JP6789638B2 - Induction heating coil - Google Patents

Description

The present invention relates to an induction heating coil that heats a plate-shaped member to be heat-treated.

A plate-shaped member such as a metal plate may be processed or surface-treated by heating it with an induction heating coil. The plate-shaped member arranged inside the induction heating coil is heated by an induced current generated by a magnetic field generated in the induction heating coil. In the plate-shaped member, the closer the distance to the induction heating coil is, the more easily it is affected by the magnetic flux and the higher the induction current. Therefore, uniform heating cannot be performed on a plate-shaped member in which a portion having a short distance from the induction heating coil and a portion having a long distance from the induction heating coil coexist.

Therefore, the induction heating device described in Patent Document 1 includes a primary coil and a secondary coil arranged between the primary coil and the metal plate as coils for inductively heating the metal plate. In the secondary coil, an induced current is generated by the magnetic field of the primary coil. As a result, the metal plate is heated not only by the primary coil but also by the secondary coil, and the temperature difference in the surface direction of the metal plate is reduced, so that the metal plate can be uniformly heated. ..

JP-A-2007-122924

In the technique of Patent Document 1, the induced current of the secondary coil is a current generated by the magnetic field of the primary coil, and is therefore smaller than the current flowing through the primary coil. Therefore, in order to increase the heating efficiency of the secondary choryl with respect to the metal plate, it is preferable to arrange the secondary coil and the metal plate close to each other. However, since the metal plate is usually held by a clamp or the like, it is not easy to hold the metal plate at an appropriate position at a short distance from the secondary coil.
Further, in the case of a thin metal plate, the induction-heated metal plate may warp and be distorted.

In view of the above circumstances, an induction heating coil that can perform uniform heating while suppressing distortion during heat treatment of a plate-shaped member is desired.

The characteristic configuration of the induction heating coil according to the present invention is an induction heating coil for heat-treating a plate-shaped member, which has a space inside for accommodating the plate-shaped member and generates a magnetic field by energization. a first conductor is a coil, the whole in the space is disposed, a planar second conductor induced current by the primary magnetic field more occurs energization of the first conductor flows, the second in the space A plurality of insulating spacing members provided on one surface of the conductor are provided, and the entire plate-shaped member is formed in the space via the plurality of spacing members. The plate-shaped member is induced and heated by the primary magnetic field and is also induced and heated by the secondary magnetic field generated from the induced current generated in the second conductor by the primary magnetic field. ..

By arranging the second conductor between the first conductor and the plate-shaped member, the plate-shaped member is induced and heated by the second conductor in addition to the first conductor, and the heating amount is increased. Here, when the plate-shaped member is heated only by the first conductor, the heating state differs depending on the portion of the plate-shaped member because the distance between the plate-shaped member and each part of the first conductor varies. On the other hand, by adding the second conductor, the influence of the first conductor on the plate-shaped member is alleviated, so that the plate-shaped member can be uniformly heated.
The second conductor has an insulating spacing member on at least one of the surfaces, and the plate-shaped member is in contact with and supported by the second conductor via the spacing member. As a result, the second conductors can be arranged at appropriate intervals with respect to the plate-shaped member, so that the heating efficiency of the plate-shaped member by the second conductor can be improved. Further, since the plate-shaped member is supported by the second conductor, it is possible to suppress the occurrence of distortion of the plate-shaped member.

Other characteristic feature of the induction heating coil according to the present invention, each of the plurality of spacing members is, lies in a sphere.

The plate-shaped member is induced and heated while being supported by the second conductor via an insulating spacing member. At this time, heat conduction may occur from the heated plate-shaped member to the space-holding member, and the heating efficiency of the plate-shaped member may decrease. Therefore, in this configuration, each of the plurality of spacing members are spherical. As a result, the contact area between the plate-shaped member and the space-holding member is reduced, and heat conduction between the two is suppressed. As a result, it is possible to suppress a decrease in heating efficiency due to the induction heating coil, and it is possible to maintain a uniform heating state for the plate-shaped member.

