JPH05251252A - Manufacture of amorphous transformer - Google Patents

Abstract

(57) [Abstract] [Purpose] To relieve brittleness and significantly reduce magnetic properties due to annealing of iron-based amorphous ribbon. [Structure] An iron-based amorphous ribbon 2 was used to form an iron core 3 of a transformer, the iron core 3 was annealed at a temperature of 300 to 320 ° C., and then subjected to the next step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an amorphous transformer in which an iron-based amorphous ribbon is used to form an iron core, and particularly to manufacture an amorphous transformer suitable for improving quality and productivity. Regarding the method.

[0002]

2. Description of the Related Art In a method for manufacturing an amorphous transformer in which an iron-based amorphous ribbon is used to form an iron core, first, the iron-based amorphous ribbon is wound and laminated, or a plurality of iron-based amorphous ribbons are laminated and cut. Form the iron core by stacking the stacked unit laminated blocks. Then, it is annealed to remove the strain of the iron core. However, depending on the annealing temperature, the iron-based amorphous ribbon becomes very brittle, and it is easy to break the iron core joint opening after annealing, winding insertion, and rejoining after winding insertion. Not only the magnetic properties are impaired, but also the magnetic properties are deteriorated. Therefore, it is important to treat the iron-based amorphous ribbon-made iron core under an annealing condition that can reduce embrittlement of the iron-based amorphous ribbon-made iron core and suppress deterioration of magnetic properties.

By the way, as a conventional technique for annealing an iron core made of an iron-based amorphous ribbon, for example, the technical data of Allied Signal Co., USA, and JP-A-61-40015 and JP-A-2-16706 are described. There is technology.

According to the technical data of Allied Signal Co., USA, the recommended annealing temperature is 380 ° C. for 2 hours. Further, in the above-mentioned JP-A-61-40015, it is said that the temperature is raised to 400 ° C. and kept for 30 minutes to 2 hours. In the above-mentioned Japanese Patent Laid-Open No. 2-16706, the temperature is 400 ° C.

[0005]

After all, according to the prior art, an iron core made of an iron-based amorphous ribbon is used at 380 ° C. or 400 ° C.
Is being annealed. However, as a result of research conducted by the inventors of the present invention, as shown in FIG. 2, it was found that the iron loss ratio drastically changes at the annealing temperature of 320 ° C. Therefore,
In the conventional technique of annealing at a temperature of 380 ° C. or 400 ° C., the embrittlement of the iron-based amorphous ribbon is accelerated,
There is a problem that it is easily damaged during handling in the treatment process after annealing.

On the other hand, as shown in FIG. 3, it can be seen that the fracture bending diameter of the iron-based amorphous ribbon becomes smaller as the annealing temperature lowers, so that the iron-based amorphous ribbon becomes less likely to break when the annealing temperature is lowered.

Therefore, it is necessary to determine the annealing temperature of the iron core made of the iron-based amorphous ribbon in consideration of both the improvement of fracture bending diameter, that is, the improvement of brittleness and the reduction of iron loss, that is, the improvement of magnetic properties. ..

An object of the present invention is to provide a method of manufacturing an amorphous transformer which can remarkably reduce the brittleness and the deterioration of magnetic properties due to annealing of an iron core made of an amorphous iron ribbon.

[0009]

The above object is achieved by forming an iron core of a transformer from an iron-based amorphous ribbon, annealing the iron core at a temperature of 300 to 320 ° C., and then subjecting it to the next step. It

The above-mentioned purpose is to form an iron core of a transformer by an iron-based amorphous ribbon, and to make the iron core 300 to 320 ° C.
After annealing under the temperature of, by performing the bonding work while heating the joint part of the iron core, and by heating the joint part of the iron core in a constant temperature bath, further This can be achieved even better by performing the joining work of the joining portion of the iron core while heating the iron core by the high frequency heating means.

[0011]

In the present invention, the iron-based amorphous ribbon is made to be annealed at a temperature of 300 to 320 ° C.

