JP6599265B2 - Non-contact power feeding device - Google Patents

Description

  The present invention relates to a non-contact power feeding device. That is, it is related with the non-contact electric power feeder for cooking which supplies electric power to an electric cooking container non-contactingly.

《Technical background》
Various electric cooking containers are used in kitchens and dining tables. For example, a mixer, a hot water pot, an electric heat pot, a coffee maker, an electric heat pot, etc. .
These electric cooking containers are usually connected to an outlet through a plug with a cord and are supplied with power. However, it has been pointed out that such a wiring connection method is troublesome because it easily disturbs a kitchen or a table, and it is easy to cause trouble in washing the electric cooking container itself.

<Conventional technology>
In view of such a situation, a technique using a non-contact power feeding device (WPT) (Wireless Power Transfer) has been developed.
For example, as shown in FIG. 6, the power receiving coil 4 of the power receiving side circuit disposed on the electric cooking container 3 side from the power transmitting coil 2 of the power transmitting side circuit disposed on the power supply stand 1 on the table A side of the kitchen or dining table. In addition, cordless, that is, an electric contactless power supply technology has been developed and used. A technology using the non-contact power feeding device 5 has been developed and used.
That is, the power transmission coil 2 of the power transmission side circuit is energized with an exciting current from an AC power source, and thus a magnetic path of magnetic flux is formed and electromagnetically coupled with the power receiving coil 4 positioned vertically opposite to each other. Thus, electric power is supplied to the load of the power receiving side circuit.
In the non-contact power feeding device 5 for cooking, the electric cooking vessel 3 is fed with cordless power due to such mutual induction action of electromagnetic induction. And in this non-contact electric power feeder 5, like the normal non-contact electric power feeder, the power transmission coil 2 and the receiving coil 4 consisted of the symmetrical structure of the same diameter which makes a pair up and down.

As such a non-contact electric power feeder 5, what was shown in the following patent documents 1 and 2 is mentioned, for example.
JP, 2015-231473, A JP 2013-016497 A

However, the following problems have been pointed out as problems for the conventional non-contact power supply device 5.
The conventional non-contact power feeding device 5 for cooking is composed of an individual method for each electric cooking container 3. Mixer, hot water pot, electric heat-insulating pot, etc. Etc., the electric power feeder 1 provided with the power transmission coil 2 was used for every various electric cooking containers 3.
That is, in each electric cooking vessel 3, loads corresponding to the respective uses are used, and power receiving coils 4 corresponding to the respective loads are used. Accordingly, the size, diameter, type, and the like of the power receiving coil 4 are various, and the power transmitting coil 2 having a symmetrical structure that forms a pair with the power receiving coil 4 in the vertical direction is similarly varied. The power supply stand 1 of the power transmission coil 2 also varies.
Therefore, on the table A of the kitchen or the dining table, it is necessary to use the power transmission coil 2 corresponding to each of them depending on the type of the electric cooking container 3 and the power receiving coil 4 that are required. It was. The power supply stand 1 provided with such a power transmission coil 2 was placed on the table A.
Therefore, the following problems have been pointed out regarding the power transmission coil 2 and the power supply stand 1 for the conventional non-contact power supply device 5 for cooking.
-It is properly used according to the type and size of the electric cooking container 3, which is inconvenient and troublesome.
-There are many types, which may interfere with the kitchen and dining table, which is also inconvenient.
-Depending on the type and size of the electric cooking container 3, it is used for individual use, which increases the production cost.

<< About the present invention >>
In view of such a situation, the non-contact power feeding device of the present invention has been made to solve the above-described problems of the prior art.
In the present invention, firstly, electric cooking containers of various sizes can be fed regardless of where they are placed on the feeding table, and secondly, they are convenient and excellent in cost, and thirdly, feeding efficiency. It is an object of the present invention to propose a non-contact power feeding device that suppresses the occurrence of a lowered portion, reduces the external diffusion of a magnetic field, and fourthly prevents the occurrence of a feeding null point or the like.

<About each claim>
The technical means of the present invention for solving such a problem is as follows, as described in claim 1 of the claims.
This non-contact power feeding device is based on the mutual induction action of electromagnetic induction, and the power receiving coil of the power receiving side circuit disposed on the electric cooking container side from the power transmitting coil of the power transmitting side circuit disposed on the power feeding table side of the kitchen or table. The present invention also relates to a non-contact power feeding device for cooking that supplies power in a non-contact manner.
The power transmission coil is wound in a large loop shape. The power receiving coil is wound in a loop shape having a smaller diameter than the power transmitting coil.
The power receiving coil is positioned corresponding to the power transmission coil in a vertical relationship during power feeding, and is placed in the magnetic field position of the power transmission coil.
The power transmission coil is composed of a planar assembly of an even number of unit coils and has a multipolar structure. Each of the unit coils has a setting in which the direction of the current and the direction of the magnetic field are reversed between the adjacently arranged units.

