JP2006013168A - Coil and line filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coil which can be fixed to a substrate with simple constitution and made small-sized and short on the whole while fixed to the substrate, and a line filter mounted with the coil. <P>SOLUTION: A plurality of 1st through holes are bored in the substrate 10, a plurality of 2nd through holes 21A and 21B are formed in a plate type core 20 at positions corresponding to the 1st through holes 11A and 11B, and a core 20 is fitted on one surface of the substrate 10. Then 1st and 2nd coil conductors 31 and 32 which form a common mode choke coil together with the core 20 are inserted into the 1st through hles 11A and 11B and 2nd through holes 21A and 21B, and wound around the core 20 while fixing the core 20 to the substrate 10. In a free area on the substrate 10, a circuit component is mounted and the 1st and 2nd coil conductors 31 and 32 function as fixing members, so there is no need for newly providing a fixing member for mounting. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a coil having a core and a winding, and a line filter that suppresses noise propagating on conductive lines such as a power supply line and a signal line.

  Power electronics devices such as switching power supplies, inverters, lighting circuits for lighting devices, and the like have a power conversion circuit that converts power. The power conversion circuit has a switching circuit that converts direct current into rectangular alternating current. For this reason, the power conversion circuit generates a ripple voltage having a frequency equal to the switching frequency of the switching circuit and noise associated with the switching operation of the switching circuit. This ripple voltage and noise adversely affect other devices. Therefore, it is necessary to provide a means for reducing ripple voltage and noise between the power conversion circuit and another device or line.

  Recently, power line communication has been considered promising as a communication technique used in building a communication network in the home, and its development is being promoted. In power line communication, communication is performed by superimposing a high-frequency signal on the power line. In this power line communication, noise is generated on the power line due to the operation of various electric / electronic devices connected to the power line, which causes a decrease in communication quality such as an increase in error rate. Therefore, a means for reducing noise on the power line is required. In power line communication, it is necessary to prevent a communication signal on the indoor power line from leaking to the outdoor power line.

  In order to suppress these noises, it is effective to provide a line filter in a power supply line, a signal line, or the like. As the line filter, a filter including an inductance element (inductor) and a capacitor, a so-called LC filter is often used. The LC filter includes a T-type filter and a π-type filter in addition to one having one inductance element and one capacitor. A general noise filter for electromagnetic interference (EMI) countermeasures is also a kind of LC filter. A general EMI filter is configured by combining discrete elements such as a common mode choke coil, a normal mode choke coil, an X capacitor, and a Y capacitor.

  Noise that propagates through two conductive lines includes normal mode (differential mode) noise that causes a potential difference between the two conductive lines, and common mode noise that propagates through the two conductive lines in the same phase. There is.

  Patent Document 1 describes an example in which a noise filter is configured by mounting a toroidal type common mode choke coil on a wiring board. Patent Document 2 describes an example in which a noise filter is configured by mounting a bobbin type common mode choke coil on a wiring board.

In Patent Document 3, four rows of through-holes plated with through-holes are provided on a ferrite substrate, and conductive paint is printed on the upper and lower surfaces of the ferrite substrate so that adjacent rows of through-holes are connected. An example in which a flat coil is formed is described.
Japanese Utility Model Publication No. 5-6820 Japanese Patent Laid-Open No. 7-15269 Japanese Examined Patent Publication No. 6-66192

  With recent miniaturization of electronic devices, it is desirable to reduce the size of line filters. In particular, in the case of a line filter used for a power supply line, it is often provided around the power supply circuit, and it is desired to reduce the height so as not to hinder the flow of air from the air cooling fan. However, as described in Patent Documents 1 and 2, there is a problem that it is difficult to achieve a small size and a low profile with a structure in which a toroidal type or bobbin type coil is simply mounted on a wiring board.

  On the other hand, in the structure described in Patent Document 3, since the flat coil is formed, the coil itself can be easily reduced in height as compared with the structures described in Patent Documents 1 and 2. However, in this coil structure, although the coil itself can be reduced in height, there is a problem that when the coil is mounted and fixed on another circuit board, the overall height cannot be reduced sufficiently. That is, in order to mount the coil on another circuit board, a new fixing member for sandwiching the coil and the circuit board from the thickness direction is required, and as a result, the height cannot be reduced sufficiently.

The present invention has been made in view of such problems, and a first object thereof is a coil that can be fixed to a substrate with a simple configuration and can be reduced in size and height as a whole while being fixed to the substrate. Is to provide.
A second object of the present invention is to provide a line filter that can fix a coil to a substrate with a simple configuration and can be reduced in size and height as a whole while the coil is fixed to the substrate.

