JPH04137515A - Manufacture of square-shaped core - Google Patents

Abstract

PURPOSE:To simplify the manufacturing process of a square-shaped core by forming the core in such a way that a central pillar formed to a square shape is used as a central magnetic leg and a side pillar is used as a side magnetic leg, and then, common pillars are used as yoke sections. CONSTITUTION:After a square-shaped member 61 which is provided with a central pillar 62, side pillar 63, and a pair of the first and second common pillars 65 and 66 which respectively connect the end sections of the pillars 62 and 63 are formed from a granulated powder 54 with a single acting press device 55, the pillars 62, 65, and 66 of the member 61 are machined with a grinder device 71. As a result, a square-shaped core 81 which uses the central pillar 62 as a central magnetic leg 82, side pillar 63 as a side magnetic leg 83, the first common pillars 65 and 66 as the first and second yoke sections 85 and 86 is manufactured. Therefore, the manufacturing process of this square- shaped core can be simplified.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for manufacturing a mouth-shaped core made of a magnetic material used for the magnetic core of choke coils, noise filters, etc. The present invention relates to a method for manufacturing a mouth-shaped core by performing molding and cutting.

(Prior Art) In recent years, there has been an increasing demand for smaller electronic devices, and in particular, there is a demand for thin and lightweight electronic devices that can be carried and used outdoors or indoors.

Therefore, there is a strong demand for choke coils, noise filters, and the like used in these electronic devices to be smaller and lighter.

Therefore, cores made of magnetic materials used as the magnetic cores of choke coils, noise filters, etc. are strongly required to be thinner and lighter, and various proposals have been made to date.

A mouth-shaped core having a mouth-shaped shape is known as a magnetic core of the choke coil, etc., and a conventional example of the mouth-shaped core will be described with reference to FIG. 6.

In FIG. 6, a mouth-shaped core 1 made of a magnetic material such as ferrite faces a central magnetic leg 2 having a substantially square cross section, has a hole 7, and has side magnetic legs 3 arranged in parallel.
One end of each of the center magnetic leg 2 and the side magnetic legs 3 is connected by a first yoke part 5 and a second yoke part 6, respectively.

At this time, the top and bottom views of the mouth mold core 1 form a mouth mold formed from each of the magnetic legs, and the top and bottom surfaces of the mouth mold are each formed on a plane.

To construct a choke coil or the like using the mouth-shaped core 1, a coil bobbin 9 is fitted onto the central magnetic leg 2 of the mouth-shaped core 1, and the body of the coil bobbin 9 is rotated to wind an enameled wire or the like. It is designed to rotate.

When the coil bobbin 9 is fitted into the mouth-shaped core l as described above, the upper and lower parts of the winding of the coil bobbin 9 are
Since it protrudes by two widths from the mouth surface of the mouth-shaped core 1, the space around the protrusion is not effectively utilized, and when the transformer or the like is mounted on an electronic circuit board or the like (not shown), There were problems such as the protrusion becoming an obstacle.

Here, a conventional example of a mouth-shaped core whose structural design makes effective use of the dimensions of each part will be described with reference to FIG.

The mouth-shaped core 11 has a central magnetic leg 12 having a substantially square cross section.
Side magnetic legs 13 are arranged parallel to each other and have holes 17, and one end of each of the center magnetic leg 12 and the side magnetic legs 13 is connected to the first yoke part 15 and the second yoke part 16, respectively. It is constructed by being connected.

At this time, since the central magnetic leg 12 of the mouth-shaped core 11 is configured to connect the lower parts of the first yoke part 15 and the second yoke part 16, the upper surface of the central magnetic leg 12 and the lower part of the second yoke part 16 are connected to each other. 1st
A space is provided between the upper surface of the yoke portion 15 or the second yaw portion 16.

In other words, when the coil bobbin 19 is fitted onto the central magnetic leg 12 and an enameled wire or the like is wound, the upper part of the winding of the coil bobbin 19 is prevented from protruding by the height of the space. .

Next, FIG. 8(a) shows a manufacturing method for manufacturing the mouth-shaped core 1 using a dry single-acting press device 25.
This will be explained with reference to (b).

FIG. 8(a) is a plan view showing a state in which the lower mold 23 is fitted into the formwork 21 of the single-acting press device 25, and FIG.
), the granulated powder 24 made of a magnetic material filled in the mouth molding hole 21a of the mold frame 21 is inserted into the upper mold 22 and the lower mold 23.
FIG. 3 is a cross-sectional view taken along line AA, showing a state in which pressure is applied.

