JPH01175212A - Ring-shaped dust core, its manufacture and its manufacturing apparatus - Google Patents

Abstract

PURPOSE:To obtain a magnetic characteristic which is several times better as compared with a conventional product by a method wherein, after an easy axis of magnetization of crystals of an anisotropic ferromagnetic powder has been lined up in the circumferential direction, the powder is pressed and solidified to form a ring shape by using a binder to be mixed. CONSTITUTION:A ring-shaped groove 3 used to contain a ferromagnetic powder 2 of magnetic anisotropy is formed in the surface top of a female mold 1; a conductive wire 4 made of silver is arranged in the center in such a way that it is pierced from the upper part to the lower part. A sweep generator 6 of an ultrasonic vibration apparatus 5 generates ultrasonic waves at a vibrator 7, vibrates the female mold 1 and puts the contained ferromagnetic powder to a floating state. A male mold 8 is equipped, at its under surface, with a ring-shaped protruding part 9 which can be mated with the ring-shaped groove 3 in the female mold 1; when this male mold 8 is lowered, an electricity-supply terminal 11 comes into contact with a terminal 10, made of silver, which protrudes in the center; a strong electric current from a Sendai tron 12 is applied for an instant. A line of magnetic force is induced from the conductive wire 4; an easy axis of magnetization of individual crystals of the ferromagnetic powder 2 inside the ring-shaped groove 3 is lined up easily in the circumferential direction because the ferromagnetic powder is in the floating state. Then, the male mold 8 is lowered; the powder is pressed and solidified together with a binder to be mixed; a ring-shaped dust core can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a ring-shaped dust core that is an electrical component and serves as a magnetic path.

Conventional technology Traditionally, silicon steel sheets have been used as magnetic materials for heavy-duty electrical equipment such as large transformers, generators, and electric motors.When particularly high performance is required, silicon steel sheets are processed through intense cold rolling and recrystallization treatments. A grain-oriented silicon steel plate whose crystals have the same direction of easy magnetization is used. In addition, iron, nickel alloys (Hermalloy), iron-aluminum alloys (Alperm), etc. are used for small transformers, reactors, magnetic shields, etc. for low-power applications where characteristics are important. Furthermore, for high-wave applications, oxide magnetic materials (ferrite, etc.) and dust magnetic cores are used.

Problems to be Solved by the Invention In the prior art, magnetic materials have been improved according to the characteristics of electrical equipment, but the present invention has been devised to provide even better performance.

A workaround to solve the problem■ The feature is that anisotropic ferromagnetic powder such as Sendust (trade name) is pressed and solidified into a ring shape with a binder mixed in after aligning the axis of easy magnetization of the crystal in the circumferential direction. A ring-shaped dust core, ■ An anisotropic ferromagnetic powder such as Sendust (trade name) is housed in an annular groove provided in the female mold, and an ultrasonic vibration device connected to this female mold is activated to generate a Ferromagnetic powder is suspended, and a strong current is momentarily passed through a conductor that passes vertically through the center of the annular groove using a Sendai Tron or equivalent DC power supply, and the ferromagnetic powder is suspended so that the axis of easy magnetization of each crystal is in the circumferential direction. A method for manufacturing a ring-shaped dust core in which the ferromagnetic powder is aligned and then compressed with a male mold that is inserted into an annular groove, and solidified into a ring shape by a mixed binder. It has a female mold and a protrusion that fits into the annular groove of this female mold.
A male mold is press-fitted into the female mold from above, compresses the ferromagnetic powder, and solidifies together with the binder mixed in a ring shape. An ultrasonic vibration device that suspends magnetic powder, a conductor that passes vertically through the center of the female annular groove and induces lines of magnetic force when electricity is applied inside the annular groove, and a strong current that is momentarily applied to the conductor prior to pressing. This is a ring-shaped dust core manufacturing device that is supplied with a Sendai Tron or an equivalent DC power supply.

Function: The ring-shaped dust core of this invention is made by passing a strong current momentarily to align the axis of easy magnetization of each crystal in the circumferential direction before compacting into a ring shape. This dramatically increases the performance of other magnetic materials.

