JP2004235709A - Distributed constant filter element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a distributed constant filter element capable of adjusting line capacity while ensuring satisfactory inductance and withstand voltage, and capable of adjusting interground capacity without providing external electronic components. <P>SOLUTION: The distributed constant filter element 1 is provided with a ground conductor 3 for generating interground capacity between a coil 6 formed by winding a conductor wire 7 and the wire 7. In this element, a laminate LA which is provided with the coil 6, a close conductor 5 provided between the coil 6 and the conductor 3 so as to be close to the coil 6, and a dielectric 4 having insulation and being provided between the conductors 3 and 5 is arranged on one surface side of the conductor 3. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coil formed by winding a conductive wire, and a distributed constant filter element including a ground conductor that generates a ground-to-ground capacitance between the coil and the coil.
[0002]
[Prior art]
A choke coil (particularly shown in FIG. 3) used in a noise filter disclosed in Japanese Patent Application Laid-Open No. 11-346472 is known as this type of distributed constant type filter element. The choke coil is configured to be covered with a conductor (C) that generates a floating capacitance with the choke coil, and that the conductor (C) is connected (grounded) to a ground potential. In this choke coil, the stray capacitance generated between the choke coil and the conductor (C) acts as a line bypass capacitor (capacitance between grounds) to form a distributed constant filter. The damping characteristics have been dramatically improved.
[0003]
[Patent Document 1]
JP-A-11-346472 (pages 3-4, FIG. 3)
[0004]
[Problems to be solved by the invention]
However, the conventional distributed constant filter element has the following problems to be solved. That is, in a distributed constant type filter element (choke coil) of this type, an inexpensive enameled copper wire is often used as a conductor wound around a magnetic core (in the above publication, a toroidal core). Accordingly, since the insulating coating of the enameled copper wire is thin, the distance between the conductor and the conductor (C) is shortened. As a result, there is a problem that the withstand voltage is reduced and it is difficult to secure sufficient safety. I do. On the other hand, in order to increase the withstand voltage, a method of using a conductive wire having a thick insulating coating and a method of ensuring a sufficient distance between the choke coil and the conductor (C) are considered. However, the former method has a problem that it is difficult to secure a sufficient inductance due to a decrease in the number of times of winding around the magnetic core. In addition, the latter method has a problem that it is difficult to obtain a desired attenuation characteristic due to a decrease in capacitance between grounds.
[0005]
Further, when adjusting the attenuation characteristic of the distributed constant filter element, it is necessary to adjust the line capacitance and the ground capacitance. In this case, in this distributed constant filter element, the line capacitance can be adjusted by changing the pitch between the conductors forming the choke coil. However, according to this method, when forming a choke coil by closely winding each conductive wire, it is necessary to change the thickness of the insulating coating. For this reason, when the line capacitance is increased, there is a problem that the withstand voltage decreases because the thickness of the insulating coating must be reduced. On the other hand, when the line capacitance is reduced, the thickness of the insulating coating must be increased, and consequently the number of windings around the magnetic core is reduced. As a result, it is difficult to secure sufficient inductance. is there. When adjusting the capacitance between the grounds, there is a method of grounding the conductor (C) via a capacitor or a resistor. However, this method requires an external capacitor or resistor for this adjustment. As a result, there is a problem that the size of the distributed constant type filter element is increased and the installation space is increased.
[0006]
The present invention has been made in view of such a problem, and it is possible to adjust line capacitance while securing sufficient inductance and withstand voltage, and furthermore, to adjust capacitance between grounds without externally attaching electronic components. It is an object of the present invention to provide a distributed constant type filter element capable of performing the following.
[0007]
[Means for Solving the Problems]
2. A distributed constant filter element according to claim 1, further comprising: a coil formed by winding a conductive wire; and a ground conductor for generating a ground-to-ground capacitance between the coil and the conductive wire. An element, wherein the coil, a first proximity conductor disposed between the coil and the ground conductor in close proximity to the coil, and disposed between the ground conductor and the first proximity conductor And a laminated body provided with the insulating dielectric material provided on one side of the ground conductor.
