JP7059759B2 - Coil unit, wireless power transmission device, wireless power receiving device and wireless power transmission system - Google Patents

Description

The present invention relates to a coil unit, a wireless power transmission device, a wireless power receiving device and a wireless power transmission system.

Wireless power transfer technology is known. Wireless power transfer technology utilizes the electromagnetic induction action between a primary (transmission) coil and a secondary (power receiving) coil to transmit power wirelessly.
Patent Document 1 discloses a coil unit for wireless power transmission including a coil body and an insulating member.

JP-A-2015-12066

By the way, since the coil generates heat when a current flows through the conductor of the coil, temperature control of the coil is important in wireless power transmission technology. Therefore, the coil unit is required to be able to measure the internal temperature.
However, in the coil unit for wireless power transmission described in Patent Document 1, there is room for study on state management such as coil temperature.

The present invention provides a coil unit capable of easily performing coil state management, and a wireless power transmission device, a wireless power receiving device, and a wireless power transmission system including the coil unit.

The coil unit of the present invention includes a coil having a winding portion in which a conducting wire is wound in a spiral shape, and a base material having an accommodating portion for accommodating the winding portion inside. The accommodating portion is formed along a first wall surface member having a first wall surface formed along a conducting wire on the outermost peripheral side of the winding portion and a conducting wire on the innermost peripheral side of the winding portion. It has a second wall surface member having a second wall surface. The first wall surface member is formed with a first outlet from which the conductor on the outermost peripheral side of the winding portion is drawn from the inside to the outside of the accommodating portion, and the second wall surface member is formed with the winding. A second outlet is formed in which the conductor on the innermost peripheral side of the wire portion is drawn out from the inside to the outside of the accommodating portion. An opening penetrating from the inside to the outside of the accommodating portion is formed in one or both of the first wall surface and the second wall surface.

According to the present invention, it is possible to provide a coil unit capable of easily performing coil state management, a wireless power transmission device including the coil unit, a wireless power receiving device, and a wireless power transmission system.

It is a block diagram which shows an example of the wireless power transmission system which concerns on one Embodiment. It is a circuit diagram which shows the structure of the power transmission coil unit and the power receiving coil unit of the wireless power transmission system of FIG. It is a top view of the coil unit which concerns on one Embodiment. It is a top view of the coil unit which concerns on other embodiment. It is a top view of the coil unit which concerns on other embodiment. It is a top view of the coil unit which concerns on other embodiment.

Hereinafter, the present embodiment will be described in detail with reference to the drawings as appropriate. In the drawings used in the following description, the feature portion may be enlarged for convenience. The dimensional ratio of each component may differ from the actual one. The materials, dimensions, etc. exemplified in the following description are examples. The present invention is not limited to these examples, and can be appropriately modified and implemented without changing the gist.

<Wireless power transmission system>
First, as an embodiment of the present invention, for example, the wireless power transmission system 100 shown in FIGS. 1 and 2 will be described. FIG. 1 is a configuration diagram showing an example of a wireless power transmission system 100. FIG. 2 is a circuit diagram showing the configurations of the power transmission coil unit 203 and the power reception coil unit 301 of the wireless power transmission system 100.

As shown in FIGS. 1 and 2, the wireless power transmission system 100 of the present embodiment wirelessly charges a battery (secondary battery) mounted on an electric vehicle EV. An electric vehicle EV is an electric vehicle (moving body) that travels by driving a motor with electric power charged in a battery. In the present embodiment, the wireless power transmission system 100 is applied to the electric vehicle EV, but in other embodiments, the wireless power transmission system may be applied to a mobile body, a mobile device, or the like other than the electric vehicle EV.

The wireless power transmission system 100 includes a wireless power transmission device 200 and a wireless power receiving device 300. The wireless power transmission device 200 is installed on the ground G on the charging equipment side. The wireless power receiving device 300 is mounted on the electric vehicle EV.

The wireless power transmission device 200 includes a conversion circuit 201, a power transmission circuit 202, and a power transmission coil unit 203. The wireless power receiving device 300 includes a power receiving coil unit 301 and a rectifying smoothing circuit 303. The load Vload is arranged outside the wireless power receiving device 300.

