Common-mode filter

Abstract

This invention relates to a common-mode filter. High-frequency characteristics are further improved in a common-mode filter where a pair of wires cross midway. The filter includes wires (W1, W2) wound in the same direction around a core portion (23). The wires (W1, W2) form three winding blocks (B1 to B3), and cross each other in the region between winding blocks (B1) and (B3), and in the region between winding blocks (B2) and (B3). According to the invention, the number of winding blocks is odd; therefore, if the wires (W1) and (W2) cross an even number of times between axially adjacent winding blocks, the positional relationship of one end of the wires (W1, W2) can be made consistent with the positional relationship of the other end. Thus, since the conditions of one end of the wires (W1, W2) are consistent with the other end, high-frequency characteristics such as reflection characteristics (return loss) and noise conversion characteristics can be improved.

Description

[0001] This application was filed on [date]. January 4, 2019 Application number is 201910007285.4 The invention is named Common mode filter Waveformer A divisional application of the patent application. Technical Field

[0002] This invention relates to a common-mode filter, and more particularly to a common-mode filter of the type in which a pair of wires cross midway, and a method for manufacturing the same. Background Technology

[0003] Common-mode filters, used to remove common-mode noise that overlaps with differential signal lines, are widely used in many electronic devices such as portable electronic devices and automotive LANs. In recent years, common-mode filters using drum-shaped magnetic cores that can be surface-mounted have replaced those using toroidal magnetic cores (see Patent Document 1).

[0004] The common-mode filter described in Patent Document 1 improves the symmetry of differential signals in the high-frequency region by causing a pair of wires to cross midway.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2014-199904 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, when the wires cross midway, the positional relationship of a pair of wires is reversed. Therefore, in order to restore the original positional relationship, the wires need to cross again. Moreover, when this second crossing is performed near the end of the wires, a difference is created where a pair of wires cross at one end and a pair of wires do not cross at the other end. This has been determined to be the cause of the deterioration of high-frequency characteristics such as reflection characteristics (return loss) and noise conversion characteristics.

[0010] Therefore, the object of the present invention is to further improve the high-frequency characteristics in a common-mode filter in which a pair of wires cross midway.

[0011] Technical solutions for solving the problem

[0012] The common-mode filter according to the present invention is characterized by comprising: a core portion; and first and second wires wound in the core portion along the same direction, the first and second wires constituting a first winding block with multiple turns wound at one end of the core portion along its axial direction, a second winding block with multiple turns wound at the other end of the core portion along its axial direction, and a third winding block located between the first winding block and the second winding block and constituting an odd number of winding blocks with multiple turns wound, the second winding block being the odd-numbered winding block counted from the first winding block, the first wire and the second wire intersecting each other in the region between the first winding block and the third winding block, and intersecting each other in the region between the second winding block and the third winding block.

[0013] According to the present invention, the number of winding blocks is odd. Therefore, if the first and second conductors are crossed an even number of times between adjacent winding blocks in the axial direction, the positional relationship of one end of the first and second conductors can be made consistent with the positional relationship of the other end. As a result, the conditions of one end of the first and second conductors and the other end are consistent, thereby improving high-frequency characteristics such as reflection characteristics (return loss) and noise conversion characteristics.

[0014] In this invention, the number of turns of the first winding block and the number of turns of the second winding block can also be equal. This increases the symmetry of the first and second winding blocks at both ends, thus eliminating the product's directionality.

[0015] In this invention, the total number of turns of the first and second winding blocks and the number of turns of the third winding block can also be equal. Therefore, considering the same turn of the first and second conductors, the number of pairs of the first conductor located at one end of the winding core along the axial direction is the same as the number of pairs of the second conductor located at one end of the winding core along the axial direction. Thus, the symmetry between the signal flowing through the first conductor and the signal flowing through the second conductor becomes higher, resulting in excellent high-frequency characteristics.

[0016] In this invention, the first, second, and third winding blocks may also have a first winding layer located at the bottom and a second winding layer located above the first winding layer. This increases the winding density of the wire, thus allowing for a reduction in the axial dimensions of the core portion.