[0008]
A distributed constant filter element according to a second aspect is the distributed constant filter element according to the first aspect, wherein the laminated body is disposed on a back side of a surface of the coil facing the first proximity conductor. The second proximity conductor is provided.
[0009]
The distributed constant filter element according to claim 3 is the distributed constant filter element according to claim 1 or 2, wherein the coil is configured by winding the conductive wire in multiple layers, and the laminate includes A third proximity conductor is provided between each layer of the conductor.
[0010]
A distributed constant type filter element according to a fourth aspect is the distributed constant type filter element according to any one of the first to third aspects, wherein the laminate is provided on the other surface side of the ground conductor. ing.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of a distributed constant filter element according to the present invention will be described with reference to the accompanying drawings.
[0012]
First, a distributed constant filter element (hereinafter, also referred to as “filter element”) 1 according to a first embodiment of the present invention will be described with reference to the drawings.
[0013]
As shown in FIG. 2, the filter element 1 includes a magnetic core 2, a ground conductor 3, and a laminate LA. In this case, as shown in FIG. 1, the magnetic core 2 is formed of, for example, a toroidal core having a planar shape formed in a ring shape. As shown in FIG. 2, the grounding conductor 3 is disposed so as to cover almost the entire surface of the magnetic core 2, and as shown in FIG. 3, is grounded via the lead wire A shown in FIGS. You. Further, as shown in FIG. 2, the ground conductor 3 is provided so that the ground conductor 3 does not function as a short ring with respect to a closed magnetic path formed by a current flowing through a coil 6 described later included in the laminated body LA. A notch 3a is formed. In this case, as one example, one notch 3 a is linearly formed on the outer peripheral surface of the magnetic core 2 along the circumferential direction of the magnetic core 2. However, the present invention is not limited to this, and may be formed on the inner peripheral surface or the end surface (the upper end surface or the lower end surface in FIG. 2) of the magnetic core 2, or may be formed in a non-linear shape (for example, a zigzag shape, a curved shape, etc.). May be formed. Furthermore, a plurality may be formed. The ground conductor 3 is formed by attaching a conductive metal foil, plating, and applying a conductive paste.
[0014]
The laminated body LA is provided so as to cover the entire surface of the ground conductor 3 as shown in FIGS. In the present embodiment, the laminate LA includes the dielectric 4, the proximity conductor (first proximity conductor) 5, and the coil 6. In this case, as shown in FIGS. 2 and 3, the dielectric 4 is disposed so as to cover the entire surface of the ground conductor 3 with a substantially uniform thickness using a dielectric material having an insulating property. Insulating dielectric materials include polyethylene, polyimide, polyethylene terephthalate, epoxy resin, glass epoxy, acrylic, vinyl chloride, acetate, ester, polystyrene, polytetrafluoroethylene, silica, mica, rubber, bakelite, and insulation. Paper, various ceramics, various glasses, and the like can be employed. As shown in FIGS. 2 and 3, the proximity conductor 5 is disposed so as to cover the surface of the dielectric 4 in a state of not electrically contacting any other conductor. As shown in FIG. 2, the notch 5a is formed in the proximity conductor 5 so that the proximity conductor 5 does not function as a short ring with respect to a closed magnetic path formed by a current flowing through the coil 6, as in the ground conductor 3. Is formed. The coil 6 is formed by winding a conductive wire (formed of a core wire 7a and a thin insulating coating 7b as shown in FIG. 3) 7 of a thin insulating coating such as an enameled copper wire on the surface of the proximity conductor 5 in a single layer. Is formed. Therefore, the above-described proximity conductor 5 is disposed between the coil 6 and the ground conductor 3 so as to be close to (closely contact with) the coil 6 in the present embodiment.