The conversion circuit 201 is electrically connected to an external commercial power supply P and functions as an AC / DC power supply that converts an AC voltage input from the commercial power supply P into a desired DC voltage. The conversion circuit 201 is electrically connected to the power transmission circuit 202. The conversion circuit 201 supplies the converted DC voltage to the power transmission circuit 202.

The conversion circuit 201 may be any as long as it outputs a DC voltage to the power transmission circuit 202, and its configuration is not particularly limited. The conversion circuit 201 is a conversion circuit that combines a rectifier circuit that rectifies an AC voltage and converts it into a DC voltage and a PFC (Power Factor Correction) circuit that improves the power factor; the rectifier circuit and a switching circuit such as a switching converter. A conversion circuit or the like in which the above is combined is exemplified.

The power transmission circuit 202 converts the DC voltage supplied from the conversion circuit 201 into an AC voltage. Examples of the power transmission circuit 202 include a switching circuit in which a plurality of switching elements are bridge-connected. The power transmission circuit 202 is electrically connected to the power transmission coil unit 203. The power transmission circuit 202 supplies the power transmission coil unit 203 with an AC voltage whose drive frequency is controlled based on the resonance frequency of the first LC resonance circuit described later included in the power transmission coil unit 203.

The power transmission coil unit 203 includes a first LC resonance circuit and a base material (not shown). The base material (not shown) will be described in detail in the section “<Coil unit>” described later. The first LC resonant circuit includes a power transmission coil L1 and a power transmission side capacitor C1. By bringing the resonance frequency of the first LC resonance circuit closer to (including the case of matching) the resonance frequency on the power receiving coil unit 301 side, wireless power transmission of the magnetic field resonance method is possible. The power transmission coil unit 203 may further include a magnetic material. Further, in another embodiment, the power transmission coil unit may not be provided with an LC resonance circuit. That is, in another embodiment, the power transmission coil unit may not include a power transmission side capacitor.

In the power transmission coil unit 203 of the present embodiment, the reactor Ls is inserted in series with the power transmission side capacitor C1. In this configuration, it becomes easy to control so that the imaginary part of the impedance of the wireless power transmission network including the power transmission coil unit 203, the power reception coil unit 301, the rectifying smoothing circuit 303, and the load Vload becomes positive. The reactor Ls has a high impedance with respect to a frequency component sufficiently higher than the resonance frequency on the transmission coil unit 203 side. This can function as a filter for removing high frequency components.

The power transmission coil L1 is composed of a wireless power transmission coil. The power transmission coil L1 of the present embodiment is installed on the ground G or embedded in the ground G so as to face the bottom of the floor of the electric vehicle EV. In this embodiment, the power transmission coil L1 (power transmission coil unit 203) is installed on the ground G together with the conversion circuit 201.

The power transmission side capacitor C1 has a function of adjusting the resonance frequency. The power transmission side capacitor C1 of the present embodiment is composed of a first capacitor C11 connected in series with the power transmission coil L1 and a second capacitor C12 connected in parallel with the power transmission coil L1. However, it is not limited to such a configuration. For example, the configuration may be composed of only the first capacitor C11 connected in series with the power transmission coil L1.

The power receiving coil unit 301 includes a second LC resonance circuit and a base material (not shown). The base material (not shown) will be described in detail in the section “<Coil unit>” described later.
The second LC resonant circuit includes a power receiving coil L2 and a power receiving side capacitor C2. By bringing the resonance frequency of the second LC resonance circuit closer to (including the case of matching) the resonance frequency on the transmission coil unit 203 side, wireless power transmission of the magnetic field resonance method is possible. The power receiving coil unit 301 may further include a magnetic material. Further, in another embodiment, the power receiving coil unit may not be provided with an LC resonance circuit. That is, in another embodiment, the power receiving coil unit may not include the power receiving side capacitor.

The power receiving coil unit 301 of the present embodiment has a configuration in which the reactor Lr is inserted in series with the power receiving side capacitor C2. In the case of this configuration, the reactor Lr has a high impedance with respect to a frequency component sufficiently higher than the resonance frequency on the power receiving coil unit 301 side. This can function as a filter for removing high frequency components.