Another characteristic configuration of the induction heating coil according to the present invention is that there are two second conductors, which are arranged so as to face each other on both sides of the plate-shaped member, and the plurality of spacing members are two. The point is that each of the second conductors is provided on the side facing the plate-shaped member .

Induction heating can be performed on both sides of the plate-shaped member by the second conductor, and uniform heating can be performed on both sides of the plate-shaped member. Further, since the plate-shaped member is sandwiched by the second conductors that come into contact with both sides of the plate-shaped member, the warp of the plate-shaped member 1 can be further reduced.

Another characteristic configuration of the induction heating coil according to the present invention is that the first conductor can be expanded and contracted and deformed along the plane direction of the plate-shaped member.

If the first conductor can be expanded and contracted along the plane direction of the plate-shaped member as in this configuration, for example, when the first conductor is in a contracted state, the distance between the first conductors becomes narrower, so that the plate-shaped member as a whole becomes When the first conductor is in an elongated state, the distance between the first conductors is widened, so that the heating temperature of the plate-shaped member tends to be high or low depending on the portion. By expanding and contracting the first conductor in this way, the heating temperature distribution with respect to the plate-shaped member can be easily controlled, and the plate-shaped member can be heated more uniformly.
Another characteristic configuration of the induction heating coil according to the present invention is that it further includes a rotating device that rotates the second conductor with the direction perpendicular to the surface of the second conductor as the rotation axis.

It is a perspective view of 1st Embodiment. It is a side sectional view of 1st Embodiment. It is a top view of the 1st Embodiment. It is a side sectional view of the 2nd Embodiment. It is a figure which shows the 1st conductor in a contracted state. It is a figure which shows the 1st conductor in the extended state. This is a modified example of the interval holding member. This is a modified example of the interval holding member. This is a modified example of the interval holding member. It is a perspective view of another embodiment. It is a figure which shows the other embodiment.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

[First Embodiment]
As shown in FIGS. 1 to 3, the induction heating coil 10 is used when heating the plate-shaped member 1, and includes a first conductor 11 and a second conductor 12. The first conductor 11 is a coil having a space capable of accommodating the plate-shaped member 1 to be heated, and is connected to an induction heating power source (not shown). The second conductor 12 is formed in a flat plate shape, and is made of, for example, a copper plate.

A plate-shaped member 1 is arranged inside the first conductor 11, and a second conductor 12 is arranged between the first conductor 11 and the plate-shaped member 1. The second conductor 12 and the plate-shaped member 1 are arranged in order inside the first conductor 11, or are arranged inside the first conductor 11 in a state of being overlapped in advance.

When a current flows from the induction heating power source to the first conductor 11, a primary magnetic field is generated in the first conductor 11.
An induced current flows through the plate-shaped member 1 by this primary magnetic field, and the plate-shaped member 1 is heated. At this time, an induced current due to the primary magnetic field also flows through the second conductor 12, and the plate-shaped member 1 is induced and heated by the secondary magnetic field generated in the second conductor 12 accordingly.

In this way, the plate-shaped member 1 is induced and heated by the second conductor 12 in addition to the first conductor 11, so that the local bias of the induced current in the plate-shaped member 1 is corrected and the plate-shaped member 1 is relative to the plate-shaped member 1. Allows uniform heating. The second conductor 12 is a water-cooled type and can be heat-treated using a large amount of electric power. The second conductor 12 is preferably cooled by a water-cooled type from the viewpoint of cooling efficiency, but a cooling method other than the water-cooled type may be adopted.

The second conductor 12 is provided with an insulating spacing member 13 that supports the plate-shaped member 1 by abutting on at least one surface of the plate-shaped member 1. The interval holding member 13 is a sphere such as a ceramic ball, and a plurality of the interval holding members 13 are provided. The interval holding member 13 is fixed to one surface of the second conductor 12 by screwing, adhesion, or the like. Each of the spheres constituting the interval holding member 13 is provided with an abutting portion 14 that makes point contact with one surface of the plate-shaped member 1.

