JP2003173918A - Wire-wound coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wire-wound coil that can suppress the influence of a magnetic core upon the stray capacitance of the coil. <P>SOLUTION: In this wire-wound coil, windings 37 and 47 are respectively wound in single layers around the cylindrical drum sections 33 and 43 of bobbins 32 and 42 and the bobbins 32 and 42 are mounted and fixed on a printed board 65 through lead terminals 54b and 55b, etc. In addition, a magnetic core 50 is mounted and fixed on the printed board 65 by means of a fastener 60. Moreover, spatial gaps G1 are respectively formed between the internal wall surfaces of the holes 33a and 43a of the cylindrical drum sections 33 and 43 of the bobbins 32 and 42 and the outer peripheral surfaces 52aa and 52ba of the leg sections of the magnetic core 50. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire wound coil, and more particularly to a wire wound coil used for an inductor, a common mode choke coil, a normal mode choke coil, a transformer and the like.

[0002]

2. Description of the Related Art Generally, the insertion loss-frequency characteristic of a common mode choke coil exhibits inductive characteristics due to the common mode inductance L in the frequency region lower than the self-resonance frequency, and the common mode choke coil in the frequency region higher than the self-resonance frequency. 3 shows the capacitive characteristic due to the stray capacitance C that occurs in the. The self-resonant frequency and the inductive characteristic and the capacitive characteristic when measured in the 50Ω system are represented by the following equations. Self-resonant frequency: fr = 1 / [2π (LC) ^1/2 ] Inductive characteristic curve: Insertion loss = 10 log [1+ (ωL
/ 100) ² ] Capacitive characteristic curve: insertion loss = 10 log [1 + 1 /
(100ωC) ² ]

In order to improve the noise removal performance of the common mode choke coil in the high frequency band, it is necessary to reduce the stray capacitance C. The main factors of the generation of stray capacitance are roughly the influence of the winding structure of the winding, the influence of the bobbin, and the influence of the magnetic core. Here, in order to reduce the influence of the bobbin, it is necessary to change the material of the bobbin with a low dielectric constant or to reduce the thickness of the bobbin. However, when using the common mode choke coil for AC power supply lines, it is necessary to secure the flame retardancy, relative temperature index and insulation distance of the safety standard. Further, in the existing common mode choke coil, a material having a dielectric constant ε of about 2 to 4 and 0.5 to 1.0 is used.
Since a bobbin with a wall thickness of about mm is generally used, the stray capacitance C can be changed by changing the bobbin material and the bobbin wall thickness.
It is difficult to reduce the influence of the bobbin.

Therefore, in order to reduce the stray capacitance C generated in the common mode choke coil, it is important to reduce the influence of the winding structure of the winding and the influence of the magnetic core. The ratio of these influences depends on the winding structure of the winding. For example, as a winding structure of a winding that is considered to generate less stray capacitance, there is a so-called split winding in which the winding is divided and wound as compared with the related art.

FIG. 19 shows a structure of a conventional common mode choke coil 1 in which windings 7 and 17 are separately wound. The common mode choke coil 1 includes a magnetic core composed of two U-shaped core members 20 and 21 and two bobbins 2 and 12. Bobbins 2 and 12 are
It has tubular body portions 3 and 13 and collar portions 4,5, 6, 14, 15, 16 provided on the tubular body portions 3 and 13.

The winding 7 includes a first winding portion 7a and a second winding portion 7
b is electrically connected in series. First winding portion 7a
Is wound between the collar portions 4 and 6 of the bobbin 2, and the second winding portion 7
b is wound between the collar portions 5 and 6. Similarly, winding 1
7 is configured by electrically connecting the first winding portion 17a and the second winding portion 17b in series. The first winding portion 17a is the bobbin 12
The second winding portion 17b is wound between the collar portions 14 and 16, and the second winding portion 17b is wound between the collar portions 15 and 16.

The bobbins 2 and 12 have their cylindrical body portions 3 and 13 respectively.
Are arranged so that they are parallel to each other. Then, the leg portions 20b and 21b of the core members 20 and 21 are inserted into the holes 3a and 13a of the tubular body portions 3 and 13, respectively. The core members 20 and 21 have a pair of leg portions 20b and 21b whose tip surfaces abut against each other in the holes 3a and 13a to form one closed magnetic path.