The power receiving coil L2 is composed of a wireless power transmission coil. The power receiving coil L2 of the present embodiment is installed under the floor of the electric vehicle EV so as to face the power transmission coil L1 installed on the above-mentioned ground G or embedded in the ground G.

The power receiving side capacitor C2 has a function of adjusting the resonance frequency. The power receiving side capacitor C2 of the present embodiment is composed of a third capacitor C21 connected in series with the power receiving coil L2 and a fourth capacitor C22 connected in parallel with the power receiving coil L2. However, it is not limited to such a configuration. For example, it may be configured to include only the third capacitor C21 connected in series with the power receiving coil L2.

The rectifying smoothing circuit 303 is electrically connected to the power receiving coil unit 301, rectifies the AC voltage supplied from the power receiving coil L2, and converts it into a DC voltage. The rectifying and smoothing circuit 303 is a half-wave rectifying and smoothing circuit composed of one switching element or diode and a smoothing capacitor; and a full-wave rectifying and smoothing circuit composed of four bridge-connected switching elements or diodes and a smoothing capacitor. Etc. are exemplified. The rectifying smoothing circuit 303 is electrically connected to the load Vload. The rectifying smoothing circuit 303 supplies the converted DC power to the load Vload. The wireless power receiving device 300 may be configured to include a charging circuit between the rectifying smoothing circuit 303 and the load Vload.

The load Vload is connected between the output terminals of the rectifying smoothing circuit 303, and a DC voltage is supplied from the rectifying smoothing circuit 303. Examples of the load Vload include a battery, a motor, and the like mounted on the above-mentioned electric vehicle EV.

The load Vload can be regarded as a resistance load in which the equivalent resistance value changes with time depending on the demand state (storage state or consumption state) of electric power. The power consumption of the rectifying smoothing circuit 303 is sufficiently smaller than the power consumption of the load Vload.

In the power transmission system 100 having the configuration described above, the wireless power transmission device 200 is directed toward the wireless power reception device 300 by a magnetic field resonance method using a resonance phenomenon between the power transmission coil unit 203 and the power reception coil unit 301. , Power can be transmitted wirelessly. That is, in this magnetic field resonance method, the resonance frequency of the first LC resonance circuit and the resonance frequency of the second LC resonance circuit are brought close to each other (including the case where they are matched), and the high-frequency current and voltage in the vicinity of this resonance frequency are set. It is possible to wirelessly transmit (supply) power to the power receiving coil unit 301 which is applied to the power transmission coil unit 203 and electromagnetically resonates (resonates). The wireless power transmission device 200 and the wireless power receiving device 300 may include a communication circuit for communicating between the wireless power transmission device 200 and the wireless power receiving device 300.

Therefore, in the power transmission system 100 of the present embodiment, the battery mounted on the electric vehicle EV is wirelessly transmitted to the electric vehicle EV without connecting to the charging cable. It is possible to charge the battery wirelessly.

<Coil unit>
Next, as the coil unit of one embodiment, the coil unit 1 shown in FIG. 3 will be described. FIG. 3 is a plan view of the coil unit 1.
As shown in FIG. 3, the coil unit 1 includes a coil 10 and a base material 20. The coil 10 can be used as both the power transmission coil L1 and the power reception coil L2.
In the coil unit 1, the coil 10 and the base material 20 are housed in a housing (not shown). The coil unit 1 may further include either one or both of a capacitor and a magnetic material. When the coil unit 1 further includes one or both of a capacitor and a magnetic material, the capacitor and the magnetic material are not particularly limited.

The coil 10 has a winding portion 11, a first wiring portion 12, and a second wiring portion 13.
The winding portion 11 is a portion where the conducting wire 14 is wound in a spiral shape. The conductor 14 is not particularly limited. The conductor 14 may be a litz wire containing, for example, copper, aluminum, or the like.
The first wiring portion 12 is a portion in which the conducting wire 14 extends from the winding portion 11 on the outermost peripheral side of the winding portion 11. The second wiring portion 13 is a portion in which the conducting wire 14 extends from the winding portion 11 on the innermost peripheral side of the winding portion 11.

