JP3794658B2 - Noise cut transformer and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transformer that blocks noise transmitted from a primary side coil to a secondary side coil, and more particularly to a transformer that is disposed between a power line and a device side circuit to prevent malfunction of the device.
[0002]
[Prior art]
In order to prevent noise transmission as a conventional technique, for example, as disclosed in Japanese Utility Model Publication No. 60-17882, means for preventing noise transmission by using a material having a low high-frequency effective permeability for the core, In addition, as shown in Japanese Utility Model Publication No. 57-18748, means for preventing transmission of noise by making the axis of the primary coil orthogonal to the axis of the secondary coil (hereinafter referred to as axis-orthogonal noise) A cut transformer) has been proposed.
[0003]
In particular, in the latter axially orthogonal noise cut transformer, the magnetic flux passing through the air away from the core does not interlink between the primary side coil and the secondary side coil. For this reason, noise from the primary side coil to the secondary side coil is not transmitted by the magnetic flux away from the core, and thus noise can be removed during power / signal transmission from the primary side to the secondary side.
[0004]
For example, as disclosed in Japanese Patent Application Laid-Open No. 2-199809, this noise cut transformer is configured by forming a ring-shaped core wound around a belt-like material and laminated from the inner diameter side to the outer diameter side. By twisting the two sides, the axes of the primary side coil and the secondary side coil attached thereto are made orthogonal to each other.
[0005]
[Problems to be solved by the invention]
The above-described axially orthogonal noise cut transformer is manufactured by clamping one side and twisting the opposite side as described in Japanese Patent Publication No. 7-56848, for example. However, it is necessary to apply a very large force to such processing, and a special processing machine is required. In addition, since it is a three-dimensional object having a thickness not only in the width direction of the belt-shaped material constituting the core but also in the lamination radial direction, the curvature is greatly different between the inner diameter and the outer diameter of the bending part, and the bending part is laminated. There was a problem that the strip-shaped material was shifted or wrinkled. For this reason, there is a problem that such bending work requires skill of workers and production efficiency is low.
[0006]
Therefore, the object of the present invention is to combine four cut cores, and to construct a noise-cutting transformer with an orthogonal axis center without requiring bending work. Is to propose a good noise cut transformer and a method of manufacturing the same.
[0007]
[Means for Solving the Problems]
The present invention is an axially orthogonal noise cut transformer in which an axial direction of a primary coil attached to a core and an axial direction of a secondary coil are orthogonal to each other, and each core is formed by laminating a plurality of plate materials. The four cut cores bent in the laminating direction and formed into side-surface L-shapes were used, and the end face of one cut core was sequentially connected so as to be in contact with the end face of the adjacent cut core. The above-described problems are solved by providing a noise cut transformer configured by forming.
[0008]
In addition, as a method of manufacturing the above-described noise-cut transformer, a step of forming an annular laminate by winding a belt-like material on the side surface of the core, and extracting the core, and then dividing the annular laminate into four Then, a step of forming four cut cores each having an L-shaped side surface, and a primary side coil and a secondary side coil are externally fitted to one side of two of the four cut cores, respectively. The other two cut cores are arranged between the process and the two cut cores on which the primary side coil and the secondary side coil are externally fitted, and the end face of the adjacent cut core is located at the front end of the one cut core. Proposing a noise cut transformer manufacturing method comprising: a step of forming an annular core in which the axial direction of the primary side coil and the axial direction of the secondary side coil are orthogonal to each other by connecting so as to be in contact with the side surface of the part You .
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the noise cut transformer of the present invention will be described with reference to FIGS. 1 is a perspective view of a noise cut transformer, FIG. 2 is a side view of the core, FIG. 3 is an explanatory view of the cut core, FIGS. 4 and 5 are explanatory views showing the manufacturing process of the cut core, and FIG. It is a disassembled perspective view of the core explaining the used assembly method of the core.