In the common mode choke coil 1 having the above structure, the stray capacitance is almost proportional to the winding width, so that the windings 7 and 17 are respectively divided into two winding portions 7a and 7a.
When divided into b, 17a, and 17b, the stray capacitance of one winding portion is ½ of the stray capacitance of the undivided winding. Further, since the winding portions 7a and 7b or 17a and 17b are connected in series, the stray capacitance of each of the windings 7 and 17 of the two-division winding common mode choke coil 1 is the floating of the winding before the division. It becomes 1/4 of the capacity (for example, about 4.0 pF).

As another winding structure of the winding, there is a so-called single layer winding in which the winding is wound in only one layer. In this winding structure, the adjacent winding portions are only in the left-right direction, and the stray capacitance generated in the adjacent winding portions is connected in series for the number of windings. Can be made smaller. For example, the stray capacitance, which was 4.0 pF in the case of split winding, is 0.5 p
Can be F. However, the obtained inductance value becomes small.

Further, as another winding structure of the winding, there is a so-called single-layer parallel winding in which a plurality of single-layer windings are stacked in parallel. In this winding structure, in order to solve the problem that the inductance value of the single-layer winding is small, the diameter of the winding is made small and the number of turns of the winding per one stage is increased to obtain a large inductance value. And, in order to keep the DC resistance value of the winding, which becomes larger, low,
The windings stacked in multiple stages are connected in parallel. That is, the single-layer parallel winding can obtain a relatively large inductance while having the characteristics of the single-layer winding. However, the stray capacitance of the wound structure is larger than that of the single layer winding.

Table 1 shows the general magnitude relations of the stray capacitance, the DC resistance value and the inductance value of the winding due to the difference in the winding structure when wound with the same winding diameter. .

[0012]

[Table 1]

[0013]

Generally, the winding area of the windings 7 and 17 of the common mode choke coil 1 is the window area of the core members 20 and 21 forming the closed magnetic path, the bobbin 2, and the bobbin 2. It is limited by the wall thickness of 12 and the insulation distance. Conventional common mode choke coil 1
Is designed so that there is no wasted space in order to obtain the maximum inductance value within the limited winding possible area. Therefore, the core members 20, 21 and the bobbins 2, 12
Between them, or between the core members 20 and 21 and the windings 7 and 17, only the minimum space gap required for assembly work or safety standards was provided. Therefore, the stray capacitance due to the core members 20 and 21 is relatively large, and the stray capacitance is less generated as compared with the multi-layer common mode choke coil without the central collar portions 6 and 16 that divide the windings 7 and 17 into two. In the case of the common mode choke coil 1 which adopts the winding structure of the windings 7 and 17, which is defined as above, the influence is a value that cannot be ignored. In particular, in single-layer winding or single-layer parallel winding in which the generation of stray capacitance is small, the influence of the core members 20 and 21 on the stray capacitance is extremely large.

Therefore, an object of the present invention is to provide a wire-wound coil having a structure capable of suppressing the influence of the magnetic core on the stray capacitance.

[0015]

In order to achieve the above-mentioned object, a wire wound coil according to the present invention has (a) at least one bobbin having a tubular body, and (b) each bobbin cylinder. (C) Each leg of the tubular body of the bobbin has a leg portion that is inserted into the cylindrical body portion to close the magnetic field. A magnetic core forming a path and (d) a metal fitting for holding the magnetic core are provided. (E) The bobbin is mounted and fixed on the wiring board, and the magnetic core is wired through the metal fitting. By being mounted and fixed on the substrate, a first space gap is provided between the inner peripheral surface of the hole of each tubular body portion of the bobbin and the outer peripheral surface of the leg portion of the magnetic core, and A second space gap is provided between each collar and the arm of the magnetic core that runs in parallel with the collar. It is only or.

The wire wound coil according to the present invention is
(F) at least one bobbin having a tubular body portion and a collar portion provided on the tubular body portion, (g) single-layer winding wire provided on each tubular body portion of the bobbin, and (H) any one of the single-layer parallel-winding windings, (h) a magnetic core in which a leg portion is inserted into a hole of each tubular body portion of the bobbin to form a closed magnetic circuit, and (i) a magnetic body. While holding the core, each bobbin is provided with a stopper for positioning and fixing the magnetic core, and (j) the inner peripheral surface of the hole of each tubular body of the bobbin fixed to the stopper, A first space gap is provided between the leg of the magnetic core fixed to the stopper and the outer peripheral surface of the leg, and each collar of the bobbin and the arm of the magnetic core running in parallel with the collar. A second space gap is provided between the parts.