The lower mold 23 is inserted into the mouth molding hole 21a formed in the mold frame 21 from below, and the mouth molding hole 21a is filled with granulated powder 24 made of a magnetic material, and the upper mold 2 is inserted from above.
2 is inserted and pressurized, and the mouth-shaped core 1 is molded.

At this time, the pressure surface of the upper mold 22 and the pressure surface of the lower mold 23 are
In order to uniformly pressurize the granulated powder 24, each of the granulated powders 24 is formed on a flat surface, so that the upper and lower mouth surfaces formed by the magnetic legs of the mouth mold core 1 to be molded are each formed on a flat surface. Ru.

According to the above-mentioned single-acting type brace device 25, the mouth-type core 1 is pressure-molded with uniform hardness in each part, and the single-acting type press device 25 is small and has a simple configuration. It has the characteristics of fast molding speed and suitable for mass production.

In addition, when iron powder is applied to the magnetic material, a powder magnetic core is formed by pressure molding, and when ferrite powder is applied, a binder is added to the ferrite powder and granulated, A ferrite core is formed by pressure molding and further configuring.

Next, the double-acting brace device 35 causes the mouth-shaped core 11 to
A manufacturing method for manufacturing will be described with reference to FIGS. 9(a) and 9(b).

FIG. 9(a) is a plan view showing a state in which the lower mold 33 is fitted into the formwork 31 of the double-acting brace device 35, and FIG.
), the granulated powder 34 made of a magnetic material filled in the mouth molding hole 31a of the mold frame 31 is inserted into the upper mold 32 and the lower mold 33.
It is a BB sectional view showing a state where it is pressurized.

The lower mold 33 is inserted from below into the mouth molding hole 3]a formed in the mold frame 31, and the granulated powder 34 made of a magnetic material is filled into the mouth molding hole 31a, and the upper mold is inserted from above. 3
2 and applying a force C, the mouth-shaped core 11
to be molded.

At this time, the double-acting press device 35 is arranged such that the first lower mold pressing surface 33a of the lower mold 33 faces the first upper mold pressing surface 32a of the upper mold 32, and the second lower mold pressing surface 32b faces the second lower mold pressing surface 32b. The second lower mold pressurizing surface 33b is configured to operate in double motion, and as a result, the central magnetic leg 12 is moved to the first yoke w.
A mouth-shaped core 11 connecting the lower part of the X15 and the second yoke part 16 from approximately the center is pressure molded.

According to the above-mentioned double-acting press device 35, the opposing pressure surfaces double-act with respect to the other pressure surfaces, and the granulated powder 34
Because of the pressure applied to the granulated powder 34, it is difficult to mold the granulated powder 34 to have a uniform density, and there is a risk that microcracks or the like may occur in the mouth-shaped core 11.

Furthermore, the double-acting press device 35 is large in size, has complicated operation control, and has a slow molding speed, making it unsuitable for mass production.

(Problems to be Solved by the Invention) However, according to the above-mentioned method for manufacturing a mouth mold core in which the mouth mold core is manufactured by molding using the conventional single-acting press device, the upper and lower mouth mold surfaces are each on a plane. Therefore, when a coil bobbin is fitted to the central magnetic leg of the mouth-shaped core, the upper and lower portions of the winding of the coil bobbin protrude from the mouth-shaped surface, and the coil etc. made of the mouth-shaped core etc. There is a problem in that the coil and the like are placed higher than other electronic components, and the protrusion becomes an obstacle, making it impossible to stably mount the coil and the like on an electronic circuit board and the like.

Further, according to the method for manufacturing a mouth-shaped core in which the mouth-shaped core is manufactured by molding with a double-acting type brace device, although the coil bobbin fitted to the center magnetic leg is efficiently accommodated, the double-acting type Because a brace device is used, it is difficult to mold the magnetic material to a uniform density, and when double-acting braces are used, there is a risk that internal stress will be applied to the mouth-shaped core and micro-cracks will occur. There was a problem called divination.

Furthermore, when pressurized press molding is attempted using the double-acting press device in manufacturing the mouth-shaped core, the double-acting press device itself is large, operation control is complicated, and the molding speed is slow. Since it is slow and unsuitable for mass production, it has the problem of increasing production costs.

