JPH036907B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a cut core by cutting a bent laminate made of amorphous metal ribbon for magnetic material without substantially reducing its magnetic properties.

Amorphous metals are obtained by solidifying metals from a molten state without undergoing crystallization, and as a result of solidification through an ultra-high-speed cooling process, they are most commonly formed into ribbons, films, or fine powders. obtained in the form of

Among them, amorphous metal (either a single metal or an alloy) ribbon for magnetic materials is characterized by low iron loss in the high frequency range, and is used in various electrical devices such as transformers, motors, generators, meters, etc. has been found to be extremely useful as an iron core.

However, contrary to common sense, amorphous metal ribbons for magnetic materials are 4 to 5 times harder than crystalline metals, such as silicon steel sheets, and in some fields where they are used as magnetic materials for electrical equipment, annealing is required. , as this treatment not only makes it hard but also brittle.
It was thought to be almost impossible to cut the laminate without substantially degrading the magnetic properties using conventional cutting means alone. Moreover, depending on the application, the cut surfaces are required to be so smooth that it is impossible to discern with the naked eye whether or not light rays are leaking through the gap when the cut surfaces are butted against each other.

The present inventors thought that if the amorphous metal laminate is kept in a state where the shape does not substantially change when cutting, it may be possible to prevent the deterioration of magnetic properties due to cutting, and as a result of various studies, the present invention was arrived at. .

According to the method of the present invention, it is possible not only to cut the laminate while preserving its magnetic properties, but also to achieve a high degree of smoothness at the cut end.

The present invention interposes a cuttable object of a size and shape that does not touch the inner wall surface at least inside a bent laminate of amorphous metal ribbons for magnetic materials, and a solidifiable shape-fixing material is placed in the gap between the two. The present invention relates to a method for manufacturing a cut core, characterized in that the laminated bent body is cut together with the interlayer body after the laminated shape is fixed by tightly filling the laminated body and then solidifying the laminated body.

Of course, the outside of the bending body may also be fixed with a fixing material.

The most important point of the method of the present invention is that the shape of the laminate is fixed not by fitting a ready-made core, but by filling it with resin or the like. As a result, the shape-fixing material can adhere to the surface of the bent body to an extremely high degree regardless of the condition or shape of the surface, and also causes almost no distortion in the bent body during filling.
The objective is to cause almost no deterioration in magnetic properties.

Although it has been known in the past to interpose wooden cores, etc., the interlayer used in the method of the present invention is completely different from the core in that it does not prevent deformation of the laminated bent body. That is, in the method of the present invention, the interlayer body is required to have a size and shape that does not come into contact with the inner wall of the bending body, and therefore cannot substantially exhibit the function of maintaining the shape of the bending body.

Various roles can be considered for the interlayer in the method of the present invention, but typical ones include clogging of the cutting blade that occurs when cutting the shape-fixing material and removing the fixing material that firmly adheres to the side of the blade. can be mentioned. In other words, the adhesiveness of epoxy resins, etc., which are commonly used as shape fixing materials, makes cutting difficult and dulls the cutting blade, and this dulling of the cutting blade cuts the machinable interlayer. The effect of using an interlayer is that the problem can be resolved at the same time.

The material of the interlayer is not particularly limited, but since it will be cut together with the bending body, it usually does not need to be an expensive material. Furthermore, since it goes without saying that highly hard materials that cause severe wear on the cutting blade or brittle materials that are easily broken are not preferred, it is usually sufficient to use core scraps such as silicon steel.

Preferred materials from this point of view are usually iron or its alloys, such as mild steel, carbon steel, silicon steel, pearlite, and ferrite.

