JPH0473912A - Manufacture of e-shaped core - Google Patents

Abstract

PURPOSE:To enable manufacture of E-type cores of structure design that each part dimension is effectively utilized by a simple fabrication process without use of any molding equipment hard to control and troublesome to handle by molding a magnetic material into a squared-eight-shape for cutting word of one squared-eight-shape face into a plurality and by cutting side columns and center common columns. CONSTITUTION:In a manufacture of an E-shaped core 81 having a center magnetic leg 82, a pair of side magnetic legs 83, 84 counterposed to sandwich the center magnetic leg 82, and a yoke 85 which couples one end of the center magnetic leg 82 with one end of each of the side magnetic legs 83, 84, a magnetic material is molded into a squared-eight-shape having a pair of said columns 62, 63, a pair of common columns 64, 65 which couple both ends of each of the side columns 62, 63, and a center common column 66 which couples the center of the side columns 62, 63, and is subjected to cutting work so that one squared-eight-shape face of the molded body 61 may be divided into a plurality; thereby, a center magnetic leg 82 is formed in the common columns 64, 65 and the center common column 66, and the side columns 62, 63 are used as the side magnetic legs 83, 84. Further, the side columns 62, 63 and the center common column 66 are cut to manufacture an E-shaped core 81.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for manufacturing an E-type core made of a magnetic material used for magnetic cores of transformers, choke coils, noise filters, etc. The present invention relates to a method for manufacturing an E-type core by performing simple 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 smaller and lighter transformers, choke coils, noise filters, and the like used in these electronic devices.

Therefore, there is a strong demand for thinner and lighter cores made of magnetic materials used as magnetic cores in transformers, choke coils, noise filters, etc., and various proposals have been made to date. .

An E-type core is generally used as a magnetic core incorporated in the transformer, etc., and a conventional example of the E-type core will be described with reference to FIGS. 5A and 5B.

In FIG. 5(a), an E-shaped core 1a made of a magnetic material such as ferrite has a central magnetic leg 2 having a substantially square cross section.
A pair of first side magnetic legs 3a and second side magnetic legs 4a are arranged on both sides of a, each having a first groove 6a and a second groove 7b. One end of each of the leg 3a and the second side magnetic leg 4a is connected by a yoke portion 5a.

At this time, the other end surfaces of the central magnetic leg 2a, the first side magnetic leg 3a, and the second side magnetic leg 4a are formed on the same plane, and
In order to optimize the magnetic properties of the E-shaped core 1a, the cross-sectional area of the central magnetic leg 2a is made equal to the sum of the cross-sectional areas of the first side magnetic leg 3a and the second side magnetic leg 4a. It is formed.

When incorporating the E-type core 1a into a transformer etc., the fifth
As shown by the imaginary line in Figure (a), a coil bobbin 8a made of a coil or the like wound with enameled wire or the like is fitted into the central magnetic leg 2a, and then assembled with an E-shaped or I-shaped core. In total, they are fixed by one fixing fitting (not shown) or the like.

As described above, the coil bobbin 8 is attached to the E-type core la.
When the coil bobbin 8a is fitted, the upper and lower parts of the winding of the coil bobbin 8a protrude from the upper and lower surfaces of the central magnetic leg 2a of the E-type core 1a by a width Za. It was not used effectively, and there were problems such as poor stability when mounting the transformer etc. on an electronic circuit board etc.

Further, as shown in FIG. 5(b), the E-type core 1b has a first groove 6b and a second groove 7b on both sides of the central magnetic leg 2b having a longitudinally rectangular cross section. A first side magnetic leg 3b and a second side magnetic leg 4b are arranged, and one end of each of the central magnetic leg 2b, first side magnetic leg 3b, and second side magnetic leg 4b is connected by a yoke portion 5b. It is made up of.

According to the E-type core lb, the width and thickness of the central magnetic leg 2b, the first side magnetic leg 3b, and the second side magnetic leg 4b are made thinner, so that the width and thickness of the transformer, etc. in which the E-type core ib is incorporated is reduced. However, like the E-type core 1a, when the coil bobbin 8b indicated by the imaginary line is fitted into the central magnetic leg 2b, the upper and lower windings of the coil bobbin 8b are 25 degrees thinner than the upper and lower surfaces of the central magnetic leg 2b. The width protrudes, making it impossible to make the transformer etc. low in profile.

