JPS625022Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a power supply bus for a high frequency induction heating device.

The power bus connecting the high-frequency power output side of a large-capacity high-frequency induction heating device and the matching board is usually the first
As shown in Figure a, a configuration is used in which conductor bars 1 and 1 are connected in parallel with a space to ensure insulation, or they are connected with an insulating bolt or the like (not shown) with an insulator 2 interposed between them. , one conductor bar 1 is connected to a normal high voltage side output terminal of a high frequency power supply, and the other conductor bar 1 is connected to the other output terminal of the high frequency power supply. When an alternating current flows through this power supply bus (, indicates the current polarity), magnetic flux is generated and a magnetic field (alternating magnetic field) is generated, as well as so-called electromagnetic radiation in the medium wave region as shown by the arrow in Figure 1b. Therefore, when a high-frequency large current is supplied from a high-frequency power source to a matching board through the power bus, there is a problem that radio wave interference occurs over a considerable distance.

This type of problem can be solved by connecting the high-frequency power supply and the matching board with a coaxial cable, but since the power bus for induction heating equipment carries high power and high voltage current, it is extremely difficult to manufacture. difficult,
Even if it were manufactured, it would be very expensive.

The present invention was made in view of the above-mentioned conventional problems. Three conductor bars are arranged in parallel, and the two outer conductor bars are formed into a "shape" so that they almost surround the central conductor bar. By using a structure in which the two outer conductor bars are electrically treated as one conductor bar when connecting to a high-frequency power supply and a matching panel, it is almost as effective as a coaxial cable in terms of radio interference. It is an object of the present invention to provide a power supply bus for a high frequency induction heating device that can significantly reduce generation and is extremely inexpensive.

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

In FIG. 2a, 3A, 3B, and 3B are conductor bars, and an insulator 4 is interposed between the central conductor bar 3A and both outer conductor bars 3B, 3B, and insulating bolts or the like (not shown) are used. They are tied parallel to each other. The outer conductor bars 3B, 3B are wider than the center conductor bar 3A, and are shaped like a letter with a bent side edge S on one side, and the bent side edge S is in the center. It straddles the conductor bar 3A and reaches the vicinity of the other opposing outer conductor bar.The cross-sectional area of the conductor bars 3B, 3B is the same as that of the conductor bar 3A.
It is approximately 1/2 of the cross-sectional area of .

When using this power bus, for example,
As shown in Figure b, the central conductor bar 3A connects to the high frequency power source of the high frequency induction heating device, such as the inverter INV.
is connected to one output terminal X of the matching board C and one input terminal Ru.

When high-frequency power flows through this power supply bus, at a certain moment, as shown in Figure 2c, an electromagnetic field H+ of electromagnetic waves is generated around the central conductor bar 3A as shown by the solid line, and around the right outer conductor bar 3B. A magnetic field H- of electromagnetic waves is generated as shown by the dotted line. Although not shown, the same applies to the left outer conductor bar 3B. The directions of the magnetic fields H+ and H- of the electromagnetic waves are opposite to each other, and the amount of current flowing through the outer conductor bars 3B and 3B is 1/2 of the amount of current flowing through the conductor bar 3A, so the magnetic field strength distribution of the electromagnetic waves is as follows. As shown in Figure 2 d, the magnetic field H+ of the electromagnetic waves radiated from the conductor bar 3A almost cancels out the magnetic field H- of the electromagnetic waves radiated by the conductor bar 3B on the right outer side in the right outer direction of the wide surface of the conductor bar 3B. , and almost cancels out the magnetic field of the electromagnetic waves radiated by the outer conductor bar 3B in the left outer direction of the wide surface of the outer left conductor bar 3B.

Furthermore, since the magnetic flux caused by the current flowing through the central conductor bar 3A passes through the bent side edges S of the outer conductor bars 3B, eddy currents are generated in the bent side edges S. Since the eddy current generates magnetic flux in a direction that cancels out the above magnetic flux, the outer conductor bar 3B,
The bent side edge S of 3B exhibits a magnetic shielding effect, and the electromagnetic waves leaking from between the outer conductor bars 3B and 3B are wider than when there is no bent side edge S. Reduce to

FIG. 3 shows another embodiment of the present invention, in which notches 3B1 having a certain width are formed at predetermined intervals in the longitudinal direction of the bent side edges S of the outer conductor bars 3B, 3B.
is provided.

In this way, the outer conductor bars 3B, 3B
Since it is easy to bend outward and inward with respect to its wide surface, there is an advantage that this can be easily done when the power bus needs to be arranged in a square shape, for example, rather than in a straight line. .

In this embodiment, an insulator 4 is interposed between the central conductor bar 3A and the outer conductor bars 3B, 3B, but the insulator 4 is not used, and an insulating space is simply secured to connect them in parallel. The same effect as before can be obtained when fixed to .

As described above, according to this invention, the outer conductor bars are arranged parallel to each other on both sides of the center conductor bar, and the outer conductor bars are shaped like a letter so that they surround the center conductor bar. As a result, electromagnetic radiation can be greatly reduced in all four areas, and radio interference caused by high-frequency induction heating equipment can be greatly reduced compared to when using a conventional power supply bus. Moreover, since the character-shaped conductor bar is easy to manufacture, it can be obtained at an extremely low cost, and its effects are great.

[Brief explanation of the drawing]

Figures 1a and b are conventional power busses for high frequency induction heating equipment, Figure 2a is a perspective view of an embodiment of the power bus for high frequency induction heating equipment according to the present invention, and Figure 2b is an example of use of the above embodiment. FIG. 2c is a diagram showing the radiation state of electromagnetic waves in the above embodiment, FIG. 2d is a diagram showing the magnetic field strength distribution of electromagnetic waves in FIG. 2c, and FIG. 3 is a diagram showing another implementation of the present invention. FIG. 3 is a perspective view of an example. 3A...Central conductor bar, 3B...Outer conductor bar, 3B1...Notch, 4...Insulator, S...
Bent side edge, INV……High frequency power supply, X, Y
...Output terminal.

Claims (1)

[Claims for Utility Model Registration] (1) A central conductor bar and outer conductor bars in a shape that surround it from both sides and extend in parallel are bundled with insulation between them, and the central conductor bar is A power supply bus for a high-frequency induction heating device, characterized in that the bar is connected to one output terminal of a high-frequency power source, and the two outer conductor bars are connected to the other output terminal. A power supply bus for a high-frequency induction heating device according to claim 1, wherein notches are formed in the bent side edges at predetermined intervals in the longitudinal direction.