[0017] In this invention, in any of the first, second, and third winding blocks, the first wire may be located in the first winding layer, and the second wire may be located in the second winding layer. Therefore, it can be manufactured by sequentially winding the first and second wires. Alternatively, in the first and second winding blocks, the first wire may be located in the first winding layer, and the second wire in the second winding layer; in the third winding block, the first wire may be located in the second winding layer, and the second wire in the first winding layer. This reduces the difference in length between the first and second wires.

[0018] In this invention, the third winding block may also include a fourth, fifth, and sixth winding block arranged sequentially when viewed from the first winding block. The first wire and the second wire intersect each other in the region between the first and fourth winding blocks, in the region between the fourth and fifth winding blocks, in the region between the fifth and sixth winding blocks, and in the region between the sixth winding block and the second winding block. Thus, the first wire and the second wire can intersect four times.

[0019] In this invention, the number of turns of the first winding block and the number of turns of the fifth winding block can also be equal. This improves the symmetry of the first and fifth winding blocks located at odd-numbered positions.

[0020] In this invention, the number of turns of the fourth winding block and the number of turns of the sixth winding block can also be equal. This improves the symmetry of the even-numbered fourth and sixth winding blocks.

[0021] In this invention, the total number of turns of the first, second, and fifth winding blocks can also be equal to the number of turns of the fourth and sixth winding blocks. This increases the symmetry between the signal flowing through the first conductor and the signal flowing through the second conductor, thus resulting in excellent high-frequency characteristics.

[0022] In this invention, counting from the first winding block, the number of turns of each odd-numbered winding block can be less than the number of turns of each even-numbered winding block. This reduces the difference between the total number of turns of the odd-numbered winding blocks and the total number of turns of the even-numbered winding blocks.

[0023] The effects of the invention

[0024] Thus, according to the present invention, the high-frequency characteristics of a common-mode filter that causes a pair of wires to cross midway can be improved. Attached Figure Description

[0025] Figure 1 This is a general perspective view showing the appearance of the common-mode filter 10 according to a preferred embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram used to illustrate in more detail the winding layout of the first and second conductors W1 and W2;

[0027] Figure 3 This is a schematic diagram used to explain why the first conductor W1 and the second conductor W2 do not cross on the 24th turn;

[0028] Figure 4 This is a schematic diagram illustrating the situation where the first conductor W1 and the second conductor W2 of the common-mode filter in the comparative example cross at the final turn;

[0029] Figure 5This is another schematic diagram illustrating the case where the first conductor W1 and the second conductor W2 of the common-mode filter in the comparative example cross at the final turn;

[0030] Figure 6 This is another schematic diagram illustrating the situation where the first conductor W1 and the second conductor W2 of the common-mode filter in the comparative example cross at the final turn;

[0031] Figure 7 This is a schematic diagram illustrating the winding layout of the common-mode filter 10A in the first modified example;

[0032] Figure 8 This is a schematic diagram illustrating the winding layout of the common-mode filter 10B in the second modified example;

[0033] Figure 9 This is a schematic diagram illustrating the winding layout of the common-mode filter 10C in the third modified example.

[0034] Explanation of symbols:

[0035] 10. 10A~10C Common-mode Filters

[0036] 20 Drum-shaped magnetic core

[0037] 21 First flange portion

[0038] 22 Second flange portion

[0039] 21b, 22b mounting surfaces

[0040] 21s, 22s outer side

[0041] 21t, 22t upper surface

[0042] 23. Core section

[0043] 30 Plate-shaped magnetic core

[0044] 41 First terminal electrode

[0045] 42 Second terminal electrode

[0046] 43 Third terminal electrode

[0047] 44 Fourth terminal electrode

[0048] A1 First winding area

[0049] A2 Second winding area

[0050] A3 Third winding area

[0051] A4 Fourth winding area

[0052] A5 Fifth winding area

[0053] A6 Sixth Roll Wrapping Area

[0054] B1 First winding block

[0055] B2 Second Winding Block

[0056] B3 Third Roll Wrap

[0057] B4 Fourth Roll Wrap

[0058] B5 Fifth Roll Winding Block

[0059] B6 Sixth Roll Wrap

[0060] CA1 First Intersection Area

[0061] CA2 Second Intersection Area

[0062] CA3 Third Intersection Area

[0063] CA4 Fourth Intersection

[0064] S1 First winding layer

[0065] S2 Second Wrapping Layer

[0066] W1 First Conductor

[0067] W2 Second Conductor Detailed Implementation

[0068] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0069] Figure 1 This is a general perspective view showing the appearance of the common-mode filter 10 according to a preferred embodiment of the present invention.