The shape of the spacer is not particularly limited, and any shape that can be accommodated without contacting the inside of the bending body can be used.
Incidentally, it is preferable that the interval between the bent inner wall and the outer wall of the intervening body be wide, in view of the convenience of charging the shape fixing material. For example, for a rectangular annular bent body with an inner major axis of about 5 cm and an inner minor axis of about 3 cm, the interval is usually set to about 5 mm. If at least one of the inner major axis and the inner minor axis is about 1/2 or less of the above value, the gap between the narrow part of the interleaving body and the bent body wall may be only about 1 mm, but in this case as well. , it goes without saying that the method of the present invention is applicable.

Further, from a practical point of view, it is preferable to select the thickness of the interlayer to be the same as that of the bending body, but if the thickness is a little too thick or too thin, it will not cause any problems in cutting. Therefore, it is usually about 0.5 to 1.5 times the thickness of the bent body.
It is sufficient to use an interlayer of twice the thickness.

The material for fixing the shape of the metal laminate used in the present invention is not limited to any material as long as it is solid when cut and liquid or grease-like when filled. This shape-fixing material is a synthetic material that does not easily deform during cutting, that is, after solidification, because it must function to maintain the shape of the laminate against the impact and pressing force of the cutting blade applied to the laminate. Moreover, it is required to have a caking property that is difficult to be crushed by impact. In addition, it is liquid or grease-like (paste-like) when filling.
This condition applies not only when the substance itself is liquid or grease-like, but even if the substance itself is solid, it can be changed to this state by adding an appropriate solvent or heating, etc. This also includes the case where the material can return to the above-mentioned solid state again upon cutting.

Resin can be cited as an example of a substance suitable for use as the shape fixing material. However, this shape fixing material is not limited to resin, and has a bending strength (measured by ASTM D 790) of 250 kg/cm ² or more when cutting, and a compressive strength (ASTM
D695 (measured at 10% strain point) If it shows a strength of 300Kg/cm2 or ^more , it can be used as a so-called resin, rubber,
Regardless of whether or not they contain a filler that does not interfere with cutting, they are suitable as the shape fixing material of the present invention.

Suitable examples of the thermosetting resin include epoxy resin, phenol resin, urethane resin, melamine resin, glyptal resin, and polyimide resin.
These resins do not need to exhibit their maximum strength, and can be included as suitable materials as long as they satisfy both the bending strength and compressive strength.

Thermoplastic resins include high-density polystyrene,
Examples include polysulfone, polyamide, polyethylene terephthalate, polyphenylene ether, polycarbonate, and ABS. Of course,
It may be a mixture of two or more of these.

In the method of the present invention, the inner side of a ring-shaped ("ring-shaped" in the present invention is not limited to a circular shape but also includes all "closed curved shapes") laminate made by stacking amorphous metal thin strips for magnetic materials. , install an intermediary body of a size and shape that does not come into contact with it, and after fixing the shape of the bent body by tightly filling the gap between the two with a specific fixing material, cut the annular laminate together with the intermediary bodies. By doing this, a pair of cut cores are manufactured. However, the object of the present invention is not limited to annular bodies; an interlayer body is installed inside a U-shaped body made by bending thin strips of unequal length, and both After fixing by tightly filling the fixing material between the gaps, both ends of the fixing material are cut to the required length, and a plurality of these are laminated, or a laminate of thin strips of unequal length is used to fix the material. It may be a U-shaped or C-shaped material.

A pair of annular cores can be formed by using two U-shaped laminates with aligned end faces, obtained by cutting both end faces of the material by the method of the present invention, facing each other.

In the present invention, it is preferable to perform a heat treatment on the surface after bending to remove internal strain.

(Example) Next, a method for manufacturing a cut core made of amorphous metal according to an example of the present invention will be described with reference to FIGS. 2 to 5.

First, as shown in FIG. 3, a cuttable object 2 of a size and shape that does not touch the inner wall surface is inserted inside the laminated bent body 1 of FIG. 2 made of an amorphous metal ribbon for magnetic material. . Next, as shown in FIG. 4, a shape fixing material 3 that can be solidified is filled into the gap between the laminate 1 and the cuttable object 2, and the shape of the laminate 1 is fixed by solidifying the material 3. After fixing, the laminate 1 is cut together with the interlayers 2 and 3 as shown in FIG.