[0015]
With such a configuration, in the filter element 1, as shown in FIG. 4, a distributed capacitance C1 is formed between the core wire 7a of the conductive wire 7 constituting the coil 6 and the adjacent conductor 5, and A ground-to-ground capacitance C2 is formed between the proximity conductor 5 and the ground (specifically, the grounded ground conductor 3). That is, the filter element 1 constitutes a distributed constant type normal mode filter having the inductance of the coil 6 and the distributed capacitance C1 grounded via the capacitance C2 between the grounds. In this case, the inter-line capacitance of the conductor 7 constituting the coil 6 is defined by the distributed capacitance C1 connected directly in series via the adjacent conductor 5 together with the distributed capacitance C11 formed directly between the lines. Note that the distributed capacitance C11 is also formed between the conductors 7 in the same layer constituting the coil in each of the embodiments described below, but is omitted from the drawings to avoid redundant description. The description is also omitted.
[0016]
In this filter element 1, the laminated body LA, which is formed by laminating the dielectric 4, the adjacent conductor 5, and the coil 6 in this order, is disposed on one surface side of the ground conductor 3, so that the filter element described in the conventional example is provided. Unlike this, since the dielectric 4 is interposed between the ground conductor 3 and the coil 6, the distance between the ground conductor 3 and the coil 6 is increased by the thickness of the dielectric 4. Further, a material having a high withstand voltage can be used as the dielectric 4. Therefore, according to the filter element 1, the withstand voltage can be sufficiently increased as compared with the conventional filter element, so that sufficient safety can be secured. Further, according to the filter element 1, since it is not necessary to increase the thickness of the insulating coating 7b of the conductive wire 7 forming the coil 6, the number of turns of the conductive wire 7 can be increased, and a sufficient inductance can be ensured. Can be realized. Further, in the filter element 1, since the proximity conductor 5 is provided, the distributed capacitance C <b> 1 connected in series with each other via the proximity conductor 5 is an element that defines the inter-line capacitance of the conductor 7 forming the coil 6. It has become. Therefore, by appropriately changing the size of the proximity conductor 5 (the area facing the coil 6) and the like, it is possible to easily adjust the inter-line capacitance of the conductor 7. Further, the value of the capacitance C2 between the grounds can be freely set by changing the material, thickness, etc. of the dielectric 4. In this case, since external electronic components such as a capacitor and a resistor are not required, it is possible to avoid an increase in the size of the filter element 1. Further, the distributed capacitance defined by the distributed capacitance C1 and the ground capacitance C2 can be freely adjusted without using an external electronic component.
[0017]
Next, a filter element 11 according to a second embodiment of the present invention will be described with reference to the drawings. Note that the same components as those of the filter element 1 are denoted by the same reference numerals, and redundant description will be omitted (the same applies to the following embodiments).
[0018]
As shown in FIGS. 5 and 6, the filter element 11 is disposed so as to cover the surface of the coil 6 (the back surface of the coil 6 facing the adjacent conductor 5) in addition to the configuration of the filter element 1. It is configured to include a second proximity conductor 12 (hereinafter, also referred to as “proximity conductor 12”). That is, in the filter element 11, instead of the laminated body LA of the filter element 1, the laminated body LA1 formed by laminating the dielectric 4, the proximity conductor 5, the coil 6, and the proximity conductor 12 in this order is the surface of the ground conductor 3. It is arranged above. In this case, similar to the ground conductor 3 and the proximity conductor 5, the proximity conductor 12 is cut so that the proximity conductor 12 does not function as a short ring with respect to the closed magnetic path formed by the current flowing through the coil 6 (not shown). Are formed.
[0019]
With such a configuration, in the filter element 11, as shown in FIG. 7, the distributed capacitance C <b> 3 is formed between the core wire 7 a of the conductive wire 7 forming the coil 6 and the proximity conductor 12, and An inter-conductor capacitance C4 is formed between the conductor 12 and the adjacent conductor 5. That is, the filter element 11 constitutes a distributed constant type normal mode filter having the combined capacitance of the distributed capacitance C1, the capacitance between grounds C2, the distributed capacitance C3, and the capacitance between conductors C4 and the inductance of the coil 6.