By the way, as described above, and as shown in FIG. 2, the iron loss is smallest near the annealing temperature of 320 ° C.
With this as a boundary, the iron loss increases even if the annealing temperature is increased or decreased. The annealing temperature at which the iron loss, which is considered to be a significant improvement in magnetic properties, can be reduced by 50% or more is about 300 to 36.
It is 0 ° C. On the other hand, as shown in FIG. 3, the annealing temperature capable of improving the fracture bending diameter, that is, improving the brittleness by 30% or more is 320 ° C. or less. Therefore, the present invention considers both the reduction of brittleness and the deterioration of magnetic properties of the iron-based amorphous ribbon, and the annealing temperature is set to 300 to 32.
The temperature is set to 0 ° C., and by treating at this annealing temperature, the brittleness can be relaxed and the magnetic properties can be significantly reduced.

Further, in the present invention, the joining work is carried out while heating the portion to be the joining portion of the iron core. In general, iron-based amorphous ribbons exhibit ductility when heated and their brittleness is improved. Therefore, the brittleness can be further improved and the damage during the joining work can be reduced by heating the portion to be the joining portion of the iron core.

Further, according to the present invention, since the portion to be the joint portion of the iron core is heated in the constant temperature bath, the thermal efficiency is good and it can be heated to the required temperature in a short time.

Furthermore, in the present invention, the iron core is heated by a high frequency heating means. Thereby, each part of the iron core can be heated uniformly, so that the variation of the fracture strength can be eliminated, and the workability of the joining part of the iron core can be further improved.

[0016]

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

FIG. 1 shows an embodiment of the method of the present invention, showing a transformer iron core using an iron-based amorphous ribbon, and FIG. 2 is an annealing temperature and iron loss of an iron-core amorphous ribbon-made iron core. And FIG. 3 is a characteristic curve diagram showing the relationship between the annealing temperature and the fracture bending diameter, and FIG. 4 is an explanatory view of a measuring instrument for measuring the fracture bending diameter.

In order to manufacture a transformer by forming an iron core from an iron-based amorphous ribbon and attaching a winding wire to the iron core, the following steps are usually performed. That is, as shown in FIG.
The iron-based amorphous ribbon 2 is wound around the iron core frame 1 and laminated to form the iron core 3. Next, annealing is performed to remove strain. After annealing, the portion to be the joint 4 is opened. Then,
Removing the iron core frame 1 and inserting another iron core frame, or using the iron core frame 1 as it is and winding (not shown in FIGS. 1 to 4)
Insert. After that, they are joined again at a portion which becomes the joint portion 4 to form a transformer.

By the way, by performing strain relief annealing,
The iron-based amorphous ribbon made of the iron core 3 becomes brittle, and breakage occurs during opening of the joint 4 after annealing, insertion of the winding wire, and re-bonding work after the insertion of the winding wire. Not only does this impair the magnetic properties, but also leads to deterioration of the magnetic properties. Therefore, it is necessary to treat the iron core 3 made of the iron-based amorphous ribbon at an annealing temperature that can suppress the embrittlement and the deterioration of the magnetic properties as much as possible.

Regarding the magnetic characteristics and the annealing temperature, the iron loss ratio shown in FIG. 2 is obtained by setting the value of the iron loss at the annealing temperature of 380 ° C. to 1.0. As you can see from this Figure 2,
The iron loss becomes the smallest near the annealing temperature of 320 ° C., and the iron loss increases with the annealing temperature increasing or decreasing at the boundary. Further, the annealing temperature capable of reducing the iron loss by 50% or more, which is expected to greatly improve the magnetic properties, is 300 to 360 ° C. as can be seen from FIG.