The present invention has been made in view of the above circumstances, and provides a mouth mold with a structural design that effectively utilizes the dimensions of each part through a simple manufacturing process without using a molding device that is difficult and complicated to control. The present invention provides a method for manufacturing a mouth-shaped core that can manufacture the core while preventing the occurrence of microcracks and the like.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a central magnetic leg,
A method for manufacturing a mouth-shaped core having a side magnetic leg disposed parallel to the center magnetic leg, and a pair of yoke portions connecting one end of each of the center magnetic leg and the side magnetic leg, the center column; After molding a magnetic material into a mouth shape having a side pillar and a pair of common pillars that connect one end of each of the center pillar and the side pillars, cutting the mouth mold surface of the molded body. The mouth-shaped surface is divided into a plurality of parts, thereby forming a central magnetic leg on the center column molded into the mouth-shaped shape, a side magnetic leg on the side columns, and further forming two common columns with a yoke part. By doing so, the above objectives are achieved.

(Function) In the present invention, the magnetic material is
A magnetic material is molded into a mouth shape having a central pillar, side pillars, and a pair of common pillars that connect one end of each of the central pillar and the side pillars, and a plurality of mouth mold surfaces of the molded body are formed. By cutting the center column into two parts, a center magnetic leg is formed on the square-shaped center column, and a side magnetic leg is formed on the side columns. magnetic legs and
It is possible to manufacture a mouth-shaped core having legs 11+11a arranged parallel to the central magnetic leg, and a pair of yoke parts connecting one end of each of the central magnetic leg and the side magnetic legs.

In addition, the mouth-shaped core is manufactured by molding magnetic material into a mouth shape using a small and simple device such as a single-acting press, and cutting the mouth shape. There is no need to use large and complicated devices such as dynamic braces.

In addition, in the single-acting press device used in manufacturing the mouth-shaped core, the pressing surface is single-acting and the pressing surface is flat, so that the magnetic material is applied with uniform density. Since it is pressure molded, it is possible to prevent microcracks from occurring due to internal stress during pressure molding.

Furthermore, 1. Since the mouth-shaped core produced by the above manufacturing method is cut so as to divide the mouth surface of the mouth-shaped molded body into a plurality of parts, the coil bobbin fitted into the central magnetic leg of the mouth-shaped core is It is possible to prevent the winding portion from protruding by an amount equal to the height of the center magnetic leg subtracted from the height of the side magnetic legs and the yoke portion, and therefore the coil etc. formed by the mouth-shaped core etc. The height can be reduced by the amount of deterrence.

Further, the mouth-shaped core is cut so as to divide the mouth-shaped surface of the mouth-molded body into a plurality of parts, and the magnetic material is removed in the cut portions, so that the mouth-shaped core is cut by the amount of the cut portion. It is possible to reduce the size of the coil etc. made up of the above.

(Example) Embodiments of the present invention will be described in detail based on the drawings.

FIG. 1(a) is a perspective view showing a molding process according to the method for producing a mouth-shaped core of the present invention, and FIG. 1(b) is a perspective view showing a mouth-molded member molded by the molding process according to the same embodiment. figure,
FIG. 1(c) is a perspective view showing the cutting process according to the same embodiment, FIG. 1(d) is a perspective view showing the square core I formed by the manufacturing method according to the same embodiment, and FIG. ) is a plan view showing a mouth-shaped core manufactured by the manufacturing method according to the same example, and FIG. 2(b) is a cross section showing the XX cross section of the mouth-shaped core manufactured by the manufacturing method according to the same example 3 is a perspective view showing another mouth-shaped core formed by the manufacturing method according to the present invention, FIG. 4 is a perspective view showing another mouth-shaped core formed by the manufacturing method according to the invention, FIG. 5(a) is a perspective view showing a mouth-shaped core formed by another manufacturing method according to the present invention, and FIG. 5(b) is a perspective view of the mouth-shaped core manufactured by a manufacturing method according to the same embodiment. A cross-sectional view showing the -Y cross section is shown.

As shown in FIG. 1(a), approximately in the center of the formwork 51,
A rectangular rectangular hole 51c is formed by molding or the like, and a columnar mold 51b is provided inside the rectangular hole 51c, thereby forming a mouth mold hole 51a. 51a is female type.

From below the mouth mold hole 51a of the mold 51, the mouth mold hole 51
A lower mold 53 having the same shape as a is used as a male mold, and its upper part is inserted as shown by arrow 1 in the figure.