Accordingly, the power transmission coil is formed with a wide magnetic field for each unit coil, and the power receiving coil is located near the coil wire having a strong magnetic force of each unit coil. Demonstrate the function.
At the same time, the power transmission coil has a large diameter, and due to a large dimensional difference from the small diameter power receiving coil, a large amount of magnetic field is likely to be externally diffused. Based on the setting in which is reversed, the function of reducing the external diffusion of the magnetic field is exhibited by canceling the overlapping portion between adjacent magnetic fields.

Furthermore, if the power receiving coil is located across the unit coils that are adjacently disposed with the magnetic field direction of the power transmitting coil reversed, there is a possibility that electromagnetic coupling may become difficult.
On the other hand, the power receiving coil is composed of a three-dimensional assembly of three-way coils of an X coil, a Y coil, and a Z coil. The X coil is disposed on the left and right side surfaces of the electric cooking container, the Y coil is disposed on the front and rear side surfaces of the electric cooking container, and the Z coil is disposed on the bottom surface of the electric cooking container. Has been.
Accordingly, even in the above case, at least one of the X coil, the Y coil, and the Z coil exhibits an electromagnetic coupling function with the unit coil of the power transmission coil.

<About the action>
Since the present invention comprises such means, the following is achieved.
(1) When feeding, an electric cooking container is placed on the feeding table.
(2) Therefore, the small receiving coil on the electric cooking container side is placed in the magnetic field position corresponding to the large transmitting coil on the feeding table side in a vertical relationship.
(3) In this way, the power transmission coil and the power reception coil are electromagnetically coupled, and electric power is supplied from the feeding table side to the electric cooking vessel side by the magnetic field resonance coupling method based on the mutual induction action of electromagnetic induction.
(4) Then, according to this non-contact electric power feeder for cooking, it becomes like the following 1st-4th.
First, because different diameter coils are used for the power transmission coil and the power reception coil, the electric cooking container and the power reception coil can be placed anywhere on the power supply table and the power transmission coil regardless of their types and sizes. The power can be supplied.
Second, it is easy to use and has a simple structure.
Thirdly, since the power transmission coil has an even multipolar structure and the direction of the magnetic field is reversed between adjacent unit coils, the following is obtained.
(A) The occurrence of a decrease in power supply efficiency is suppressed, a high coupling coefficient is obtained on the whole and on average, and a situation in which a difference occurs in the coupling coefficient is solved.
(B) Electromagnetic fields radiated to the vicinity are weakened by overlapping and canceling each other, and external diffusion of electromagnetic waves is reduced.
Fourth, since the power transmission coil has a multipolar structure and the power reception coil is a three-dimensional coil of X, Y, Z coils, the electric cooking container and the power reception coil are each unit coil of the power transmission coil. Even when it is located between them, one of the coils is electromagnetically coupled to the unit coil of the power transmission coil. Accordingly, a reduction in coupling coefficient, particularly generation of a feeding null point is avoided.
(5) Therefore, the present invention exhibits the following effects.

<< First effect >>
First, it is possible to supply power regardless of where the large and small electric cooking containers are placed on the power supply table.
In the non-contact power feeding device for cooking according to the present invention, the electric cooking container can be powered regardless of its type and size, regardless of its type and size. Regardless of the type and size of the power receiving coil, the power receiving coil can be fed anywhere on the power transmitting coil.
Unlike the above-described conventional non-contact power feeding device, it is not necessary to use various types of power transmission coils and power feeding stands for individual use according to the type and size of the electric cooking container. One power transmission coil and power supply table can be used for various power receiving coils and various electric cooking containers.

<< Second effect >>
Secondly, it is convenient and excellent in cost.
As described above, the non-contact power feeding device for cooking according to the present invention is compatible with various power receiving coils and various electric cooking containers with a single power transmission coil and power feeding table.
Unlike the conventional example described above, it is not necessary to use the power supply stand and the power transmission coil individually and exclusively according to the types and sizes of the electric cooking container and the power reception coil. Therefore, it can be used easily, and it is convenient and troublesome. In addition, as in the conventional example, there are many types of power transmission coils and power supply stands, and the situation that obstructs the kitchen and the table is also eliminated.
Furthermore, it is not necessary to use a power transmission coil or a power supply stand individually dedicated to the type and size of the electric cooking vessel. A single power transmission coil or power supply table may be used, which simplifies the configuration and reduces the manufacturing cost accordingly.