Since the second conductor 12 supports the plate-shaped member 1 via the insulating spacing member 13, the second conductor 12 can be arranged at an appropriate interval with respect to the plate-shaped member 1. As a result, the plate-shaped member 1 can be reliably induced and heated by the second conductor 12. Further, since the plate-shaped member 1 is supported by the second conductor 12, it is possible to suppress the occurrence of distortion of the plate-shaped member 1.

The plate-shaped member 1 is induced and heated while being supported by the second conductor 12 via an insulating spacing member 13. At this time, heat conduction may occur from the heated plate-shaped member 1 to the interval holding member 13, and the heating efficiency of the plate-shaped member 1 may decrease. Therefore, in this configuration, a plurality of contact portions 14 in which the interval holding member 13 makes point contact with the plate-shaped member 1 are provided. As a result, the contact area between the plate-shaped member 1 and the space-holding member 13 is reduced, and heat conduction between the two is suppressed. As a result, it is possible to suppress a decrease in heating efficiency due to the induction heating coil 10, and it is possible to maintain a uniform heating state for the plate-shaped member 1.

The second conductor 12 is mounted on the rotating device 20. Since the second conductor 12 and the plate-shaped member 1 rotate around the axis X of the rotating device 20, the variation in the distance between the first conductor 11 and the plate-shaped member 1 is corrected, so that the guide to the plate-shaped member 1 is induced. The heating can be made more uniform.

[Second Embodiment]
In the present embodiment, as shown in FIG. 4, the second conductor 12 is arranged on both sides of the plate-shaped member 1. The second conductor 12 is provided with an interval holding member 13 on each side facing the plate-shaped member 1. As a result, the plate-shaped member 1 is sandwiched by the second conductors 12 and 12 on both sides via the spacing member 13. The plate-shaped member 1 receives the weight of the second conductor 12 located on the upper side and is held between the second conductors 12 and 12 on both the upper and lower sides. The second conductor 12 located on the lower side of the plate-shaped member 1 is supported by the rotating device 20.

With this configuration, induction heating can be performed on both sides of the plate-shaped member 1 by the second conductor 12, and uniform heating can be performed on both sides of the plate-shaped member 1. Further, since the plate-shaped member 1 is sandwiched by the second conductor 12 that abuts on both sides of the plate-shaped member 1, the warp of the plate-shaped member 1 can be further reduced.

[Modified example of the second embodiment]
One or both of the second conductors 12 and 12 that sandwich the plate-shaped member 1 may be pressed and urged toward the plate-shaped member 1. In FIG. 4, the urging member of the second conductor 12 is shown by a broken line, and the plate-shaped member 1 is pressed by the urging member such as a spring. With this configuration, the holding force of the plate-shaped member 1 by the second conductor 12 is increased, so that the warp of the end portion of the plate-shaped member 1 can be suppressed more effectively.

[Other Embodiments]
(1) As shown in FIGS. 5 and 6, the first conductor 11 may be configured to be stretchable and deformable along the plane direction of the plate-shaped member 1. In FIGS. 5 and 6, the second conductor 12 is omitted to show the stretched state of the first conductor 11. The first conductor 11 is provided with, for example, an urging mechanism, a moving mechanism, and the like for expanding and contracting and deforming.

FIG. 5 shows a state in which the coil of the first conductor 11 is contracted, and the plate-shaped member 1 is heated as a whole because the distance between the coils is narrow. On the other hand, FIG. 6 shows a state in which the coil of the first conductor 11 is extended, and the interval between the coils is widened, so that the heating temperature of the plate-shaped member 1 tends to be high or low depending on the portion. By expanding and contracting the first conductor 11 in this way, the heating temperature distribution in the plane direction of the plate-shaped member 1 can be easily controlled. As a result, the plate-shaped member 1 can be efficiently induced and heated according to its shape and the portion to be heated.

(2) In the above embodiment, an example in which the second conductor 12 and the plate-shaped member 1 are rotated by the rotating device 20 is shown, but the second conductor 12 is placed without being rotated instead of the rotating device 20. A support may be provided and configured.