[0070] like Figure 1 As shown, the common-mode filter 10 of this embodiment includes: a drum-shaped magnetic core 20, a plate-shaped magnetic core 30, first to fourth terminal electrodes 41 to 44, and first and second conductive wires W1 and W2. The drum-shaped magnetic core 20 and the plate-shaped magnetic core 30 are made of magnetic materials with high permeability, such as Ni-Zn ferrite. Furthermore, the first to fourth terminal electrodes 41 to 44 are metal parts made of good conductors such as copper. The first to fourth terminal electrodes 41 to 44 may also be made by directly soldering silver paste or the like onto the drum-shaped magnetic core 20.

[0071] The drum-shaped magnetic core 20 has a first flange portion 21, a second flange portion 22, and a core portion 23 disposed between them. The core portion 23 has a structure in which the x-direction is defined as the axial direction, and the first and second flange portions 21 and 22 are respectively disposed at both ends, and they are integrally formed. A plate-shaped magnetic core 30 is bonded to the upper surfaces 21t and 22t of the flange portions 21 and 22. The upper surfaces 21t and 22t of the flange portions 21 and 22 form an xy plane, and their opposite sides are used as mounting surfaces 21b and 22b. Furthermore, the first and second terminal electrodes 41 and 42 are disposed on the mounting surface 21b and the outer surface 21s of the first flange portion 21, and the third and fourth terminal electrodes 43 and 44 are disposed on the mounting surface 22b and the outer surface 22s of the second flange portion 22. The outer surfaces 21s and 22s form a yz plane. The first to fourth terminal electrodes 41 to 44 are fixed by adhesive or the like.

[0072] The first and second wires W1 and W2 are wound in the same direction on the core portion 23. Moreover, one end of the first wire W1 is connected to the first and third terminal electrodes 41 and 43, respectively, and one end of the second wire W2 is connected to the second and fourth terminal electrodes 42 and 44, respectively. The first and second wires W1 and W2 have the same number of turns.

[0073] like Figure 1 As shown, the core portion 23 of the drum-shaped magnetic core 20 includes: a first winding region A1 closest to the first flange portion 21, a second winding region A2 closest to the second flange portion 22, and a third winding region A3 located between the first winding region A1 and the second winding region A2. Furthermore, the region between the first winding region A1 and the third winding region A3 constitutes a first crossing region CA1, and the region between the second winding region A2 and the third winding region A3 constitutes a second crossing region CA2. Moreover, the first and second conductors W1 and W2 are arranged and wound in the first to third winding regions A1 to A3, and cross each other in the first and second crossing regions CA1 and CA2. When the first and second conductors W1 and W2 cross, their positional relationship changes before and after the crossing.

[0074] Figure 2 This is a schematic diagram used to illustrate in more detail the winding layout of the first and second conductors W1 and W2.

[0075] like Figure 2 As shown, the first and second conductors W1 and W2 constitute a first winding block B1 wound in the first winding region A1, a second winding block B2 wound in the second winding region A2, and a third winding block B3 wound in the third winding region A3. As described above, they intersect each other in the first and second intersection regions CA1 and CA2. Figure 2In the example shown, the first and second winding blocks B1 and B2 each have 6 turns, and the third winding block B3 has 12 turns. Thus, the first and second conductors W1 and W2 each have a 24-turn structure consisting of the 1st to the 24th turns, but the present invention is not limited to this.