《Third effect》
Thirdly, the occurrence of a decrease in power supply efficiency is suppressed, and the external diffusion of the magnetic field is also reduced.
In the non-contact power feeding device for cooking according to the present invention, the power transmission coil has a multipolar structure, and the direction of the magnetic field is reversed between adjacent unit coils, so that the following (a) and (b) are obtained. .
(A) Occurrence of a portion where the power feeding efficiency is reduced is suppressed. As in the case where the power transmission coil is not multipolarized, the situation in which a difference occurs in the coupling coefficient depending on whether the power reception coil is located near the coil wire of the power transmission coil is eliminated. Overall, a high coupling coefficient is obtained on average, and the power supply efficiency is improved.
(B) External diffusion of the magnetic field is reduced. The electromagnetic fields that are formed in opposite directions from the even number of unit coils of the power transmission coil and are externally radiated to the vicinity are weakened by overlapping each other. Due to the magnetic field confinement by such a power transmission coil, electromagnetic waves that are diffused outside are greatly reduced.
As in the case where the power transmission coil is not multipolarized, the situation where a large amount of electromagnetic waves are externally diffused is eliminated based on the dimensional difference from the small diameter receiving coil, and the risk of causing electromagnetic interference around the neighborhood is prevented. Is done.

<< 4th effect >>
Fourth, the occurrence of a power feeding null point or the like is prevented.
That is, in the non-contact power feeding apparatus for cooking according to the present invention, the power transmission coil has a multipolar structure, and the power reception coil is three-dimensionally configured with three-directional coils of X, Y, and Z. Become.
In the case of a planar power receiving coil that is not three-dimensional, the coupling coefficient decreases if the direction of the induced magnetic field of the power transmission coil having a multipolar structure is located across adjacent unit coils. In particular, there is a fear that a power supply null point may occur where the coupling coefficient becomes zero and power supply becomes impossible.
In contrast, since the three-way coil is used, at least one of the electric cooking container and the power receiving coil is electromagnetically coupled to the power transmitting coil regardless of the position and direction of the electric cooking container and the power receiving coil. Occurrence of a feeding null point at which the coupling coefficient becomes zero and power feeding becomes impossible is avoided.
As described above, the effects exerted by the present invention are remarkably large, such as all the problems existing in this type of prior art are solved.

About the non-contact electric power feeder which concerns on this invention, it uses for description of the form for implementing invention, and shows a 1st example (premise example). And (1) figure is a plane explanatory view of a power transmission coil and a power receiving coil, (2) figure is also the same plane explanatory drawing, (3) figure is the front explanatory figure, and (4) figure is the front of the whole It is explanatory drawing. A first example (premise example) will be shown for explanation of the mode for carrying out the invention. (1) is a block diagram of the configuration, and (2) is a basic circuit diagram. It uses for description of the form for implementing this invention, and shows the 2nd example (power transmission coil). (1) is an explanatory plan view of the power transmission coil, (2) is an explanatory plan view of the power transmission coil and the receiving coil, and (3) is an explanatory plan view of another example of the transmission coil. A third example (a power receiving coil) is shown for explanation of the embodiment for carrying out the invention. (1) is an explanatory plan view of the power receiving coil, (2) is an explanatory front view, (3) is an explanatory bottom view, and (4) is an overall front explanatory view, (5) FIG. 5 is an explanatory bottom view of a power transmission coil and a power reception coil. A third example (a power receiving coil) is shown for explanation of the embodiment for carrying out the invention. FIG. 1A is a circuit diagram of an example of a power receiving side circuit, and FIG. 2B is a circuit diagram of another example of the power receiving side circuit. It is a front explanatory drawing for description of a prior art example.

Hereinafter, embodiments for carrying out the present invention will be described in detail.
<< About the non-contact power feeding device 6 >>
First, a non-contact power feeding device 6 which is a premise of the present invention will be generally described with reference to FIG. 1 (3), FIG. (4), FIG. 2 (1), (2) and the like. Keep it.
The non-contact power feeding device 6 for cooking is arranged on the electric cooking container 9 side from the power transmission coil 8 of the power transmission side circuit 7 arranged on the table A side of the kitchen or the table based on the mutual induction action of electromagnetic induction. The power is supplied to the power receiving coil 11 of the power receiving side circuit 10 in an electrically non-contact manner.

These will be further described in detail. First, the primary power transmission side circuit 7 is disposed on the power supply table 12 on the table A side of the kitchen or the table. The power supply table 12 may be integrally incorporated in the table A, but may be placed as a separate body. The secondary power receiving circuit 10 is disposed on the electric cooking container 9 side.
Examples of the electric cooking container 9 include a mixer, a hot water pot, a coffee maker, a steamer, a bread maker, an electric heat pot, an electric heat cup, an electric heat pot, an electric heat dish, an electric heat pot, etc. Various other things are possible. Various cooking utensils that heat, cook, prepare, keep warm, and cool food and drink are targeted.
The electric cooking container 9 is placed on the power supply table 12 in use. Accordingly, the power receiving coil 11 of the power receiving side circuit 10 on the electric cooking container 9 side is placed in a corresponding position on the power transmitting coil 8 of the power transmitting side circuit 7 on the power feeding table 12 side.
The power receiving coil 11 and the power transmitting coil 8 are wirelessly, that is, electrically non-contact, and correspond to each other via a resin material that forms the bottom of the electric cooking container 9 and the top of the power feeding table 12. It is located through a non-magnetic, non-conductive, high electrical resistance material that is not magnetized and not affected by the magnetic field.

