the induction heating coil 1'in which the brazing material is used.

11 (a) is a graph schematically showing the electrical resistivity of each part of the induction heating coil 1 according to the first embodiment, and FIG. 11 (b) is a graph showing the electrical resistivity of each part of the induction heating coil 1 according to the first embodiment. It is a graph which shows typically the electrical resistivity of each part of. In FIGS. 11 (a) and 11 (b), the horizontal axis indicates the position of each part in the front-rear direction, and the vertical axis indicates the value of electrical resistivity.

On the other hand, as shown in FIG. 11B, the variation amount Δ2 of the electrical resistivity in the vicinity of the connection portion between the power supply portion and the coil portion in the front-rear direction of the induction heating coil 1'is several tens of percent. It becomes. Therefore, in the induction heating coil 1', large expansion and contraction are repeated at the brazed portion each time the heating and cooling of the induction heating coil 1'are repeated, and fatigue fracture is likely to occur. On the other hand, the induction heating coil 1 of the present embodiment is not provided with a brazed portion. Therefore, in the induction heating coil 1, even if the induction heating coil 1 is repeatedly heated and cooled, large expansion and contraction do not occur at the connection portion 13, and fatigue fracture is unlikely to occur. Therefore, it is clear that the durability of the induction heating coil 1 is excellent.

Further, the manufacturing process of the induction heating coil 1'is more complicated than the manufacturing process of the induction heating coil 1, and the manufacturing of the induction heating coil 1 becomes much easier. More specifically, the conventional induction heating coil 1'manufacturing process involves (1) designing the coil portion, (2) designing the brazing portion, and (3) using a jig for suppressing distortion during brazing. Design, (4) Manufacture of this jig, (5) Manufacture of power supply part and coil part, (6) Brazing of power supply part and coil part, (7) To ensure dimensional accuracy Eight steps of finishing processing and (8) pickling (removal of oxide film) after the brazing step are required.

In the design process of the brazed portion in (2) above, skill is required for the design for avoiding stress concentration as much as possible. Further, in each of the manufacturing processes of the power supply unit and the coil unit in (5) above, machining is required for each part, resulting in a decrease in yield (loss of material due to shaving). Further, in the brazing step of (6) above, the brazing work cannot be redone due to the failure of brazing, and the skill of the worker is required. Further, in the finishing process of the above (7), it takes time and effort to remove the thermal strain generated in the brazing process.

On the other hand, as described above, the manufacturing process of the induction heating coil 1 includes (1) a design process (step S1), (2) a modeling direction setting process (step S2), and (3) a laminated modeling process (3). Only four steps are required: step S3) and (4) a post-processing step (step S4) such as removing the support unit 50.

Further, since the steps S1 to S3 are all performed by using a computer, the induction heating coil 1 with high accuracy can be mass-produced with a high yield while the influence of the skill level by the worker is extremely suppressed. In the post-treatment step of (4) above, the support portion 50 is removed as an unnecessary member, but the amount of the support portion 50 is small and the influence on the material yield of the induction heating coil 1 is small. I'm done.

In the above-described embodiment, in the cooling water channel 5, a smooth shape is realized around the connection portion 13 between the power supply unit side water channel 15 and the coil unit side water channel 16. However, this does not have to be the case. For example, as shown in FIG. 12, in the cooling water passage 5, a step portion 13a may be formed around the connection portion 13 between the power supply portion side water passage 15 and the coil portion side water passage 16.

[Second Embodiment]
FIG. 13 is a perspective view of the induction heating coil 1A according to the second embodiment of the present invention. FIG. 14 is an enlarged perspective view of the coil portion 3 of FIG. FIG. 15 is a side view of the coil portion 3. FIG. 16 is a plan view of the coil portion 3. In the following, a configuration different from that of the first embodiment will be mainly described, and the same components as those of the first embodiment will be designated by the same reference numerals and the description thereof will be omitted.