The base material 20 has an accommodating portion 21, a main surface 22, and a hollow portion 23. The accommodating portion 21 is provided on the main surface 22. The planar area on the main surface 22 is divided into a planar area inside the accommodating portion 21 and a planar area outside the accommodating portion 21 by the accommodating portion 21. The hollow portion 23 is a hollow space region formed in the central portion of the main surface 22. In another embodiment, the base material does not have to have a hollow portion.

The accommodating portion 21 has a first wall surface member 51 and a second wall surface member 52. The first wall surface member 51 has a first wall surface 24. The second wall surface member 52 has a second wall surface 25.
The first wall surface 24 is a wall surface formed along the lead wire 14 on the outermost peripheral side of the winding portion 11. Therefore, the first wall surface 24 functions as an outer peripheral wall of the accommodating portion 21. Specifically, the first wall surface 24 is provided on the main surface 22. The position of the outermost conductor 14 of the winding portion 11 is fixed by the first wall surface 24. Then, the inner flat area of the accommodating portion 21 and the outer planar area of the accommodating portion 21 are separated by the first wall surface 24 on the outermost peripheral side of the winding portion 11.
The second wall surface 25 is a wall surface formed along the conductor 14 on the innermost peripheral side of the winding portion 11. Therefore, the second wall surface 25 functions as an inner peripheral wall of the accommodating portion 21. Specifically, the second wall surface 25 is provided on the main surface 22. The position of the conductor 14 on the innermost circumference of the winding portion 11 is fixed by the second wall surface 25. Then, the plane region inside the accommodating portion 21 and the spatial region outside the accommodating portion 21 are separated by the second wall surface 25 on the innermost peripheral side of the winding portion 11.

The accommodating portion 21 accommodates the winding portion 11 inside the accommodating portion 21. In the coil unit 1, the winding portion 11 is arranged on the main surface 22 of the plane region inside the accommodating portion 21. The lead wire 14 of the winding portion 11 is in contact with the main surface 22 of the plane region inside the accommodating portion 21.
The first outlet 26 is formed on the first wall surface member 51. At the first outlet 26, the conductor 14 on the outermost peripheral side of the winding portion 11 is pulled out from the inside to the outside of the accommodating portion 21. A second outlet 27 is formed on the second wall surface member 52. At the second outlet 27, the conductor 14 on the innermost peripheral side of the winding portion 11 is pulled out from the inside to the outside of the accommodating portion 21.
The conductors 14 drawn from the first outlet 26 and the second outlet 27, respectively, may be connected to electrical components (not shown). Further, the conductor 14 of the first wiring portion 12 may be fixed to the first outlet 26, and the conductor 14 of the second wiring portion 13 may be fixed to the second outlet 27. good. As a result, the position of the lead wire 14 of the coil 10 is less likely to shift.

The first wall surface member 51 includes four curved wall surface members 51a, 51d, 51f, 51h, four linear wall surface members 51b, 51c, 51e, 51g, and a square wall surface 51i. A first outlet 26 is formed on the square wall surface 51i.
The first end of the curved wall member 51a is coupled to the second end of the square wall member 51i, and the second end of the curved wall member 51a is the first end of the linear wall member 51b. Combined with the end. The second end portion of the linear wall surface member 51b is provided at the end portion of the base material 20.
The linear wall surface member 51c is a wall surface parallel to the linear wall surface member 51b and has a portion facing the linear wall surface member 51b. The first end portion of the linear wall surface member 51c is provided at the end portion of the base material 20 so as to face the second end portion of the linear wall surface member 51b.

The first end of the curved wall member 51d is coupled to the second end of the linear wall member 51c, and the second end of the curved wall member 51d is the first end of the linear wall member 51e. Combined with the end. The linear wall surface member 51e is a wall surface perpendicular to the linear wall surface member 51b and the linear wall surface member 51c.
The first end of the curved wall member 51f is coupled to the second end of the linear wall member 51e, and the second end of the curved wall member 51f is the first end of the linear wall member 51g. Combined with the end. The linear wall surface member 51g is a plane parallel to the linear wall surface member 51b and the linear wall surface member 51c.
The first end of the curved wall member 51h is coupled to the second end of the linear wall member 51g, and the second end of the curved wall member 51h is the first end of the square wall member 51i. Combined with the end.