Further, the wire wound coil according to the present invention is
(K) at least one bobbin having a tubular body portion and a collar portion provided on the tubular body portion, and (l) a single-layer winding provided on each tubular body portion of the bobbin, and (M) a single core parallel winding, (m) a magnetic core having a leg inserted through a hole in each cylindrical body of the bobbin to form a closed magnetic circuit, and (n) cylindrical A first spacer member disposed between the inner peripheral surface of the hole of the body and the outer peripheral surface of the leg of the magnetic core;
(O) A second spacer member disposed between each collar portion of the bobbin and an arm portion of the magnetic core that runs parallel to the collar portion, and (p) a first spacer member. Thus, a first space gap is formed between the inner peripheral surface of the hole of each cylindrical body of the bobbin and the outer peripheral surface of the leg of the magnetic core inserted through the hole of the cylindrical body. The second spacer member is provided with a second space gap between each collar portion of the bobbin and the arm portion of the magnetic core that runs parallel to the collar portion.

With the above construction, a space gap having a predetermined size is secured between the magnetic core and the winding, and the distance between the magnetic core and the winding is expanded. Therefore, the influence of the magnetic core on the stray capacitance is reduced.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the wire wound coil according to the present invention will be described below with reference to the accompanying drawings. In the present embodiment, a common mode choke coil will be described as an example.

[First Embodiment, FIGS. 1 to 8] The appearance of a common mode choke coil is shown in FIG. 1, its front view is shown in FIG. 2, and its horizontal sectional view and partial vertical sectional view are shown in FIG. 3 and FIG. It shows in FIG. 4 and an electrical equivalent circuit diagram is shown in FIG.
The common mode choke coil 31 is a magnetic core 50 including two U-shaped core members 50a and 50b.
And two bobbins 32 and 42 and a stopper 60.

Each of the bobbins 32 and 42 has a cylindrical body portion 3.
3 and 43, and collar portions 34, 35, 44 and 45 provided at both ends of the tubular body portions 33 and 43. Collar part 34,
35, 44 and 45 respectively have lead terminals 54a and 54
b, 55a, 55b are planted. Bobbins 32,4
2 are arranged so that their cylindrical body portions 33 and 43 are parallel to each other. The bobbins 32, 42 are made of resin or resin containing magnetic powder. Bobbins 32, 42
2, the lead terminals 54a to 55b are inserted into the through holes 66 and 67 provided in the wiring board 65 and then soldered to be mounted and fixed to the wiring board 65. In FIG. 2, reference numeral 69 is solder. In addition, in the present embodiment, the lead terminals 54a to 55b.
The bobbins 32 and 42 are mounted and fixed to the wiring board 65 by utilizing the above. However, the present invention is not limited to this, and the bobbins 32 and 42 can be mounted to the wiring board 65 via a stand with lead terminals.
It may be mounted and fixed on. The wiring board 65 includes not only a printed board having a wiring pattern formed on the front surface or the front and back surfaces but also a multilayer board having a built-in wiring pattern.

Each of the windings 37, 47 has a bobbin 32, 4
A single layer is wound around the outer peripheries of the two tubular body portions 33, 43.
The windings 37 and 47 have the same number of turns. Both ends of the winding 37 are electrically connected to lead terminals 54a and 54b provided on the bobbin 32, respectively. Similarly, both ends of the winding wire 47 are electrically connected to lead terminals 55 a and 55 b provided on the bobbin 42, respectively.

Core member 5 constituting the magnetic core 50
0a and 50b are arm portions 51a and 51b, and a leg portion 52 extending from both ends of the arm portions 51a and 51b at right angles.
a and 52b. And bobbins 32, 42
In the holes 33a and 43a (the cross-sectional shape is rectangular) of the cylindrical body portions 33 and 43 of No. 1, the leg portions 52a of the core members 50a and 50b,
52b (the cross-sectional shape is rectangular) are respectively inserted. These core members 50a, 50b have their respective end portions 52a, 52b having their distal end surfaces abutted with each other in the holes 33a, 43a to form one annular (square-shaped) closed magnetic path. The magnetic core 50 includes two core members 50a,
Although it is composed of 50b, one annular (square-shaped) core member may be used. In this case, the bobbin is composed of two bobbin members, and the bobbin member is closed after the core member is inserted.