With reference to FIGS. 13 to 16, the induction heating coil 1A has a power supply unit 2, a coil unit 3, an insulator 4, a cooling water channel 61, and a second cooling water channel 62. The portion of the induction heating coil 1A other than the insulator 4 is formed by using the metal additive manufacturing method.

The cooling water channel 61 is provided as a water channel through which cooling water for cooling the coil portion 3 passes. In the present embodiment, the cooling water enters the induction heating coil 1A from the power supply unit 2, is returned to the power supply unit 2 through the coil unit 3, and is discharged from the power supply unit 2 to the outside of the induction heating coil 1A. Will be done. In the present embodiment, the cooling water channel 61 has a uniform cross-sectional shape. That is, the cross-sectional shape of the cooling water channel 61 orthogonal to the traveling direction F1 of the cooling water channel 61 is constant at any position in the traveling direction F1. In the present embodiment, the cross-sectional shape of the cooling water channel 61 is a substantially perfect circular shape.

The cooling water channel 61 has a water channel 63 on the power supply unit side and a water channel 64 on the coil unit side.

The water channel 63 on the power supply unit side is a water channel formed in the power supply unit 2, and supplies cooling water to the water channel 64 on the coil unit side and discharges cooling water from the water channel 64 on the coil unit side.

The power supply unit side water channel 63 has a first water channel 65R formed in the first divided body 6R and a second water channel 65L formed in the second divided body 6L.

The first water channel 65R and the second water channel 65L are formed in a symmetrical shape. The first water channel 65R and the second water channel 65L are formed below the corresponding ribs 9 and 9 of the lower wall portions 12 and 12 of the corresponding divided bodies 6R and 6L, respectively, and are linear along the front-rear direction. Extends to. The cross-sectional area of each of the water channels 65R and 65L (the area in the cross section orthogonal to the traveling direction F1) is the cross-sectional area of the second cooling water channel 62 in the second water channel 73 on the power supply unit side (the cross section orthogonal to the traveling direction F1). Area) is set smaller than.

The first water channel 65R and the second water channel 65L are opened behind the corresponding rear walls 7 and 7, respectively, and the corresponding first linear portion 66R and the second linear portion 66L of the coil portion side water channel 64 are provided. It is connected to the.

The coil portion side water channel 64 has a first linear portion 66R, a second linear portion 66L, and an undulating portion 67.

The first linear portion 66R is a portion continuous with the first water channel 65R of the water channel 15 on the power supply unit side, and extends in a straight line with the first water channel 65R. The first linear portion 66R is connected to the undulating portion 67 below the tapered surface 3f of the inner peripheral surface 3d of the coil portion 3.

The second linear portion 66L is a portion continuous with the second water channel 65L of the power supply unit side water channel 15, and extends in a straight line with the second water channel 65L. The second linear portion 66L is connected to the undulating portion 67 below the tapered surface 3f of the inner peripheral surface 3d of the coil portion 3.

The undulating portion 67 is formed as a meandering portion that undulates in the vertical direction (thickness direction of the coil portion 3) as it advances along the circumferential direction C1. The undulating portion 67 is arranged adjacent to the inner peripheral surface 3d of the coil portion 3, and is configured to be capable of cooling a region of the coil portion 3 in the vicinity of the inner peripheral surface 3d that generates a particularly large amount of heat. The undulating portion 67 is located below the tapered surface 3f of the inner peripheral surface 3d of the coil portion 3.

The undulating portion 67 has an entrance portion 68, a plurality of first arch portions 69, a plurality of second arch portions 70, and an exit portion 71.

The entrance portion 68 is provided as a portion connected to the first linear portion 66R. The entrance portion 68 is formed so as to extend downward while facing inward in the radial direction. The entrance portion 68 is connected to the first arch portion 69.

In the present embodiment, the first arch portion 69 and the second arch portion 70 are alternately arranged in the circumferential direction C1, and due to the continuous shape of the first arch portion 69 and the second arch portion 70, the first arch portion 69 and the second arch portion 70 are arranged in the vertical direction. An undulating portion 67 is formed on the surface.

