JPH0630309B2 - Amorphous core manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention mainly relates to a method for manufacturing an Aorhus core in a transformer or the like.

[Technical background of the invention and its problems] Amorphous is a non-crystalline state in which a high temperature phase is retained by rapidly cooling a metal / non-metal or a part of an organic polymer that originally crystallizes at room temperature from a molten state. Say the material. The manufacturing method is as follows.

(1) Cooling roll method A method of pouring a raw material in a heat-melted state into a water-cooled copper cylinder and rapidly cooling it on the surface of the rotating cylinder to form a sheet / ribbon shape, which is used for manufacturing a magnetic material.

(2) Glow discharge decomposition method / reactive sputtering method Both are methods of producing amorphous silicon. In the former case, gas molecules such as silane (SiH ₄ ) are discharged at 0.1 to 1 torr (Torr) and electrons are accelerated. The silane molecules are decomposed by the collision of and are detected on the substrate. The latter is a method in which silicon is sublimated in an atmosphere in which hydrogen is present and is agglomerated on the substrate.

(3) Thermal spraying method A method of spraying molten metal into fine particles into the air from a nozzle to obtain a flake-like or granular amorphous material, which is used for the production of plastic fillers.
Amorphous magnetic material is Ferrite (Fe ₈₁ B ₁₃ Si _3.5
C _2.5 ~% display ...... Metglas2605C ... Allied Chemical), cobalt _{{(CO 0.94 Fe 0.05) Si} 10 B 10 ~
Hitachi}, nickel-based {Ni _0.75 Fe _0.25 ) Si ₈ B ₁₄
~ Toshiba} is known. Optimum values of saturation magnetic flux density, coercive force, iron loss, and magnetic permeability can be obtained as the core characteristics of the transformer by changing the composition ratio.

Conventionally, a silicon steel sheet has been used as an iron core material, and it is necessary to compare the advantages and disadvantages with an amorphous iron core for practical use. The advantages of the amorphous iron core with respect to the silicon steel sheet are as follows.

From this table, it can be seen that there is little hysteresis loss at high frequencies. Further, FIG. 7 shows core loss characteristics in a magnetic field, P ₁ is a silicon steel sheet, and P ₂ is a core loss characteristic curve of an amorphous material. Amorphous from this figure
It can be seen that the core has less iron core loss in high magnetic fields.

Therefore, by selecting an appropriate composition for the amorphous material, the exciting current can be reduced in the vicinity of 3 KHz to 10 KHz, so that the temperature rise of the iron core due to loss can be reduced and the effective magnetic flux density in the iron core can be increased. As a result, the cross-sectional area of the high frequency transformer core can be halved according to the experiment for the silicon steel plate and the ferrite. Therefore, as shown in FIG. 5, a series resonant bridge inverter comprising an input power source section A comprising a switching and smoothing circuit, a main circuit B comprising a series resonant inverter, a control circuit C for B and a high voltage generating circuit D for obtaining a high voltage DC output. This is effective in reducing the weight of the inverter / transformer of the high frequency power supply and improving the voltage waveform.

However, the stacking factor (occupancy rate) of the amorphous iron core is about 0.75 (thickness 20 μm), and that of the silicon steel plate is 0.95 (thickness 50 μm). Precise alignment is necessary in connection with the above high magnetic flux density. On the contrary, if the surfaces are rough, the magnetic flux leakage will increase. Therefore, the cut surface of the amorphous core must be smooth. By the way, the interlayer adhesion of the amorphous iron core is performed in the same manner as the silicon steel plate, but the amorphous surface has chemical resistance and therefore the adhesiveness is not good. In addition, it has high hardness and elasticity, and its composition (bending) processing is also highly repulsive. Furthermore, the surface is smooth. In addition, when the amorphous core is hardened with an epoxy resin, a magnetostriction phenomenon occurs, which causes a problem that the distribution of the magnetic field is changed and the magnetic saturation density is lowered, and therefore it is necessary to use a soft rubber type epoxy resin for hardening. For the above reasons, the adhesive force between the amorphous laminated layers is weak, and if the core is cut by the conventional method using a tool such as a rotary blade or a wire saw, the laminated portion of the cut portion will be peeled off, as shown in FIG. Easier to spread. In such a state, butting of the core is impossible. Therefore, there is a drawback that a closed magnetic circuit cannot be formed as the core of the transformer. That is, this is because the processing force in the cutting work exceeds the adhesive force, and if such processing force is to be avoided, it is expected to select laser processing or electric discharge processing. However, the amorphous material is a material in which a high-temperature structure is forcibly fixed in an amorphous state at room temperature and is unstable in temperature. The Curie temperature of the amorphous material for the transformer core is about 400 ° C., and when it exceeds this temperature, recrystallization starts. When recrystallized, mechanical strength is lowered, many cracks are generated, and magnetic properties are also lowered. Since laser processing and electric discharge processing are also thermal processing in nature, deterioration of characteristics is likely to occur. The laser processing is a method of melting and cutting the material, and arc heat is generated in the electric discharge processing, and at the same time, the work becomes complicated because the interlayer adhesive is an insulator of the heat insulating part.
Therefore, it has been difficult to provide an amorphous iron core component with good characteristics by the conventional means.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object of the present invention is to manufacture an amorphous laminated core without deforming a processed cross section and without impairing magnetic characteristics.