Here, while satisfying the condition that the cross-sectional area of the central magnetic leg is equal to the sum of the cross-sectional areas of the first side magnetic leg and the second side magnetic leg, a structural design is performed that effectively utilizes the dimensions of each part of the E-shaped core. A conventional example in which a transformer or the like in which the E-type core is incorporated will be described with reference to FIG. 6.

In the E-type core 11, a central magnetic leg 12 elongated in the horizontal direction extends from a substantially central portion of the front surface of the yoke portion 15, and
A first side magnetic leg 13 and a second side magnetic leg 14 are disposed with a first groove 16 and a second groove 17 on both sides of the central magnetic leg 12, and the first side magnetic leg 13 and the second side magnetic leg 14 have a first groove 16 and a second groove 17. One end of each of the magnetic legs 14 is connected by the yoke portion 15, and the central magnetic leg 12,
The other end surfaces of the first side magnetic leg 13 and the second side magnetic leg 14 are formed on the same surface.

As shown by the imaginary line in FIG. 6, a coil bobbin 18 wound with enameled wire or the like to form a coil is fitted into the central magnetic leg 12 of the E-shaped core 11. By combining it with an E-type or I-type core having the same structure, a transformer or the like is formed.

According to the E-shaped core 11, the central magnetic leg 12 is elongated in the lateral direction, and has a height larger than that of the first side magnetic leg 13, the second side magnetic leg 14, and the yoke part 15. Central magnetic leg 1
By having a space above and below 2, the central magnetic leg 12
Since the coil pobbin 18 fitted in the coil pobbin 18 does not protrude beyond the inner walls of the first side magnetic leg 13, the second side magnetic leg 14, and the yoke portion 15, the structure corresponds to miniaturization of the E-type core 11. The design has been made.

Next, a manufacturing method for manufacturing the E-shaped core 1a using the dry single-action press device 25 will be described with reference to FIGS. 7(a) and 7(b).

FIG. 7(a) is a plan view showing a state in which the lower die 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 E-shaped molding hole 21a of the same mold 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 from below into the E-shaped molding hole 21a formed in the mold frame 21, and the granulated powder 24 made of a magnetic material is filled into the E-shaped molding hole 21a, and the upper mold 2 is inserted from above.
2 is inserted and pressurized to mold the E-shaped core la.

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, the central magnetic leg 2a, the first side magnetic leg 3a, and the second side magnetic leg of the E-shaped core 1a are formed on substantially horizontal planes and are therefore molded. 4
The upper and lower surfaces of each of a are formed on the same plane.

According to the single-acting press device 25, the E-type core 1a
has a uniform density in each part, and since the single-acting press 25 operates simply, the single-acting press 25
It has the characteristics of a small and simple structure, a fast molding speed (and suitable for mass production).

Note that when iron powder is used as the magnetic material, a powder magnetic core is formed by pressure molding, and when ferrite powder is used, a binder is added to the ferrite powder and granulated. A ferrite core is formed by pressure molding and further firing.

Next, the E-type core 11 is
A manufacturing method for manufacturing the same will be explained with reference to FIGS. 8(a) and (b).

FIG. 8(a) is a plan view showing a state in which the lower die 33 is fitted into the formwork 31 of the double-acting press device 35, and FIG.
), the granulated powder 34 made of a magnetic material filled in the rectangular molding hole 31a of the mold frame 31 is inserted into the upper mold 32 and the lower mold 3.
FIG. 3 is a cross-sectional view taken along line B-B showing a state in which pressure is applied.

A lower mold 33 is fitted from below into a rectangular molding hole 31a formed in the formwork 31, and granulated powder 34 made of a magnetic material is filled into the rectangular molding hole 31a, and an upper mold 32 is fitted from above. Pressure is applied by inserting the E-type core 1.
1 is molded.

At this time, the first lower mold pressing surface 33a and the second lower mold pressing surface 33b of the lower mold 33 are opposite to the upper mold pressing surface 32a of the upper mold 32.
is configured to double-act and operate, and the central magnetic leg 12 is molded approximately at the center of the front of the yoke portion 15, and the first side magnetic leg 13 and the second side magnetic leg 14 are molded. It is supposed to be done.

According to the double-acting press device 35 described above, the first
This is because the lower mold pressure surface 33a and the second lower mold pressure surface 33b double-act to press the granulated powder 34.

It is difficult to mold the granulated powder 34 to have a uniform density, and the first lower mold pressing surface 33a
There is a risk that micro-cracks etc. will occur in the E-shaped core 11 due to the double-acting pressure applied by the press machine 35, etc., and as the double-acting press device 35 increases in size, the operation control of the device 35 becomes complicated. Moreover, the molding speed was slow, making it unsuitable for mass production.