In the primary side power transmission side circuit 7, the power transmission coil 8 is connected to a high frequency power source 13. The high-frequency power source 13 includes an inverter for converting a frequency into a high frequency and the like, and energizes a high-frequency alternating current of, for example, about several kHz to several tens kHz to several hundred kHz toward the power transmission coil 8.
In the secondary power receiving circuit 10, the power receiving coil 11 is connected to a load 14. In the illustrated example, the output from the power receiving coil 11 is supplied to the load 14 after AC is converted into DC by the converter 15. Of course, when the load 14 is not a direct current resistance such as a motor as in the illustrated example but an alternating current resistance such as a heater, the load 14 is supplied as it is.
The power transmission side circuit 7 is provided with a parallel capacitor 16 for parallel resonance, and the power receiving side circuit 10 is also provided with a parallel capacitor 17 for parallel resonance. The power transmission coil 8 and the parallel capacitor 16, and the power reception coil 11 and the parallel capacitor 17 form a resonance circuit, respectively, and the amount of power supply is increased by resonance.
Although it is possible to use a series capacitor for series resonance, it is possible to use only parallel capacitors 16 and 17 for parallel resonance or use only a series capacitor for series resonance as a resonance circuit. .
The resonance frequencies of both parallel resonance circuits are set to be equal, and the power supply frequency of the high frequency power supply 13 of the power transmission side circuit 7 is also equal to the resonance frequency.

The mutual induction effect of electromagnetic induction is as follows. During power feeding, the power transmission coil 8 and the power reception coil 11 are positioned correspondingly with a non-contact gap. And it is publicly known and publicly used to generate an induced electromotive force in the power receiving coil 11 by forming magnetic flux in the power transmitting coil 8 and to supply power from the power transmitting coil 8 to the power receiving coil 11.
That is, by applying and energizing a power feeding AC from the high frequency power source 13 to the power transmission coil 8 as a resonance current and an excitation current, a self-induced electromotive force is generated and a magnetic field is generated around the power transmission coil 8, and a magnetic flux φ is generated in the coil. It is formed in a direction perpendicular to the surface. Then, the formed magnetic flux φ penetrates through the power receiving coil 11 to generate an induced electromotive force and induce a magnetic field.
Using the magnetic field induced in this way, it is possible to supply power of several kW or more to several tens kW to several hundred kW. The magnetic circuit of magnetic flux φ on the power transmission coil 8 side and the magnetic circuit of magnetic flux φ on the power receiving coil 11 side are electromagnetically coupled with each other by forming a magnetic circuit of magnetic flux φ, that is, a magnetic path φ.
In the non-contact power feeding device 6, non-contact power feeding is performed based on such electromagnetic induction mutual induction action, but a magnetic resonance coupling method (magnetic resonance method) is also used. That is, as described above, by arranging the resonance frequency and the power supply frequency to be uniform, a magnetic field resonance (magnetic field resonance) phenomenon occurs between the power transmission coil 8 and the power reception coil 11, thereby further expanding the non-contact gap. .
About the non-contact electric power feeder 6, the general description is as above.

<< About the first example (premise example) >>
Hereinafter, the non-contact electric power feeder 6 for cooking of this invention is demonstrated. First, the present invention will be described with reference to a first example (premise example) shown in FIGS.
In the non-contact power feeding device 6, different diameter coils are employed, the power transmission coil 8 is wound in a large loop shape, and the power receiving coil 11 is wound in a loop shape smaller in diameter than the power transmission coil 8. It has been turned.
The power receiving coil 11 is positioned corresponding to the power transmission coil 8 in an up-and-down relationship during power feeding, and is placed in the magnetic field position of the power transmission coil 8.

These will be further described in detail. The power transmission coil 8 and the power reception coil 11 are wound in a spiral annular shape, a rectangular annular shape, other annular shapes, and a loop shape.
The power transmission coil 8 is configured to be larger than the power reception coil 11. That is, the winding diameter of the power transmission coil 8 is about several times the winding diameter of the power receiving coil 11, for example, about 5 to 6 times, but may be about 2 to 20 times.
The winding diameter of the power receiving coil 11 varies depending on the type and size of the target electric cooking vessel 9 (see FIG. 1 (4)). It covers an area where multiple items can be placed with a margin. That is, the winding diameter of the power transmission coil 8 is set to be much larger than the winding diameter of the power reception coil 11.
It is most efficient in terms of power supply that the winding axis of the power transmission coil 8 and the winding axis of the power reception coil 11 are parallel as shown in the figure.