[0076] The first to third winding blocks B1 to B3 each have a double-layer structure. That is, they have: a first winding layer S1 located at the bottom and directly wound on the core portion 23; and a second winding layer S2 located above the first winding layer S1 and wound on the core portion 23 via the first winding layer S1. Moreover, the first conductor W1 is located in the first winding layer S1, and most of the second conductor W2 is located in the second winding layer S2. However, the 6th, 8th, and 24th turns of the second conductor W2 are located in the first winding layer S1. This is because, in order to stabilize the conductors in the double-layer structure, it is necessary to wind the upper conductor along the valley line of the lower conductor. Therefore, the number of turns of the upper conductor is one less than the number of turns of the lower conductor, and thus, the 6th, 8th, and 24th turns of the second conductor W2 conform to this.

[0077] In this embodiment, when counting the number of turns of the first and second wires W1 and W2 starting from the first and second terminal electrodes 41 and 42, the 1st to 6th turns constitute the first winding block B1, the 7th to 18th turns constitute the third winding block B3, and the 19th to 24th turns constitute the second winding block B2. However, in the crossing 7th and 19th turns, a portion of the wire is located in the crossing region CA1 or CA2.

[0078] Furthermore, the 7th and 19th turns of the first and second conductors W1 and W2 intersect each other in the first and second intersection areas CA1 and CA2. When the first and second conductors W1 and W2 intersect, the positional relationship between the first conductor W1 and the second conductor W2 is reversed before and after it. Specifically, when focusing on the same turn of the first conductor W1 and the second conductor W2, in the first and second winding blocks B1 and B2, the first conductor W1 is located at... Figure 2 On the left side (towards the first flange 21), the second conductor W2 is located Figure 2 On the right side (second flange 22 side), in the third winding block B3, the first wire W1 is located on the right side (second flange 22 side), and the second wire W2 is located on the left side (first flange 21 side).

[0079] In this embodiment, the number of turns of each of the first and second conductors W1 and W2 is 6 turns in the first and second winding blocks B1 and B2, and 12 turns in the third winding block B3. Therefore, there are 12 pairs of the same turn of the first conductor W1 on the left (and the second conductor on the right), and there are also 12 pairs of the same turn of the first conductor W1 on the right (and the second conductor on the left). As a result, the symmetry of the signal flowing through the first conductor W1 and the signal flowing through the second conductor W2 is increased, resulting in excellent high-frequency characteristics.

[0080] like Figure 1 As shown, in this embodiment, the first and third terminal electrodes 41 and 43 connected by the first wire W1 are at the same position in the y-direction, and the second and fourth terminal electrodes 42 and 44 connected by the second wire W2 are at the same position in the y-direction. Furthermore, from... Figure 1 As indicated by arrow V, the first and third terminal electrodes 41 and 43 connected to the first wire W1 are located on the right side, while the second and fourth terminal electrodes 42 and 44 connected to the second wire W2 are located on the left side. Therefore, when winding the first and second wires W1 and W2 clockwise from the perspective of arrow V, starting from the first and second terminal electrodes 41 and 42, as long as the wires do not cross, in the same turn of the first wire W1 and the second wire W2, the first wire W1 will be located in the right side. Figure 2 On the left side (towards the first flange 21), the second conductor W2 is located Figure 2 On the right side (second flange 22 side). In the first winding block B1, the first conductor W1 and the second conductor W2 do not cross, therefore, this positional relationship is maintained throughout the entire area of ​​the first winding block B1.

[0081] Next, when the first conductor W1 crosses the second conductor W2 in the first crossing region CA1, the positional relationship between the first conductor W1 and the second conductor W2 is reversed. Therefore, in the third winding block B3, in the same turn of the first conductor W1 and the second conductor W2, the first conductor W1 is located in... Figure 2 On the right side (on the side of the second flange 22), the second conductor W2 is located Figure 2 On the left side (towards the first flange 21). In the third winding block B3, the first conductor W1 and the second conductor W2 do not cross, therefore, this positional relationship is maintained throughout the entire area of ​​the third winding block B3.

