The present invention disclosed herein relates to a coil having a multi-layer structure, and more particularly, to a coil having a multi-layer structure by which magnetic field generating efficiency may be improved.
Generally, a coil is a component for realizing inductance (L). A coil is produced by covering a highly conductive wire material with an insulating material and then wiring the resultant wire in a ring shape or a spiral shape. A coil plays a role of converting magnetic energy into electric energy. A coil is applied to most electricity-using devices such as a motor, a generator, a transformer, an electromagnet, and a charger. The kinds of a coil include an air-core coil, a core coil, and a troidal coil.
In recent years, a coil having a multi-layer structure has been researched to improve the magnetic field generating efficiency of the coil.
The present invention provides a coil having a multi-layer structure, which improves the magnetic field generating efficiency of the coil.
An embodiment of the present invention provides a coil having a multi-layer structure, the coil including n winding wires (n≧2, n is a natural number) spaced apart from a central axis and wound around the central axis, wherein a first winding wire of the n winding wires is wound to a first height in a direction perpendicular to a reference surface, wherein a second winding wire is wound to a second height lower than the first height in a direction perpendicular to the reference surface, the first winding wire has a first radius from the central axis, and wherein the second winding wire has a second radius from the central axis, the second radius being smaller than the first radius, and the second winding wire is disposed in the first winding wire.
In an embodiment, the first and second winding wires may have the same thickness.
In an embodiment, directions in which the n winding wires are wound may be identical.
In an embodiment, the n winding wires may be wound in a ring shape or a spiral shape around the central axis.
In an embodiment, intervals between the n winding wires may be regular.
Another embodiment of the present invention provides a coil having a multi-layer structure, the coil including a plurality of winding wires respectively wound in a ring shape or a spiral shape around a central axis and having different radii from the central axis, wherein the plurality of winding wires are sequentially disposed according to the radii in a direction which becomes farther from the central axis, and wherein heights of the plurality of winding wires wound in a direction perpendicular to a reference surface become greater as the winding wires are disposed further from the central axis.
In an embodiment, heights of the winding wires wound in a direction perpendicular to the reference surface may become greater as the winding wires are disposed father from the central axis.
In an embodiment, the winding wires may have the same thickness.
In an embodiment, directions in which the winding wires are wound may be identical.
In an embodiment, the winding wires may be wound in a ring shape or a spiral shape around the central axis.
According to an embodiment of the present, magnetic field generating efficiency of the coil may be improved.
Structural or functional descriptions, which are specified with reference to embodiments according to the inventive concept set forth herein are merely provided to describe embodiments of the inventive concept. Embodiments of the inventive concept may, however, be embodied in different forms and should not be constructed as limited to the embodiments set forth herein.
Numerous modifications and aspects can be applied to embodiments of the inventive concept. Thus, exemplary embodiments will be described below in more detail with reference to the accompanying drawings. However, embodiments of the inventive concept are not limited to particular aspects. Rather, all modifications, equivalents, and substitutes involved in the ideas and art of the present invention are included.
It will be understood that when a component is referred to as being “connected” or “in contact” with another component, it can be directly connected or in contact with the other component, or another component may also be provided therebetween. On the other hand, it will be understood that when a component is referred to as being “directly connected” or “directly in contact” with another component, no intervening component is disposed therebetween. Other expressions describing relationships between components, such as “between” and “directly between” or “adjacent to” and “directly adjacent to” should be also understood likewise.
The present invention relates to a coil having a multi-layer structure and, more specifically, to a coil having a multi-layer structure by which magnetic field generating efficiency may be improved. Hereinafter, embodiments of the present invention will be described in details with reference to the accompanying drawing so that those skilled in the art of the present invention could easily carry out the technical ideas of the present invention.
Referring to
Referring to
Here, B represents magnetic flux density, a represents a radius, I represents an electric current, μ0 represents vacuum permeability, and z represents a distance from the reference surface.
Referring to Equation 1, the magnetic field in the central part of the coil 10 illustrated in
As for the coil 10 illustrated in
Coils in
First, referring to
Each of the winding wires 110 to 160 has a radius from the central axis (I). For instance, the winding wire 110 may have the largest radius. The winding wires 110 to 160 may have smaller radius towards a first direction. The first direction may indicate a direction from the winding wire 110 to the winding wire 160. In another aspect, the first direction may indicate a direction that is parallel to the reference surface (z=0). That is, the winding wires 110 to 160 may be sequentially disposed from the central axis (I) according to radii thereof. The winding wires 110 to 160 may be disposed to be spaced particular intervals apart from each other. The intervals between the winding wires 110 to 160 may be regular but are not limited thereto. Accordingly, the winding wires 110 to 160 may form a coil having a multi-layer structure.
