JPH1197165A - High frequency heating coil device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To implement various types of heating with one kind of coils by making the shape of a coil part being a part generating a magnetic flux for induction heating a member to be heated, circular to be substantially identical in its size to the diameter of the flame of a gas burner at the time of heating a similar member to be heated. SOLUTION: A coil part 1b is a part to generate the magnetic flux for induction heating a member to be heated such as steel plate, and constituted such that its whole shape is made circular with a conduction portion 1d formed by spirally winding a steel plate and an insulation member 1e which is filled in a gap of the conduction portion 1d and therearound a core portion 1f serving as a magnetization path and being formed of a polyiron core is provided. The shape of the coil part 1b is made circular to be identical in its size to the diameter of flame of a gas burner at the time of heating a similar member to be heated so as to obtain similar heating as that of the gas burner. Accordingly, even if the heating shape changes no coil changing work is required, resulting in an improved workability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency heating coil device, and is particularly useful when applied to a steel plate bending apparatus.

[0002]

2. Description of the Related Art In general, a plate material such as a steel plate is bent by a press device or the like. For a complicated shape which is difficult to be processed by the press device, a heating bending method using a gas burner is employed. The operation using the gas burner has a problem that the working environment is bad due to noise, hot air, combustion gas and the like. For this reason, high-frequency induction heating has recently been studied. With this high frequency induction heating, an eddy current is generated in a member to be heated, for example, a steel plate by an electromagnetic induction action,
The heating is performed by utilizing the eddy current loss at this time. Therefore, high-frequency induction heating requires a high-frequency heating coil.

[0003] On the other hand, the heating shape in the heating bending of a steel sheet is various. That is, linear baking to heat linearly,
There are spot grilling for heating a predetermined point in a circular shape, weaving grilling for zigzag heating, and pine needle grilling for heating in a triangular shape.

[0004]

To cope with the various heating shapes as described above, various coils corresponding to the heating shape are prepared, and the coils may be replaced according to the heating shape. That is, an attachment method is conceivable. However, in the case of such an attachment type, many coils must be prepared according to the heating shape, and the coil must be replaced every time the heating shape changes. For this reason, problems such as a rise in equipment costs and a decrease in work efficiency occur.

The present invention has been made in view of the above-mentioned prior art, and has as its object to provide a high-frequency heating coil device capable of heating various shapes with one type of coil.

[0006]

According to the structure of the present invention, which achieves the above object, the shape of a coil portion which generates a magnetic flux for inductively heating a member to be heated is changed by heating the same member to be heated. It is characterized in that it is formed in a circular shape so as to be substantially equal to the diameter of the flame of the gas burner at the time.

[0007]

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

FIG. 1 is a perspective view showing the high-frequency heating coil device according to the present embodiment as viewed from below. As shown in FIG. 1, the high-frequency heating coil device 1 is mounted on a traveling base (not shown) of the high-frequency heating apparatus, and travels above the steel plate as a member to be heated by traveling of the traveling platform. It is configured to heat the levered steel sheet. Here, the high-frequency heating coil device 1 includes a disk portion 1a attached to the traveling platform or the like, a coil portion 1b fixed to the center of the disk portion 1a, and a large number of the disk portions 1a along the outer periphery of the coil portion 1b. It has a fixed steel ball portion 1c. The steel ball portion 1c abuts on the surface of the steel plate as a heating surface to smoothly move the high-frequency heating coil device 1 along the surface of the steel plate accompanying the movement of the traveling platform or the like, 1
It has a function of maintaining a constant clearance between b and the steel plate surface. Incidentally, the amount of heat input to the steel plate in the high-frequency heating depends on the current supplied to the coil portion 1b, its frequency,
The moving speed of the coil portion 1b and the clearance are uniquely determined as parameters. Therefore, in order to achieve uniform desired heating, it is essential to keep the clearance constant. In FIG. 1, reference numeral 2 denotes a nozzle, and when heating by the high-frequency heating coil device 1,
Water is supplied to the heating portion to cool the heating portion.

FIG. 2 shows a high-frequency heating coil device 1 shown in FIG.
It is a top view which expands and shows the coil part 1b of FIG. As shown in the drawing, the coil portion 1b is a portion that generates a magnetic flux for induction heating a member to be heated such as a steel plate. In the present embodiment, a conductive portion 1d formed by spirally forming a copper plate and the conductive portion 1d
And an insulating material 1e that fills the gap described above, so that the entire shape is circular, and a core portion 1f formed of a polyiron core and serving as a magnetic path is provided therearound. At this time, the circular shape of the coil portion 1b can be realized as a circular shape that is substantially equal to the diameter of the flame of the gas burner when heating the same member to be heated, so that the same heating as the heating by the gas burner can be realized. I have. For example, the diameter of the coil part 1c is 52 mm, and the diameter of the core part 1d is 84 mm.