[0020]
In the filter element 11, the configuration from the dielectric 4 to the coil 6 in the laminate LA1 is the same as that of the filter element 1, and the dielectric 4 is disposed between the adjacent conductor 5 and the ground conductor 3. Therefore, according to the filter element 11, the withstand voltage can be sufficiently increased as compared with the conventional filter element. As a result, the same effect as that of the filter element 1 can be obtained, such as sufficient safety can be ensured. be able to. Further, according to the filter element 11, since the laminated body LA1 includes the proximity conductor 12, the line capacitance and the ground capacitance of the conductor 7 forming the coil 6 can be increased. The degree of freedom in designing the characteristics can be further increased.
[0021]
Note that the present invention is not limited to the above embodiments. For example, in each of the filter elements 1 and 11, the coil 6 is formed by winding the conductor 7 by one layer, but the present invention is also applied to a filter element having a coil formed by winding the conductor 7 in multiple layers. be able to. For example, the filter element 21 according to the third embodiment of the present invention shown in FIG. 8 includes a laminate LA2 disposed so as to cover the surface of the ground conductor 3. In this case, the laminated body LA2 is formed by winding the dielectric 4, the proximity conductor 5, and the conductor 7 on the ground conductor 3 in multiple layers (for example, two layers without providing a third proximity conductor 23 described later). The coil 22 formed by turning is laminated in this order. Also in this filter element 21, the configuration from the dielectric 4 to the coil 22 in the laminate LA2 is the same as that of the filter element 1, and the dielectric 4 is disposed between the adjacent conductor 5 and the ground conductor 3. Therefore, the same effect as that of the filter element 1 can be obtained, for example, the withstand voltage can be sufficiently increased and sufficient safety can be secured.
[0022]
As shown in FIG. 8, the filter element 21 has a configuration in which a third proximity conductor 23 (hereinafter, also referred to as “proximity conductor 23”) is provided between each layer of the conductor 7 constituting the coil 22. Can also be adopted. In this case, the laminated body LA2 includes the dielectric 4, the proximity conductor 5, the coil 22, and the proximity conductor 23. The notch (not shown) similar to that of the proximity conductor 5 is formed in the proximity conductor 23 so as not to form a short ring. As shown in FIG. 9, in the filter element 21 in which the proximity conductors 23 are arranged as described above, the distributed capacitance C5 is provided between the conductor 7 a of the conductor 7 and the proximity conductor 23 in each layer (the upper and lower layers in FIG. 9). The conductors 7 are formed in a distributed manner, and the inter-conductor capacitance C4 is formed between the adjacent conductors 5 and 23. As a result, the conductor 7 is formed by winding the conductive wire 7 into a multilayer (for example, the two layers described above) without providing the adjacent conductor 23. In comparison with the coil 22, it is possible to increase both the line-to-line capacitance and the ground-to-ground capacitance with respect to the core wire 7 a located on the upper layer and separated from the ground conductor 3. In this filter element 21, the distribution capacitance C5 between the core wire 7a located in the lower layer and close to the ground conductor 3 and the proximity conductor 23 has a function equivalent to the distribution capacitance C3 in the filter element 11 described above. have.
[0023]
Further, like the filter element 31 according to the fourth embodiment of the present invention shown in FIG. 10, in addition to the configuration of the filter element 21, the surface of the coil 22 ) Can be adopted to further cover the proximity conductor (second proximity conductor) 33 equivalent to the proximity conductor 12 in the filter element 11 so as to cover the filter element 11. In this case, the laminated body LA3 includes the dielectric 4, the proximity conductor 5, the coil 22, the proximity conductor 23, and the proximity conductor 33. In the filter element 31 in which the proximity conductors 33 are arranged as described above, as shown in FIG. 11, a new distributed capacitance C3 is formed between the upper core 7a and the proximity conductors 33, and each distribution capacitance C3 is formed. As a result of the formation of the inter-conductor capacitance C6 between the adjacent conductors 23 and 33, the inter-line capacitance and the inter-ground capacitance for the core wire 7a located on the upper layer and separated from the ground conductor 3 are reduced as compared with the filter element 21. Can be further increased.