Further, between the bobbins 32 and 42, there is arranged a U-shaped stopper 60 for firmly adhering the abutting surfaces of the core members 50a and 50b. As shown in FIG. 2, the stopper 60 is soldered to the electrode land 68 provided on the surface of the wiring board 65, and mounted and fixed.
The magnetic core 50 is attached to the wiring board 65 by the fastener 60.
Is held and positioned above. A minimum necessary amount of adhesive (not shown) is applied and fixed between the magnetic core 50 and the fastener 60. Although the fastener 60 of the first embodiment is mounted and fixed on the surface of the wiring board 65 as shown in FIG. 2, the bottom of the fastener 60 is floated from the wiring board 65, and a lead pin or the like is attached to the bottom. May be provided and inserted into the through hole of the wiring board 65 to be mounted and fixed.

Here, as shown in FIGS. 2 to 4, the outer peripheral surface 52a of the leg portions 52a and 52b of the core members 50a and 50b.
A space gap G1 having a predetermined size is formed between a and 52ba and the inner wall surfaces of the holes 33a and 43a. In addition,
The size of the horizontal space gap G1 and the size of the vertical space gap G1 are preferably the same as in the present embodiment, but needless to say, they may be different. Further, as shown in FIG. 3, the core members 50a, 50b
The arm portions 51a, 51b of the bobbin run parallel to the collar portions 34, 35, 44, 45 of the bobbins 32, 42, respectively. Then, the inner side surfaces 51aa, 51bb of the arm portions 51a, 51b and the outer main surfaces 34a, 35a, 4 of the collar portions 34, 35, 44, 45.
A space gap G2 having a predetermined size is formed between the gaps 4a and 45a. That is, the magnetic core 50 and the bobbin 3
2, 42 are positioned in a non-contact state with each other via the fastener 60 and the wiring board 65.

The common mode choke coil 31 has a stray capacitance C if the size of the space gaps G1 and G2 is increased.
Becomes smaller. However, as the space gaps G1 and G2 are increased, the component size also increases. Therefore, it is necessary to determine the size range of the space gaps G1 and G2 that can efficiently reduce the stray capacitance. The size ranges of the space gaps G1 and G2 that can efficiently reduce the stray capacitance C are G1 = 0.3 to 1.5 mm and G2 = 0.7.
~ 4.0 mm. More preferably, G1 = 0.5-
1.0 mm and G2 = 1.0 to 2.0 mm. The lower limit of the size range of the space gaps G1 and G2 was determined for the reason of the electrical characteristics of the common mode choke coil 31. On the other hand, the upper limit of the dimensional range of the space gaps G1 and G2 can achieve downsizing of the component size and a large inductance value (when the component size is fixed, basically,
The smaller the space gap, the more winding space there is, so
The inductance value can be increased).

The material of the core members 50a and 50b is Mn.
-Zn type ferrite and Ni-Zn type ferrite are used. In particular, since Mn-Zn-based ferrite has a high magnetic permeability, a large inductance value of several tens to several hundreds mH can be obtained even if the number of windings of the windings 37 and 47 is relatively small. Incidentally, in order to suppress the noise voltage from the low frequency band (several KHz), an inductance value of several tens to several hundreds mH is required.

In the common mode choke coil 31 having the above-described structure, the windings 37 and 47 have a common mode (in phase).
When the noise current flows, magnetic flux is generated in the magnetic core 50 in the same direction by the windings 37 and 47. This magnetic flux is consumed while circulating in the magnetic core 50.

The common mode choke coil 31 has inner surfaces 5 of the arm portions 51a and 51b of the core members 50a and 50b.
1aa, 51bb and the collar portions 34, 3 of the bobbins 32, 42.
5, 44, 45 outer major surfaces 34a, 35a, 44a, 4
The space gap G2 is formed without providing a spacer or the like between the gap 5G and the space 5a. Further, the core member 50a,
Outer peripheral surface of the leg portions 52a and 52b of 50b (including four surfaces of an upper surface, a lower surface, an inner surface and an outer surface) 52
aa, 52ba and holes 33a, 43 of bobbins 32, 42
A space gap G1 is formed without providing a spacer or the like between the inner wall surface of a and the inner wall surface. Since the dielectric constant of air is low, the influence of the magnetic core 50 on the stray capacitance C can be minimized. For example, in the case of a conventional single layer winding common mode choke coil, 0.5 pF
In the case of the single-layer winding common mode choke coil 31 of the present embodiment, the stray capacitance C that was described above could be less than 0.3 pF. That is, a stray capacitance reducing effect of 40% or more was obtained. As a result, it is possible to obtain a common mode choke coil having excellent noise removal performance in a high frequency region.