[Summary of the Invention] The summary of the present invention for achieving the above-mentioned object is to smooth the abutting surface of an amorphous laminated core formed by interlayer adhesion with a rubber epoxy resin by a high-pressure fine water stream containing abrasive grains. It is a method for manufacturing an amorphous core, which is characterized by cutting.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is commercially available, for example, from Flow System Company (USA) and Sugino (Japan), and shows a pressure booster 3 operated by a hydraulic motor 2 driven by an electric motor 1 and an accumulator for maintaining a constant water pressure. 4 and Sweeper
Nozzle 6 that can move in all directions by joint 5
A more becomes high-pressure water generator, 1000Kg · f / cm ² ~5
The water 7 in the pipe is pressurized to 000 kg · f / cm ² and is connected to the nozzle 6 by the conduit 8. Normally 0.07mm as water
Jetted from a man-made sapphire nozzle with a diameter of ~ 0.5 mm. With this water jet, that is, a water jet, fiber materials such as paper cloth, plywood, foam rubber and Al flakes can be cut. However, in the case of hard glass and metal, the cutting performance is insufficient when left as water. Therefore, a nozzle as shown in FIG. 4 is used.

FIG. 4 is a drawing of an apparatus used when cutting a hard, high-density material such as glass or metal, in which 11 is a high-pressure water nozzle and 12 is high-pressure water. When high-pressure water is sprayed, 13 abrasives are attracted and water is mixed in 14 mixed layers.
Abrasive is mixed in the jet by weight. Many materials such as garnet, alumina, silica, iron sand, magnesia can be used as the abrasive. A water jet combined with these abrasives has a higher cutting effect than a simple water jet as it is.

FIG. 1 shows an iron core AS wound with an amorphous magnetic material. The wound core is cut from the central portion as shown by the dotted line to be in the state shown in FIG. In order to make a transformer, a coil is inserted into the cut surface, and the coil is butt-rebonded or held in a close contact state before use. However, if the cut surface of the iron core is spread out as shown in FIG. 6, not only will it hinder the coil assembly, but also the butt will be defective and the leakage magnetic flux will become large, making it impossible to manufacture a transformer.

On the other hand, the high-pressure water generator shown in FIG. 3 and the water portion combined with the abrasive shown in FIG.
If combined with a jet and cut like the example of the present invention, there is almost no processing application force to spread between the laminations, the cut surface is also smooth, and the fine wavy pattern at the lower end is only slightly polished. Mu. Further, no heat is generated during cutting, and no change occurs in the amorphous magnetic characteristics.

It is needless to say that the present invention is not limited to the above-mentioned embodiment but widely includes processing such as drilling and groove processing of the amorphous laminated material.

[Advantages of the Invention] As described above, according to the present invention, it is possible to easily process a transformer by cutting a wound iron core made of an amorphous magnetic material and to improve the characteristics of the machined surface. In particular, the larger the core cross-sectional area of a large capacity transformer, the more remarkable the effect of the present invention. Further, since the required working time is 7.5 mm / min (25 × 25 mm cross section), which corresponds to a sufficient processing speed for grinding, it is possible to provide a practical method for manufacturing an amorphous core.

[Brief description of drawings]

FIGS. 1 and 2 are amorphous iron cores, FIG. 3 is a high-pressure water generator, FIG. 4 is an abrasive composite nozzle, FIG. 5 is a circuit diagram of a bridge inverter high-frequency power supply device, and FIG. 6 is an example of defective core cutting. , FIG. 7 shows core loss characteristics in a magnetic field.

Claims (1)

[Claims] 1. A method for producing an amorphous core, characterized in that the abutting surface of an amorphous laminated core formed by adhesion between layers with a rubber epoxy resin is smoothly cut by a high-pressure thin water stream containing abrasive grains. .