[0024]
Furthermore, in each of the filter elements 1, 11, 21, 31 according to each of the above-described embodiments, the dielectric 4, the proximity conductor 5, and the coil 6 (22) are provided on the ground conductor 3 provided on the surface of the magnetic core 2. Are laminated in this order to form the laminates LA, LA1, LA2, and LA3, but the configuration in which the sequence of lamination of the ground conductor 3 and the laminate LA (LA1, LA2, LA3) with respect to the magnetic core 2 is changed. Can also be adopted. Hereinafter, as an example, the filter element 41 in which the stacking order of the ground conductor 3 and the laminated body LA in the filter element 1 is changed will be specifically described. However, it is needless to say that the same can be applied to the other filter elements 11, 21, and 31. This filter element 41 is a filter element according to a fifth embodiment of the present invention. As shown in FIG. 12, a coil 6, a proximity conductor 5, and a dielectric 4 are laminated on a surface of a magnetic core 2 in this order. It comprises a body LA4 and a ground conductor 3 disposed on the surface of the laminated body LA4.
[0025]
This filter element 41 has a structure in which the dielectric 4 is interposed between the ground conductor 3 and the coil 6 in the same manner as the filter element 1, so that the withstand voltage is sufficient compared with the conventional filter element. As a result, the same effect as that of the filter element 1 can be obtained, for example, sufficient safety can be secured.
[0026]
In each of the filter elements 1, 11, 21, 31, and 41 according to each of the above-described embodiments, only one surface of the ground conductor 3 disposed on the surface of the magnetic core 2 has the laminated body LA, LA1, LA1, LA1, or LA1. Although an example in which LA2, LA3, and LA4 are respectively formed has been described, a gap is provided between the magnetic core 2 and the ground conductor 3 in each of the filter elements 1, 11, 21, and 31, and the other laminate LA , LA1, LA2, and LA3 may be employed. In this case, in another laminated body LA, LA1, LA2, LA3 laminated on the other surface side of the ground conductor 3, the laminated body LA disposed on one surface side of the ground conductor 3 with respect to the ground conductor 3 , LA1, LA2, and LA3 are stacked so that the stacking position and the arrangement position of the respective components are symmetrical. Hereinafter, a specific description will be given using the filter element 51 shown in FIG. 13 as an example. The filter element 51 is a filter element according to the sixth embodiment of the present invention. As an example, a gap is provided between the magnetic core 2 and the ground conductor 3 in the filter element 1, and the laminate LA Another laminated body LA having the same configuration as that described above is provided. In this case, each component (dielectric 4, proximity conductor 5, and coil 6) of the laminated body LA provided on one surface (the upper surface in the figure) of the ground conductor 3 and the other of the ground conductor 3 Each component (dielectric 4, proximity conductor 5, and coil 6) of the other laminated body LA disposed on the side of the surface (the lower surface in the figure) is disposed at a symmetrical position with respect to the ground conductor 3. Have been.
[0027]
This filter element 51 also has a structure in which the dielectric 4 is interposed between the ground conductor 3 and each coil 6 in the same manner as the filter element 1, so that the withstand voltage is compared with that of the conventional filter element. As a result, the same effects as those of the filter element 1 can be obtained, for example, sufficient safety can be secured. Further, in the filter element 51, since the two laminated bodies LA and LA are arranged symmetrically with the ground conductor 3 interposed therebetween, as shown in FIG. 14, the coil 6 and the ground conductor 3 in one of the laminated bodies LA are arranged. Is substantially equal to the distributed capacitance C1 between the coil 6 and the ground conductor 3 in the other laminated body LA, and is formed between each adjacent conductor 5 and the ground conductor 3. The capacitance C2 between the grounds is also substantially equal. Therefore, the filter element 51 can be configured as a normal mode filter, and by using the coil 6 of one laminated body LA and the coil 6 of the other laminated body LA separately, the filter element 51 has a distributed constant type. Can be simply configured as a common mode filter.