[0010]
A noise cut transformer (hereinafter simply referred to as a transformer) 1 according to the present embodiment is a transformer that is disposed between a power source (not shown) and a device, and is provided to prevent noise from the power source from being transmitted to the device. As shown in FIG. 1, the transformer 1 includes a core 3 configured by combining four cut cores 2 (2 </ b> A to 2 </ b> D), and a primary coil 4 and a secondary coil 5 attached to the core 3. Composed.
[0011]
The primary side coil 4 and the secondary side coil 5 are obtained by winding a predetermined number of electric wires (not shown) around the outer peripheral surfaces of the bobbins 4a and 5a, and the ends of the electric wires are drawn out as lead wires 4b and 5b. . The bobbins 4a and 5a have a quadrangular shape and the same inner diameter that can be fitted onto a cut core 2 described later.
[0012]
Each coil 4 and 5 is covered with a good conductive material such as metal foil, metal molding box, metal welding film, metal vapor deposition film, conductive paint, etc. By preventing the transition of noise due to electrostatic coupling as a shielding structure for drawing out the conductors 4c and 5c, the noise cut effect can be further enhanced.
[0013]
The coils 4 and 5 that are manufactured in advance as described later can be incorporated when the core 3 is assembled. For this reason, after the core is manufactured, the bobbin for rotating winding is not necessarily required as compared with the conventional structure in which the coil needs to be configured by rotating the bobbin and winding the electric wire afterwards. Therefore, for example, after winding the electric wire around the core material, the core material is removed and fixed with taping or an adhesive, and a bobbin is not required.
[0014]
The primary side coil 4 and the secondary side coil 5 are fitted on one side of the first cut core 2A and the third cut core 2C, respectively, and the first cut core 2A and the third cut core 2C are the second cut core. 2B and the 4th cut core 2D are connected, and the core 3 which became a three-dimensional cyclic | annular body is comprised (a structure is explained in full detail behind). In addition, the lead wire 4b of the primary side coil 4 is connected to the power source side, and the lead wire 5b of the secondary side coil 5 is connected to the device side.
[0015]
As shown in FIG. 1, each of the lead wires 4b and 5b is formed by twisting two electric wires together, and a magnetic flux passing through the air away from the core is linked to these lead wires 4b and 5b. However, since the induced electromotive forces of the respective electric wires are opposite to each other, they cancel each other and disappear, so that a transformer that hardly affects the power supply side and the device side can be configured.
[0016]
In addition, each cut core 2 and the core 3 comprised by these are each formed using the material with a low high frequency effective magnetic permeability. As such a material, for example, a silicon steel plate is selected.
[0017]
FIG. 2 is a side view of the core 3 taken from the viewpoint direction S of FIG. As shown in the figure, the core 3 is an annular body that is twisted 90 degrees alternately in the vertical and horizontal directions at eight locations, and when viewed from the same viewpoint direction S, the front part and the rear part overlap each other at right angles. have. The axes X and Y of the primary side coil 4 and the secondary side coil 5 that are externally fitted to the front part (first cut core 2A) and the rear part (third cut core 2C) are also orthogonal to each other. For this reason, among the magnetic fluxes generated from the primary coil 4, the magnetic flux that passes through the air without passing through the core 3 does not interlink with the secondary coil 5.
[0018]
The electric power / signal input to the primary side coil 4 is converted into magnetism by electromagnetic induction action, and is converted back to electric power / signal again by the secondary side coil 5 through the core 3 and taken out. At this time, since the core 3 has low effective high-frequency magnetic permeability, even if high-frequency noise is included on the power source side (primary coil 4), the core 3 is removed during this time via the core 3, and the device side (two No noise is transmitted to the secondary coil 5).
[0019]
In addition, as described above, the magnetic flux generated from the primary coil 4 and passing through the air does not interlink with the secondary coil 5. For this reason, the primary side coil 4 and the secondary side coil 5 are not magnetically coupled through a path other than the core 3, and noise can be prevented from being transmitted through a path that bypasses the core 3.