The winding wires 110 to 160 may be wound in a ring shape or a spiral shape around the central axis (I). The winding wires 110 to 160 may be wound towards a second direction. The second direction, for instance, may indicate a direction that is parallel to the central axis (I). In another aspect, the second direction may indicate a direction that is perpendicular to the reference surface (z=0). The winding wires 110 to 160 may be wound, for example, in the same direction (for instance, a clockwise direction).
The winding wires 110 to 160 may be designed such that heights of the winding wires wound in the second direction gradually decrease towards the first direction. For instance, heights of the winding wire 120, winding wire 130, winding wire 140, winding wire 150, and winding wire 160, which are wound in the second direction, may respectively lower than those of the winding wire 110, winding wire 120, winding wire 130, winding wire 140, and winding wire 150. That is, the inside of the coil 100 may be understood to have a reversed pyramid shape.
Referring to
The winding wires 210 to 260 may be sequentially disposed on the central axis (I) according to radii thereof. The winding wires 210 to 260 may be designed such that heights of the winding wires wound in the second direction gradually decrease towards the first direction. For instance, heights of the winding wire 220, winding wire 230, winding wire 240, winding wire 250, and winding wire 260, which are wound in the second direction, may be lower than those of the winding wire 210, winding wire 220, winding wire 230, winding wire 240, and winding wire 250.
A difference in a height between the winding wires 210 to 260 that are wound in the second direction may be larger than a difference in a height between the winding wires 110 to 160 that are wound in the second direction. That is, it may be understood that the inside of the coil 200 has a stair shape.
Referring to
Referring to
A coil made of a winding wire having a small radius from the central axis (I) has a shorter effective length than a coil made of a winding wire having a large radius from the central axis (I). For instance, an effective length of a coil made of a winding wire having a radius of 10 mm from the central axis (I) is approximately 0.05 m. An effective length of a coil made of a winding wire having a radius of 50 mm from the central axis (I) is approximately 0.16 m.
That is, a coil made of a winding wire having a small radius from the central axis (I) has a smaller influence on an increase in a magnetic field as a length of the coil becomes longer.
The longer the length of the coil is, the larger the resistance and inductance of the coil are. Increases in the resistance and inductance of the coil results in a decrease in an electric current under a particular voltage and rather hinders the generation of a magnetic field. Accordingly, it may be understood that, in the case of a coil having a multi-layer structure, a winding wire having a small radius wound inside thereof may be unhelpful to the generation of a magnetic field compared to a winding wire having a large radius wound outside thereof. Moreover, the winding wire having a small radius wound inside thereof may result in an increase in the resistance and inductance of the coil, which may become a factor of hindering the heat of the coil from being released.
Referring to
Accordingly, an influence of a coil made of a winding wire having a small radius from the central axis (I) on a magnetic field generated by a coil having a multi-layer structure may be reduced. That is, the magnetic field generating efficiency of a coil having a multi-layer structure may be improved. This may means that when the same voltage is applied to the coils 100 and 200, the strength of a magnetic field and/or the magnitude of an induced current is/are increased.
Referring to
The first coil 1100 may receive a voltage from the outside and generate a magnetic field. An eddy current may be generated on the measuring target 1300 due to the generated magnetic field. The eddy current may decrease towards the inside of the measuring target 1300. The generated magnetic field may be transferred to the second coil 1200 by passing through the measuring target 1300. The strength of the magnetic field may be varied (ex. reduced) while passing through the measuring target 1300. The first coil 1100 may have the same structure and function as the coils 100 and 200 described in
The second coil 1200 may detect the magnetic field generated from the first coil 1100. The second coil 1200 may detect the magnetic field generated from the first coil 1100 as the strength of an induced voltage or magnetic field. A thickness of the measuring target 1300 may be determined according to the detected strength of an induced voltage or magnetic field. This is because the magnetic field generated from the first coil 1100 may be differently changed (ex. attenuated) depending on a material and/or a thickness of the measuring target 1300 while being transferred to the second coil 1200. The second coil 1200, for instance, may be replaced by a hall sensor or a giant magnetic resistive (GMR) sensor.
The measuring target 1300 may be, for example, a metal plate such as aluminum and steel sheets.
Referring to
Here, Vex is an external voltage applied to the first coil 1100, Iex is an electric current passing through the first coil 1100, R is equivalent resistance, and L is equivalent inductance.
Referring to
Referring to
Referring to
Referring to
Although illustrative embodiments have been described in the detailed description of the present invention, numerous other modifications can be devised within the scope and technical idea of the present invention. Thus, the scope of the present invention shall not be restricted or limited by the foregoing detailed description, and is to be determined by the broadest permissible interpretation of the following claims and their equivalents.
Number | Date | Country | Kind |
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10-2012-0155022 | Dec 2012 | KR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/KR2013/012303 | 12/27/2013 | WO | 00 |