In the coil unit 1, an opening 28 is formed on the first wall surface 24 so as to penetrate from the inside to the outside of the accommodating portion 21. As a result, a temperature measuring device such as a thermocouple can be inserted from the outside to the inside of the accommodating portion 21 through the opening 28.
Specifically, the opening 28 is formed at the joint portion between the linear wall surface member 51b and the curved wall surface member 51a. Further, the opening 28 is opened along the conducting wire 14 of the winding portion 11 of the portion bent by the curved wall surface member 51a.

In the coil unit 1, the first wall surface member 51 further has a first partition wall surface 37, and the second wall surface member 52 further has a second partition wall surface 38. The first partition wall surface 37 is a spiral wall surface formed along the outer peripheral side of the conductor 14 of the winding portion 11, and the first wall surface 24 is directed from the outermost peripheral side to the inner peripheral side along the conductor 14. It is an extended part. The second partition wall surface 38 is a spiral wall surface formed along the inner peripheral side of the conductor 14 of the winding portion 11, and the second wall surface 25 is formed along the conductor 14 from the innermost peripheral side to the outer peripheral side. It is a part that extends toward. As a result, the first partition wall surface 37 is integrally formed with the first wall surface 24, and the second partition wall surface 38 is integrally formed with the second wall surface 25.

As shown in FIG. 3, the first partition wall surface 37 and the second partition wall surface 38 are provided in a plane region inside the accommodating portion 21 along the lead wire 14 of the winding portion 11. As a result, a second groove (not shown), which is a groove-shaped space region, is formed between the first section wall surface 37 and the second section wall surface 38.
In the second groove, the conducting wire 14 of the winding portion 11 is housed one by one. Further, the conductor 14 on the outermost peripheral side of the winding portion 11 is accommodated between the first wall surface 24 and the second partition wall surface 38, and the conductor 14 on the innermost peripheral side of the winding portion 11 is the second. It is housed between the wall surface 25 and the first section wall surface 37. As described above, the first partition wall surface 37 and the second partition wall surface 38 also function as members for accommodating the conductor 14 of the winding portion 11. As a result, the fluctuation of the position of the conducting wire 14 can be suppressed for each turn, and the work of adjusting the length of the conducting wire 14 in the first wiring portion 12 and the second wiring portion 13 becomes easy. In addition, changes in the characteristics of the coil as a power transmission coil can be suppressed. In another embodiment, a plurality of conductors of the winding portion may be accommodated in the second groove.

In the coil unit 1, the first partition wall surface 37 is continuous with the first wall surface 24, which is the outer peripheral wall of the accommodating portion 21, along the lead wire 14 of the winding portion, and the second partition wall surface 38 is the accommodating portion 21. It is continuous along the second wall surface 25, which is the inner peripheral wall, and the conducting wire 14 of the winding portion. That is, the first partition wall surface 37 may be integrally configured with the first wall surface 24, and the second partition wall surface 38 may be integrally configured with the second wall surface 25.

In the coil unit 1, the accommodating portion 21 further has a first groove 30 and a second groove (not shown).
The first groove 30 is formed in a plane region inside the accommodating portion 21 in a direction parallel to the linear wall surface member 51c. In the coil unit 1, the first groove 30 is formed by separating the main surface 22 inside the accommodating portion 21 by the linear wall surface member 51b and the linear wall surface member 51c. The first groove 30 is formed inside the accommodating portion 21 from the end portion of the base material 20 to the opening 28. As a result, a temperature measuring device such as a thermocouple can be linearly inserted from the end portion of the base material 20 into the inside of the accommodating portion 21, and it becomes easier to carry out state management such as temperature measurement of the winding portion 11.