[0028]
In each of the filter elements 1, 11, 21, 31, and 41 according to each of the above-described embodiments, a single conducting wire 7 is wound around substantially the entire area of the magnetic core 2 to form a single coil. Has been described, but as shown in FIG. 15, by forming the two coils by winding the same number of the two conducting wires 7 on the left and right regions of the magnetic core 2 to form two coils, sufficient inductance and It is possible to realize the filter element 61 as a distributed constant type common mode filter capable of adjusting the line capacitance and the ground capacitance while ensuring sufficient withstand voltage.
[0029]
Further, in each of the filter elements 1, 11, 21, 31, 41, 51, and 61 according to each of the above-described embodiments, an example is described in which a toroidal core is used as the magnetic core 2. However, a bobbin-type or drum-type core, Cores of various shapes such as an EI type core, a pot core, and an RM type core can also be used. Further, as the material of the magnetic core 2, various magnetic materials such as oxide-based ferrite magnetic materials including MnZn ferrite and NiZn ferrite, and metal magnetic materials including iron, nickel, cobalt, and the like can be used. .
[0030]
Furthermore, in each of the filter elements 1, 11, 21, 31, 41, 51, and 61 according to each of the above-described embodiments, an example in which a coil is formed using the conductive wire 7 having a substantially circular cross section has been described. However, the present invention is not limited to this. For example, the present invention can be applied to a filter element in which a coil is formed by winding a tape-shaped conductor on an insulating sheet in a cylindrical shape in a state of being stacked. Further, the present invention can be applied to an air-core coil.
[0031]
【The invention's effect】
As described above, according to the distributed constant filter element of the first aspect, the coil, the first proximity conductor disposed between the coil and the ground conductor in close proximity to the coil, the ground conductor and the first Unlike a conventional filter element, a laminated body having an insulating dielectric material disposed between adjacent conductors is disposed on one surface side of a ground conductor. Can be lengthened by the thickness of the dielectric, so that the withstand voltage can be sufficiently increased, so that sufficient safety can be ensured. Further, according to this distributed constant filter element, it is not necessary to increase the thickness of the insulation coating of the conductor forming the coil, so that the number of turns of the conductor can be increased, and as a result, sufficient inductance can be secured and desired attenuation can be obtained. Characteristics can be realized. Furthermore, according to the distributed constant filter element, the provision of the first proximity conductor allows the distributed capacitances connected in series to each other via the first proximity conductor to have respective line capacitances of the conductors constituting the coil. As a result, the inter-line capacitance of the conductor can be easily adjusted by appropriately changing the size of the first proximity conductor (the area facing the coil) and the like. Also, the value of the capacitance between the grounds can be freely set by changing the material and thickness of the dielectric. Further, since external electronic components such as a capacitor and a resistor can be eliminated, the size of the distributed constant filter element can be avoided. In addition, the distribution capacitance defined by the distribution capacitance and the capacitance between the grounds can be freely adjusted.
[0032]
Further, according to the distributed constant filter element of the second aspect, the second proximity conductor is disposed on the back side of the surface of the coil facing the first proximity conductor, thereby forming a laminated body. As a result, it is possible to further increase the line capacitance and the ground capacitance with respect to the conductor constituting the semiconductor device, thereby further increasing the degree of freedom in designing the attenuation characteristics.
[0033]
Further, according to the distributed constant filter element of the third aspect, in the coil formed by winding the conductor in multiple layers, the third proximity conductor is disposed between each layer of the conductor, thereby forming a laminated body. As a result, a distributed capacitance is formed between the conductive wire and the third proximity conductor in each layer, and an inter-conductor capacitance is formed between the first proximity conductor and the third proximity conductor. It is possible to increase both the line capacitance and the ground capacitance with respect to the conductor located on the upper layer and separated from the first ground conductor.