EXAMPLE Below, the method and apparatus for manufacturing a ring-shaped dust core of the present invention will be explained. Reference numeral 1 is a female mold, and a magnetically anisotropic ferromagnetic powder 2 such as Sendust (trade name) is accommodated on the upper surface of the female mold. It has an annular groove 3, and a silver conductive wire 4 is disposed in the center of the annular groove 3, passing through it vertically.

5 is an ultrasonic vibration device, and an ultrasonic sweep generator 6
The sweep generator 6 generates ultrasonic waves of 10 to 30 KC in the vibrator 7 to vibrate the female mold 1.

Then, the ferromagnetic powder 2 accommodated in the annular groove 3 is brought into a floating state.

8 is a male mold, and has an annular protrusion 9 on its lower surface that fits into the annular groove 3 of the female mold 1. When the male mold 8 descends, the power supply terminal 11 contacts the silver terminal 10 protruding from the center of the female mold 1, and a strong current from the Sendai Tron 12 is momentarily applied. Therefore, a conductive wire 4 passing vertically through the center of the female annular groove 3
From there, magnetic lines of force are induced according to Ampere's right-handed screw rule, and the ferromagnetic powder 3 in the annular groove 3 flows according to the lines of magnetic force.
Since the crystals are in a floating state as described above, the axes of easy magnetization of their respective crystals can be easily aligned in the circumferential direction. Then, the male mold 8 descends and presses the anisotropic ferromagnetic powder, which is aligned in the same direction and solidified together with the mixed binder, thereby producing the ring-shaped dust core 13.

The ultrasonic vibration device makes the entire powder floating regardless of its size by sweeping the generation and imaging,
Make it easier to align the axes of easy magnetization in the same direction. DC power supplies that flow strong currents are not limited to Sendai Tron.
You can replace it with something else as long as it has the same performance.

The ring-shaped dust core of the present invention, which has been manufactured through the effects of the invention, has characteristics that are several times better than conventional products of this kind. Therefore, the industrial effects of the electrical component of this invention are immeasurable.

[Brief explanation of the drawing]

The drawings are a schematic side view of the method and apparatus for manufacturing a ring-shaped dust core according to the present invention, and FIG. 2 is an external perspective view of the ring-shaped dust core. DESCRIPTION OF SYMBOLS 1... Female mold, 2... Anisotropic ferromagnetic powder, 3... Annular groove, 4... Conductive wire, 5... Ultrasonic vibration device, 8...
・Male type, 9...Annular protrusion, 12...Sendai tron,
13...Ring-shaped dust core. Applicant: Beam Electronics Industry Co., Ltd.

Claims (4)

[Claims] (1) A ring-shaped dust core made of anisotropic ferromagnetic powder such as Sendust (trade name), which is press-solidified into a ring shape with a binder mixed in after aligning the easy magnetization axes of its crystals in the circumferential direction. (2) Sendust (product name) in the annular groove provided in the female mold
An ultrasonic vibration device connected to this female mold is activated to suspend the ferromagnetic powder contained in the annular groove, and the Sendai Tron is placed in the conductor that passes vertically through the center of the annular groove. Or, by momentarily passing a strong current using an equivalent DC power supply,
A ring-shaped dust core is created by arranging the axes of easy magnetization of each crystal of ferromagnetic powder in the circumferential direction, then compressing the ferromagnetic powder with a male mold that fits into an annular groove, and solidifying it into a ring shape with a binder mixed in. Manufacturing method. (3) A female mold having an annular groove on the upper surface that accommodates the anisotropic ferromagnetic powder in an annular shape, and a protrusion that fits into the annular groove of the female mold, and is press-fitted into the female mold from above to compress the ferromagnetic powder, a male mold that solidifies together with a binder mixed in a ring shape; an ultrasonic vibrator connected to the female mold to apply vibration to suspend the ferromagnetic powder contained in the annular groove of the female mold; A ring consisting of a conductor that passes vertically through the center of the groove and induces lines of magnetic force when energized in the annular groove, and a Sendai Tron or equivalent DC power supply device that instantaneously supplies a strong current to the conductor prior to pressing. Equipment for manufacturing dust cores. (4) The upper end of the conductor is made of silver or an equivalent metal, and contacts the terminal of the male mold before or during its descent, and instantaneously supplies a strong current just before pressing. 3. The ring-shaped dust core manufacturing device according to item 3.