As described above, the power transmission coil 8 is incorporated and disposed below the power supply table 12. The power receiving coil 11 is incorporated and disposed on the lower side and the bottom side of the electric cooking vessel 9. Therefore, according to the diameter relationship between the power transmission coil 8 and the power reception coil 11 described above, the power supply table 12 is configured to be much larger than the electric cooking container 9.
When the electric cooking container 9 is placed on the power supply table 12 during power feeding, the small diameter receiving coil 11 on the electric cooking container 9 side moves up and down relative to the large power transmitting coil 8 on the power feeding table 12 side. Corresponding position under close contact non-contact gap distance. The electric cooking vessel 9 is appropriately selected as necessary, and one or a plurality of the electric cooking vessels 9 are placed on the power supply table 12.
In the non-contact power feeding device 6, the small diameter power receiving coil 11 is placed on the large diameter power transmitting coil 8, that is, in the winding area of the power transmitting coil 8 and in the magnetic field position of the power transmitting coil 8. Accordingly, both are electromagnetically coupled and power is supplied.

<< About the second example (power transmission coil) >>
Next, the second example (power transmission coil) shown in FIG. 3 will be described.
This non-contact power feeding device 6 is characterized by a power transmission coil 8. That is, the power transmission coil 8 has a multipolar structure and a planar assembly of a plurality of unit coils 18. Each unit coil 18 has a setting in which the direction of the current and the direction of the magnetic field are opposite to each other arranged adjacent to each other.
Therefore, the power transmission coil 8 exhibits a function of suppressing the occurrence of a decrease in power supply efficiency due to the magnetic field formed for each unit coil 18. Further, the function of reducing the external diffusion of the magnetic field is exhibited by canceling the overlapping portion between adjacent magnetic fields.

These will be further described in detail. First, the following points (a) and (b) are pointed out for the non-contact power feeding device 6 of the first example (premise example) described above (see FIG. 1).
(A) When the power receiving coil 11 is located near the center a of the power transmitting coil 8 and when it is located near the periphery b, the coupling coefficient of both electromagnetic couplings is greatly different by a difference of several times or more. There was an indication that.
For example, when the diameter of the power transmission coil 8 and the power reception coil 11 is 6: 1, a difference of about 5 times occurs in the coupling coefficient. When the power receiving coil 11 is located near the center a, that is, when the power receiving coil 11 is located away from the coil wire 19 of the power transmission coil 8, the magnetic force from the coil wire 19 is weak and the power feeding efficiency is poor. On the other hand, when it was located near the periphery b, that is, near the coil wire 19 of the power transmission coil 8, the magnetic force from the coil wire 19 was strong and the power supply efficiency was good.
As described above, in the non-contact power feeding device 6 of the first example (premise example) of FIG. 1, the coupling coefficient and the power feeding efficiency are not uniform and unevenness is likely to occur.
(B) In the non-contact power feeding device 6 of the first example (premise example), it was pointed out that a large amount of electromagnetic waves are easily diffused outside.
That is, since there is a large diameter difference and dimensional difference between the power transmission coil 8 and the power reception coil 11, there is a possibility that electromagnetic waves are externally diffused with high strength by the electromagnetic field formed by the power transmission coil 8 during power feeding. The electromagnetic field formed by the power transmission coil 8 may be radiated to the outside in a large amount without being electromagnetically coupled to the power reception coil 11.

On the other hand, in the non-contact power feeding device 6 of the second example (power transmission coil) shown in FIG. 3, first, the power transmission coil 8 has a multipolar structure with an even number of magnetic poles.
That is, the power transmission coil 8 is an aggregate of even-numbered unit coils 18 wound in a loop. The example shown in FIGS. 3A and 3B is an assembly of eight unit coils 18 in which a circle is equally divided radially. The example shown in FIG. 3C is an assembly of eight square unit coils 18 that are equally divided.
And about such each unit coil 18, the direction of the electric current of each coil wire 19 is set reversely between the mutually adjacently arranged.

<< Function of Power Transmission Coil 8 of Second Example (Power Transmission Coil) >>
The power transmission coil 8 of the non-contact power feeding device 6 of the second example (power transmission coil) of FIG. 3 exhibits the following functions (a) and (b) by adopting the multipolar structure of each unit coil 18. .
(A) The above-described multipolar structure exhibits the function of suppressing the occurrence of a decrease in power supply efficiency.
Since the power transmission coil 8 is not multipolarized as in the first example (premise example) described above, the situation in which the coupling coefficient varies depending on the position of the power reception coil 11 is eliminated.
As much as the power transmission coil 8 is multipolarized by each unit coil 18, that is, the generated magnetic force is set wider by the amount of each unit coil 18. As a result, the power receiving coil 11 is located more near the coil wire 19 of the unit coil 18, so that the coupling coefficient increases uniformly and uniformly on the whole and on average, and the power feeding efficiency is improved. .