  The coil according to the present invention includes a substrate provided with a plurality of first through holes, a plurality of second through holes provided at positions corresponding to the plurality of first through holes, and one surface of the substrate. An attached plate-like core, and a coil conductor that is inserted into each first through hole and each second through hole, wound around the core so as to fix the core to the substrate, and forms a coil with the core; It is equipped with.

  The line filter according to the present invention is an LC filter type line filter including at least a coil and a capacitor, and includes a substrate provided with a plurality of first through holes, and a circuit component formed on the substrate and including at least the capacitor. And a plurality of second through holes provided at positions corresponding to the plurality of first through holes, a plate-like core attached to one surface of the substrate, each first through hole, and each first And a coil conductor that is wound around the core so as to fix the core to the substrate and forms a coil with the core.

  In the coil and line filter according to the present invention, the coil conductor is inserted into each first through hole and each second through hole, for example, and a plurality of conductors fixed to the substrate so that the core is fixed to the substrate. It can be composed of a pin and a coil wiring pattern formed of a conductor that connects predetermined conductor pins to each other.

  In this case, the substrate is provided with a plurality of sets of two through holes in parallel as a plurality of first through holes, and the core corresponds to the first through holes as a plurality of second through holes. A plurality of sets of two through-holes may be provided in parallel at the position to be. Each conductor pin is formed in a U-shape, is inserted into a set of through holes from the core side, and is fixed to the substrate on the other surface side of the substrate, and the coil wiring pattern is formed between adjacent through holes. A pattern may be formed so as to connect the conductor pins inserted into the set.

  Further, in the coil and the line filter according to the present invention, the coil conductor is constituted by a coil wire, and the coil wire is connected to the core and the substrate via each first through hole and each second through hole. It is also possible to adopt a configuration in which the wire is integrally wound with the wire.

  In the line filter according to the present invention, the coil conductor includes first and second coil conductors forming the first and second windings, and the first and second coil conductors, the core, A common mode choke coil may be formed. In this case, the circuit component includes first and second capacitors and an inductance element, and one end of the first capacitor is connected in the middle of the first winding formed by the first coil conductor. In addition, one end of the second capacitor is connected to the middle of the second winding formed by the second coil conductor, and the other ends of the first and second capacitors are grounded via the inductance element. May be.

  In the coil and line filter according to the present invention, a plurality of first through holes are provided in the substrate, and a plurality of second through holes are provided at positions corresponding to the plurality of first through holes in the plate-like core. And the core is attached to one side of the substrate. And the coil conductor which forms a coil with a core is inserted in each 1st through-hole and each 2nd through-hole, and it is wound around a core so that a core may be fixed to a board | substrate. With the basic structure as described above, the coil is fixed to the substrate with a simple configuration, and the overall size and height can be reduced with the coil fixed to the substrate.

  In particular, in the line filter according to the present invention, the coil conductor includes first and second coil conductors forming the first and second windings, and the first and second coil conductors and the core. When a common mode choke coil is formed at the same time, one end of the first and second capacitors is connected in the middle of the first and second windings, and the other end is grounded via an inductance element Compared to the conventional circuit configuration of a simple LC filter type line filter in which a capacitor is connected to the input / output terminal of the common mode choke coil, for example, a filter circuit excellent in reducing common mode noise can be realized. Become.

  According to the coil of the present invention, a substrate provided with a plurality of first through holes, a plurality of second through holes provided at positions corresponding to the plurality of first through holes, and one of the substrates For a coil that is inserted into a plate-like core attached to a surface, wound around each core through the first through-holes and second through-holes and wound around the core so as to fix the core to the substrate, and forms a coil together with the core Since it is provided with a conductor, it can be fixed to the substrate with a simple configuration, and it can be reduced in size and height as a whole while being fixed to the substrate.

  According to the line filter of the present invention, a substrate provided with a plurality of first through holes, a circuit component formed on the substrate and including at least a capacitor, and a plurality at positions corresponding to the plurality of first through holes. The second through-hole is provided, and is inserted into the plate-like core attached to one surface of the substrate, each first through-hole and each second through-hole, so as to fix the core to the substrate. And a coil conductor that forms a coil together with the core, so that the coil can be fixed to the substrate with a simple configuration, and the overall size is small and low with the coil fixed to the substrate. Can be achieved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The line filter according to the present embodiment includes the coil of the present invention. The line filter according to the present embodiment is connected to a power supply line, a signal line, and the like, and is used as a means for reducing ripple voltage and noise generated by a power conversion circuit, for example. It can also be used as means for reducing noise on the power line in power line communication or preventing communication signals on the indoor power line from leaking to the outdoor power line.