[0082] Furthermore, when the first conductor W1 and the second conductor W2 cross in the second crossing region CA2, their positional relationship is reversed again. Therefore, in the second winding block B2, within the same turn of the first conductor W1 and the second conductor W2, the first conductor W1 is located in... Figure 2 On the left side (towards the first flange 21), the second conductor W2 is located Figure 2On the right side (second flange 22 side). In the second winding block B2, the first conductor W1 and the second conductor W2 do not cross, therefore, this positional relationship is maintained throughout the entire area of ​​the third winding block B3.

[0083] Moreover, as mentioned above, from Figure 1 When viewed with arrow V as shown, the third terminal electrode 43 is located on the right and the fourth terminal electrode 44 is located on the left. Therefore, as illustrated in the diagram... Figure 3 As shown, the first wire W1 and the second wire W2 can be connected to the third and fourth terminal electrodes 43 and 44 respectively without crossing the first wire W1 and the second wire W2 again.

[0084] In this embodiment, the common-mode filter 10 has three winding blocks, thus reducing the number of wire crossings to two. Therefore, the positional relationship between the first and second wires W1 and W2 is the same in the first winding block B1 and the second winding block B2. Consequently, the conditions at one end and the other end of the first and second wires W1 and W2 are consistent. This prevents imbalances caused by inconsistent end conditions, thereby improving high-frequency characteristics such as reflection characteristics (return loss) and noise conversion characteristics.

[0085] Conversely, assuming that the number of winding blocks is set to an even number (e.g., 2) and the number of wire crossings is set to an odd number (e.g., once), the positional relationship of the wires in the winding area closest to the first flange 21 is opposite to that of the wires in the winding area closest to the second flange 22. Therefore, in order to connect the terminals of the first wire W1 and the second wire W2 to the third and fourth terminal electrodes 43 and 44 respectively, it is necessary to make the first wire W1 and the second wire W2 cross again to restore their positional relationship to the original positional relationship.

[0086] Figure 4 This is a schematic diagram illustrating the situation where the first conductor W1 and the second conductor W2 of the common-mode filter in the comparative example cross at the final turn.

[0087] like Figure 4As shown, when viewed from arrow V, the first terminal electrode 41 is located on the right and the second terminal electrode 42 is located on the left. Therefore, when the first and second wires W1 and W2 are wound clockwise without crossing, the first wire W1 is located on the side of the first flange 21, and the second wire W2 is located on the side of the second flange 22. This positional relationship is reversed whenever the wires cross, but when the number of wire crossings is odd, it becomes reversed in the winding block closest to the second flange 22, with the first wire W1 on the side of the second flange 22 and the second wire W2 on the side of the first flange 21. In this state, when the terminals of the first and second wires W1 and W2 are connected to the third and fourth terminal electrodes 43 and 44 respectively, when viewed from arrow V, the third terminal electrode 43 is located on the right and the fourth terminal electrode 44 is located on the left. Therefore, as shown by symbol C, the first wire W1 and the second wire W2 cross at the final turn.

[0088] Here, as Figure 5 As shown, when the third terminal electrode 43 and the fourth terminal electrode 44 are separated in the y-direction, when viewed in a planar view (from the z-direction), the first wire W1 and the second wire W2 appear not to intersect at the final turn. However, in this case, as... Figure 6 As shown, the first conductor W1 and the second conductor W2 cross on the xz side of the core portion 23. That is, the first and second conductors W1 and W2 cross at the final turn, so it is necessary to restore the positional relationship of the first conductor W1 and the second conductor W2 to its original state.

[0089] Thus, when the number of wire crossings between the winding blocks is odd, a difference arises where the first and second wires W1 and W2 do not cross at the first turn on one end, but at the final turn on the other end. Therefore, a difference occurs in the way the capacitance components of the first and second wires W1 and W2 are added at one end versus the other, and this imbalance can degrade high-frequency characteristics such as reflection properties. However, in this embodiment, the common-mode filter 10 sets the number of winding blocks to three (odd number) and the number of wire crossings between the winding blocks to two (even number), thus avoiding the aforementioned imbalance. As a result, high-frequency characteristics such as reflection properties can be improved.