(B) The multipolar structure described above exhibits the function of reducing magnetic field external diffusion.
As in the first example (premise example) described above, the possibility that electromagnetic waves are strongly diffused externally in a large amount in the electromagnetic field formed by the power transmission coil 8 during power feeding is reduced.
That is, the direction of the current is reversed between the unit coils 18 of the power transmission coil 8 that are arranged adjacent to each other.
Accordingly, between the unit coils 18 arranged adjacent to each other, the N pole and the S pole of the magnetic poles are reversed, and the directions of the formed high-frequency electromagnetic fields (AC fluctuation electromagnetic fields) are also reversed. In the example of FIG. 3A, the broken line display indicates the direction of current flow, the high frequency electromagnetic field in the positive direction is clockwise, and the high frequency electromagnetic field in the negative direction is counterclockwise.
Therefore, the high-frequency electromagnetic field radiated to the vicinity is canceled by overlapping and canceling in the vicinity, and the density is greatly reduced and weakened. As a result, the intensity of the electromagnetic wave diffused to the vicinity is greatly reduced.
About the 2nd example (power transmission coil), it is as above.

<< About the third example (receiving coil) >>
Next, the non-contact power feeding device 6 of the third example (power receiving coil) shown in FIGS. 4 and 5 will be described.
This non-contact power feeding device 6 has a feature in the power receiving coil 11. First, as a premise, the power transmission coil 8 has the multipolar structure of the second example (power transmission coil) described above.
At the same time, the power receiving coil 11 is constituted by a three-dimensional assembly of three-way coils of an X coil 20, a Y coil 21, and a Z coil 23.
The X coil 20 is disposed on the left and right side surfaces of the electric cooking vessel 9. The Y coil 21 is disposed on the front and rear side surfaces 24 of the electric cooking vessel 9. The Z coil 22 is disposed on the bottom surface 25 of the electric cooking vessel 9.

These will be further described in detail. First, the following point is pointed out about the non-contact electric power feeder 9 of the 2nd example (power transmission coil) mentioned above.
Depending on the position where the electric cooking container type 9 and the power receiving coil 11 are placed, there is a possibility that a power supply null point may occur (see FIG. 3B).
That is, when the power receiving coil 11 is positioned inside the unit coil 18 of the power transmitting coil 8 during power feeding, a high coupling coefficient is obtained. On the other hand, when the power receiving coil 11 is located at the boundary d, the coupling coefficient is lowered, and the coupling coefficient becomes zero, which makes it impossible to feed power.
That is, when the power receiving coil 11 is positioned across the adjacent unit coils 18 of the power transmitting coil 8, the directions of the magnetic fields induced and formed by the adjacent unit coils 18 are opposite, so that the electromagnetic coupling between them is hindered Become.
In particular, as shown in the figure, when the center of the power receiving coil 11 is located on the boundary d between the adjacent unit coils 18, the direction of the magnetic field is reversed by half for the power receiving coil 11, and the magnetic fields cancel each other and become zero. . Therefore, the electromagnetic coupling between the power transmission coil 8, that is, the unit coil 18 and the power receiving coil 11 is not established, and the coupling coefficient becomes zero.

Therefore, in the non-contact power feeding device 6 of the third example (power receiving coil) shown in FIG. 4, a three-way coil is three-dimensionally adopted as the power receiving coil 11.
The power receiving coil 11 so far consists of a single coil wound in a plane, whereas in this third example (power receiving coil), the three directions of the X coil 20, the Y coil 21, and the Z coil 22 are used. Coils are used in combination in three dimensions.

That is, the X coil 20 is disposed on one side (illustrated example) or both sides of the left and right side surfaces 23 of the electric cooking vessel 9. The Y coil 21 is disposed on one side (illustrated example) or both sides of the front and rear side surfaces 24 of the electric cooking vessel 9. The Z coil 22 is disposed on the bottom surface 25 of the electric cooking vessel 9. If the X and Y coils 20 and 21 are disposed on both sides, the power supply efficiency is further improved. In the figure, reference numeral 26 denotes a top surface.
As a representative example, as a three-dimensional orthogonal coordinate system, the front and rear side surfaces 24 of the electric cooking vessel 9 and the left and right side surfaces 23 of the horizontal surface are orthogonal to each other, and the front and rear side surfaces 24 and the left and right side surfaces 23 The bottom surface 25 is orthogonal. The X coil 20 becomes an X axis coil, the Y coil 21 becomes a Y axis coil, and the Z coil 22 becomes a Z axis coil.
Moreover, when each said surface is formed about the electric cooking vessel 9, the X, Y, Z coil 20, 21, 22 is arrange | positioned at each formed surface. On the other hand, when all or a part of each surface is not formed on the electric cooking container 9, a shortage surface is attached to the electric cooking container 9, and X, Y, All or part of the Z coils 20, 21, 22 are disposed.