The first arch portion 69 is a portion formed in a U shape when viewed along the radial direction R1 of the coil portion 3. The first arch portion 69 is arranged near the lower end portion of the coil portion 3. The second arch portion 70 is a portion formed in a U shape that is upside down when viewed along the radial direction R1 of the coil portion 3. The second arch portion 70 is arranged in the middle portion of the coil portion 3 in the vertical direction, and is located above the first arch portion 69.

As described above, one end of the first arch portion 69 is continuous with the entrance portion 68. The other end of the first arch portion 69 is continuous with one end of the second arch portion 70. Further, the other end of the second arch portion 70 is continuous with one end of the next first arch portion 69. In this way, the first arch portion 69 and the second arch portion 70 are alternately connected along the circumferential direction C1. Then, at the other end 3b of the coil portion 3, the first arch portion 69 is connected to the outlet portion 71.

The outlet portion 71 is provided as a portion connected to the second linear portion 66L. The outlet portion 71 is formed so as to extend outwardly and upward in the radial direction R1 from the first arch portion 69 at the other end portion 3b of the coil portion 3. A second cooling water channel 62 is arranged adjacent to the cooling water channel 61 having the above configuration.

The second cooling water channel 62 is provided as a water channel through which cooling water for the object to be processed (refrigerant for the object to be processed) for cooling the object to be processed 100 induced and heated by the coil portion 3 passes. The second cooling water channel 62 is connected to the injection nozzle 72, and the cooling water that has passed through the second cooling water channel 62 is injected from the injection nozzle 72 to the object 100 to be processed. That is, after the object to be processed 100 is heated by the induction heating coil 1A, cooling water is sprayed onto the object to be processed 100 from the injection nozzle 72 to perform quenching treatment of the object to be processed 100.

The second cooling water channel 62 has the same shape as the cooling water channel 5 of the first embodiment. More specifically, the second cooling water channel 62 has a second water channel 73 on the power supply unit side and a second water channel 74 on the coil unit side.

The second water channel 73 on the power supply unit side is a water channel formed in the power supply unit 2, and supplies cooling water to the second water channel 74 on the coil unit side.

The second water channel 73 on the power supply unit side has a first water channel 75R formed in the first division body 6R and a second water channel 75L formed in the second division body 6L.

The first water channel 75R is provided as a cooling water supply path to the second water channel 74 on the coil portion side. Since the shape of the first water channel 75R is the same as the shape of the first water channel 21R of the induction heating coil 1, detailed description thereof will be omitted.

The second water channel 75L is provided as a cooling water supply path to the second water channel 74 on the coil portion side. Since the shape of the second water channel 75L is the same as the shape of the second water channel 21L of the induction heating coil 1, detailed description thereof will be omitted. A second water channel 74 on the coil portion side is formed in the first water channel 75R and the second water channel 75L having the above configuration.

The coil portion side second water channel 74 is provided to supply cooling water to the injection nozzle 72. Further, the second water channel 74 on the coil portion side is configured to cool the coil portion 3 in cooperation with the cooling water channel 61. The second water channel 74 on the coil portion side is an endless annular water channel formed as a whole, and is formed around the central axis of the coil portion 3. The second water channel 74 on the coil portion side is arranged so as to surround the undulating portion 67 of the cooling water channel 5. The shape of the second water channel 74 on the coil portion side is the same as the shape of the water channel 16 on the coil portion side of the cooling water channel 5 of the induction heating coil 1.

More specifically, the second water channel 74 on the coil portion side has an inlet 31A, an outer peripheral side surface 32A, an inner peripheral side surface 33A, an upper surface 34A, a lower surface 35A, an outlet 36A, a first expansion portion 37A, and a first. It has two expansion portions 38A.

The shapes of the inlet 31A, the outer peripheral side surface 32A, the inner peripheral side surface 33A, the upper surface 34A, the lower surface 35A, the outlet 36A, the first expansion portion 37A, and the second expansion portion 38A are each induced heating according to the first embodiment. It has the same shape as the corresponding inlet 31, outer peripheral side surface 32, inner peripheral side surface 33, upper surface 34, lower surface 35, outlet 36, first expansion portion 37, and second expansion portion 38 of the coil 1.

