JPH10275993A - Magnetic shielding body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress heat generated by a current, which is made to flow through the interior of a shielding body, by a method wherein a conductor is divided into a plurality of rectangular shapes or rectangle shapes and is constituted in a state that the divided conductors are assembled into one solid body in a state that the divided conductors are insulated from each other. SOLUTION: As the example of a magnetic shielding body applied to a magnetic shielding of a molten steel electromagnetic stirring device, which is installed in an iron manufacturing factory, the magnetic shielding body to be used is constituted into a structure, wherein a 6-mm thick magnetic shielding steel plate 1 is divided into four in a rectangular shape. Insulators 6, such as a Bakelite and a mica, are respectively applied or pasted on or to the respective end edge parts of the divided iron plates as an insulator in the gaps between the divided iron plates and the iron plates are fixed to each other. The important matter here is that when the conductor 1 is divided, the conductor 1 is divided into a plurality of rectangular forms or rectangle forms in such a way as the intersect the flow direction of a current, which is made to flow through the interior of the conductor. That is, as the current can be divided more, the current is effective to a reduction in a calorific value. As the current, which is made to flow through the interior of the conductor, is proportioned to the area of the conductor, the smaller the area of the conductor is made, the more the current can be inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic shield in which the amount of heat generated by a magnetic field of a conductor is suppressed.

[0002]

2. Description of the Related Art Conventionally, various magnetic shields have been used to prevent radio interference such as wall materials including window members such as buildings, vehicles, and shielded rooms, or electronic equipment cases, etc. Proposed. For example, there are an electromagnetic shielding glass, a magnetic shielding plate having a sandwich structure sandwiching a special resin, and a magnetic shielding plate having an infinite number of voids inside a steel plate, and are used in many fields.

[0003] However, these electromagnetic shielding glasses and magnetic shielding plates have been regarded as problematic in the frequency range of 0.5 to 1 GHz, that is, the prevention of radio interference, the leakage of confidential information, and the obstacle in the measurement environment. Electromagnetic stirrers and induction heaters for molten steel, which are very commonly installed in factories and machining plants, are magnetic shield plates with a sandwich structure sandwiching the special resin described above, or countless voids inside the steel plate. When a magnetic shielding plate provided with is used, a current flows through the magnetic shielding plate to generate a magnetic field, and the generation of the magnetic field raises the heat of the magnetic shielding plate to about 400 ° C. In such an environment, when precision machinery, measuring equipment, computer equipment, OA equipment, etc. are installed in the vicinity, in addition to obstacles due to magnetic flux leakage, safety for workers working due to generated heat The environment has become extremely dangerous for sex, and these problems are still unsolved.

[0004]

SUMMARY OF THE INVENTION The present invention provides a magnetic shield in which the amount of heat generated by the current flowing through the shield is suppressed.

[0005]

That is, the present invention is characterized in that a conductor is divided into a plurality of strips or rectangles, and the divided conductors are combined in a state of being insulated from each other. A state in which the conductor is divided into a plurality of strips or rectangles so as to intersect the direction of the current flowing in the conductor, and the divided conductors are insulated from each other. A magnetic shield characterized by having a structure in which the magnetic shields are combined.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of a magnetic shield according to the present invention, which is applied to a magnetic shield of an electromagnetic stirring device for molten steel installed in an ironworks. The magnetic shield used here is a steel plate 1 for magnetic shielding having a thickness of 6 mm (here, a normal SS-based iron plate is used) divided into four rectangular sections (2, 3, 4, 5). An insulator 6 such as bakelite, mica or the like is applied or stuck to each edge portion as an insulator in a gap between them, and is fixed. The magnetic shield configured as described above is installed in such a form that it is laminated on a top plate attached to the upper part of the electromagnetic stirrer or mounted on a base.

What is important here is that when dividing the conductor, the conductor is divided into a plurality of strips or rectangles so as to intersect with the direction in which the current flowing in the conductor flows.
For example, as shown in FIG. 2, the sheet is divided into strips in a direction C crossing a direction A of the current flowing in the conductor (a direction in which the current flows in the longitudinal direction of the conductor). The direction in which the conductor is divided may be divided in a direction crossing the current flowing through the conductor in the width direction of the conductor shown in FIG. 2, but the division in the C direction allows more current to be divided, It is more effective in reducing the amount of heat generated. Since the current flowing in the conductor is proportional to the area of the conductor, it is based on the principle that the smaller the area of the conductor, the more the current can be suppressed.

When the magnetic shielding effect manufactured under the frequency of 3 Hz was tested on the magnetic shield manufactured according to the present invention and the conventional single-plate iron plate, the conventional single-plate iron plate was heated to about 400 ° C. by a magnetic field. On the other hand, in the magnetic shield of the present invention, the amount of generated heat could be suppressed to 200 ° C. or less, which is 50% or less.

[0009]

The magnetic shield of the present invention can greatly reduce the amount of heat generated by the current flowing through the conventional conductor, and can be easily manufactured at a low cost.

[Brief description of the drawings]

FIG. 1 is a schematic view schematically showing a magnetic shield according to the present invention.

FIG. 2 is a schematic diagram showing a direction in which a current flows in a conductor and a direction in which the conductor is divided.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Conductor 2, 3, 4, 5 ... Divided conductor 6 ... Insulator A: Direction of current flow in conductor C: Dividing direction

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Keisuke Fujisaki 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division

Claims (2)

[Claims] 1. A magnetic shield, wherein a conductor is divided into a plurality of strips or rectangles, and the divided conductors are combined in a state of being insulated from each other. 2. A structure in which a plurality of strips or rectangles are divided so as to intersect with a direction of a current flowing in a conductor, and the divided conductors are combined in an insulated state. And a magnetic shield.