For this reason, a method of manufacturing an E-type core as shown in FIGS. 9(a) to 9(d) has been proposed.

According to this method, a molded member 48 having a rectangular cross section is manufactured by granulating a magnetic material such as ferrite powder, a binder, etc. as granulated powder, and molding it using a single-action press machine (not shown). (Figure (a))
.

The molded member 48 is fired or pre-fired (main firing is performed at the stage where the E-shaped core forming process is completed), and then two cutting grooves 47a, 4 are formed along the longitudinal direction of the molded member 48.
7b, for example, by cutting using a lathe or the like (FIG. 7(b)).

Next, the molded member 48 is sequentially cut to a predetermined width (FIG. 4(C)).

Through the above steps, the E-type core 41 has grooves on both sides of the central magnetic leg 42, and the first side magnetic leg 43 and the second side magnetic leg 4
4 are arranged and formed, and a yoke portion 45 is formed to connect one end of each of the central magnetic leg 42, the first side magnetic leg 43, and the second side magnetic leg 44.

Furthermore, the upper surface of the central magnetic leg 42 and the upper surface of the yoke part 45 in the E-shaped core 41 are cut as a central magnetic leg cutting part 46a and a yoke part cutting part 46b, respectively, and the cutting groove part 46
is processed.

After that, a coil bobbin (not shown) is attached to the central magnetic leg 42.
A transformer or the like is constructed by being fitted into the.

At this time, the upper part of the coil bobbin fitted to the central magnetic leg 42 has the cutting groove 46 formed therein.
Since the first magnetic leg 43 and the second magnetic leg 44 disposed on both sides of the cutting groove 46 are prevented from protruding from the upper surface, they can be stably mounted on electronic circuit boards, etc., and are small and low profile. contributed to the

According to the method for manufacturing the E-type core described above, there is no need to use the double-acting press device 35, and the E-type core 41 can be manufactured using a simple device and process.

(Problems to be Solved by the Invention) However, according to the above-mentioned conventional E-type core manufacturing method, the E-type core is structurally designed so that the coil bobbin can be efficiently housed and the height can be made low. When attempting to form the magnetic material using a pressure press, a double-acting press device must be used as the pressure press device, which makes it difficult to mold the magnetic material to a uniform density. There is a risk that cracks may occur in the E-type core due to internal stress, and the double-acting press itself becomes large, making operation control complicated, and the molding speed is slow, making it unsuitable for mass production. was there.

Further, according to the manufacturing method of manufacturing the E-shaped core by molding a magnetic material, cutting grooves, cutting to a predetermined width, and further cutting a part of the central magnetic leg and yoke part, Although it is no longer necessary to use the double-acting press device, there is a problem in that the number of manufacturing steps is increased compared to when a single-acting press device is used.

Furthermore, in manufacturing methods that use the double-acting press equipment and manufacturing methods that require molding, grooving, cutting, and machining, E.
When constructing a transformer etc. by abutting and combining type cores or type 1 and E type cores, it is usually necessary to perform surface polishing on the contact surfaces of each type, and in addition to the above steps, this surface polishing step is also necessary. There was a problem that .

The present invention has been made in view of the above circumstances, and it manufactures an E-type core with a structural design that effectively utilizes the dimensions of each part through a simple manufacturing process without using large-scale molding equipment that is difficult to control. The present invention provides a method for manufacturing an E-type core that can be used.

(Means for Solving the Problem) In order to achieve the above object, the present invention includes a central magnetic leg,
An E-type core having a pair of side magnetic legs arranged opposite to each other so as to sandwich the central magnetic leg, and a yoke portion that connects one end of the central magnetic leg and one end of each of the pair of side magnetic legs to each other. In the manufacturing method, a date-shaped shape having a pair of side columns, a pair of common columns connecting both ends of the pair of side columns, and a central common column connecting the center portions of the pair of side columns. By molding a magnetic material and cutting one side of the molded body so as to divide it into a plurality of parts, the central magnetic legs are formed on the common column and the central common column, and the side columns are formed. The above object is achieved by manufacturing an E-shaped core by using the side magnetic legs and cutting the side columns and the central common column.

Further, the present invention provides a method for forming the common column and the central common column by molding the magnetic material into a sun-shaped shape and cutting it to form a plurality of convex portions on one sun-shaped surface of the molded body. The above object is achieved by forming the central magnetic leg in the core, using the side column as the side magnetic leg, and cutting the side column and the central common column to produce an E-shaped core. be.