  FIG. 1 shows the overall configuration of the line filter, and FIG. 2 shows a cross section of the main part of the line filter. FIG. 3 shows an equivalent circuit of this line filter. The line filter includes a flat substrate 10, a circuit component formed on and mounted on the substrate 10, a core 20 made of a magnetic material, and a first and a second forming a common mode choke coil together with the core 20. Coil conductors 31 and 32. The core 20 is formed in a flat plate shape (formed in a rectangular flat plate shape in the example of FIG. 1), and is attached to, for example, a central portion on one surface (front surface) of the substrate 10.

  Each of the substrate 10 and the core 20 is provided with a plurality of through holes. More specifically, a plurality of sets of two through-holes 11A and 11B (FIG. 2) are provided in parallel as the first through-hole in the portion to which the core 20 of the substrate 10 is attached. The core 20 is also provided with a plurality of sets of two through holes 21A and 21B in parallel as second through holes at positions corresponding to the first through holes 11A and 11B.

  The first and second coil conductors 31 and 32 are inserted into the first through holes 11A and 11B and the second through holes 21A and 21B, respectively, so that the core 20 is fixed to the substrate 10. A coil is formed together with the core 20.

  More specifically, the first coil conductor 31 includes a plurality of conductor pins 31A and a coil wiring pattern 31B made of a conductor that connects the predetermined conductor pins 31A. Each conductor pin 31A is formed, for example, in a U shape as shown in FIG. 2, and is inserted from the core 20 side into each of the second through holes 21A and 21B and each of the first through holes 11A and 11B. . Then, the two tip portions of each conductor pin 31 </ b> A are soldered by the solder 33 on the other surface (back surface) side of the substrate 10 and fixed to the substrate 10. Thereby, the core 20 is fixed to the substrate 10. The coil wiring pattern 31B is formed on the back surface side of the substrate 10 and is patterned so as to connect the conductor pins 31A inserted through the sets of adjacent through holes. More specifically, the pattern is formed so that one tip of one adjacent conductor pin 31A is connected to the tip on the opposite side of the other conductor pin 31A. The coil wiring pattern 31B is electrically connected to the conductor pin 31A by the solder 33.

  In this way, the plurality of conductor pins 31A are continuously connected to the coil wiring pattern 31B, so that one first coil conductor 31 is formed as a whole, and one winding of the common mode choke coil is formed as a whole. A line is formed. Here, when each conductor pin 31A has the same shape and the coil wiring pattern 31B is illustrated, the illustrated intermediate connection portion P1 is included in one of the windings formed by the first coil conductor 31. This is the point position. In this case, the first inductor L1 in the equivalent circuit of FIG. 3 includes, for example, the first coil conductor 31 and the core 20 from the left end of FIG. 1 to the intermediate connection portion P1 with the intermediate connection portion P1 as a boundary. The second inductor L2 is formed by the first coil conductor 31 and the core 20 from the intermediate connection portion P1 to the right end of FIG. In this case, the inductances of the first and second inductors L1 and L2 have the same value.

  Similarly, the second coil conductor 32 includes a plurality of conductor pins 32A and a coil wiring pattern 32B. The plurality of conductor pins 32A are continuously connected to the coil wiring pattern 32B, so that one second coil conductor 32 is formed as a whole, and the other winding of the common mode choke coil is formed as a whole. ing. In the illustrated example, the conductor pin 31A for the first coil conductor 31 and the conductor pin 32A for the second coil conductor 32 are inserted into the same through hole. However, the conductor pin 31A and the conductor By covering the pin 32A with an insulator, it is possible to prevent a short circuit between the two conductor pins.

  Here, when each conductor pin 32A has the same shape and the coil wiring pattern 32B is illustrated, the illustrated intermediate connection portion P3 is included in the other winding formed by the second coil conductor 32. This is the point position. In this case, the third inductor L3 in the equivalent circuit of FIG. 3 includes the second coil conductor 32 and the core 20 from the left end of FIG. 1 to the intermediate connection portion P3, for example, with the intermediate connection portion P3 as a boundary. The fourth inductor L4 is formed by the second coil conductor 32 and the core 20 from the intermediate connection portion P3 to the right end of FIG. In this case, the inductances of the third and fourth inductors L3 and L4 have the same value.

  The connection positions of the conductor pins 31A and 32A and the formation positions (formation patterns) of the coil wiring patterns 31B and 32B are not limited to those shown in FIG. 1, and other forms can be adopted.