The mouth hole 51a is filled with granulated powder 54 made of a magnetic material.

From above the mouth mold hole 51a filled with the granulated powder 54, a hill mold 52 having the same shape as the hole 5+a and the lower mold 53 is inserted into the hole 5+a and the lower part as shown by the arrow [in the figure]. is inserted.

Therefore, the single-acting breath device 55 configured as described above
The granulated powder 54 filled in the mouth hole 51a of the upper mold 5
2 upper mold pressure surface 52a and lower mold pressure surface 53a of the lower mold 53
The opening molding member 6 shown in FIG. 1(b) is pressurized by
It is molded into 1.

The mouth-shaped molded member 61 faces a wide central pillar 62 in the front, has a hole 67, has a side pillar 63 arranged in parallel at the rear, and has a central pillar 62M! and the end portions of the side columns 63 are connected by a pair of first common columns 65 and second common columns 66, respectively.

Moreover, the mouth molding member 61 has upper and lower mouth mold surfaces molded by each company because the upper mold pressure surface 52a of the upper mold 52 and the lower mold pressure surface 53a of the lower mold 53 have a planar shape. are each formed on a plane.

Next, as shown in FIG. 1(c), a grinder device 71 in which a disc-shaped grinder 72 made of an abrasive material or the like is pivotally supported on a rotating shaft 73 is driven by a drive device (not shown). is rotatably driven in the direction of the arrow ■ in the figure, and the mouth molding member 61 is moved in the direction of the arrow in the figure by a moving mechanism (not shown).

Therefore, the center column 62, the first common column 65, and the second common column 66 of the mouth molded member 61 are cut along the longitudinal direction of the center column 62 by the grinder device 71.

At this time, the cutting width by the above-mentioned cutting process is
The cutting depth is determined by the installation height of the rotary shaft 73 on which the disc-shaped grinder 72 is supported, and the cutting width and cutting depth can be changed freely. It has become.

By performing the cutting process, a mouth mold core 81 is formed from the mouth mold molding member 61, as shown in FIG. 1 (dl).

The mouth-shaped core 81 has a central magnetic leg 82 on the front side and a side magnetic leg 83 on the rear side arranged in parallel, and each end of the central magnetic leg 82 and the side magnetic leg 83 has a pair of first yoke parts 85 and Second
They are configured by being connected to each other by a yoke portion 86.

At this time, by the cutting process, cutting parts 80 are formed in the center magnetic leg 82, the first yoke part 85, and the second yoke part 86, and the center column 62 of the mouth molding member 61 is 82, the side pillar 63 becomes a side magnetic leg 83, and the first common pillar 65 and second common pillar 66 become a first yoke part 85 and a second yoke part 86, respectively.

As is clear from FIG. 2(a), the mouth-shaped core 81 has a mouth shape formed from each magnetic leg when viewed from above and from below.

Moreover, as shown in FIG. 2(b), the mouth-shaped core 81 is
Since it is formed by cutting the mouth molded member 61, the central magnetic leg 82...11magnetic1!1183
The height H1 of the central magnetic leg 82 is subtracted from the height H2 of the central magnetic leg 82.

The mouth-shaped core 81 formed as described above is shown in FIG. 2(b).
As shown in , a coil bobbin 89 is fitted onto the central magnetic leg 82, and by rotating the main body of the coil bobbin 89, an enameled wire or the like is wound to form a coil or the like. .

According to the method for manufacturing the mouth-shaped core 81 described above, the single-acting press device 55 applies the granulated powder 54 to the center column 62 and the side columns 6.
3, and molded into a pair of first common members 61 that connect the respective ends of the central pillar 62 and the side pillars 63, and then, the central pillar 62 of the mouth-shaped molded member 61 and the first common molded member 61 are molded. By cutting the pillar 65 and the second common pillar 66 with a grinder device 71, the central pillar 62 is formed into a central magnetic leg 82,
The side pillar 63 is connected to the side magnetic leg 83, and the first common pillar 65 and second common pillar 66 are connected to the first yoke part 85 and the second yoke part 8, respectively.
6, the mouth-shaped core 81 can be manufactured.