(Function) In the present invention, a single-acting press or the like is used to press a magnetic material onto a pair of side columns, a pair of common columns connecting both ends of the pair of side columns, and a central portion of the pair of side columns. By molding it into a sun-shaped shape having a connecting central common pillar, cutting one sun-shaped face of the molded body to divide it into a plurality of parts, and further cutting the side pillars and the central common pillar. At the same time, two pairs of E-type cores each having a central magnetic leg, a pair of side magnetic legs disposed opposite to each other so as to sandwich the central magnetic leg, and a yoke portion connecting one end of each of the central magnetic legs to each other are combined. can be manufactured.

In addition, in the present invention, the previous IE! By molding a magnetic material into a sun-shaped shape, cutting it to form a plurality of convex parts on one sun-shaped surface of the molded body, and cutting the side pillars and the central common pillar, the central magnetic material is formed. E having a leg, a pair of side magnetic legs arranged opposite to each other so as to sandwich the central magnetic leg, and a yoke portion that connects one end of the central magnetic leg and one end of each of the pair of side magnetic legs to each other. Two pairs of mold cores can be manufactured at the same time.

In addition, two pairs of E-type cores are manufactured by molding the magnetic material into a date shape using a small and simple device such as a single-acting press, and cutting and cutting the date shape. Therefore, there is no need to use a large and complicated control device such as a double-acting brace.

Further, in the E-type core manufactured by the above manufacturing process, the width of the central magnetic leg is narrower than the width of the pair of side magnetic legs, so that the coil bobbin is fitted into the central magnetic leg. At this time, the amplitude of one coil of the coil bobbin does not protrude beyond the width of the pair of side magnetic legs.

Furthermore, according to the manufacturing process, when cutting is performed to form a plurality of convex portions on one day-shaped surface of the day-shaped molded body, the E-shaped cores are combined with each other. Surface polishing of the contact surface can be performed at the same time.

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

FIG. 1(a) is a perspective view showing an example of the molding process according to the method for manufacturing an E-shaped core of the present invention, and FIG. 1(b) is a day molded member molded by the molding process according to the same example. FIG. 1(c) is a perspective view showing an example of the cutting process according to the same example, and FIG. 1(d) shows a day-shaped core formed by the cutting process according to the same example. A perspective view, FIG. 1(e) is a perspective view showing two pairs of E-shaped cores formed by the cutting process according to the same example, and FIG. 1(f) is a perspective view showing the two pairs of E-shaped cores formed by the manufacturing method according to the same example. A perspective view showing an E-type core, FIG. 2(a) is a front view showing an E-type core manufactured by the manufacturing method according to the same example, and FIG. 2(b) is a front view showing the E-type core manufactured by the manufacturing method according to the same example. FIG. 3(a) is a cross-sectional view showing an xx section of the E-type core made by the manufacturing method, FIG.
4(a) is a plan view illustrating a state in which E-type cores according to the same embodiment are combined; FIG. b) is a plan view illustrating a state in which E-shaped cores according to the same embodiment are combined.

As shown in FIG. 1(a), approximately in the center of the formwork 51,
A rectangular rectangular hole 51d is formed by molding or the like, and a first columnar mold 51b is formed inside the rectangular hole 51d.
By arranging the second pillar type 51c, the sun type hole 5
1a is formed, and the date-shaped hole 51a is female-shaped.

From below the date hole 51a of the formwork 51, the date hole 5
A lower mold 53 having the same shape as 1a is inserted as a male mold at its upper part as shown by arrow I in FIG.

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

From above the sun-shaped hole 51a filled with the granulated powder 54,
An upper die 52 having the same shape as the date hole 51a and the lower die 53 serves as a male die, and the lower part thereof is inserted as shown by the arrow ■ in the figure.

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

The date molded member 61 has a pair of first Il on the front and back.
A pillar 62 and a second III pillar 63 are arranged, and both ends of each of the first side pillar 62 and second side pillar 63 are connected by a pair of first common pillar 64 and second common pillar 65, respectively. The center portions of each of the first side pillar 62 and the second side pillar 63 are connected by a central common pillar 66, and the upper mold pressing surface 52a of the upper mold 52 and the lower mold pressing surface 53a of the lower mold 53 are configured. The first side column 62, the second side column 63, and the first common column 6 of the day molded member 61 are flat-processed.
The upper and lower surfaces of each of the fourth and second common columns 65 are formed on the same plane.