[0090] As explained above, the common-mode filter 10 of this embodiment sets the number of winding blocks to three (an odd number) and the number of wire crossings between the winding blocks to two (an even number). Therefore, the conditions at one end and the other end of the first and second wires W1 and W2 are consistent. As a result, the imbalance caused by inconsistent conditions at both ends is not generated, and thus, the high-frequency characteristics such as reflection characteristics (return loss) and noise transformation characteristics can be improved.

[0091] Furthermore, in this embodiment, the number of turns of the first winding block B1 is equal to the number of turns of the second winding block B2. Therefore, the symmetry of the first and second winding blocks B1 and B2 located at both ends is increased. This eliminates the product's directionality. Additionally, in this embodiment, the total number of turns of the first and second winding blocks B1 and B2 is equal to the number of turns of the third winding block B3. Therefore, the number of pairs where the first conductor W1 is located on the left side (first flange 21 side) and the second conductor W2 is located on the right side (second flange 22 side) is the same as the number of pairs where the first conductor W1 is located on the right side (second flange 22 side) and the second conductor W2 is located on the left side (first flange 21 side). This increases the symmetry between the signal flowing through the first conductor W1 and the signal flowing through the second conductor W2, thus achieving excellent high-frequency characteristics.

[0092] Furthermore, in this embodiment, the second wire W2 is wound around the first wire W1, thus increasing the winding density of the wire. This also allows for miniaturization of the axial (x-direction) dimension of the core portion 23.

[0093] The following describes several modifications of the common-mode filter 10. The structures of the modifications described below are also included within the scope of this invention.

[0094] Figure 7 This is a schematic diagram illustrating the winding layout of the common-mode filter 10A in the first modified example.

[0095] Figure 7 The common-mode filter 10A shown differs from the common-mode filter 10 of the above embodiment in that the second conductor W2 is located in the first winding layer S1 (lower layer) and the first conductor W1 is located in the second winding layer S2 (upper layer) in the third winding block B3. As shown in the first variation, the vertical relationship between the first and second conductors W1 and W2 can also be reversed in the first and second winding blocks B1 and B2 and the third winding block B3. This provides the advantage that the lengths of the first conductor W1 and the second conductor W2 are approximately equal.

[0096] Figure 8 This is a schematic diagram illustrating the winding layout of the common-mode filter 10B in the second modified example.

[0097] Figure 8 In the common-mode filter 10B shown, the third winding region A3 of the core portion 23 is subdivided into the fourth to sixth winding regions A4 to A6, and the third and fourth cross regions CA3 and CA4. The fourth to sixth winding regions A4 to A6 are arranged sequentially when viewed from the first winding region A1, forming the fourth to sixth winding blocks B4 to B6 respectively.

[0098] Furthermore, the first, second, and fifth winding blocks B1, B2, and B5 each have 4 turns, while the fourth and sixth winding blocks B4 and B6 each have 6 turns. The first and second conductors W1 and W2 intersect in the first to fourth intersection regions CA1 to CA4. Therefore, regarding the same turn of the first conductor W1 and the second conductor W2, in the odd-numbered first, second, and fifth winding blocks B1, B2, and B5, the first conductor W1 is located... Figure 8 On the left side (towards the first flange 21), the second conductor W2 is located Figure 8 On the right side (second flange 22 side), opposite to it, in the even-numbered fourth and sixth winding blocks B4 and B6, the first conductor W1 is located on the right side (second flange 22 side), and the second conductor W2 is located on the left side (first flange 21 side).

[0099] Furthermore, the number of turns of the first and second conductors W1 and W2 is 4 in the first, second and fifth winding blocks B1, B2 and B5 located in the odd-numbered blocks, and 6 in the fourth and sixth winding blocks B4 and B6 located in the even-numbered blocks. Therefore, the same turn of the first conductor W1 on the left (the second conductor on the right) becomes 12 pairs, and the same turn of the first conductor W1 on the right (the second conductor on the left) also becomes 12 pairs.