By the way, when the present invention is applied to the conventional split winding common mode choke coil, the stray capacitance C, which was 2.0 pF, is reduced to only 1.8 pF and is 10%.
Only the effect of reducing the stray capacitance was obtained.

By the way, the single layer winding has a winding structure capable of suppressing the stray capacitance C most, but since it is difficult to obtain a large inductance value, it is possible to sufficiently suppress the common mode noise in the low frequency band. difficult. Therefore,
As shown in FIG. 6, the tubular body portions 33 of the bobbins 32, 42,
43, windings 37a, 37b, 37c and winding 47
It is also possible to have a single-layer parallel winding structure in which a, 47b, and 47c are sequentially wound in a single layer and stacked in a plurality of stages. Figure 7
It is a graph which shows the insertion loss-frequency characteristic of the single mode parallel winding common mode choke coil 31A (see the solid line 61). For comparison, FIG. 7 also shows the insertion loss-frequency characteristics (see the dotted line 62) of the conventional single layer parallel winding common mode choke coil.

The common mode choke coil 31B shown in FIG. 8 has a stopper 70. The stopper 70 allows the abutting surfaces of the core members 50a and 50b to be in close contact with each other, and the bobbins 32 and 42 and the magnetic core 5 to each other.
Position and fix 0. That is, the magnetic core 50 and the bobbins 32, 42 are positioned via the stopper 70. The stopper 70 positions the bobbins 32 and 42 on four arm portions 71 (the arm portion on the left back side in FIG. 8 is not shown). The stopper 70 is a bobbin 3
The shape is arbitrary as long as it is a structure for positioning the front and rear, the upper and lower sides, and the left and right sides of the No. By the stopper 70, the inner side surfaces 5 of the arm portions 51a, 51b of the core members 50a, 50b
1aa, 51bb and the collar portions 34, 3 of the bobbins 32, 42.
5, 44, 45 outer major surfaces 34a, 35a, 44a, 4
The space gap G2 is formed without providing a spacer or the like between the gap 5G and the space 5a. Further, the core member 50a,
Outer peripheral surface of the leg portions 52a and 52b of 50b (including four surfaces of an upper surface, a lower surface, an inner surface and an outer surface) 52
aa, 52ba and holes 33a, 43 of bobbins 32, 42
A space gap G1 is formed without providing a spacer or the like between the inner wall surface of a and the inner wall surface. The common mode choke coil 31B has the same effects as the common mode choke coil 31.

[Second Embodiment, FIGS. 9 to 18] In the second embodiment, space gaps G1 and G2 are formed by using spacer members.
The common mode choke coil that secures the above will be described.

In the common mode choke coil 31C shown in FIGS. 9 and 10, the first spacer member 80 shown in FIG. 11 is attached to the leg portions 52a and 52b of the core members 50a and 50b. The spacer member 80 includes a tubular portion 81 having a rectangular cross section, and an outer peripheral surface (four surfaces) of the tubular portion 81.
Rail-shaped projections 82 are provided on each of the above. A taper is formed at the tip of each rail-shaped projection 82, and the leg portions 52a and 52b of the core members 50a and 50b are attached to the bobbin 3.
The holes 33a and 43a of 2, 42 are easily inserted. Due to the rail-shaped projections 82 of the spacer member 80, the outer peripheral surfaces 52aa and 52ba of the leg portions 52a and 52b.
And a space gap G1 having a predetermined size is formed between the inner wall surfaces of the holes 33a and 43a.

On the other hand, the arm portions 51 of the core members 50a and 50b
inner surfaces 51aa and 51bb of the a and 51b and the bobbin 3
2, 42 outer flanges 34, 35, 44, 45 outer main surface 34
a, 35a, 44a and 45a are respectively shown in FIG.
A second spacer member 85 shown in 2 (A) is provided. The spacer member 85 has an L-shaped cross section.
It is in the shape of a letter and comprises an insertion portion 85a and a stopper portion 85b. The insertion portion 85a has a tapered tip portion, and is easily inserted between the arm portions 51a and 51b and the collar portions 34, 35, 44 and 45. The stopper portion 85b includes the arm portion 51a,
Lock to 51b. Therefore, by the insertion portion 85a, the inner side surfaces 51aa, 51bb of the arm portions 51a, 51b and the outer main surfaces 34a, 35a, 4 of the collar portions 34, 35, 44, 45 are formed.
A space gap G2 having a predetermined size is formed between the gaps 4a and 45a. Magnetic core 50 and spacer members 80, 85
In between, a minimum necessary amount of adhesive (not shown) is applied and fixed. This common mode choke coil 3
1C has the same effects as the common mode choke coil 31.