<< Function of Power Receiving Coil 11 of Third Example (Power Receiving Coil) >>
The power receiving coil 11 of the non-contact power feeding device 6 of the third example (power receiving coil) of FIG. 4 exhibits the following functions by adopting such X, Y, Z coils 20, 21, and 22.
Regardless of the position and direction in which the electric cooking container 9 is placed on the power supply table 12, that is, regardless of the position and direction in which the power receiving coil 11 is placed on the unit coil 18 of the power transmission coil 8, the coupling coefficient is changed. A decline is avoided. The difficulty of electromagnetic coupling and the generation of a feeding null point at which the coupling coefficient becomes zero are avoided.
That is, at least one of the X, Y, and Z coils 20, 21, and 22 of the power receiving coil 11 is electromagnetically coupled to the unit coil 18 of the power transmitting coil 8 regardless of the position and direction. Become.
In particular, even when the Z coil 22 is located across the boundary d between the adjacent unit coils 18 of the power transmission coil 8 and electromagnetic coupling becomes difficult for the Z coil 22 (see FIG. 3 (2)), Electromagnetic coupling can be established for the X and Y coils 20 and 21.

For example, as shown in (5) Figure of Figure 4, the unit coil 18 of the power transmission coil 8, for each coil wire _{19 1,} 19 2, 19 ₃ which is directed in the radial direction, as follows.
First the coil wire _{19 1,} 19 2, 19 ₃ Since both passes through the center of a Z coil 22, no electromagnetic coupling between the Z coil 22.
On the other hand, electromagnetic coupling occurs in one or both of the X coil 20 and the Y coil 21 of the power receiving coil 11. That is, the coil wire 19 _1, only the X coil 20 is electromagnetically coupled, for the coil wire 19 _2, only the Y coil 21 is electromagnetically coupled, for coil wire 19 _3, X coil 20 and the Y coil 21 electromagnetically Join.
FIG. 5 is a circuit diagram of the power receiving circuit 10 in the example of FIG. FIG. 5A shows an example in which the load 14 is an AC resistance, and power is directly supplied from the X, Y, Z coils 20, 21, and 22 to each load 14. FIG. 5B shows an example in which the load 14 is a direct current resistor, and power is supplied from the X, Y, Z coils 20, 21, and 22 via a diode rectifier converter 15.
The third example (power receiving coil) is as described above.

《Action etc.》
The non-contact power feeding device 6 for cooking according to the present invention is configured as described above. Then, it becomes as follows.
(1) During power feeding, one or a plurality of electric cooking containers 9 are placed on the power feeding table 12 (see FIG. 1 (4)).

  (2) Therefore, the small receiving coil 11 of the receiving circuit 10 on the electric cooking vessel 9 side corresponds to the larger transmitting coil 8 of the transmitting circuit 7 on the feeding table 12 in the vertical relationship. And is placed inside the magnetic field position of the power transmission coil 8 (see each figure in FIG. 1).

(3) In this non-contact power feeding device 6 for cooking, the power transmission coil 8 and the power reception coil 11 are electromagnetically coupled in this way, and high frequency power is supplied from the power transmission side circuit 7 to the power reception side circuit 10. .
That is, high-frequency power is transferred from the feeding table 12 side to the electric cooking vessel 9 side by a magnetic resonance coupling method based on the mutual induction action of electromagnetic induction while maintaining a non-contact gap distance electrically and non-contactingly. (Refer to FIGS. 1 and 2).

(4) Now, according to this non-contact electric power feeder 6 for cooking, it becomes like the following 1st, 2nd, 3rd, 4th.
First, the non-contact power feeding device 6 employs different diameter coils for the power transmission coil 8 and the power reception coil 11. Regardless of the type and size of the power receiving coil 11, power can be supplied anywhere on the power transmitting coil 8 having a larger diameter (see FIG. 1).
That is, the electric cooking container 9 can be powered regardless of its type and size, regardless of where it is placed on the feeding table 12.

  Secondly, the non-contact power feeding device 6 has a configuration based on coils of different diameters, and can be used for various power receiving coils 11 and electric cooking containers 9 with a single power transmission coil 8 and power feeding table 12. is there. Thus, it is easy and convenient to use, does not get in the way, and the configuration is simplified.