[0034]
According to the distributed constant filter element of the fourth aspect, the laminated body is also arranged on the other surface side of the ground conductor, so that the two laminated bodies are arranged symmetrically with the ground conductor interposed therebetween. Therefore, the distributed capacitance between the coil and the ground conductor in one laminate and the distributed capacitance between the coil and the ground conductor in the other laminate are approximately equal, and the proximity conductor and the ground conductor in each laminate are As a result, the capacitance between the grounds formed between the two layers becomes almost equal. As a result, a distributed constant type common mode filter can be easily configured by dividing and using the coil of one laminated body and the coil of the other laminated body. can do.
[Brief description of the drawings]
FIG. 1 is a front view showing a configuration of a filter element 1. FIG.
FIG. 2 is a schematic diagram for explaining a cross-sectional structure along a radial direction of a magnetic core 2 in the filter element 1;
FIG. 3 is a cross-sectional view of a main part along a circumferential direction of a magnetic core 2 for illustrating a configuration of a laminated body LA in the filter element 1;
FIG. 4 is an equivalent circuit diagram for explaining a state of formation of a distributed capacitance C1, a ground capacitance C2, and a distributed capacitance C11 in the filter element 1.
FIG. 5 is a front view showing a configuration of a filter element 11;
FIG. 6 is a cross-sectional view of a main part along a circumferential direction of a magnetic core 2 for illustrating a configuration of a laminated body LA1 in the filter element 11;
FIG. 7 is an equivalent circuit diagram for explaining a state of formation of distributed capacitances C1 and C3, capacitance C2 between grounds, and capacitance C4 between conductors in the filter element 11.
8 is a cross-sectional view of a main part of a magnetic core 2 along a circumferential direction for illustrating a configuration of a laminated body LA2 in a filter element 21. FIG.
FIG. 9 is an equivalent circuit diagram for explaining a state of formation of distributed capacitances C1 and C5, a capacitance C2 between grounds, and a capacitance C4 between conductors in the filter element 21.
FIG. 10 is a cross-sectional view of a main part of a magnetic core 2 along a circumferential direction for illustrating a configuration of a laminated body LA3 in the filter element 31.
FIG. 11 is an equivalent circuit diagram for explaining a formation state of distributed capacitances C1, C3, C5, a capacitance C2 between grounds, and capacitances C4, C6 between conductors in the filter element 31.
12 is a cross-sectional view of a main part of a magnetic core 2 along a circumferential direction for illustrating a configuration of a laminated body LA4 in a filter element 41. FIG.
FIG. 13 is a cross-sectional view of a principal part of a magnetic core 2 along a circumferential direction for showing a positional relationship between each of the laminates LA, LA and a ground conductor 3 in a filter element 51.
FIG. 14 is an equivalent circuit diagram for explaining a formation state of a distributed capacitance C1 and a ground capacitance C2 in the filter element 51.
FIG. 15 is a front view illustrating a configuration of a filter element 61.
[Explanation of symbols]
1,11,21,31,41,51,61 Filter element
2 core
3 Ground conductor
4 Dielectric
5,12,23,33 Proximity conductor
6,22 coil
7 conductor
LA, LA1, LA2, LA3, LA4 laminated body

Claims (4)

A coil formed by winding a conductive wire, and a distributed constant filter element including a ground conductor that generates a ground-to-ground capacitance between the coil and the conductive wire,
The coil, a first proximity conductor disposed between the coil and the ground conductor in close proximity to the coil, and an insulation disposed between the ground conductor and the first proximity conductor. A distributed constant filter element, wherein a laminated body including a dielectric material is disposed on one surface side of the ground conductor. 2. The distributed constant filter element according to claim 1, wherein the laminate includes a second proximity conductor disposed on a back side of a surface of the coil facing the first proximity conductor. 3. The coil is configured such that the conductive wire is wound in multiple layers,
3. The distributed constant filter element according to claim 1, wherein the multilayer body includes a third proximity conductor disposed between each layer of the conductive wire. 4. 4. The distributed constant filter element according to claim 1, wherein the laminate is provided on the other surface side of the ground conductor. 5.

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