[0100] As shown in the second variation, the number of winding blocks in this invention is not necessarily three, but can also be five. That is, if an odd number of winding blocks are formed, and the first wire W1 and the second wire W2 do not cross between adjacent winding blocks in the axial direction, the number of crossings becomes an even number. Therefore, it is possible to make the conditions of one end and the other end of the first and second wires W1 and W2 consistent.

[0101] Figure 9 This is a schematic diagram illustrating the winding layout of the common-mode filter 10C in the third modified example.

[0102] Figure 9 The common-mode filter 10C shown differs from the common-mode filter 10B of the second variant in that the second conductor W2 is located in the first winding layer S1 (lower layer) and the first conductor W1 is located in the second winding layer S2 (upper layer) in the fourth and sixth winding blocks B4 and B6. Therefore, similar to the first variant, it has the advantage that the lengths of the first conductor W1 and the second conductor W2 are approximately equal.

[0103] The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. Various modifications can be made without departing from the spirit of the present invention, and these modifications are also included within the scope of the present invention.

[0104] For example, the above embodiment is described under the premise that the first and second conductors W1 and W2 are wound from the first turn to the 24th turn when manufacturing them, but it is also possible to manufacture them by winding from the 24th turn to the first turn, in the opposite way.

[0105] In addition, in the above embodiments, all winding blocks have a double-layer structure, but the first and second conductors W1 and W2 can also be double-wound in some or all of the winding blocks.

Claims

1. A common-mode filter, characterized in that, have: First flange portion; Second flange portion; The core portion is disposed between the first flange portion and the second flange portion; First and second conductors wound in the same direction around the core portion; The first terminal electrode is disposed on the first flange portion and connected to the first wire; The second terminal electrode is disposed on the first flange portion and connected to the second wire; A third terminal electrode disposed on the second flange portion and connected to the first wire; and The fourth terminal electrode is disposed on the second flange portion and connected to the second wire. The first and second conductors constitute a first winding block with multiple turns wound at one end in the axial direction of the core portion, a second winding block with multiple turns wound at the other end in the axial direction of the core portion, and a third winding block located between the first winding block and the second winding block and composed of an odd number of winding blocks with multiple turns wound. The first, second, and third winding blocks have a first winding layer located at the bottom and a second winding layer located above the first winding layer. Counting from the first winding block, the second winding block is the odd-numbered winding block. The first wire and the second wire intersect each other in the region between the first winding block and the third winding block, and also intersect each other in the region between the second winding block and the third winding block. Viewed from the first flange portion toward the second flange portion, the first terminal electrode and the third terminal electrode are located on the right side, and the second terminal electrode and the fourth terminal electrode are located on the left side. When focusing on the same turn of the first and second conductors, in the first and second winding blocks, the first conductor is located on the first flange side and the second conductor is located on the second flange side. In at least one of the odd-numbered winding blocks constituting the third winding block, the first conductor is located on the second flange side and the second conductor is located on the first flange side. The number of turns of the first winding block is equal to the number of turns of the second winding block.

2. The common-mode filter as described in claim 1, characterized in that, The third winding block has more turns than the first winding block and the second winding block.

3. The common-mode filter as described in claim 1, characterized in that, The total number of turns of the first and second winding blocks is equal to the number of turns of the third winding block.

4. The common-mode filter as described in claim 1, characterized in that, In any of the first, second, and third winding blocks, the first conductor is located in the first winding layer, and the second conductor is located in the second winding layer.

5. The common-mode filter as described in claim 1, characterized in that, In the first and second winding blocks, the first conductor is located in the first winding layer, and the second conductor is located in the second winding layer. In the third winding block, the first conductor is located in the second winding layer, and the second conductor is located in the first winding layer.

6. The common-mode filter as described in claim 1, characterized in that, The third winding block comprises a fourth, fifth, and sixth winding block arranged sequentially when viewed from the first winding block. The first wire and the second wire intersect each other in the region between the first winding block and the fourth winding block, in the region between the fourth winding block and the fifth winding block, in the region between the fifth winding block and the sixth winding block, and in the region between the sixth winding block and the second winding block.

7. The common-mode filter as described in claim 6, characterized in that, The number of turns of the first winding block is equal to the number of turns of the fifth winding block.