  The substrate 10 is provided with a pair of input terminals 1A and 1B, a pair of output terminals 2A and 2B, and a ground terminal 5. These terminals are formed by through holes whose inner surfaces are metallized, for example. The pair of input terminals 1 </ b> A and 1 </ b> B are arranged at predetermined intervals along the first side of the substrate 10. The ground terminal 5 is disposed between the pair of input terminals 1A and 1B. A ground pattern 55 made of a conductor is formed around the ground terminal 5. On the other hand, the pair of output terminals 2 </ b> A and 2 </ b> B are arranged at a predetermined interval along a second side that faces the first side of the substrate 10.

  On the surface of the substrate 10, first and second capacitors C1 and C2 and an inductance element (fifth inductor L5) are mounted as circuit components (chip components). The first and second capacitors C1 and C2 are mounted in empty areas along the third and fourth sides of the substrate 10 so as to substantially face each other with the core 20 interposed therebetween, and the fifth inductor L5 is Similarly, it is disposed in the empty area of the substrate 10 and in the vicinity of the ground terminal 5. That is, these circuit components are mounted on the same surface of the same substrate. The first and second capacitors C1 and C2 are symmetrically arranged. The fifth inductor L5 corresponds to a specific example of “inductance element” in the invention.

  Also on the substrate 10, wiring patterns 51A, 51B, 52A, 52B, 53A, 53B, and 54 are formed by conductors for connecting the respective circuit elements. The wiring patterns 51A, 51B, 52A, and 52B are formed on the back surface of the substrate 10, for example, and the wiring patterns 53A, 53B, and 54 are formed on the surface of the substrate 10, for example. However, any wiring pattern can be formed on the opposite surface, and the connection position with each circuit element may also be the opposite surface from the following description. In this case, when there is an object to be connected to the front surface and the back surface of the substrate 10, for example, the connection may be made using a through hole whose inner surface is metallized. The connection relationship of each circuit element is as follows.

  One input terminal 1A is connected to one end of a first coil conductor 31 via a wiring pattern 51A. Similarly, one end of the second coil conductor 32 is connected to the other input terminal 1B via a wiring pattern 51B. Further, the other end of the first coil conductor 31 is connected to one output terminal 2A via a wiring pattern 52A. Similarly, the other output terminal 2B is connected to the other end of the second coil conductor 32 via a wiring pattern 52B. The wiring patterns 51A, 51B, 52A, and 52B are patterned on the back surface of the substrate 10, for example, and connected to the ends of the first and second coil conductors 31 and 32 on the back surface side.

  One end of the first capacitor C1 is connected to the intermediate connection portion P1 of the first coil conductor 31 via the wiring pattern 53A on the surface of the substrate 10. Similarly, one end of the second capacitor C2 is connected to the intermediate connection portion P3 of the second coil conductor 32 via the wiring pattern 53B on the surface of the substrate 10.

  The other ends of the first and second capacitors C1, C2 are commonly connected to one end of the fifth inductor L5 via the wiring pattern 54 on the surface of the substrate 10. The other end of the fifth inductor L5 is commonly connected to the ground pattern 55 on the surface of the substrate 10 and is grounded. Thus, the other ends of the first and second capacitors C1 and C2 are grounded via the fifth inductor L5. As a result, the first and second intermediate connection portions P1, P3 are grounded via the circuit component.

  With the configuration as described above, the filter circuit shown by the equivalent circuit in FIG. 3 is realized. This filter circuit includes a pair of input terminals 1A and 1B, output terminals 2A and 2B, and a ground terminal 5. The filter circuit further includes first and second inductors L1 and L2 inserted in series between one input terminal 1A and one output terminal 2A. The filter circuit is further inserted in series between the other input terminal 1B and the other output terminal 2B, and cooperates with the first and second inductors L1 and L2 to suppress the common mode noise. And fourth inductors L3 and L4.

  The first and second inductors L1 and L2 are electromagnetically coupled to each other. Similarly, the third and fourth inductors L3 and L4 are electromagnetically coupled to each other. As described above, a connection point (intermediate connection portion P1) is provided in the middle of one winding formed by the first coil conductor 31, and the first winding extends from one end of the winding to the connection point. The first inductor L1 is formed as the line portion 31a, and similarly, the second inductor L2 is formed from the other end of the winding to the connection point as the second winding portion 31b. Similarly, for the third and fourth inductors L3 and L4, a connection point (intermediate connection portion P3) is provided in the middle of the other winding formed by the second coil conductor 32, and the other winding is connected. A third inductor L3 is formed with the third winding portion 32a from one end to the connection point, and a fourth winding portion 32b is formed from the other end of the other winding to the connection point. Four inductors L4 are formed. Here, it is preferable in terms of performance as a filter that the inductances of the first and second inductors L1 and L2 have the same value. The inductances of the third and fourth inductors L3 and L4 are preferably set to the same value. More preferably, all the inductances of the first and second inductors L1 and L2 and the third and fourth inductors L3 and L4 are set to the same value.