Next, as shown in FIG. 1(c), a grinder device 73 in which twin wheels of a first disc type grinder 71 and a second disc type grinder 72 made of an abrasive material etc. are pivotally attached to a rotating shaft 74. is rotationally driven in the direction of the arrow (■) in the figure by a drive device (not shown), and the date molding member 61 is moved in the direction of the arrow (■) in the figure by a moving mechanism (not shown).

Therefore, the common pillar 64, the second common pillar 65 and the central common pillar 66 of the day molded member 61 are connected to the first side pillar 62 and the second common pillar 66.
Along the inner edge of the side post 63, the grinder device 73
The cutting depth is determined by the width of the first cutting surface 71a and the second cutting surface 72a and the installation height of the rotating shaft 74 of the grinder device 73, and as shown in FIG. 1(d), the Japanese core 80 is cut. is formed.

The day-shaped core 80 is formed into the first common pillar 6 by the cutting process.
4. On both sides of the second common column 65 and the central common column 66, the first
A cutting groove 86 and a second cutting groove 87 are formed.

Next, as shown in FIG. 1(e), in the longitudinal direction of the first common column 64 and the second common column 65 in the Japanese type core 80, the first side column 62 and the second side column 63 At the same time, the center common column 66 is cut along the approximate center portion in the longitudinal direction, and the first side column 62 is cut into the first side column 62a, the first side column 62b, and the first side column 62b. 1 side pillar 62
c and the first side pillar 62d, the second side pillar 63 is connected to the second side pillar 63a, the second side pillar 63b, the second side pillar 63c and the second side pillar 63d, and the center common pillar 66 is connected to the first center common pillar 66
a and the second central common column 66b, respectively,
A first E-type core 8La, a second E-type core 81b, a third E-type core 81c, and a fourth E-type core 81d are formed.

Here, taking the first E-type core 81a as an example, as shown in FIG. 1(f), the upper part of the first common pillar 64 becomes the central magnetic leg 82, and the lower part of the first common pillar 64 becomes The first side post 62a and the front first side post 63a serve as a first side magnetic leg 83 and a second side magnetic leg 84, respectively.

At this time, in the first E-type core 81a, as shown in FIG. 2(a), the upper mold pressing surface 52a and the lower mold pressing surface 53a of the single-acting type brace device 55 form a flat surface as described above. By this, the central magnetic leg surface 82a of the median value #J82 of the day type core 81a and the first side magnetic leg surface 83a of the first side magnetic leg 83,
The second side magnetic leg surface 84a of the second side magnetic leg 84 is arranged on the same plane, and the lower surface of the date-type core 81a is also flat.

In addition, in the day type core 81a, as shown in FIG. 2(b), the area of the central magnetic leg surface 82a is twice the area of the first side magnetic leg surface 83a and the second (III) magnetic leg surface 84a. At the same time, the height Hl of the central magnetic leg 82 is higher than the first side magnetic leg 83.
And the height is lower than the height H2 of the second side magnetic leg 84.

That is, as shown by imaginary lines in FIG. 1(d) and FIG. 2(b), a coil bobbin 88 made of a coil or the like wound with enameled wire or the like is fitted into the central magnetic leg 82. When this is done, the upper part of the winding of the coil bobbin 88 no longer protrudes from the height H2 of the first side magnetic leg 83 and the second side magnetic leg 84.

According to this embodiment, the small and simple single-acting breath device 5
5, the magnetic material is molded into a date-shaped molded member 61, and the inner edges of the first side pillar 62 and the second side pillar 63 are shaped so that one date-shaped face of the date-shaped molded member 61 is divided into a plurality of parts. By cutting the first common column 64, second common column 65, and center common column 66 along The common column 65 is cut in the longitudinal direction at approximately the center of the first side column 62 and the second side column 63, and the central common column 66
By cutting the central common column 66 along approximately the center in the longitudinal direction of the
can be manufactured, eliminating the need for complicated manufacturing processes.

In addition, the coil bobbin is housed efficiently (and the four day-shaped cores 8 are formed to have a low profile so that they can be mounted on electronic circuit boards, etc.).
In manufacturing 1a, 81b, 81c, and 81d,
Since there is no need for a double-acting press device that is large and has complicated operation control, the magnetic material can be press-molded with uniform density, the molding speed is improved, and mass production is possible.
Furthermore, it is possible to prevent microcracks and the like occurring in the day-shaped core.