Thirdly, in the non-contact power feeding device 6, as in the above-described second example (power transmission coil) (see FIG. 3), the power transmission coil 8 is a multipolar structure composed of an even number of unit coils 18. In addition, since the directions of the current and the magnetic field between the adjacent unit coils 18 are opposite to each other, the following (A) and (B) are obtained.
(A) Since the power transmission coil 8 is multipolarized in each unit coil 18, the generated magnetic force is set wider in a wider area, and the power receiving coil 4 is positioned closer to the coil wire 19. Become. As a result, a high coupling coefficient can be obtained on the whole and on average, and the power supply efficiency becomes excellent. As described above, the power transmission coil 8 exhibits a function of suppressing occurrence of a decrease in power supply efficiency.
(B) Each unit coil 18 of the power transmission coil 8 has the opposite direction of the formed electromagnetic field. Thus, the electromagnetic field radiated to the vicinity is weakened by overlapping and canceling each other.
Thus, electromagnetic waves that are diffused outside are greatly reduced. In this way, the power transmission coil 8 exhibits a function of reducing the external diffusion of the magnetic field and a function of containing the magnetic field.

Fourthly, in the non-contact power feeding device 6, in addition to the above-described multipolar structure of the power transmission coil 8, the power reception coil 11 is further changed to X as in the above-described third example (power reception coil) (see FIG. 4). , Y, Z coils 20, 21, 22 are configured as a combination of three-dimensional three-way coils.
Regardless of the position and direction in which the electric cooking vessel 9 and the power receiving coil 11 are placed, one or more of the X, Y, Z coils 20, 21, 22 are electromagnetically coupled to the unit coil 18 of the power transmitting coil 8. It becomes like this.
Regarding the power transmission coil 8 having a multipolar structure, at least one of the X, Y, Z coils 20, 21, and 22 of the power reception coil 11 is present even when the induced magnetic field is positioned between adjacent unit coils 18 having opposite directions. The unit coil 18 of the power transmission coil 8 is electromagnetically coupled.
Thus, a situation in which the coupling coefficient between the power transmission coil 8 and the power reception coil 11 is reduced during power feeding is avoided. In particular, the occurrence of a feeding null point, where the coupling coefficient becomes zero and feeding is impossible, is avoided.
As for the action, it is as above.

A Table a Center b Peripheral c Inner d Boundary φ Magnetic flux 1 Feeding stand (conventional example)
2 Power transmission coil (conventional example)
3 Electric cooking container (conventional example)
4 Power receiving coil (conventional example)
5 Non-contact power feeding device (conventional example)
6 Non-contact power feeding device (present invention)
7 power transmission side circuit 8 power transmission coil (present invention)
9 Electric cooking container (present invention)
10 power receiving side circuit 11 power receiving coil (present invention)
12 Power supply table (present invention)
13 High Frequency Power Supply 14 Load 15 Converter 16 Parallel Capacitor 17 Parallel Capacitor 18 Unit Coil 19 Coil Wire 19 ₁ Coil Wire 19 ₂ Coil Wire 19 ₃ Coil Wire 20 X Coil 21 Y Coil 22 Z Coil 23 Left and Right Sides 24 Front and Back Sides 25 Bottom 26 surface

Claims (1)

Based on the mutual induction effect of electromagnetic induction, power is transmitted in a non-contact manner from the power transmission coil of the power transmission circuit arranged on the power supply table side of the kitchen or table to the power reception coil of the power reception circuit arranged on the electric cooking container side. A non-contact power feeding device for cooking,
The power transmission coil is wound in a large loop shape, and the power receiving coil is wound in a loop shape smaller in diameter than the power transmission coil,
The power receiving coil is positioned in a vertical relationship with the power transmission coil during power feeding, and is placed within the magnetic field position of the power transmission coil.
The power transmission coil is composed of a planar assembly of an even number of unit coils, and has a multipolar structure, and each unit coil is arranged in a line and adjacently arranged between a current direction and a magnetic field. It has a setting in which the direction of
Accordingly, the power transmission coil is formed with a wide magnetic field for each unit coil, and the power receiving coil is located near the coil wire having a strong magnetic force of each unit coil. While exhibiting the suppression function,
The power transmission coil has a large diameter, and due to a large dimensional difference from the small diameter power receiving coil, a large amount of magnetic field is likely to be externally diffused. Based on the setting, the function of reducing the external diffusion of the magnetic field is demonstrated by canceling the overlapping part between adjacent magnetic fields,
Furthermore, when the power receiving coil is positioned across the unit coils arranged adjacent to each other with the direction of the magnetic field of the power transmitting coil reversed, there is a possibility that electromagnetic coupling may become difficult,
The power receiving coil is composed of a three-dimensional assembly of three-way coils of an X coil, a Y coil, and a Z coil. The X coil is disposed on the left and right side surfaces of the electric cooking vessel, and the Y coil is the electric coil. Disposed on the front and rear sides of the cooking container, and the Z coil is disposed on the bottom of the electric cooking container,
Therefore, even in the above-described case, at least one of the X coil, the Y coil, and the Z coil exhibits an electromagnetic coupling function with the unit coil of the power transmission coil.

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