  Winding (first coil conductor 31) constituting the first and second inductors L1, L2, and winding (second coil conductor 32) constituting the third and fourth inductors L3, L4 Are wound around a common core 20 and are coupled together to cooperate and suppress common mode noise. That is, that is, these windings are wound around the core 20 in such a direction that magnetic fluxes induced in the core 20 are canceled by the currents flowing through the windings when a normal mode current flows through them. Thus, the windings and the core 20 constitute a common mode choke coil that suppresses common mode noise and allows a normal mode signal to pass.

  The filter circuit further includes a first capacitor C1 having one end connected to the intermediate connection portion P1, a second capacitor C2 having one end connected to the intermediate connection portion P3, and first and second capacitors C1 having one end connected to the intermediate connection portion P3. , C2 and a fifth inductor L5 connected to the ground terminal 5 at the other end.

  The first capacitor C1 and the fifth inductor L5 connected in series constitute a first series circuit having one end connected to the intermediate connection portion P1 and the other end grounded. Further, the second capacitor C2 and the fifth inductor L5 connected in series constitute a second series circuit in which one end is connected to the intermediate connection portion P3 and the other end is grounded. Thus, in this filter circuit, the fifth inductor L5 is shared by the first series circuit and the second series circuit.

  Next, operations and effects of the line filter according to the present embodiment will be described.

  First, the operation as a filter circuit shown by the equivalent circuit in FIG. 3 will be described. First, the case where the common mode voltage Vi is applied to the input terminals 1A and 1B will be described. In this case, one end of the first inductor L1 (the end opposite to the intermediate connection portion P1) and the ground, and one end of the third inductor L3 (the opposite side to the intermediate connection portion P3). An equal voltage Vi is generated between the end of the terminal and the ground. The voltage Vi generated between one end of the first inductor L1 and the ground is divided by the first inductor L1 and the first series circuit (the first capacitor C1 and the fifth inductor L5), Predetermined voltages are generated between both ends of the first inductor L1 and between both ends of the first series circuit. Note that the arrow in the figure indicates that the potential ahead is higher. Similarly, the voltage Vi generated between one end of the third inductor L3 and the ground is divided by the third inductor L3 and the second series circuit (the second capacitor C2 and the fifth inductor L5). And a predetermined voltage is generated between both ends of the third inductor L3 and between both ends of the second series circuit. Since the first inductor L1 and the second inductor L2 are electromagnetically coupled to each other, a predetermined voltage is generated between both ends of the second inductor L2 according to the voltage generated between both ends of the first inductor L1. Will occur. The voltage between the other end of the second inductor L2 (the end opposite to the intermediate connection portion P1) and the ground, that is, the voltage Vo between the terminal 2A and the ground is a voltage generated in the second inductor L2. Although expressed as the sum of the voltages generated in the first series circuit, these voltages cancel each other because they are in opposite directions, and as a result, are generated between one end of the first inductor L1 and the ground. That is, the voltage Vi generated between the terminal 1A and the ground.

  Similarly, since the third inductor L3 and the fourth inductor L4 are electromagnetically coupled to each other, according to the voltage generated between both ends of the third inductor L3, between the both ends of the fourth inductor L4. A predetermined voltage is generated. As a result, the voltage between the other end of the fourth inductor L4 (the end opposite to the intermediate connection portion P3) and the ground, that is, the voltage Vo between the terminal 2B and the ground is equal to one of the third inductor L3. Is smaller than a voltage generated between the end of the terminal and the ground, that is, a voltage Vi generated between the terminal 1B and the ground. In this way, when the common mode voltage is applied to the input terminals 1A and 1B, the common mode voltage generated at the output terminals 2A and 2B is the common mode voltage applied to the input terminals 1A and 1B. Smaller than.

  Also, in this filter circuit, when a common mode voltage is applied to the output terminals 2A and 2B, the common mode voltage generated at the input terminals 1A and 1B is the same as that described above. It becomes smaller than the common mode voltage applied to 2B. As described above, according to this filter circuit, the common mode noise is applied to both the case where the common mode noise is applied to the input terminals 1A and 1B and the case where the common mode noise is applied to the output terminals 2A and 2B. Noise can be suppressed.