Incidentally, instead of the spacer member 85, FIG.
2, the spacer member 86 shown in (B) or (C),
87 may be used. The spacer member 86 includes a stopper portion 86b and insertion portions 86a provided at both ends of the stopper portion 86b. The spacer member 86 is fixed to the magnetic core 50 by sandwiching the arm portions 51a and 51b with the two insertion portions 86a. In addition, the spacer member 87
Is a frame-shaped stopper portion 87b and the stopper portion 87b.
And an insertion portion 87a extending vertically to the four corners.
The spacer member 87 includes the four insertion portions 87 a and the arm portion 51.
By sandwiching a and 51b, they are fixed to the magnetic core 50.

The common mode choke coil 31D shown in FIG. 13 has a leg portion 52 of the core members 50a and 50b.
Two first spacer members 80 (provided that the length is short) shown in FIG. 11 are attached to each of a and 52b. Due to the short rail-shaped projection 82 of the spacer member 80, the outer peripheral surface 52a of the leg portions 52a and 52b is formed.
A space gap G1 having a predetermined size is formed between a and 52ba and the inner wall surfaces of the holes 33a and 43a.

The common mode choke coil 31E shown in FIG. 14 has holes 33a and 43 in bobbins 32 and 42.
The first spacer members 90 shown in FIG. 15 are provided in the openings at both ends of a, respectively. The spacer member 90 includes a frame-shaped frame body 91 and a protrusion 92 extending perpendicularly to the frame body 91. The protrusion 92 has a tapered shape, and the spacer member 90 has holes 33a and 43a.
It is easy to insert into. This spacer member 9
With the frame body 91 and the projection 92 of 0, the leg portions 52a, 52b
A space gap G1 having a predetermined size is formed between the outer peripheral surfaces 52aa and 52ba of the above and the inner wall surfaces of the holes 33a and 43a.

Further, as shown in FIGS. 16 and 17, the bobbins 32 and 42 are connected with their axes aligned and connected, and the leg portions 52a and 52b of one of the core members 50a and 50b are inserted into the communicating holes 33a and 43a. The common mode choke coil 31F having the above structure may be used. At this time, bobbin 3
Structure in which the inner side surfaces of the leg portions 52a and 52b of the core members 50a and 50b contact one of the inner wall surfaces of the holes 33a and 43a of 2, 42, that is, the outer side surface, the upper side surface and the lower side surface of the leg portions 52a and 52b. Even in the structure in which the space gap G1 having a predetermined size is formed between the inner wall surfaces of the holes 33a and 43a, the stray capacitance can be reduced.

Here, the holes 33a, 4 of the bobbins 32, 42
A groove 101 is provided on each of the three inner wall surfaces of 3a. Guided by the groove 101, three first spacer members 100 are inserted into each of the bobbins 32 and 42.
With the rail-shaped spacer member 100, the outer peripheral surfaces 52a of the leg portions 52a and 52b of the core members 50a and 50b are formed.
A space gap G1 having a predetermined size is formed between a and 52ba and the inner wall surfaces of the holes 33a and 43a. However, as shown in FIG. 18, grooves 103 are provided on the three outer wall surfaces of each of the leg portions 52a and 52b of the core members 50a and 50b, and the spacer member 100 is inserted by the guide of the grooves 103. Good.

[Other Embodiments] The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the gist thereof. For example, a square-shaped integral core or a Japanese letter-shaped integral core may be used as the magnetic core, and a bobbin having a gear structure divided into two or more may be used as the bobbin. Further, in the above-described embodiment, the two-line type having two windings has been described, but the three-line type or more having three or more windings may be used.

In addition to the common mode choke coil, the present invention has two bobbins 32 and 42 in FIG.
The inductor may have a structure in which one of the bobbins is omitted. It can also be applied to coils such as normal mode choke coils and transformers. Further, the present invention can be applied to a so-called hybrid choke coil in which common mode noise (normal mode noise) is removed by the core and normal mode noise (common mode noise) is removed by the bobbin. In addition to the above, the effect of the present invention can be exerted against normal mode noise.