8. The common-mode filter as described in claim 6, characterized in that, The number of turns of the fourth winding block is equal to the number of turns of the sixth winding block.

9. The common-mode filter as described in claim 6, characterized in that, The total number of turns of the first, second, and fifth winding blocks is equal to the number of turns of the fourth and sixth winding blocks.

10. The common-mode filter as described in any one of claims 1 to 9, characterized in that, Starting from the first winding block, the number of turns of each odd-numbered winding block is less than the number of turns of each even-numbered winding block.

11. A common-mode filter, characterized in that, have: First flange portion; Second flange portion; The core portion is disposed between the first flange portion and the second flange portion, and includes a first, second, third, fourth and fifth portions arranged sequentially along the axial direction; First and second conductors, which are wound around the core portion; The first terminal electrode is disposed on the first flange portion and connected to the first wire; The second terminal electrode is disposed on the first flange portion and connected to the second wire; A third terminal electrode disposed on the second flange portion and connected to the first wire; and The fourth terminal electrode is disposed on the second flange portion and connected to the second wire. The first and second conductors are wound multiple turns in each of the first, third, and fifth portions, and each of the first, third, and fifth portions is formed having a first winding layer located at the bottom and a second winding layer located above the first winding layer. The first and second wires cross each other in each of the second and fourth sections. Viewed from the first flange portion toward the second flange portion, the first terminal electrode and the third terminal electrode are located on the right side, and the second terminal electrode and the fourth terminal electrode are located on the left side. When focusing on the same turn of the first and second conductors, in the first and fifth portions, the first conductor is located on the first flange side and the second conductor is located on the second flange side; in the third portion, the first conductor is located on the second flange side and the second conductor is located on the first flange side. The number of turns in the first part is equal to the number of turns in the fifth part.

12. The common-mode filter as described in claim 11, characterized in that, The number of turns in the third part is greater than the number of turns in the first and fifth parts, respectively.

13. The common-mode filter as described in claim 11, characterized in that, Also includes: A first flange portion is disposed at one end of the core portion in an axial direction; and The second flange is located at the other end of the core portion along its axial direction. The first and second conductors do not cross each other between the first flange portion and the first portion of the winding core portion. The first and second conductors do not cross each other between the second flange and the fifth portion of the core portion.

14. A common-mode filter, characterized in that, have: First flange portion; Second flange portion; The core portion is disposed between the first flange portion and the second flange portion; First and second conductors wound in the same direction around the core portion; The first terminal electrode is disposed on the first flange portion and connected to the first wire; The second terminal electrode is disposed on the first flange portion and connected to the second wire; A third terminal electrode disposed on the second flange portion and connected to the first wire; and The fourth terminal electrode is disposed on the second flange portion and connected to the second wire. The first and second conductors constitute the first, second, third, fourth, and fifth winding blocks arranged sequentially in the axial direction of the core portion. The first, second, third, fourth, and fifth winding blocks each have a first winding layer located at the bottom and a second winding layer located above the first winding layer. The first wire and the second wire intersect each other in the region between the first winding block and the second winding block, in the region between the second winding block and the third winding block, in the region between the third winding block and the fourth winding block, and in the region between the fourth winding block and the fifth winding block. Viewed from the first flange portion toward the second flange portion, the first terminal electrode and the third terminal electrode are located on the right side, and the second terminal electrode and the fourth terminal electrode are located on the left side. When focusing on the same turn of the first conductor and the second conductor, in the first winding block, the third winding block and the fifth winding block, the first conductor is located on the first flange side and the second conductor is located on the second flange side; in the second winding block and the fourth winding block, the first conductor is located on the second flange side and the second conductor is located on the first flange side.

15. The common-mode filter as described in claim 14, characterized in that, The number of turns of the first winding block is equal to the number of turns of the fifth winding block.

16. The common-mode filter as described in claim 15, characterized in that, The number of turns of the second winding block is equal to the number of turns of the fourth winding block.

17. The common-mode filter as described in claim 16, characterized in that, The number of turns of the first winding block is different from the number of turns of the second winding block.

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