On the other hand, the brittleness and the annealing temperature are shown in FIG.
The fracture bending diameters shown in are those obtained by sequentially taking the fracture bending diameter ratios with the value at the annealing temperature of 380 ° C. being 1.0. As shown in FIG. 3, according to the measurement result of the fracture bending diameter with respect to the annealing temperature, the fracture bending diameter becomes smaller as the annealing temperature lowers. That is, the iron-based amorphous ribbon 2 is less likely to break. The annealing temperature is 320 ° C. or lower when the brittleness, which is considered to be greatly improved in fracture bending diameter, can be improved by 30% or more.

Therefore, from FIG. 2 and FIG. 3, the annealing temperature at which iron loss reduction and brittleness reduction can be greatly improved is 300.
It can be seen that the best temperature is 320 ° C plus or minus 5 ° C. Therefore, in this embodiment of the present invention, 300 to 320 ° C.
The iron core 3 made of the iron-based amorphous ribbon is processed at the annealing temperature of.

The above-mentioned measurement of the fracture bending diameter was carried out using the measuring instrument 10 shown in FIG. That is, when the iron-based amorphous ribbon 2 is sandwiched between the fixed plate 11 and the movable plate 12 of the measuring instrument 10 and the movable plate 12 is gradually squeezed, and the iron-based amorphous ribbon 2 is broken, the dimension 1 (L) Was defined as the fracture bending diameter.

Next, FIG. 5 is an explanatory view of an embodiment of the present invention in which a portion to be a joint portion of an iron-based amorphous ribbon is heated to perform the joining work, and FIG. 6 is an illustration of the iron-based amorphous ribbon. It is a characteristic curve figure which shows the relationship between heating temperature and a destruction rate. Iron-based metals generally exhibit ductility when heated. When the iron-based amorphous ribbon is heated, it exhibits ductility as well as the iron-based metal, as shown in FIG. 6, and the fracture rate decreases.

Therefore, in the embodiment shown in FIG. 5 of the present invention,
After opening the joint 4 of the iron core 3, the winding 6 is inserted again from the portion 5 to be the joint, and then the joining work is performed while heating from the portion 5 to be the joint by the heating means 13. The heating means 13 is configured to include a power source 14, a fan 15, and a heater 16, and sends hot air 17 to the portion 5 serving as the joining portion, and heats the hot air 17 to, for example, 100 to 150 ° C. Perform the joining work.
As a result, the brittleness of the iron core 3 made of the iron-based amorphous ribbon can be further improved, and damage during the joining work can be prevented.

FIG. 7 is a vertical cross-sectional view showing another embodiment of the heating means at the portion which becomes the joining portion of the iron core made of the iron-based amorphous ribbon. In the embodiment shown in FIG. 7, the portion 5 to be the joining portion of the iron core 3 made of the iron-based amorphous ribbon is placed in the constant temperature bath 18, and the joining work is performed while heating to 100 to 150 ° C., for example. .. As a result, in this embodiment, it is possible to prevent breakage of the portion 5 that becomes the joint portion during the joining work.
Since the thermal efficiency is good and it can be heated to the predetermined temperature in a short time, the working time can be shortened.

Next, FIG. 8 is a view showing another embodiment of the heating means at the time of the joining operation of the joining portion of the iron core made of the iron-based amorphous ribbon. The heating means 1 of the embodiment shown in FIG.
Reference numeral 9 includes a high-frequency signal transmission source 20 and a high-frequency excitation winding 21 wound around the iron-based amorphous thin ribbon iron core 3 and connected to the high-frequency signal transmission source 20. At the time of joining the parts 5 to be the parts, the whole iron core 3 is joined while heating to 100 to 150 ° C. by using high frequency. As a result, in this embodiment, since each part of the iron core 3 can be heated uniformly, it is possible to eliminate variations in the breaking strength during the joining work and further improve the joining workability.

[0028]

According to the invention described in claim 1 of the present invention described above, an iron core of a transformer is formed by an iron-based amorphous ribbon, and the iron core is annealed at a temperature of 300 to 320 ° C. Since it is subjected to the process, there is an effect that the brittleness of the iron core made of the iron-based amorphous ribbon and the deterioration of the magnetic properties can be significantly improved.