That is, the method for manufacturing the mouth-shaped core 81 is to process the granulated powder 54 using a small and simple device such as a single-acting press device 55.
After molding into the mouth molding member 61, the mouth molding member 6
By cutting 1 with the grinder device 71, the mouth-shaped core 81 is formed! 81, there is no need to use a large and complicated device such as a double-acting press, and therefore the granulated powder 54 can be pressure-molded with uniform density and the molding speed can be improved. , mass production becomes possible, and microcracks caused by internal stress during pressure molding can be prevented.

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After being molded into the 1-type molded member 61, the center column 62, the first common column 65 are processed by the grinder device 71.
Since the second common column 66 is machined, the coil bobbin 89 fitted to the central magnetic leg 82 of the mouth-shaped core 81
The winding portion of
It is possible to prevent the coil from protruding by the amount by subtracting l, so that the height of the coil formed by the mouth-shaped core 81 and the like can be made low.

In addition, the mouth-shaped core 81 produced by the manufacturing method is cut by the grinder device 71, so that the granulated powder 54 that has been press-molded in the cutting part is removed. 81, and thus the mouth-shaped core 8
It is possible to reduce the weight of the coil etc. made up of the 1st grade.

Furthermore, in the mouth-shaped core 81 manufactured by the manufacturing method, the height Hl of the center magnetic leg 82 is formed to be lower than the height H2 of the side magnetic legs 83, etc., so that the coil bobbin 89 is Center 1iff#j! When fitted into J82, the winding width of one side of the coil bobbin 89 is equal to that of the side magnetic leg 83.
Therefore, when a coil etc. constituted by the mouth-shaped core 81 etc. is mounted on an electronic circuit board etc., the side magnetic legs 83 etc. can be prevented from protruding beyond the height H2 of the board. By doing so, the coil etc. can be stably mounted.

In the above manufacturing method, if the disc part of the disc type grinder 72 of the grinder device 71 is subjected to a tapering process, as shown in FIG. 97 and the second tapered portion 9 to the second yoke portion 86.
8 can be manufactured.

Furthermore, in the manufacturing method, the disc type grinder 7
By applying curved surface processing to the ridge part 2, as shown in FIG. 101 can be manufactured.

Next, other embodiments according to the present invention are shown in FIGS. 5(a) and 5(b).
This will be explained with reference to.

As in the previous embodiment, the granulated powder 54 is molded into a mouth-molded member using a single-action press device 55, and a central column and a pair of common pillars are formed on both mouth surfaces of the mouth-molded member. By cutting with a grinder device, the center column is made into the center magnetic leg 112, the side columns are made into the side magnetic legs 113, and the first common column and the second common column are made into the first yoke part 115 and the second yoke part 116, respectively. Thus, the mouth-shaped core 111 shown in FIG. 5(a) is manufactured.

At this time, a first cutting part 121 is formed on the upper surface and a second cutting part 122 is formed on the lower surface of both of the mouth surfaces of the mouth-shaped core [1]. Therefore, the height of the center M1 leg 112 is formed to be lower than the height of the first yoke portion 115 and the like.

That is, as shown in FIG. 5(b), one side of the coil bobbin 19 fitted to the center magnetic leg 112 of the mouth-shaped core 111 is connected to the side magnetic leg 113. Note that the first cutting part 121 and the second cutting part 121 and the second
The process of cutting the cutting part 122 may be manufactured in a single process using a grinder device equipped with two disk-type grinders, or may be divided into multiple processes.

Furthermore, the method for manufacturing the mouth-shaped core according to this embodiment can also produce the same effects as in the previous embodiment.

Note 5: When iron powder is used as the magnetic material, a powder M1 core is not formed by pressure molding, and when ferrite powder is used, a binder is added to the ferrite powder, granulated, and then pressed. A ferrite core is formed by pressure molding and further firing.

In addition, in this example, in order to pressurize the granulated powder,
Although a single-acting press machine is used, the present invention is not limited to this, and for example, a wet extrusion molding machine or the like may be used.

Furthermore, in this embodiment, the cutting process is not limited to the number of times; for example, a rotary belt type sander or the like may be used.

(Effects of the Invention) Since the method for manufacturing a mouth-shaped core according to the present invention is configured as described above, it has the following effects.