(3) In the above embodiment, an example in which the interval holding member 13 is made into a sphere is shown, but the shape of the interval holding member 13 is not specified as a sphere. As shown in FIG. 7, for example, the interval holding member 13 may have a chevron shape with the contact portion 14 at the top. In this way, the region of the contact portion 14 in contact with the plate-shaped member 1 can be made smaller. As shown in FIG. 8, the interval holding member 13 may be formed in a wavy shape in a side view, and the contact portion 14 may make line contact with the plate-shaped member 1. In this way, since the plate-shaped member 1 is continuously supported by the interval holding member 13, the plate-shaped member 1 can be stably held.

(4) As shown in FIG. 9, the interval holding member 13 may have a configuration in which the contact portion 14 is flattened and comes into surface contact with the plate-shaped member 1. As a result, the area in which the plate-shaped member 1 is supported by the spacing member 13 increases, so that the load per unit area of the plate-shaped member 1 becomes small. This makes it possible to prevent indentations and the like from being added to the surface of the plate-shaped member 1. In addition, the interval holding member 13 may be entirely prismatic or columnar.

(5) In the above embodiment, an example is shown in which the plate-shaped member 1 and the second conductor 12 are rotated while being placed on the rotating device 20 to make the heating by the first conductor 11 uniform. Alternatively, as shown in FIG. 10, a transport device 30 may be provided for carrying in and out the plate-shaped member 1 and the second conductor 12 into the inside of the first conductor 11. The transport device 30 and the rotating device 20 shown in the above embodiment may be provided together.

(6) In the above embodiment, the whole plate-shaped member 1 is heated by the induction heating coil 10, but a part of the plate-shaped member 1 may be heated by the induction heating coil 10.
For example, as shown in FIG. 11, in the plate-shaped member 1, the second conductor 12 is arranged to face the heated portion, and the mask material 15 having the same height as the second conductor 12 including the interval holding member 13 is placed in the non-heated portion. Place them facing each other. As a result, the plate-shaped member 1 can be partially heated by the induction heating coil 10.

(7) It is preferable that the induction heating coil 10 is housed inside the case, and the plate-shaped member 1 is induced and heated in a sealed state in which nitrogen gas is sealed in the case. By doing so, since oxygen is not present in the case, it is possible to prevent oxidation of the plate-shaped member 1 which is induced to be heated.

(8) In the above embodiment, an example in which the plate-shaped second conductor 12 is used is shown, but the second conductor 12 may be formed by a coil.

The induction heating coil according to the present invention can be widely used for heat treatment of plate-shaped members and the like.

1: Plate-shaped member 10: Induction heating coil 11: First conductor 12: Second conductor 13: Spacing member 14: Contact portion 15: Mask material 20: Rotating table

Claims (5)

An induction heating coil for heat treatment of plate-shaped members.
A first conductor, which is a coil that has a space for accommodating the plate-shaped member and generates a magnetic field by energization ,
Said whole space is arranged, the second conductive plate-shaped induction current flows due more results primary field to energization of the first conductor,
A plurality of insulating spacing members provided on one surface of the second conductor in the space are provided.
The entire plate-shaped member is supported by the second conductor in the space via the plurality of spacing members.
The plate-shaped member is an induced heating coil that is induced and heated by the primary magnetic field and is induced and heated by a secondary magnetic field generated from the induced current generated in the second conductor by the primary magnetic field . Each of the plurality of the spacing members is, the induction heating coil according to claim 1 which is spherical. There are two second conductors, which are arranged so as to face each other on both sides of the plate-shaped member .
The induction heating coil according to claim 1 or 2, wherein the plurality of spacing members are provided on the side of each of the two second conductors facing the plate-shaped member . The induction heating coil according to any one of claims 1 to 3, wherein the first conductor can be expanded and contracted and deformed along the plane direction of the plate-shaped member. The induction heating coil according to any one of claims 1 to 4, further comprising a rotating device for rotating the second conductor with a rotation axis perpendicular to the surface of the second conductor.

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