  According to this filter circuit, common mode noise can be effectively suppressed in a wide frequency range with a relatively simple configuration and without using a coil having a large inductance.

  Next, the structural advantages and effects of this line filter will be described. In this line filter, a plurality of first through holes 11A and 11B are provided in the substrate 10, and a plurality of second through holes are provided at positions corresponding to the plurality of first through holes 11A and 11B in the plate-like core 20. Through holes 21 </ b> A and 21 </ b> B are provided, and the core 20 is attached to one surface of the substrate 10. The first and second coil conductors 31 and 32 that form a common mode choke coil together with the core 20 are inserted into the first through holes 11A and 11B and the second through holes 21A and 21B. The core 20 is wound around the core 20 so as to be fixed to the substrate 10. In addition, each circuit component is mounted in an empty area of the substrate 10. With the basic structure as described above, the coil can be fixed to the substrate 10 with a simple configuration, and the overall size and height can be reduced with the coil fixed to the substrate 10. In particular, since the first and second coil conductors 31 and 32 also serve as a fixing member, it is not necessary to newly provide a mounting fixing member. Further, when the core 20 is mounted on the substrate 10, the positioning can be performed by the through holes provided in each of the cores 20, and the positioning becomes easy.

  Further, a connection point (intermediate connection portion P1) is provided in the middle of one of the windings formed by the first coil conductor 31, and the connection point is connected to one end of the first capacitor C1, and the second A connection point (intermediate connection portion P3) is provided in the middle of the other winding formed by the coil conductor 32, the connection point is connected to one end of the second capacitor C2, and further the first and second capacitors C1. , C2 is grounded via an inductance element (fifth inductor L5), the filter circuit shown in FIG. 3 can be realized. Thereby, for example, a filter circuit excellent in reducing common mode noise can be realized as compared with a circuit configuration of a conventional simple LC filter type line filter in which a capacitor is connected to an input / output terminal of a common mode choke coil.

  Further, by optimizing the arrangement of the terminals such as the input terminals 1A and 1B and the circuit components such as the first and second capacitors C1 and C2, the empty areas of the respective boards are efficiently used. However, the coupling between the respective parts is suppressed, and deterioration of characteristics can be prevented. In particular, with the illustrated arrangement, the wiring distance between the first and second capacitors C1 and C2, the fifth inductor L5, and the ground terminal 5 can be shortened, thereby preventing characteristic deterioration.

[Modification]
4 and 5 show a first modification of the line filter according to the present embodiment. In addition, the same code | symbol is attached | subjected to the component substantially the same as the line filter of FIG. 1 and FIG. 2, and description is abbreviate | omitted suitably. In the line filter of FIGS. 1 and 2, the first and second coil conductors 31 and 32 are composed of the conductor pins 31A and 32A and the coil wiring patterns 31B and 32B. First and second coil conductors 131 and 132 made of wire are provided. Further, the wiring patterns 51A, 51B, 52A, and 52B are formed on the surface of the substrate 10 instead of the back surface. However, as in the case of the line filter of FIGS. 1 and 2, any wiring pattern can be formed on the opposite surface.

  The first and second coil conductors 131 and 132 are inserted into the first through holes 11A and 11B and the second through holes 21A and 21B, respectively. As shown in FIG. The core 20 and the substrate 10 are integrally wound so as to be fixed, and a common mode choke coil is formed together with the core 20. FIG. 5 conceptually illustrates how the conductor is wound, and shows a simplified cross-sectional structure. FIG. 5 shows a cross-sectional configuration viewed from the left side of FIG. 4, and conceptually shows how to wind one wire 131 </ b> A of the first coil conductor 131.

  More specifically, the first coil conductor 131 includes two wires 131A and 131B. One end of one wire 131A is connected to one input terminal 1A via a wiring pattern 51A on the surface of the substrate 10. One end of the other wire 131B is connected to one output terminal 2A via a wiring pattern 52A on the surface of the substrate 10. The other ends of the wires 131A and 131B are commonly connected to one end of the first capacitor C1 via the wiring pattern 53A.

  In the commonly connected portion, the wire members 131A and 131B are continuously connected, so that one first coil conductor 131 is formed as a whole, and one winding of the common mode choke coil is formed as a whole. A line is formed. Here, in the illustrated form, the wires 131A and 131B are wound so as to have the same length, and the portion connected in common becomes the intermediate connection portion P1, which is formed by the first coil conductor 131. The middle point position of the winding. In this case, the first inductor L1 in the equivalent circuit of FIG. 3 is formed by the one wire 131A and the core 20 with the intermediate connection portion P1 as a boundary, and the second inductor L2 is formed by the other wire 131B and the core 20 Is formed. In this case, the inductances of the first and second inductors L1 and L2 have the same value.