In the second cooling water channel 62 having the above configuration, the cooling water from the second water channel 73 on the power supply unit side flows toward the second water channel 74 on the coil unit side, and further, from the second water channel 74 on the coil unit side. It flows to the injection nozzle 72.

The coil portion 3 of the injection nozzle 72 is opened toward the portion facing the object to be processed 100 during the heat treatment of the object to be processed 100, and the cooling water for the object to be processed is injected onto the object to be processed 100.

A large number of injection nozzles 72 are formed along the circumferential direction C1 and the vertical direction (thickness direction of the coil portion 3). In the present embodiment, each injection nozzle 72 extends from the coil portion side second water channel 74 to the inner peripheral surface 3d of the coil portion 3 along the radial direction R1, and is open to the inner peripheral surface 3d. The injection nozzle 72 forms a columnar space. The injection nozzles 72 are provided at equal intervals in the vertical direction and at equal intervals in the circumferential direction C1.

A part of the injection nozzle 72 is formed in a tubular shape arranged so as to avoid the undulating portion 67 of the cooling water channel 61. Further, some of the injection nozzles 72 are formed in a tubular shape extending so as to penetrate the undulating portion 67.

As described above, according to the second embodiment, the undulating portion 67 of the cooling water channel 61 extends so as to undulate in the thickness direction of the coil portion 3 as it advances along the circumferential direction C1. According to this configuration, a larger contact area between the coil portion 3 and the cooling water can be secured. Therefore, since the heat generated in the coil portion 3 can be more efficiently absorbed by the refrigerant, it is possible to more reliably suppress the bias of the thermal stress due to the overheating of the coil portion 3. Further, the cooling water channel 61 can be made thinner (smaller). The ease of manufacturing the induction heating coil 1A having the cooling water channel 61 having such a three-dimensional and complicated shape becomes remarkable by using the additive manufacturing method.

Further, according to the second embodiment, the injection nozzle 72 can inject the cooling water for the object to be processed into the object 100 to be processed. According to this configuration, the object to be treated 100, which has been heat-treated by induction heating by the coil unit 3, can be cooled by the cooling water for the object to be processed. As described above, the ease of manufacturing the induction heating coil 1A having the second cooling passage 62 in addition to the cooling water channel 61 becomes remarkable by using the additive manufacturing method.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. The present invention can be modified in various ways as long as it is described in the claims.

(1) For example, in the above-described embodiment, a mode in which the coil portion 3 is an endless annular shape has been described as an example. However, this does not have to be the case. The coil portion 3 may have a shape capable of inducing and heating the object to be processed 100, and may have, for example, an arbitrary shape having a curved portion, a U-shape, or a spiral shape. It may be formed in. Further, the coil portion may have a shape in which a plurality of rings are arranged in the axial direction of the coil portion 3 (a plurality of turns shape).

(2) Further, in the above-described embodiment, both ends of the connecting portion 13 between the power supply portion 2 and the coil portion 3 in the circumferential direction C1 are provided as a stepped shape in a plan view, but this is true. It does not have to be. For example, as shown in FIG. 17, the connecting portion 13 may be formed in a shape in which the cross-sectional area continuously increases toward the heating coil portion 3 side. In this case, the outer surface 13c of the connecting portion 13 is formed in a smooth arc shape, and stress concentration due to thermal stress is less likely to occur.

(3) Further, in the above-described embodiment, the embodiment in which the support unit 50 is not formed in the power supply unit 2 of the induction heating coil 1 has been described as an example. However, this does not have to be the case. For example, when the power supply unit 2 and the coil unit 3 are in the horizontal position when completed, the support unit 50B may be installed below the power supply unit 2.