[0020]
As described above, when the transformer 1 transmits power / signal from the power source side (primary side coil 4) to the device side (secondary side coil 5), noise included therein can be surely removed. Therefore, malfunction of the device due to noise can be prevented. On the contrary, even if noise is generated from the device side, it can be prevented from leaking to the power source side, and contamination of the power source can be prevented.
[0021]
The core structure will be described with reference to FIGS. 3A is a side view of the cut core, and FIG. 3B is a front view of the cut core. The cut core 2 is a side L-shaped block in which a plurality of metal plates are laminated, and is largely curved at the center as shown in FIG.
[0022]
On both side surfaces 2e and 2f and both end surfaces 2c and 2d of the cut core 2, the laminated surfaces 2x and 2y of the metal plate material appear, respectively. At least the laminated surface 2x at one end and the laminated surface 2y at one side are ground and flattened.
[0023]
Here, the lengths 11 and 12 of both sides 2a and 2b of the cut core 2 orthogonal to each other have the same length. The end faces 2c and 2d appearing at the ends of both sides 2a and 2b have the same length in both height m1 and width m2.
[0024]
The manufacturing method of the cut core 2 is demonstrated using FIG.4 and FIG.5. First, as shown in FIG. 4, a metal strip 8 a is wound around the core material 7 to manufacture the annular laminate 8. At this time, the core material 7 used for this work is a rod having a square cross section, and the central opening of the annular laminate 8 has a front square shape. And after winding the metal strip 8a until it becomes predetermined thickness, the core material 7 is extracted and the cyclic | annular laminated body 8 is taken out.
[0025]
Next, as shown in FIG. 5, it is divided into four parts along a cutting line 8b passing through the center of each side of the annular laminate 8 so that the corner of the annular laminate 8 is centered. Since the annular laminated body 8 is a square with the same sides and rounded corners, the divided parts are L-shaped members each having a bent center. And this member is used as the cut core 2 by grinding and surface-treating the laminated surface 2x of the end surfaces 2c and 2d exposed to the outside and the laminated surface 2y of the side surfaces 2e and 2f exposed similarly.
[0026]
Note that the metal strip 8a may be divided into the cut cores 2 as described above by forming the annular laminate 8 and then fixing it by impregnating the adhesive between the laminates or fastening it by binding. , Will not peel off.
[0027]
A method for configuring the core 3 by combining the cut cores 2 manufactured as described above will be described with reference to FIG. As shown in the figure, one cut core 2 is sequentially connected so that one end face 2c is in contact with a side face 2e of another adjacent cut core 2. Cut-core bonding is performed by fastening with an adhesive, welding, or binding.
[0028]
In each connecting portion, the side surfaces 2e and 2f of one cut core 2 are connected so as to be always orthogonal to the side surfaces 2e and 2f of the other cut core 2. And according to this rule, the core 3 which is a cyclic | annular body is comprised by connecting the 1st thru | or 4th cut core 2A-2D in four places. That is, the core 3 is refracted by 90 degrees in the three-dimensional direction at the bent portion of each cut core 2 and the connecting portion between the cut cores 2 to form a geometrically three-dimensional annular body. .
[0029]
At this time, the end surface 2c and the side surface 2e of the cut core 2 are both the laminated surfaces 2x and 2y, and the laminated surfaces 2x and 2y are in contact with each other between the adjacent cut cores 2 at the connecting portion. For this reason, good magnetic permeability can be secured even in the connecting portion, and the core 3 having sufficient performance can be configured without being integrated.
[0030]
The primary side coil 4 and the secondary side coil 5 are manufactured in advance by winding an electric wire around the bobbins 4a and 5b, and when the core 3 is assembled, the primary side coil 4 and the secondary side coil 5 are externally fitted to one side of the opposed cut cores 2A and 2C. Thus, the transformer 1 is configured (see FIG. 1). As described above, these coils 4 and 5 do not require a bobbin for rotating and winding an electric wire as in the prior art, and a coil without a bobbin can also be used.
[0031]
In this way, by using four cut cores formed in an L shape and connecting the front face of one cut core to the side face of the adjacent cut core in order, the sides on both sides are orthogonal. The core to be performed can be configured easily. For this reason, compared with the conventional transformer which twisted the core which is an integral annular body, and the axial center of both coils was made orthogonal, a large-sized processing machine is not required and the stress process etc. of the part to be twisted are performed. Since this is not necessary, even a non-skilled worker can easily configure a noise-cut transformer with an orthogonal axis.
[0032]
In addition, when a conventional integral core is used, after the above-described twisting operation of the core, a split bobbin is attached on the core, and then a coil must be formed by winding an electric wire around the bobbin. On the other hand, in the present invention, since a coil configured in advance only needs to be attached after the fact, the transformer is excellent in production efficiency.
[0033]
In the above embodiment, the dimensions of each cut core 2 are set to be l1 = l2 and m1 = m2, but the present invention is not necessarily limited to this condition. For example, a horizontally long core can be configured by setting l1> l2, and a core having a rectangular cross section can be configured by setting two as m1> m2 and the other two as m1 <m2. You can also Moreover, in the said Example, although the whole laminated surfaces 2x and 2y of the cut core 2 were ground, you may grind the minimum part which both contact.
[0034]
【The invention's effect】
As described above, in the noise cut transformer of the present invention, such a shape can be easily configured by assembling four cut cores when orthogonally facing opposite sides. Therefore, it is possible to configure an axially orthogonal type noise-cut transformer that does not require skill in core manufacturing work and has a good production efficiency as compared with the prior art.
[0035]
Further, compared to the conventional technique using an integral core, a coil can be manufactured in advance, and this can be incorporated at the time of manufacturing the core. Therefore, from this point, the noise cut transformer is excellent in production efficiency.
[0036]
In addition, according to the method for manufacturing a noise cut transformer of the present invention, four L-shaped cut cores laminated with plate materials can be easily manufactured with dimensions aligned with each other. By using the die cut core, it is possible to easily make an axially orthogonal noise cut transformer.
[Brief description of the drawings]
FIG. 1 is a perspective view of a noise cut transformer.
FIG. 2 is a side view of a core used in a noise cut transformer.
3A is a side view of a cut core, and FIG. 3B is a front view of the cut core.
FIG. 4 is an explanatory view showing a method for manufacturing a cut core.
FIG. 5 is an explanatory view showing a method for manufacturing a cut core.
FIG. 6 is a perspective view showing an assembly structure of a core using cut cores.
[Explanation of symbols]
X ... axis of primary coil Y ... axis of secondary coil 1 ... transformer 2 ... cut core 2A ... first cut core 2B ... second cut core 2C ... third cut core 2D ... fourth cut core 2c, 2d ... end face 2e, 2f ... side face 2x ... cut core end face laminated face 2y ... cut core side face laminated face 3 ... core 4 ... primary coil 5 ... secondary coil 8 ... annular laminate

Claims (2)

A transformer in which a primary coil and a secondary coil are fitted on both sides of an annular core, and the core is configured so that the axial direction of the primary coil and the axial direction of the secondary coil are orthogonal to each other. And
The core uses four cut cores, each of which is formed by laminating a plurality of plate materials and bent in the laminating direction to form an L-shaped side surface. A noise cut transformer comprising: a ring-shaped body that is sequentially connected so as to be in contact with each other. Wrapping the belt-like material on the side surface of the core material and winding it to form an annular laminate,
After extracting the core material, dividing the annular laminate into four, and forming four cut cores each having an L-shaped side surface;
Out of these four cut cores, a step of externally fitting a primary side coil and a secondary side coil to one side of the two cut cores,
The other two cut cores are arranged between the two cut cores on which the primary coil and the secondary coil are externally fitted, and the front face of one cut core is placed on the side face of the adjacent cut core. A step of forming an annular core in which the axial direction of the primary side coil and the axial direction of the secondary side coil are orthogonal by connecting so as to be in contact with each other;
A method for manufacturing a noise cut transformer, comprising:

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