FIG. 3 shows a high-frequency heating coil device 1 shown in FIG.
It is a sectional view in the vertical direction which expands and shows. As shown in the figure, the core portion 1f is a disk-shaped member having a concave portion facing the coil portion 1b, and is a member serving as a magnetic path of a magnetic flux formed by the coil portion 1b. The pipes 1g and 1h vertically penetrate the core portion 1f, and cool the coil portion 1b with cooling water flowing inside the core portion 1f. The disk portion 1a is a ring-shaped member, and the core portion 1f is fitted and fixed to the central portion thereof.

In the above-described embodiment, the insulating member 1e is cooled by cooling the coil portion 1b with the cooling water, so that the insulating member 1e can be formed of a heat-resistant resin.
The frequency of the induction heating current is, for example, 20 kHz to 3 kHz.
0 kHz is preferred. In the present embodiment, the member to be heated is a steel plate, and may be appropriately determined based on the penetration depth of the magnetic flux, the heating efficiency, and the like, but changes by several kHz depending on the heating conditions. The heating frequency range is generally about several kHz to 60 kHz for steel plates.
In some cases, 50 kHz to 100 kHz is preferable for z, aluminum alloy, and the like. Of course, the optimum frequency varies depending on the thickness of the member to be heated. The diameter of the coil portion 1b is 10 mm to 10 mm because the flame diameter of the gas burner of the conventional steel plate bending process by gas burner heating is about 52 mm as described above.
It is optimal for a steel plate of about 30 mm.

FIG. 4 shows the shape when a member to be heated is specifically heated by using the high-frequency heating coil 1 as described above.
4, the locus of movement of the coil portion 1b of the high-frequency heating coil 1 is indicated by a two-dot chain line. FIG. 4A shows the case of linear grilling. In the case of this linear baking, a linear baking of an arbitrary length can be performed by moving the coil portion 1b of the high-frequency heating coil 1 linearly. FIG. 4B shows the case of spot burning. In the case of this spot firing, a circular shape having an arbitrary radius can be fired by moving the coil portion 1b of the high-frequency heating coil 1 in a spiral shape. FIG. 4C shows the case of weaving baking. In the case of this weaving baking, it is possible to bake a waveform having an arbitrary width by moving the coil portion 1b of the high-frequency heating coil 1 zigzag. FIG. 4D shows the case of pine needle grilling. In the case of pine needle grilling, an arbitrary triangular shape can be grilled by moving the coil portion 1b of the high-frequency heating coil 1 while continuously changing the swing width.

As mentioned above, the shape of the grill can be any desired shape. In addition, the heating in this case includes not only the case of bending the steel plate but also all the heating processes such as strain relief and annealing.

[0014]

As described in detail with the above embodiments, according to the present invention, the shape of the coil portion, which is a portion for generating a magnetic flux for induction heating the member to be heated, is changed to the same shape as the member to be heated. Since the gas burner has a circular shape that is substantially equal to the diameter of the flame of the gas burner at the time of heating, it is possible to perform heating of any arbitrary shape with one coil as in the case of the heating processing using the conventional gas burner. For this reason, even if the heating shape changes, there is no need to replace the coil and there is no need to prepare a coil for each shape, and it is possible to realize low-cost heating workability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a high-frequency heating coil device according to an embodiment of the present invention when viewed from below.

FIG. 2 is an enlarged plan view showing a coil portion of the high-frequency heating coil device shown in FIG.

FIG. 3 is an enlarged vertical sectional view showing the high-frequency heating coil device shown in FIG. 1;

FIG. 4 is an explanatory view conceptually showing an example of a heating shape using the high-frequency heating coil shown in FIG.

[Explanation of symbols]

 1 High frequency heating coil device 1b Coil section

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuaki Ota 1-1, Akunouracho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries, Ltd. Nagasaki Shipyard (72) Inventor Fukumi Hamaya No.1, Akunoura-cho, Nagasaki, Nagasaki No. 1 Inside Nagasaki Shipyard, Mitsubishi Heavy Industries, Ltd. (72) Inventor Takijiro Shimamoto 5-717-1 Fukahori-cho, Nagasaki-city, Nagasaki Prefecture Inside Nagaishi Engineering Co., Ltd. 5-717 No. 1 Nagaishi Engineering Co., Ltd.

Claims (1)

[Claims] 1. A shape of a coil portion, which is a portion for generating a magnetic flux for induction-heating a member to be heated, is formed into a circular shape so as to be substantially equal to a diameter of a flame of a gas burner when a similar member to be heated is heated. A high-frequency heating coil device comprising: