JPH0697646B2 - Amorphous magnetic alloy winding iron core - Google Patents

Description

TECHNICAL FIELD The present invention relates to an amorphous magnetic alloy wound iron core.

[Background of the Invention]

Recently, many attempts have been made to construct an iron core of an induction electric device such as a transformer by using a thin strip of an amorphous magnetic alloy to significantly reduce iron loss as compared with a conventional silicon steel sheet. Since the ribbon of this amorphous magnetic alloy is manufactured by jetting a melt of metal (Fe, Co, etc.) and non-metal element (B, Si, etc.) from a nozzle onto a drum rotating at high speed and then quenching it rapidly, Has a very thin thickness of about 30 μm and is hard and brittle. Since it is usually not easy to manufacture a laminated core using a ribbon of an amorphous magnetic alloy having such a property, it is generally used as a wound core, but if it is rapidly cooled, there is a large residual strain and the original Since low iron loss characteristics cannot be fully exhibited, annealing is always performed in advance. At this time, in order to align the 180 degree magnetic domains, the magnetic field is applied in the circumferential direction of the wound core.

Amorphous magnetic alloy thin band wound iron cores produced in this manner are combined with iron core blocks 1a to 1g as shown in JP-A-59-27511 and FIG. The leg part and the yoke part are partly straight lines and the other part is curved, and the radius of the curved part is almost oval with the outer circumference increasing, and its cross-sectional shape is as shown in FIG. Most of them were almost circular.

When it is attempted to manufacture an amorphous magnetic alloy ribbon winding core having a capacity of several tens kVA to several hundred kVA with such a structure, it is necessary to wind several thousand to tens of thousands of turns in a thin ribbon having a thickness of about 30 μm. I won't. For this reason, an excessive winding tightening phenomenon occurs in the curved portion of FIG. 10, and the compressive force F indicated by the arrow in the figure acts in the inward direction of the iron core window. Spoil.

In addition, when a large-sized wound iron core is manufactured with a thin strip of an amorphous magnetic alloy, a big problem occurs in terms of annealing. In normal annealing, it is performed under the condition that it is kept in an inert gas at a temperature of 350 to 400 ° C for 1 to 2 hours, but with a large wound core, the annealing furnace itself that creates such an atmosphere becomes large. Inevitably, the temperature distribution of each part of the wound iron core will be uneven. Therefore, over-annealing occurs on the outer layer side of the wound core and under-annealing occurs on the inner side, and the original low iron loss characteristics of the amorphous magnetic alloy ribbon cannot be fully exploited. It was an obstacle to the realization of a large wound iron core.

[Object of the Invention]

The present invention has been made in view of the above points, and an object thereof is to provide an amorphous magnetic alloy wound core capable of sufficiently ensuring the low iron loss characteristics of the ribbon of the amorphous magnetic alloy. It is what

[Outline of Invention]

That is, according to the present invention, a wound core of an amorphous magnetic alloy is wound, and a wound iron core having a substantially quadrangular shape in which four corners are curved and other straight lines are formed. The core blocks are composed of a combination of similar-shaped core blocks divided into a plurality of layers in the stacking direction, each core block is annealed independently, and the inner diameters of the corners of the curved portions of the respective core blocks are formed to be substantially the same. It is characterized in that the linear portions of the plurality of iron core blocks are brought into close contact with each other, and a substantially crescent-shaped void is formed in the curved portion corresponding to the corner portion of the iron core. In addition, it is possible to prevent an excessive winding tightening phenomenon at the curved portion.

[Examples of the Invention] Hereinafter, the present invention will be described based on illustrated examples. An embodiment of the present invention is shown in FIGS. 1 (A), (B), and (C) to FIG. Since the same parts as those of the prior art are designated by the same reference numerals, the description thereof will be omitted. In the present embodiment, the wound core is composed of a combination of similar core blocks 3a, 3b, 3c which are divided in the stacking direction of the ribbon 2 and the core blocks 3a, 3b, 3c are individually formed by annealing. And the corner portion inner diameter Ri and outer diameter Ro of the curved portion of each of the iron core blocks 3a, 3b, 3c are formed to be substantially the same, and the linear portions of the plurality of iron core blocks 3a, 3b, 3c are closely attached, and the iron cores Almost crescent-shaped voids 7 were formed in the curved portions corresponding to the corners. By doing so, overannealing and underannealing due to uneven temperature of each part of the winding core, which is a problem when integrally annealed because it was annealed independently, can be annealed without excess or deficiency, and the core corner Since a substantially crescent-shaped void 7 is formed in the curved portion corresponding to the above, it becomes possible to prevent an excessive winding tightening phenomenon in the curved portion, and the low iron loss characteristic of the thin strip 2 of the amorphous magnetic alloy is sufficiently exerted. It is possible to obtain an amorphous magnetic alloy wound iron core that can be secured.

That is, as shown in (A) of FIGS. 1 (A), (B), and (C), a ribbon 2 of an amorphous magnetic alloy is formed from a material hoop 4 into a plurality of iron cores each having a substantially rectangular shape and a predetermined size. Block 3
(3a, 3b, 3c) is wound and formed. Next, as shown in FIG. 2B, the exciting coil 5 is wound around each of the plurality of iron core blocks 3 formed to have a predetermined size, and a direct current or an alternating current is passed through the iron core blocks 3 to generate a magnetic flux. Annealing the iron core block 3 alone while flowing. At this time, the material is annealed in a container 6 filled with an inert gas in order to prevent the material from being oxidized. A plurality of iron core blocks 3a, 3b, 3c thus individually wound and annealed are assembled through necessary electric insulating materials and spacers for adjusting dimensions as shown in FIG. In this way, a plurality of iron core blocks 3a, 3b, 3c individually wound and annealed are assembled, but these plurality of iron core blocks 3a, 3b, 3c are formed only at the four corners as shown in FIG. The shape is similar to a curve, and the inner diameter Ri, the outer diameter Ro, and the laminated thickness t of the curved portion are substantially the same.

By doing so, as shown in FIG. 3, the wound iron core has three sets of substantially quadrangular iron core blocks 3a, 3b, 3c in which curved portions can be seen only at the four corners, and the three core blocks are closely attached to each other at the four linear corners. Then, a space 7 having a shape similar to a crescent shape is formed between the iron core blocks 3a, 3b, 3c to prevent the tightening phenomenon at the corners of the iron core, and It is possible to prevent the transmission of excessive compressive force, and it is possible to significantly alleviate the characteristic deterioration of the ribbon of the amorphous magnetic alloy. Also, since the three core blocks 3a, 3b, 3c are individually annealed as described above, over-annealing and under-annealing due to uneven temperature distribution of each part of the wound iron core, which is a problem when integrally annealed, is eliminated. In addition, it is possible to satisfy the severe annealing temperature condition required for the ribbon of the amorphous magnetic alloy and prevent the deterioration of the characteristics.

Further, as shown in FIGS. 4 and 5, the iron core blocks 3a, 3b, 3c are in close contact with each other at the straight line portion, and the voids 7 are generated at the curved portions at the corners. The width of the iron core is apparently widened by the number of. Therefore, a jig or the like can be arranged in the space 7 to facilitate the assembly of the iron core blocks 3a, 3b, 3c, and a member can be inserted into the space 7 so that stress that would deteriorate the characteristics of the iron core is not applied. Can also be supported. Further, even when the void 7 is left as it is, sufficient oil cooling or air cooling can be performed through the void 7, and heat generation inside the iron core, which is usually a problem, can be efficiently removed.

In this example, the inner diameters of the curved portions of the iron core members 3a, 3b, 3c
Although the case where Ri, the outer diameter Ro, and the laminated thickness t are substantially the same has been described, the present invention is not limited to this, and even if the inner diameters Ri of the curved portions are substantially the same, each core block 3a,
Voids 7 having a shape close to a crescent shape can be formed at the four corners between 3b and 3c, and the same effect as the above case can be obtained. In this case, it goes without saying that the iron core blocks 3a, 3b, 3c are formed in a substantially similar shape of a substantially quadrangle having curved corners. Further, the number of divided iron cores (the number of iron core blocks), the winding thickness, the inner and outer diameters, etc. can be appropriately selected according to the specifications and capacity of the wound iron core.

As described above, according to this embodiment, the following effects can be obtained.

(1) Since the core blocks having the same width are wound in the curved portion into a substantially quadrangular shape having substantially the same inner diameter and outer diameter, necessary jigs and processes are unified, and workability is significantly improved.

(2) Since the number of windings of the iron core (thin band) is reduced by the number of divisions of the iron core block, the winding tightening phenomenon, which has been regarded as a problem in the past, is greatly alleviated, and the deterioration of iron loss characteristics can be prevented.

(3) Since the iron core is divided, annealing is easy and local over-annealing and under-annealing due to temperature unevenness in the iron core are eliminated,
The original low iron loss characteristic of the ribbon of the amorphous magnetic alloy can be exhibited.

(4) Since voids can be formed at the four corners of the iron core, the voids can be utilized to efficiently assemble and support the iron core and further cool the inside of the iron core.

FIG. 6 shows another embodiment of the present invention. In this embodiment, a rigid member 8 having a rigidity higher than that of a ribbon of an amorphous magnetic alloy is arranged inside the three sets of iron core blocks 3a, 3b, 3c along the inner shape. By doing so, the mechanical strength of the wound core can be improved as compared with the case described above.

That is, the current thickness of the amorphous magnetic alloy ribbon is about 30 μm.
The core blocks 3a, 3b, due to their thinness and weak mechanical strength,
This is to solve the problem of deformation when assembling 3c and the inability to secure sufficient assembly accuracy. The material of the rigid member 8 is close in composition to the thin ribbon of the amorphous magnetic alloy and has rigidity, for example. A silicon steel plate is considered.

FIG. 7 shows still another embodiment of the present invention. In this embodiment, when the core width is the same and the winding thickness (lamination thickness) is large, the cores are divided into core blocks 3b ₁ and 3b ₂ and a void 7 is formed between them. Also in this case, the void 7 is formed in the portion where the winding thickness is large, and the same effect as the above case can be obtained.

That is, in the examples so far, the iron core was divided for each same iron core width (the iron core block was formed), but in the present embodiment, unlike the examples so far, when the winding thickness is large even with the same iron core width, The part with a large winding thickness is the core block 3b ₁ , 3b
_It is divided as shown in ₂ to form the void 7, which is particularly effective when the iron core becomes large. Further, in the examples so far, an example in which the iron core is divided only in the stacking direction is shown, but in the current amorphous magnetic alloy ribbon, the maximum iron core width is
Considering that the limit is about 200 mm, it is necessary to combine the iron cores in the width direction to obtain a predetermined iron core width. Even in such a case, the same configuration as that shown in the present embodiment is naturally possible.

FIG. 8 shows still another embodiment of the present invention. In this embodiment, a steel strip 9 having mechanical strength superior to that of the amorphous magnetic alloy ribbon is disposed inside the iron core blocks 3a, 3b, 3c. The steel strip 9 was formed from an amorphous magnetic alloy having excellent mechanical strength, which was several times to several tens times thicker than the usual thickness of 30 μm of a thin strip of amorphous magnetic alloy. By doing so, it is possible to prevent deformation of the iron core due to a winding tightening phenomenon that increases inside each iron core block 3a, 3b, 3c, and it is possible to easily assemble each iron core block 3a, 3b, 3c. it can. In this embodiment, the steel strip 9 is replaced by each iron core block.
Almost a small amount (relative to the laminated thickness t) is arranged inside 3a, 3b, 3c, but the ratio is the laminated thickness (roll thickness) t of each core block 3a, 3b, 3c and the stress due to tightening. Depending on the degree of
The arrangement amount is appropriately determined.

FIG. 9 shows still another embodiment of the present invention. In this example, the amorphous magnetic alloy 10 having an insulating film and excellent in mechanical strength was arranged inside the iron core blocks 3a, 3b, 3c. By doing this, each core block 3
It is possible to secure electrical insulation between a, 3b and 3c, and to prevent an increase in iron loss due to the eddy current flowing between the iron core blocks 3a, 3b and 3c.

〔The invention's effect〕

As described above, the present invention comprises a wound iron core, which is composed of a combination of similar-shaped iron core blocks divided into a plurality of strips in the laminating direction, and each iron core block is formed by annealing alone.
In addition, the inner diameters of the corners of the curved portions of the respective iron core blocks are formed to be almost the same so that the straight portions of a plurality of iron core blocks are closely contacted, and a substantially crescent-shaped void is formed in the curved portion that hits the iron core corners. As a result, over-annealing and under-annealing due to temperature non-uniformity in each part of the wound core, which is a problem when annealed integrally, is eliminated, and it is possible to anneal without excess or deficiency, and there is almost a crescent-shaped void in the curved part that hits the corner of the iron core. Since it is formed, it becomes possible to prevent an excessive winding tightening phenomenon at the curved portion, and it is possible to sufficiently secure the low iron loss characteristics of the ribbon of the amorphous magnetic alloy. You can get a winding iron core.

[Brief description of drawings]

FIGS. 1 (A), (B), and (C) show the assembly of a winding iron core by a plurality of iron core blocks of one embodiment of the amorphous magnetic alloy winding iron core of the present invention. FIG. FIG. 2 is a perspective view showing a wound state, (B) is a perspective view showing an annealed state of each iron core block, (C) is a perspective view showing an assembled state of each iron core block after annealing, and FIG. FIG. 3 is an enlarged plan view around the curved portion of FIG. 3, FIG. 3 is a plan view of the same embodiment, FIG. 4 is a sectional view taken along the line PP of FIG. 3, and FIG. 5 is a sectional view taken along the line QQ of FIG. FIG. 6 is an enlarged plan view around a curved portion of another embodiment of the amorphous magnetic alloy wound core of the present invention,
FIG. 7 is a sectional view of still another embodiment of the amorphous magnetic alloy wound iron core of the present invention, which corresponds to the line QQ in FIG. 3, and FIG. 8 is still another example of the amorphous magnetic alloy wound iron core of the present invention. FIG. 9 is an enlarged plan view around a curved portion of the embodiment of FIG. 9, FIG. 9 is a sectional view corresponding to the PP line of FIG. 3 of still another embodiment of the amorphous magnetic alloy wound iron core of the present invention,
FIG. 10 is a plan view of a conventional amorphous magnetic alloy wound iron core, and FIG. 11 is a sectional view taken along line XX of FIG. 2 ... Amorphous magnetic alloy ribbon, 3, 3a, 3b, 3b ₁ , 3b ₂ , 3
c ... iron core block, 4 ... material hoop, 5 ... excitation coil, 6 ... container, 7 ... void, 8 ... rigid member, 9 ...
… Steel strip, 10 …… Amorphous magnetic alloy, t …… Lamination thickness (roll thickness), g …… Space dimension.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Akiyo Yamaguchi 46 Tomioka, Nakajo-machi, Kitakanbara-gun, Niigata Prefecture 1 Nakajima Plant, Hitachi Ltd. (72) Masaru Sakamoto 46, Tomioka, Nakajo-machi, Kitakanbara-gun, Niigata Prefecture Address 1 Hitachi Ltd. Nakajo Plant (72) Inventor Koji Yamanaka 46 Tomioka, Nakajo-cho, Kitakanbara-gun, Niigata Prefecture 1 Address 1 Hitachi Ltd. Nakajo Plant

Claims (2)

[Claims] 1. A wound core of an amorphous magnetic alloy is wound, and a substantially quadrangular wound core having four curved corners and other straight lines is formed. It is composed of a plurality of iron core blocks that are divided in the stacking direction, respectively wound into a predetermined shape, and annealed separately, and the plurality of iron core blocks have a substantially quadrangular shape with curved corners. so,
And the inner diameters of the curved portions are formed to be substantially the same, and by forming a substantially crescent-shaped space between the curved portions of the plurality of core blocks, the inner peripheral surface of the iron core block located outside between the curved portions is An amorphous magnetic alloy wound iron core, which is formed so that pressure does not act on the outer peripheral surface of the core block adjacent to the inside. 2. Inside each of the plurality of core blocks,
A member that is more rigid than the ribbon forming the block,
The amorphous magnetic alloy wound iron core according to claim 1, which is arranged along the inner shape of the block.