(Example) Amorphous magnetic ribbon [Product name: Metglas
2605SC (manufactured by Allied, USA), width 12.5mm,
An annular laminate (long inner diameter 40 mm, short inner diameter 19 mm, lamination thickness 12.5 mm) made by winding 25 mm long, 11 mm wide, and 12.5 mm thick inside is placed approximately horizontally.
A 12.6 mm approximately rectangular steel plate (material: SC) was installed as an interlayer. The distance between the two is 4 mm at the shortest part and 7.5 mm at the longest part, and epoxy resin [trade name: R-140 (manufactured by Mitsui Petrochemical Epoxy Co., Ltd.)] is applied to this gap.
Inject a liquid product made by thoroughly mixing 100 g of amine-based curing agent [trade name: Q-691 (Mitsui Petrochemical Epoxy Co., Ltd.)] with 30 g at room temperature, and harden at room temperature for 24 hours. Ta. In addition, this epoxy resin R
The bending strength of −140 after curing is 340Kg/cm ² (ASTM
D 790), compressive strength is 480Kg/cm ² (ASTM
D 695 at the 10% strain point).

The resulting raw material core was cut along with the interlayer body by a rotary blade equipped with a resinoid blade in a plane including its axis to obtain cut cores (a pair of semicircular cores). By carefully removing the epoxy resin remaining inside the core so as not to distort the core, 148.4 g of cores (in a pair) were obtained.

When we measured the DC magnetic properties of the obtained core, we found that the saturation magnetic flux density was B ₁₀ =
The coercive force was 1.53 tesla (T), and the coercive force was Hc = 0.06 oersted (Oe), which was hardly lower than the value before cutting.

Next, we measured iron loss as an AC characteristic.

The measurement conditions were a frequency of 25 KHz, a magnetic flux density of 1000 G, a number of turns of n20, and a voltage of 28.3 V. When we started energizing the coil wound around the bent body, no change was observed in the voltage, but the current reached 147.5 mA immediately after energizing. At that time, the iron loss was 19.5W/Kg, but after 15 minutes of energization, the current increased to 149.4mA, and the iron loss decreased.
It decreased to 18.8W/Kg.

This iron loss was determined by experiment before cutting (voltage 28.2V, current
Since the iron loss is almost equal to 16.2 W/Kg at 112.0 mA), the deterioration of magnetic properties due to cutting and the shape of the cut end face did not pose any practical problems.

[Brief explanation of the drawing]

FIG. 1 shows a DC magnetic characteristic curve of a cut core manufactured by the method of the present invention. FIGS. 2 to 5 are perspective views of a cut core at each step for explaining a method for manufacturing a cut core made of amorphous metal according to an embodiment of the present invention.

Claims (1)

[Scope of Claims] 1. A cuttable object of a size and shape that does not touch the inner wall surface is interposed on the inside of a laminated bent body made of amorphous metal ribbon for magnetic material, and a solidified shape is fixed in the gap between the two. 1. A method for manufacturing a cut core, which comprises filling the laminate with a material, solidifying the material to fix the shape of the laminate, and then cutting the laminate together with the interlayer. 2 The shape fixing material exhibits a bending strength (according to ASTM D 790) of 250 kg/cm ² or more and a compressive strength (according to ASTM D 695, measured at 10% strain point) of 300 kg/cm ² or more when cut. A method for producing a cut core according to claim 1, characterized in that: 3. The manufacturing method according to claim 1 or 2, wherein the machinable interlayer body is made of metal. 4 The machinable interlayer body is carbon steel, mild steel, silicon steel,
The manufacturing method according to any one of claims 1 to 3, characterized in that the material is selected from pearlite or ferrite.