When the power supply unit 2 and the coil unit 3 are formed in a horizontal position, the power supply unit 2 and the coil unit 3 are formed together with the support unit 50B as shown in FIG. 18A. The support portion 50B is formed in a plate shape below the power supply portion 2 and the coil portion 3. Then, the boundary portion 55 between the support portion 50B, the power supply portion 2, and the coil portion 3, which is shown by the alternate long and short dash line, which is an imaginary line in FIG. 18A, is cut in the post-processing step. As a result, as shown in FIG. 18B, the support portion 50B is cut off from the power supply portion 2 and the coil portion 3. The post-excision portion 14B is formed in a portion corresponding to the boundary portion 55. The boundary portion 55 is located on the lower end surface 12b of the lower wall portion 12 and the lower end surface 3h of the coil portion 3.

On the other hand, when the power supply unit 2 and the coil unit 3 are formed so as to be in a vertical position, as shown in the bottom view of FIG. 19A, the power supply unit is in the vertical position together with the support unit 50B'. 2 and the coil portion 3 are formed. The support portion 50B'is formed so as to fill a hollow portion behind the coil portion 3 (in FIG. 19A, below the coil portion 3). That is, the support portion 50B'is formed in a portion located below the coil portion 3 in the vertical position, and supports the coil portion 3. Then, the boundary portion 55'between the support portion 50B'and the power supply portion 2 and the coil portion 3 shown by the alternate long and short dash line in FIG. 19A is cut in the post-processing step. As a result, as shown in FIG. 19B, the support portion 50B'is cut off from the power supply portion 2 and the coil portion 3. The post-excision portion 14B'is formed in the portion of the coil portion 3 corresponding to the boundary portion 55'. The boundary portion 55'is located on the side surface of the lower wall portion 12 of the power supply portion 2 and the rear surface of the coil portion 3.

The present invention can be widely applied as an induction heating coil and a method for manufacturing an induction heating coil.

1,1A Induction heating coil 2,2B Power supply unit 3g Upper end surface (predetermined part of induction heating coil)
3 Coil part 5,61 Cooling water channel (refrigerant passage)
13 Connections 14, 14B, 14B'After excision 15 Power supply side waterway (power supply side passage)
16 Coil side waterway (coil side passage)
50, 50B, 50B'Support part 62 Second cooling water channel (second refrigerant passage)
63 Waterway on the power supply side (passage on the power supply side)
64 Coil side waterway (coil side passage)
67 Undulating part 72 Injection nozzle 100 Object to be processed C1 Circumferential direction F1 Travel direction

The present invention relates to a process for the production of induction heating coil.

By view of the above circumstances, an object of the present invention, the induction heating coil, can be prepared as a longer life, it is to provide a manufacturing how the induction heating coil.

(1) In order to solve the above problems, the induction heating coil according to a certain aspect of the present invention is a coil portion including a curved shape portion having an inner diameter portion and an outer diameter portion, and induces and heats an object to be processed. a coil unit for a power supply unit for supplying power to the coil unit, is disposed in the power supply unit and the said coil section, and the refrigerant passage for supplying refrigerant to the coil unit, Ru with a In a method for manufacturing an induction heating coil, in order to reduce the variation in heat generation in the coil portion due to the energization of the coil portion and to reduce the deviation of the thermal stress in the coil portion, the coil portion also has the curved shape portion. By being formed by the metal lamination molding method including the coil portion, the coil portion is integrally formed as a single member by a conductive metal material, and all the parts of the coil portion are not brazed. ..

According to this configuration, the refrigerant passage in the coil portion is formed by using the metal additive manufacturing method. In the metal additive manufacturing method, an arbitrary three-dimensional shape can be formed by repeatedly performing the work of solidifying the molten metal after selectively applying heat to the powder metal layer to melt it. Therefore, even a refrigerant passage formed in the coil portion is a complicated shape, it is possible to make a coil portion in a single component. Therefore, filtration earthenware pots with portions need not be provided in the coil portion. Therefore, the brazing work that requires skill is not required. Moreover, if the metal additive manufacturing method is used, it is possible to mass-produce induction heating coils of the same type with mechanical accuracy. Therefore, it is possible to mass-produce induction heating coils with uniform dimensions.