  Similarly, the second coil conductor 132 is composed of two wires 132A and 132B. One end of one wire 131A is connected to the other input terminal 1B via the wiring pattern 51B on the surface of the substrate 10. One end of the other wire 132B is connected to the other output terminal 2B via the wiring pattern 52B on the surface of the substrate 10. The other ends of the wires 132A and 132B are commonly connected to one end of the second capacitor C2 via the wiring pattern 53B.

  In this commonly connected portion, the respective wire rods 132A and 132B are continuously connected, so that one second coil conductor 132 is formed as a whole, and the other winding of the common mode choke coil as a whole. A line is formed. Here, in the illustrated form, the wires 132A and 132B are wound so as to have the same length, and the portion connected in common becomes the intermediate connection portion P3, and the other formed by the second coil conductor 132. The middle point position of the winding. In this case, the third inductor L3 in the equivalent circuit of FIG. 3 is formed by one wire 132A and the core 20 with the intermediate connection portion P3 as a boundary, and the fourth inductor L4 is formed by the other wire 132B and the core 20. Is formed. In this case, the inductances of the third and fourth inductors L3 and L4 have the same value.

  In addition, about the winding method of the 1st and 2nd coil conductors 131 and 132, and the connection method to another circuit element, it is not limited to what was shown in FIG. 4, Other forms can be taken. In FIG. 4, the first and second coil conductors 131 and 132 are each composed of two wires, but each may be composed of only one wire. Moreover, you may be comprised with the 3 or more wire rod, respectively.

  FIG. 6 shows a second modification. FIG. 7 is an equivalent circuit of the line filter according to the second modification. The line filter according to the present invention is not limited to the filter circuit shown in FIG. 3, and can be applied to all LC filters including at least a coil (inductor) and a capacitor. For example, as shown in FIG. 7, the present invention can also be applied to an LC filter circuit including only one inductor L11 and one capacitor C11. The inductor L11 is inserted in series on the conductive lines 151 and 152 between the one input terminal 1A and the one output terminal 2A. One end of the capacitor C11 is connected to the other end of the inductor L11 via the conductive line 152 on the one output terminal 2A side, and the other end is connected to the conductive line 153 between the other input terminal 1B and the other output terminal 2B. It is connected.

  The line filter according to this modification includes the substrate 10 provided with the first through holes 11A and 11B and the core 20 provided with the second through holes 21A and 21B, as in the configuration example of FIGS. And. The line filter also includes one coil conductor 231 that forms a coil with the core 20.

  More specifically, the coil conductor 231 includes a plurality of conductor pins 231A and a coil wiring pattern 231B made of a conductor connecting adjacent conductor pins 231A. As in the configuration example of FIGS. 1 and 2, a plurality of conductor pins 231A are continuously connected via the coil wiring pattern 231B, so that one coil conductor 231 is formed as a whole. A winding is formed. The coil conductor 231 and the core 20 form an inductor L11 in the equivalent circuit of FIG.

  A capacitor C11 in the equivalent circuit of FIG. 7 is mounted on the surface of the substrate 10 as a circuit component (chip component). On the surface of the substrate 10, a wiring pattern is formed by conductors corresponding to the conductive lines 151, 152, and 153 in the equivalent circuit of FIG. 7. Each wiring pattern is connected to each circuit element so as to correspond to the equivalent circuit of FIG. Thereby, the equivalent circuit of FIG. 7 is realized.

  As in the case of the line filter of FIGS. 1 and 2, any wiring pattern can be formed on the opposite surface. Also in the modified example of FIG. 6, the coil conductor 231 can also be configured by a coil wire, similarly to the configuration example of FIG. 4.

  In addition, this invention is not limited to the said embodiment and modification, A various change is possible. For example, in the configuration example of FIG. 1, other circuit components may be mounted on the substrate 10. For example, in the equivalent circuit of FIG. 3, if other circuit elements (capacitors and resistance elements) are connected in parallel to the fifth inductor L5, better filter characteristics can be obtained. Such a circuit element may be further mounted.

  Further, for example, in the configuration example of FIG. 1, the first and second coil conductors 31 and 32 are inserted into the same first through holes 11A and 11B and the second through holes 21A and 21B and shared. However, the first and second coil conductors 31 and 32 may be inserted into separate through holes without sharing the through holes. The same applies to the configuration example of FIG. In the configuration example of FIG. 1, the coil wiring patterns 31 </ b> B and 32 </ b> B may be formed on the front side instead of the back side of the substrate.