Furthermore, the Japanese type core 81a manufactured by the above manufacturing process
, 81b, 81c, and 81d are the heights H of the central magnetic legs 82.
, is formed to have a lower height than the height H of the pair of first side columns 62 and second side columns 63, so that when the coil bobbin 88 is fitted to the central magnetic leg 82, the coil bobbin 88
The amplitude of one of the coils of the pair of first side pillars 62 and the second
They do not protrude from the side pillars 63 (therefore, the transformers and the like in which the Japanese type cores 81a, 81b, 81c, and 81cl are incorporated can be stably mounted on an electronic circuit board, etc.).

Note that the first cutting surface 71a of the first disc type grinder 71 and the second disc type grinder 72 of the grinder device 73
When each ridge of the second cutting surface 72a is curved, the date molded member 61 has the first cutting groove 86 and the second cutting groove 87 cut by the grinder device 73.
By applying a curved surface to the lower portion of each of the E-type cores 81a, 81b, 81c, and 81d, it is possible to prevent microcracks from occurring in the E-type cores 81a, 81b, 81c, and 81d.

Further, the ridges of the first disc type grinder 71 and the second disc type grinder 72 of the grinder device 73 are not limited to being curved, for example, the first disc type grinder 71 and the second disc type grinder 72 Taper processing may also be applied to.

Furthermore, by fitting three coil bobbins into the first common column 64, second common column 65, and center common column 66 of the day type core 80 which is obtained by cutting the day type molded member 61 by the grinder device 73, the transformer etc. may be configured.

Next, another embodiment of the present invention will be described with reference to FIG.

In this embodiment, the same parts as in the previous embodiment are given the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 1(a), granulated powder 24 made of a magnetic material is molded into a date molded member 61 by a single-acting press 55. As shown in FIG.

As shown in FIG. 3(a), the grinder device 91 includes a central polishing grinder 92 sandwiched between the first disc type grinder 71 and the second disc type grinder 72, and each of the grinders. A first abrasive grinder 93 and a second abrasive grinder 94 disposed on the sides of the abrasive grinder 94 are each pivotally attached to a rotating shaft 74.

At this time, the central polishing grinder 92, the first polishing grinder 93, and the second polishing grinder 94 cut the first disc in accordance with the cutting depth determined by the installation height of the rotating shaft 74 of the grinder device 91. The diameter is smaller than that of the mold grinder 71 and the second disc type grinder 72, and the upper surfaces of the common pillar 64, the first side pillar 62, and the second side pillar 63 are polished. .

By cutting with the grinder device 91, a first cutting groove 86 and a second cutting groove 87 are formed, and the first side post polished surface 62e of the first side post 62 and the first side post polished surface 62e of the second side post 63 are further formed. The second side post polished surface 63e and the first common post 64
The common column polished surface 64e, the second common column polished surface 65e of the second common column 65, and the central iron column polished surface 66 of the central common column 66.
e and are respectively surface-polished to form the date-shaped core 100.

The day-shaped core 100 is cut in the longitudinal direction of the first common column 64 and the second common column 65 at approximately the center of the first side column 62 and the second side column 63, and is cut at the center common column 62 and the second side column 63, and By cutting the pillar 66 approximately along the center in the longitudinal direction, the first E-type core 101 and the second E-type core 102 are included.
Four day-shaped cores are formed.

At this time, taking the first E-type core 101 as an example, the first common column polished surface 64e of the first common column 64 that has been polished
, the first side post polished surface 62e of the first side post 62 and the second side post 6
The second side pillar polishing surface 63e of No. 3 is the center magnetic leg polishing surface 82b of the central magnetic leg 82, the first side magnetic leg polishing surface 83b of the first side magnetic leg 83, and the second side of the second side magnetic leg 84, respectively. Magnetic leg polishing surface 84
b.

The first E-type core 101 and the second E-type core 102 are combined, and the coil bobbin 88 is fitted to the central magnetic leg 82, etc., to form a transformer, etc., as shown in FIG. 3(b). .

At this time, the transformer and the like are connected to the central magnetic leg polishing surface 82b, the 1111Fi single leg polishing surface 83b, and the second side magnetic leg polishing surface 84b of the first E-type core 101, and the respective corresponding surfaces of the second E-type core 102. are brought into contact with each other and fixed by fixing fittings (not shown), but the central magnetic leg polishing surface 82b, the first side magnetic leg polishing surface 83b, the second side magnetic leg polishing surface 84b, and the like of the first E-type core 101 Since the corresponding surfaces of the second E-type core 102 are surface-polished, the corresponding surfaces can be brought into close contact with each other, without degrading the magnetic properties of the transformer, etc. (and ensuring reliable assembly). It can be carried out.

Furthermore, according to the manufacturing process, when cutting is performed to form a plurality of convex portions on one date face of the date-shaped molded body, the central magnetic legs and Since surface polishing of the contact surfaces of the pair of side magnetic legs on which the sun-type cores are combined can be performed simultaneously, the surface polishing process of the corresponding contact surfaces can be omitted.

Next, another embodiment of the present invention will be described with reference to FIG.

Similarly, in this embodiment, the same parts as in the previous embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted.

The molded part 61 molded in FIG. 1(a)
As shown in FIG. 4(a), the grinder device 9
One central polishing grinder 92 is cut by a grinder device 96 that is replaced with a central cutting grinder 97 having a larger diameter than the central polishing grinder 92, thereby forming a date core 111.

At this time, for example, the first
The upper part of the common column 64 is cut to form a central magnetic leg 98 having a lower height than the first common column 64, and the upper surface of the central magnetic leg 98 has a cut surface 98a of the central magnetic leg which is surface-polished at the same time as cutting. It consists of

The day-type core 111 is located in the longitudinal direction of the first common column 64 and the second common column 65, and in the longitudinal direction of the first side column 62 and the second common column 65.
By cutting approximately at the center of the side column 63 and along the longitudinal center of the central common column 66, four day-shaped cores including the first E-type core 106 and the second E-type core 107 are formed. A core is formed.

At this time, taking the first E-type core 106 as an example, the first common column polished surface 64e of the first common column 64 that has been cut and polished, and the first side column polished surface 62e of the front first side column 62. The second side column polished surface 63e of the second side column 63 is the center magnetic leg cutting surface 98a of the center magnetic leg 98, the first side magnetic leg polished surface 83b of the first side magnetic leg 83, and the second side magnetic leg, respectively. 84 second side magnetic leg polishing surface 84b.

The first E-type core 106 and the second E-type core 107 are combined, and the coil bobbin 88 is fitted onto the central magnetic leg 98, etc., to form a transformer, etc., as shown in FIG. 3(b). .

At this time, a central gap 1 exists between the central magnetic leg 98 of the first E-type core 106 and the opposing central magnetic leg of the second E-type core 107.
10 are provided.

The central gap 110 can be formed by arbitrarily providing a gap.
The magnetic characteristics of transformers etc. can be adjusted.

Therefore, according to this embodiment, the central gap 110 for magnetic adjustment of a transformer or the like in which an E-type core is incorporated can be formed simultaneously with the cutting process, and surface polishing can also be performed.

Note that when iron powder is used as the magnetic material, a powder magnetic core is formed by pressure molding, and when ferrite powder is used, a binder is added to the ferrite powder and granulated. A ferrite core is formed by pressure molding and further firing.Although in this example a single-acting press device was used to press the granulated powder, the present invention is not limited to this. For example, a wet extrusion molding machine or the like may be used.

Further, in this embodiment, a rotating disc-shaped grinder device is used for cutting, but the present invention is not limited to this, and for example, a rotating belt-shaped sander or the like may be used.

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

(11) Molding the magnetic material into a date-shaped molded member using a small and simple single-acting press, etc., cutting one of the date-shaped parts of the date-shaped molded member so as to divide it into a plurality of parts, and then By cutting the molded member, two pairs of E-type cores can be manufactured, so it is possible to simultaneously obtain two pairs of E-type cores to be incorporated into a transformer, etc.
This has the excellent effect of eliminating the need for a complicated manufacturing process and simplifying the manufacturing process.

(2) In addition, the magnetic material is molded into a date-shaped molded member, and a plurality of convex portions are formed on one of the date-shaped surfaces of the date-shaped molded member, and then the date-shaped molded member is By cutting, two pairs of E-type cores can be manufactured, so it is possible to simultaneously obtain two pairs of E-type cores to be incorporated into transformers, etc., and it also eliminates the need for complicated manufacturing processes, which simplifies the manufacturing process. It has the excellent effect of being simple.

(3) In addition, the E-shaped core, which accommodates the coil bobbin efficiently and is formed to have a low profile so that it can be mounted on an electronic circuit board, etc., is not molded using a double-acting press device that is large and has complicated operation control. , the magnetic material is molded into a molded member using a single-acting press machine, processed and cut to produce the E-shaped core, so the magnetic material is press-molded with uniform density. At the same time, the molding speed is improved, mass production becomes possible, and furthermore, it has the excellent effect of being able to prevent microcracks and the like that occur in the E-shaped core due to pressurization by a double-acting press device.