Moreover, since the brazing have required to form the coil portion itself, the coil unit itself due to the brazing operation thermal distortion optic lobe, no. Therefore, a dedicated jig for suppressing such thermal strain is unnecessary, and the induction heating coil can be manufactured more easily.

Further, since the work for setting the above-mentioned jig for brazing is not required, the production efficiency of the induction heating coil can be further increased. Moreover, the metal additive manufacturing method has a high degree of freedom in setting the shape. Therefore, it is possible to increase the degree of freedom in setting the shape of the induction heating coil in order to achieve the optimum heat treatment of the object to be processed. Further, since the brazed part as the electrical resistance discontinuous portions is not required, it can be reduced the deviation of the thermal stress definitive in the coil portion. Therefore, the life of the induction heating coil can be extended.

(2) Preferably, the coil portion and the power supply portion are integrally formed as a single member by the metal additive manufacturing method, and the coil portion and all parts of the power supply portion are brazed. Does not have.

(3) good Mashiku the variation in electrical resistivity at all sites within the coil portion is 5% or less.

(4) Preferably, the coil portion, the power supply portion, and the refrigerant passage are integrally formed as a single member by the metal lamination molding method, and the coil portion, the power supply portion, and the above. All parts of the refrigerant passage do not have a brazed configuration, and the refrigerant passage has a power supply portion side passage formed in the power supply portion and a coil portion side passage formed in the coil portion. The variation in the electrical resistance at the connection between the power supply side passage and the coil portion side passage is 1% or less.

(5) Preferably, at the time of additive manufacturing by the metal additive manufacturing method, a support portion that supports a predetermined portion of the induction heating coil is formed by the metal additive manufacturing method, and the support portion is cut off after the additive manufacturing method. ..

(6) Preferably, the coil portion is formed in an arc shape when viewed along the central axis direction of the coil portion, and the power supply portion includes a main body connected to the coil portion and is of the coil portion. When viewed along the central axis direction, the main body extends in a predetermined longitudinal direction along the radial direction of the coil portion and extends in a direction orthogonal to the longitudinal direction as a lateral direction, and the coil portion extends from the main body. The support portion is formed in a protruding shape, and the support portion supports the coil portion as the predetermined portion and does not support the power supply portion when the induction heating coil is formed by the metal lamination molding method. It is formed in.

(7) Preferably, the power supply unit includes a protruding portion protruding to one side of the coil portion in the direction of the central axis of the coil portion, and the protruding portion is downward in the metal lamination molding method. The power supply unit and the coil unit including the protrusion are formed.

(8) Preferably, the coil portion is formed in an arc shape when viewed along the central axis direction of the coil portion, and the power supply portion includes a main body connected to the coil portion and is of the coil portion. When viewed along the central axis direction, the main body extends in a predetermined longitudinal direction along the radial direction of the coil portion and extends in a direction orthogonal to the longitudinal direction as a lateral direction, and the coil portion extends from the main body. The coil portion is formed in a protruding shape, the coil portion is formed so that the central axis is vertically oriented at the time of formation by the metal lamination molding method, and the support portion is the induction heating coil by the metal lamination molding method. Is formed so as to support the entire one end surface of the coil portion and the one end surface of the power supply portion in the direction of the central axis as the predetermined portion.

(9) Preferably, the coil portion is formed in an arc shape when viewed along the central axis direction of the coil portion, and the power supply portion includes a main body connected to the coil portion and is of the coil portion. When viewed along the central axis direction, the main body extends in a predetermined longitudinal direction along the radial direction of the coil portion and extends in a direction orthogonal to the longitudinal direction as a lateral direction, and the coil portion extends from the main body. It is formed in a protruding shape, and when viewed along the central axis direction of the coil portion, the width of the main body in the lateral direction is set shorter than the width of the coil portion in the lateral direction, and the metal. In the laminated molding method, the coil portion and the main body are formed in a state where the central axis of the coil portion and the longitudinal direction are horizontal, and the support portion is the predetermined portion at the time of laminated molding by the metal laminated molding method. As a result, the coil portion is formed so as to support a region from one end of the coil portion in the lateral direction to a connection portion between the coil portion and the main body and the main body.