(1) Using a single-acting press or the like, the magnetic material is shaped into a mouth shape that includes a center column, a side column, and a pair of common columns that connect one end of each of the center column and side columns. By molding and cutting the mouth mold surface of the molded body into a plurality of parts, the inside of the molded body is molded into a mouth mold shape.
A leg is formed at the center of the L-column, and an Ill Ia leg is formed on the side column, and the common column is used as a yoke part, and a central magnetic leg and a side magnetic leg arranged parallel to the middle 7LL-magnetic leg are formed. Since it is possible to manufacture a mouth-shaped core having a pair of yoke portions that connect one end of each of the central magnetic leg and the side magnetic legs, a complicated manufacturing process is not required, and the manufacturing process is therefore simplified. It has the excellent effect of being able to

(2) In addition, the mouth-shaped core is formed so that the coil bobbin can be efficiently accommodated and can be mounted on an electronic circuit board, etc., without having to be molded using a large double-acting press device with complicated operation control. , the magnetic material is molded into a mouth molding member using a linear motion type press machine and then cut to produce the mouth mold core, so the magnetic material is pressure molded with a uniform density, and the molding It has excellent effects in that speed is improved, mass production is possible, and furthermore, generation of microcracks etc. due to pressurization by a double-acting press device can be prevented, and quality can be improved.

(3) Furthermore, since the mouth-shaped core produced by the above manufacturing method is cut so as to divide the mouth surface of the mouth-molded body into a plurality of parts, the mouth-shaped core is not fitted into the central magnetic leg of the mouth-shaped core. The winding part of the coil bobbin is set from the height of the side magnetic leg and yoke part,
It is possible to suppress the protrusion by an amount equal to the height of the central magnetic leg, thereby making it possible to reduce the height of the coil etc. formed by the mouth-shaped core etc., which in turn makes it possible to reduce the height of the coil etc., thereby improving the electronic device in which the coil etc. is built-in. What it does have is that it can be made smaller and thinner.

(4) In addition, the mouth core is cut by cutting the mouth surface of the mouth molded body into a plurality of parts, so that the magnetic material is removed at the cutting portion, so that the magnetic material is removed by the cut portion. This has the excellent effect of being able to reduce the weight of a coil or the like constituted by a mouth-shaped core or the like.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view showing a molding process according to the method for manufacturing a mouth-shaped core of the present invention, and FIG. 1(b) is a perspective view showing a mouth-molded member molded by the molding process according to the same embodiment. Figure 1 (c) is a perspective view showing the cutting process according to the same example, Figure 1 (d) is a perspective view showing the mouth-shaped core 1 formed by the manufacturing method according to the same example, and Figure 2 ( a) is a plan view showing a mouth-shaped core manufactured by the manufacturing method according to the same example; FIG. 3 is a perspective view showing another mouth-shaped core formed by the manufacturing method according to the present invention. FIG. 4 is a perspective view showing another mouth-shaped core formed by the manufacturing method according to the invention. FIG. 5(a) is a perspective view showing a mouth-shaped core formed by another manufacturing method according to the present invention, and FIG. 5(b) is a perspective view of the mouth-shaped core manufactured by a manufacturing method according to the same embodiment. FIGS. 6 and 7 are a cross-sectional view showing a Y cross section; FIGS. 6 and 7 are perspective views showing a conventional mouth-shaped core; FIG. Figure 8 (b) is a cross-sectional view showing the A-A cross section of the single-acting press, Figure 9 (al is an explanatory diagram illustrating the method of manufacturing a mouth-shaped core using a conventional double-acting press, Figure 9 (b) ) is a sectional view showing the B-B cross section of the double-acting type brace. 51 ・ 53 ・ 55 ・ 61 ・ 71 ・ 72 ・ 81 ・ 83 ・ 85 ・ 86 ・ ・Formwork, 52 . . . Upper mold, lower mold Mold, 54... Granulated powder/single-acting press device, - Mouth molding member, - Grinder equipment! - Disc type grinder/mouth core, 82... - Side magnetic leg, - First yoke part,・Second yoke part. ・Central magnetic leg

Claims (1)

[Claims] (1) A square core having a central magnetic leg, side magnetic legs arranged parallel to the central magnetic leg, and a pair of yoke portions connecting one end of each of the central magnetic leg and the side magnetic leg. In the manufacturing method, a magnetic material is molded into a rectangular shape having a center column, a side column, and a pair of common columns connecting one end of each of the center column and the side columns, and then the molded body is By cutting the square-shaped surface, the square-shaped surface is divided into a plurality of parts, thereby forming a center magnetic leg on the square-shaped center column and side magnetic legs on the side columns. . A method for manufacturing a square core, further comprising manufacturing a square core in which the common column is a yoke portion.