The spacer member does not have to have a rectangular cross section, and may have a semicircular shape, a trapezoidal shape, a triangular shape, or the like. In particular, the contact surface between the spacer member and the core members 50a and 50b is preferably a flat surface from the holding surface of the core members 50a and 50b, and the contact area from the viewpoint of reducing the stray capacitance as much as possible. Since it is better that there is less, the contact surface should have an R-shaped surface.

[0044]

As is apparent from the above description, according to the present invention, a space gap of a predetermined size is secured between the magnetic core and the winding, and the space between the magnetic core and the winding is secured. The distance is expanded. Therefore, the influence of the magnetic core on the stray capacitance can be reduced. As a result, it is possible to obtain a wire-wound coil having excellent electrical characteristics in the high frequency region.

[Brief description of drawings]

FIG. 1 is an external perspective view showing an embodiment of a wire-wound coil according to the present invention.

FIG. 2 is a front view of the wire-wound coil shown in FIG.

FIG. 3 is a horizontal sectional view of the wire-wound coil shown in FIG.

FIG. 4 is a partial vertical sectional view of the wire-wound coil shown in FIG.

5 is an electrical equivalent circuit diagram of the wire-wound coil shown in FIG.

FIG. 6 is a horizontal sectional view showing another embodiment of the wire-wound coil according to the present invention.

7 is a graph showing insertion loss-frequency characteristics of the wire-wound coil shown in FIG.

FIG. 8 is an external perspective view showing still another embodiment of the wire wound coil according to the present invention.

FIG. 9 is a horizontal sectional view showing still another embodiment of the wire-wound coil according to the present invention.

10 is a partial vertical sectional view of the wire-wound coil shown in FIG.

FIG. 11 is a first diagram of the wire wound coil shown in FIG.
3 is a perspective view showing the spacer member of FIG.

FIG. 12 is a second view used in the wire-wound coil shown in FIG.
3 is a perspective view showing the spacer member of FIG.

FIG. 13 is a horizontal cross-sectional view showing still another embodiment of the wire wound coil according to the present invention.

FIG. 14 is a horizontal sectional view showing still another embodiment of the wire-wound coil according to the present invention.

15 is a perspective view showing a first spacer member used in the wire-wound coil shown in FIG.

FIG. 16 is a horizontal sectional view showing still another embodiment of the wire-wound coil according to the present invention.

17 is a partial vertical sectional view of the wire-wound coil shown in FIG.

FIG. 18 is a partial vertical sectional view showing a modification of the wire-wound coil shown in FIG.

FIG. 19 is a horizontal sectional view showing a conventional wire-wound coil.

[Explanation of symbols]

31, 31A to 31F ... Common mode choke coil 32, 42 ... Bobbin 33, 43 ... Cylindrical body 33a, 43a ... holes 34, 35, 44, 45 ... Collar part 37, 37a to 37c, 47, 47a to 47c ... Winding 50 ... Magnetic core 51a, 51b ... Arms 52a, 52b ... legs 60, 70 ... Stopper 65 ... Wiring board 80, 90, 100 ... First spacer member 85, 86, 87 ... Second spacer member G1, G2 ... Spatial gap

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01F 27/32 H01F 27/32 B (72) Inventor Takaaki Oi 2 26-10 Tenjin, Nagaokakyo, Kyoto Prefecture Murata Manufacturing F-term (reference) 5E044 BB05 CA09 5E059 LL16

Claims (9)