The present invention provides a method of manufacturing the induction heating coil can be widely applied.

Claims (11)

A coil for induction heating of the object to be processed,
A power supply unit for supplying power to the coil unit and
A refrigerant passage which is arranged in the power supply unit and the coil unit and for supplying a refrigerant to the coil unit is provided.
An induction heating coil, characterized in that the coil portion, the power supply portion, and the refrigerant passage are formed by using a metal additive manufacturing method. The induction heating coil according to claim 1.
At the time of forming the induction heating coil by the metal additive manufacturing method, a support portion for supporting a predetermined portion of the induction heating coil is formed.
The induction heating coil is characterized in that it has a rear portion after cutting the support portion. The induction heating coil according to claim 2.
The coil portion has a thickness smaller than the thickness of the power supply portion and is formed in a shape protruding from the power supply portion.
The induction heating coil is characterized in that the support portion is formed so as to support the coil portion as the predetermined portion when the induction heating coil is formed by the metal additive manufacturing method. The induction heating coil according to any one of claims 1 to 3.
The refrigerant passage includes a power supply portion side passage formed in the power supply portion and a coil portion side passage formed in the coil portion.
An induction heating coil characterized in that the cross-sectional area of the connection portion between the power supply portion side passage and the coil portion side passage changes continuously as the refrigerant advances in the traveling direction. The induction heating coil according to any one of claims 1 to 4.
The refrigerant passage includes a coil portion side passage formed in the coil portion.
The coil portion side passage has an undulating portion and has an undulating portion.
An induction heating coil, characterized in that the undulating portion extends so as to undulate in the thickness direction of the coil portion as it advances along the circumferential direction of the coil portion. The induction heating coil according to any one of claims 1 to 5.
A second refrigerant passage through which the refrigerant for the object to be processed for cooling the object to be processed, which is induced and heated by the coil portion, passes, and an injection nozzle are further provided.
The second refrigerant passage and the injection nozzle are formed by using the metal additive manufacturing method.
The injection nozzle is connected to the second refrigerant passage, and the injection nozzle is connected to the second refrigerant passage.
The injection nozzle has a coil portion opened toward a portion facing the object to be processed during heat treatment of the object to be processed, so that the refrigerant for the object to be processed can be injected onto the object to be processed. The characteristic induction coil. A coil unit for inducing heating an object to be processed, a power supply unit for supplying electric power to the coil unit, and a power supply unit and a coil unit arranged in the coil unit to supply a refrigerant to the coil unit. A method for manufacturing an induction heating coil, which comprises a metal lamination molding step of forming a refrigerant passage by using a metal lamination molding method. The method for manufacturing an induction heating coil according to claim 7.
In the metal lamination molding step, a support portion for supporting a predetermined portion of the induction heating coil is formed.
A method for manufacturing an induction heating coil, which further comprises a cutting step of cutting the support portion. A coil for induction heating of the object to be processed,
A power supply unit for supplying power to the coil unit and
A refrigerant passage which is arranged in the power supply unit and the coil unit and for supplying a refrigerant to the coil unit is provided.
An induction heating coil, characterized in that the coil portion, the power supply portion, and the refrigerant passage are integrally formed by using a single member. A coil for induction heating of the object to be processed,
A power supply unit for supplying power to the coil unit and
It is provided with a refrigerant passage provided in the power supply unit and the coil unit to form a gap for supplying the refrigerant to the coil unit.
The coil portion is integrally formed of the same conductive metal material.
All parts of the coil part do not have a brazed configuration and
An induction heating coil, characterized in that the variation in electrical resistivity per unit volume (mm ³ ) of the metal material is 5% or less. The induction heating coil according to claim 10.
The coil portion and the power supply portion are integrally formed of the same metal material.
All parts of the coil part and the power supply part do not have a brazed configuration.
An induction heating coil, characterized in that the variation in electrical resistivity per unit volume (mm ³ ) of the metal material is 5% or less.

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