It is a top view which shows one structural example of the line filter which concerns on one embodiment of this invention. It is a fragmentary sectional view showing an example of 1 composition of a line filter concerning a 1 embodiment of the present invention. It is a circuit diagram which shows the equivalent circuit of the line filter which concerns on one embodiment of this invention. It is a top view which shows the 1st modification of the line filter which concerns on one embodiment of this invention. It is a fragmentary sectional view showing the 1st modification of a line filter concerning one embodiment of the present invention. It is a top view which shows the 2nd modification of the line filter which concerns on one embodiment of this invention. It is a circuit diagram which shows the equivalent circuit of the line filter which concerns on a 2nd modification.

Explanation of symbols

  C1 ... first capacitor, C2 ... second capacitor, C3 ... third capacitor, L1 ... first inductor, L2 ... second inductor, L3 ... third inductor, L4 ... fourth inductor, L5 ... 5th inductor (inductance element), 1A, 1B ... input terminal, 2A, 2B ... output terminal, 5 ... ground terminal, 10 ... substrate, 11A, 11B ... first conduction hole, 20 ... core, 21A, 21B ... 2nd conduction hole, 31 ... 1st coil conductor (1st coil | winding), 31A ... 1st conductor pin, 31B ... 1st coil wiring pattern, 32 ... 2nd coil conductor ( (Second winding), 32A ... second conductor pin, 32B ... second coil wiring pattern, 51A, 51B, 52A, 52B, 53A, 53B, 54 ... wiring pattern.

Claims (9)

A substrate provided with a plurality of first through holes;
A plurality of second through holes are provided at positions corresponding to the plurality of first through holes, and a plate-like core attached to one surface of the substrate;
A coil conductor inserted through each of the first through holes and each of the second through holes, wound around the core so as to fix the core to the substrate, and forming a coil together with the core. A coil characterized by that. The coil conductor is
A plurality of conductor pins that are inserted through the first through holes and the second through holes, and are fixed to the substrate so that the core is fixed to the substrate;
The coil according to claim 1, comprising: a coil wiring pattern formed of a conductor formed on the substrate and connecting predetermined conductor pins. The substrate is provided with a plurality of sets of two through holes in parallel as the plurality of first through holes,
In the core, a plurality of sets of two through holes are provided in parallel at positions corresponding to the first through holes as the plurality of second through holes,
Each of the conductor pins is formed in a U shape, is inserted into the set of through holes from the core side, and is fixed to the substrate on the other surface side of the substrate,
The coil according to claim 2, wherein the coil wiring pattern is formed so as to connect the conductor pins inserted through the set of adjacent through holes. The coil conductor is composed of a coil wire,
2. The coil wire according to claim 1, wherein the coil wire is integrally wound around the core and the substrate via the first through holes and the second through holes. coil. An LC filter type line filter including at least a coil and a capacitor,
A substrate provided with a plurality of first through holes;
A circuit component formed on the substrate and including at least a capacitor;
A plurality of second through holes are provided at positions corresponding to the plurality of first through holes, and a plate-like core attached to one surface of the substrate;
A coil conductor inserted through each of the first through holes and each of the second through holes, wound around the core so as to fix the core to the substrate, and forming a coil together with the core. A line filter characterized by that. The coil conductor is
A plurality of conductor pins that are inserted through the first through holes and the second through holes, and are fixed to the substrate so that the core is fixed to the substrate;
The line filter according to claim 5, comprising: a coil wiring pattern formed of a conductor formed on the substrate and connecting predetermined conductor pins. The substrate is provided with a plurality of sets of two through holes in parallel as the plurality of first through holes,
In the core, a plurality of sets of two through holes are provided in parallel at positions corresponding to the first through holes as the plurality of second through holes,
Each of the conductor pins is formed in a U shape, is inserted into the set of through holes from the core side, and is fixed to the substrate on the other surface side of the substrate,
The line filter according to claim 6, wherein the coil wiring pattern is formed in a pattern so as to connect conductor pins inserted through the set of adjacent through holes. The coil conductor is composed of a coil wire,
The coil wire is wound integrally around the core and the substrate via the first through holes and the second through holes, respectively. Line filter. The coil conductor has first and second coil conductors forming first and second windings, and a common mode choke coil is formed by the first and second coil conductors and the core. Formed,
The circuit component includes first and second capacitors, and an inductance element,
One end of the first capacitor is connected to the middle of the first winding formed by the first coil conductor, and one end of the second capacitor is formed by the second coil conductor. The second winding is connected in the middle of the second winding, and the other ends of the first and second capacitors are grounded via the inductance element. The line filter described in the paragraph.

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