[Claims] 1. At least one bobbin having a tubular body, and one of a single-layer winding and a single-layer parallel winding provided on each tubular body of the bobbin. A leg part is inserted into the hole of each tubular body part of the bobbin to form a closed magnetic path, and a stopper for holding the magnetic core, the bobbin is a wiring board And the magnetic core is mounted and fixed to the wiring board via the stopper, so that the inner peripheral surface of the hole of each tubular body of the bobbin and the magnetic core are fixed. A wire-wound coil, wherein a first space gap is provided between the outer peripheral surface of the leg portion of the. 2. A bobbin having at least one tubular body portion and a collar portion provided on the tubular body portion; a single-layer winding wire provided on each tubular body portion of the bobbin; One of the windings of the single-layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, the magnetic core forming a closed magnetic path, and the magnetic core is held. And a bobbin mounted and fixed to the wiring board, and the magnetic core is mounted and fixed to the wiring board via the stopper, thereby forming a collar portion of each bobbin. A wire-wound coil, wherein a second space gap is provided between the collar portion and an arm portion of the magnetic core that runs in parallel. 3. A bobbin having at least one tubular body portion and a collar portion provided on the tubular body portion; a single-layer winding wire provided on each tubular body portion of the bobbin; One of the windings of the single-layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, the magnetic core forming a closed magnetic path, and the magnetic core is held. The bobbin is mounted and fixed on the wiring board, and the magnetic core is mounted and fixed on the wiring board via the holding metal, so that the cylindrical body of each bobbin is fixed. A first space gap is provided between the inner peripheral surface of the hole of the portion and the outer peripheral surface of the leg portion of the magnetic core, and each flange of the bobbin and the parallel running to the flange portion are provided. A wire-type coil having a second spatial gap provided between the magnetic core and the arm. . 4. At least one bobbin having a tubular body, and any one of a single-layer winding and a single-layer parallel winding provided on each tubular body of the bobbin. A leg portion is inserted into a hole of each tubular body portion of the bobbin to form a closed magnetic path, and the magnetic body core is held, and each of the bobbins and the magnetic body core are positioned. An inner peripheral surface of the hole of each tubular body of the bobbin fixed to the stopper, and an outer circumference of the leg portion of the magnetic core fixed to the stopper. A wire-wound coil, wherein a first spatial gap is provided between the coil and the surface. 5. At least one bobbin having a tubular body and a collar portion provided on the tubular body, a single-layer winding wire provided on each tubular body of the bobbin, and One of the windings of the single-layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, the magnetic core forming a closed magnetic path, and the magnetic core is held. In addition, each bobbin and a stopper for positioning and fixing the magnetic core are provided, and each collar of the bobbin fixed to the stopper and the magnetic body running in parallel with the collar. Second between the core arm
A wire-wound coil characterized by having a space gap. 6. A bobbin having at least one bobbin having a tubular body and a flange provided on the tubular body, and a single-layer winding wire provided on each tubular body of the bobbin. One of the windings of the single-layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, the magnetic core forming a closed magnetic path, and the magnetic core is held. Along with each of the bobbins, a stopper for positioning and fixing the magnetic core is provided, the inner peripheral surface of the hole of the tubular body of each bobbin fixed to the stopper, and the stopper. A first spatial gap is provided between the leg of the magnetic core and the outer peripheral surface of the leg of the magnetic core, and each collar of the bobbin and the arm of the magnetic core running in parallel with the collar. A wire-wound coil, wherein a second space gap is provided between the coil and the part. 7. A bobbin having at least one tubular body and a brim provided on the tubular body, a single-layer winding wire provided on each tubular body of the bobbin, and One of the windings of the single layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, a magnetic core forming a closed magnetic circuit, and the hole of the tubular body portion. A first spacer member disposed between the inner peripheral surface of the bobbin and the outer peripheral surface of the leg portion of the magnetic core. A winding space, wherein a first space gap is provided between an inner peripheral surface of the hole and an outer peripheral surface of the leg portion of the magnetic core that is inserted into the hole of the tubular body portion. coil. 8. A bobbin having at least one bobbin having a tubular body and a collar provided on the tubular body, a single-layer winding wire provided on each tubular body of the bobbin, and One of the windings of the single-layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, the magnetic core forming a closed magnetic path, and the collar portion of each bobbin And a second spacer member disposed between the arm portion of the magnetic core that runs parallel to the collar portion, and the collar portion of each of the bobbins is provided by the second spacer member. A wire-wound coil, wherein a second space gap is provided between the collar portion and an arm portion of the magnetic core that runs in parallel. 9. At least one bobbin having a tubular body and a collar portion provided on the tubular body, a single-layer winding provided on each tubular body of the bobbin, and One of the windings of the single layer parallel winding, the leg portion is inserted into the hole of each tubular body portion of the bobbin, a magnetic core forming a closed magnetic circuit, and the hole of the tubular body portion. A first spacer member disposed between the inner peripheral surface of the bobbin and the outer peripheral surface of the leg portion of the magnetic core, each collar of the bobbin, and the magnetic body running in parallel with the collar. A second spacer member arranged between the arm portion of the core and the second spacer member, wherein the first spacer member causes the inner peripheral surface of the hole of each tubular body portion of the bobbin and the tubular body A first space gap is provided between the magnetic core and the outer peripheral surface of the leg portion of the magnetic core, which is inserted into the hole of the portion, and by the second spacer member, A wire-wound coil, wherein a second space gap is provided between each collar portion of the bobbin and an arm portion of the magnetic core that runs parallel to the collar portion.