(4) In addition, in the E-type core manufactured by the above manufacturing process, the width of the central magnetic leg is narrower than the width of the pair of side magnetic legs, so that the coil bobbin is fitted into the central magnetic leg. When installed, the amplitude of one coil of the coil bobbin does not protrude beyond the width of the pair of side magnetic legs, so that the transformer etc. in which the E-type core is incorporated in an electronic circuit board etc. can be stably mounted. It has the excellent effect of being able to be mounted.

(5) Furthermore, when using E-type cores or a combination of I-type and E-type cores, it is necessary to perform surface polishing on the abutting surfaces of the cores, but the above manufacturing process According to the above, when performing cutting to form a plurality of convex portions on one sun-shaped surface of the sun-shaped molded body, surface polishing of the corresponding contact surface can be performed at the same time. The process can be eliminated, and the assembly can be performed reliably.

It has an excellent effect of preventing deterioration of magnetic properties.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view showing an example of the molding process according to the method for manufacturing a Japanese-type core of the present invention, and FIG. 1(b) is a Japanese-type molded member molded by the molding process according to the same embodiment. FIG. 1(c) is a perspective view showing an example of the cutting process according to the same example, and FIG. 1(d) shows a day-shaped core formed by the cutting process according to the same example. Perspective view. FIG. 1(e) is a perspective view showing two pairs of Japanese-type cores formed by the cutting process according to the same example, and FIG. 1(f) is a Japanese-type core formed by the manufacturing method according to the same example. FIG. 2(a) is a front view showing a day-type core manufactured by the manufacturing method according to the same example, and FIG. 2(b) is a front view showing a day-type core manufactured by the manufacturing method according to the same example. Cross-sectional view showing the X-x cross section of the mold core, Figure 3 (a)
3(b) is a perspective view showing an example of the cutting process of another manufacturing method according to the present invention, FIG. FIG. 4(b) is a plan view illustrating a state in which Japanese-type cores according to the same embodiment are combined; FIG. Figures (a) and (b) are perspective views showing a conventional Japanese-type core, Figure 6 is a perspective view showing another conventional Japanese-type core, and Figure 7 (a).
) is an explanatory diagram illustrating the manufacturing method of the Japanese type core using the conventional single-acting type brace, Figure 7 (b) is a cross-sectional view showing the A-A cross section of the single-acting type press, and Figure 8 (a) is the conventional method. FIG. 2 is an explanatory diagram illustrating a method for manufacturing a day-type core using a double-acting type breather. FIG. 8(b) is a sectional view showing the BB cross section of the double-acting type brace, and FIGS. 9(a) and 9(b) are explanatory diagrams illustrating the manufacturing process of the conventional day type core. 51 ・ 53 ・ 55 ・ 6 l ・ 62 ・ 64 ・ 7 l ・ 72 ・ 73 ・ 80 ・ 82 ・ 84 ・ Formwork, 52... upper mold, lower mold, 54... granulated powder, single acting mold Breath device, mouth molded member, first side post, 63... second side post, first common post, 65... second common post, first disc type grinder, second disc type grinder. Grinder device. Japanese type core, 81... Japanese type core. Central magnetic leg, 83...I side magnetic leg, second side magnetic leg, 85...Yoke part.

Claims (2)

[Claims] (1) A central magnetic leg, a pair of side magnetic legs arranged opposite to each other so as to sandwich the central magnetic leg, and a yoke portion that connects one end of the central magnetic leg and one end of each of the pair of side magnetic legs to each other. , a pair of side columns, a pair of common columns that respectively connect both ends of the pair of side columns, and a central common column that connects the center portions of the pair of side columns. The central magnetic leg is formed on the common column and the central common column by molding a magnetic material into a sun-shaped shape having , and cutting one sun-shaped surface of the molded body so as to divide it into a plurality of parts. At the same time,
E characterized in that the side pillars are used as the side magnetic legs, and the side pillars and the central common pillar are further cut to produce an E-shaped core.
Method of manufacturing mold core. (2) By molding a magnetic material into a sun-shaped shape and cutting it to form a plurality of convex portions on one sun-shaped surface of the molded body, the common pillar and the central common pillar are provided with the central magnetic material. A method for producing an E-type core, comprising forming legs, using the side columns as the side magnetic legs, and cutting the side columns and the central common column to produce an E-type core.