According to the second aspect of the present invention, the joining work is carried out while heating the portion to be the joining portion of the iron core made of the iron-based amorphous ribbon, so that the brittleness can be further improved. Therefore, there is an effect that damage during the joining work can be prevented.

Further, according to the third aspect of the present invention, since the portion to be the joining portion of the iron core is heated in the constant temperature bath, it is possible to prevent damage during the joining work. In addition to the above, since the thermal efficiency is good, there is an effect that the bonding work can be performed in a short time.

According to the invention of claim 4 of the present invention, while heating the iron core by the high frequency heating means,
Since the joining work of the joining portion of the iron core is performed, in addition to having an effect of preventing damage during the joining work, since each portion of the iron core can be heated uniformly, variations in breaking strength during the joining work are eliminated. Therefore, there is an effect that the workability of joining can be further improved.

[Brief description of drawings]

FIG. 1 shows an embodiment of the method of the present invention and is a diagram showing a transformer core using an iron-based amorphous ribbon.

FIG. 2 is a characteristic curve diagram showing a relationship between an annealing temperature and an iron loss of an iron-based amorphous ribbon.

FIG. 3 is a characteristic curve diagram showing a relationship between an annealing temperature and a fracture bending diameter of an iron-based amorphous ribbon.

FIG. 4 is an explanatory diagram of a measuring device that measures a fracture bending diameter.

FIG. 5 is an explanatory diagram showing an embodiment of the present invention in which a joining portion of an iron core made of an iron-based amorphous ribbon is heated by a heating means to perform joining work.

FIG. 6 is a characteristic curve diagram showing the relationship between the heating temperature and the destruction rate of an iron-based amorphous ribbon.

FIG. 7 is a vertical cross-sectional view showing another embodiment of a heating means at a portion which becomes a joint portion of an iron core made of an iron-based amorphous ribbon.

FIG. 8 is a vertical cross-sectional view showing another embodiment of a heating means at a portion which becomes a joint part of an iron core made of an iron-based amorphous ribbon.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Iron core frame, 2 ... Iron type amorphous ribbon, 3 ... Iron core made of iron type amorphous ribbon, 4 ... Joint part of iron core, 5 ... Part which becomes a joint part, 6 ... Winding, 13 ... Heating means, 14 ... power source constituting heating means, 15 ... same fan, 16 ... same heater, 17 ... hot air, 18 ... constant temperature tank as other heating means, 1
9 ... Another heating means, 20 ... High-frequency signal source that constitutes the heating means, 21 ... Same high-frequency excitation winding.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoyuki Sawaguchi 46-1, Tomioka, Nakajo-machi, Kitakanbara-gun, Niigata Prefecture Nakajo Plant, Hitachi, Ltd. (72) Inventor Kazumi Ito Kazumi 2-chome Nishitsujikeoka, Chofu-shi, Tokyo No. TEPCO Technical Research Institute (72) Inventor Shoichiro Eren 2-4-1 Nishitsutsujigaoka, Chofu-shi, Tokyo Tokyo Electric Power Co. Technical Research Institute

Claims (4)

[Claims] 1. A method for producing an amorphous transformer, which comprises forming an iron core of a transformer with an iron-based amorphous ribbon, annealing the iron core at a temperature of 300 to 320 ° C., and then subjecting it to the next step. 2. An iron-based amorphous ribbon is used to form an iron core of a transformer, the iron core is annealed at a temperature of 300 to 320 ° C., and then the joining work is performed while heating the portion to be the joining portion of the iron core. And a method for manufacturing an amorphous transformer. 3. The method for manufacturing an amorphous transformer according to claim 2, wherein a portion which becomes a joint portion of the iron core is heated in a constant temperature bath. 4. An iron-based amorphous ribbon is used to form an iron core of a transformer, the iron core is annealed at a temperature of 300 to 320 ° C., and then the iron core is heated by a high-frequency heating means to form a joint portion of the iron core. A method for manufacturing an amorphous transformer, which comprises performing a joining operation.