The height of the first section wall surface 37 and the second section wall surface 38 (that is, the depth of the second groove) is not particularly limited. However, the height of the first section wall surface 37 and the second section wall surface 38 is preferably larger than the diameter of the conductor 14 and 1.2 times or less the diameter of the conductor 14. When the height of the first section wall surface 37 and the second section wall surface 38 is larger than the diameter of the conducting wire 14, the coil 10 and other members come into contact with each other when an external force such as vibration or impact is applied to the coil unit 1. It will be easier to prevent. Further, when the height of the first section wall surface 37 and the second section wall surface 38 is 1.2 times or less the diameter of the conducting wire 14, the coil unit 1 can be further thinned. Therefore, if the height of the first partition wall surface 37 and the second partition wall surface 38 is larger than the diameter of the conductor 14 and 1.2 times or less the diameter of the conductor 14, the coil unit 1 is made thinner and the coil 10 is used. And prevention of contact with other members can be achieved at the same time.
When the influence of external force such as vibration and impact on the coil unit 1 is small, it is preferable that the height of the first section wall surface 37 and the second section wall surface 38 is equal to or less than the diameter of the conducting wire 14. As a result, the coil unit 1 can be further made thinner.
In the coil unit 1, it is preferable that the width W of the first groove 30 is longer than the width of the second groove. As a result, sufficient space for work can be secured, and workability is further improved.

The base material 20 further has a surface (not shown). The surface (not shown) is parallel to the main surface 22 and faces the main surface 22. The distance between the surface (not shown) and the main surface 22 is preferably constant. In this case, the distance can be the thickness of the base material 20. The thickness of the base material 20 is not particularly limited, but may be, for example, 0.5 to 5.0 mm.

The base material 20 is made of an insulating member. The insulating member is not particularly limited, and examples thereof include glass and resin. However, resin is preferable as the insulating member. Specific examples of the resin include acrylonitrile-butadiene-styrene copolymer resin (ABS resin), polybutylene terephthalate resin (PBT resin), polyphenylene sulfide resin (PPS resin) and the like.
In the coil unit 1, the base material 20 is in the form of a bobbin. The bobbin is a component for neatly winding the conductor 14 of the coil 10 and maintaining the shape of the conductor 14 of the coil 10.

In the present embodiment, as an example, in the coil unit 1, a form in which a second groove is formed by being separated by a first partition wall surface 37 and a second partition wall surface 38 is shown, but in other embodiments, the second groove is formed. The second groove may be formed so as to engrave a planar area inside the accommodating portion 21. That is, a second groove for arranging the conducting wire 14 of the winding portion 11 may be formed by engraving the base material 20 on the plane region inside the accommodating portion 21.

In the present embodiment, as an example, in the coil unit 1, the conductor 14 of the first wiring portion 12 is extended toward the outer peripheral side region of the base material 20, and the conductor 14 of the second wiring portion 13 is formed in the hollow portion 23. Although the form is shown to be extended toward the direction, the direction in which the conductor 14 of the first wiring portion 12 and the second wiring portion 13 is extended is not particularly limited.

In the present embodiment, in the coil unit 1, as an example, the base material 20 has a first section wall surface 37 and a second section wall surface 38, but the first section wall surface 37 and the second section wall surface 38 are It may be omitted. This form will be described later in Coil Units 2 to 4.

(Action effect)
In the coil unit 1 described above, since the opening 28 penetrating from the inside to the outside of the accommodating portion 21 is formed on the first wall surface 24, a temperature measuring device such as a thermocouple is accommodated through the opening 28. 21 can be inserted from the outside to the inside. Therefore, for example, the temperature of the coil can be easily measured, and the state management of the coil in the coil unit can be easily performed.

By the way, the coil unit for wireless power transmission described in Patent Document 1 may have the following problems in addition to the above-mentioned problem of temperature control of the coil.
In wireless power transmission technology, coil units are required to be thinner and smaller. Therefore, the terminal connection portion between the coil 10 and the electric component other than the coil 10 is also required to be thinner and smaller. The terminal connection portion of the coil unit 1 includes a first wiring portion 12, a second wiring portion 13, and the like.

On the other hand, in the manufacture of the coil unit, when the lead wire is wound and the coil is manufactured, the length of the lead wire 14 of the first wiring portion 12 and the second wiring portion 13 is difficult to be a constant length, and the first The length of the conducting wire 14 of the wiring portion 12 and the second wiring portion 13 was long and sometimes exceeded each outlet. Usually, in these mainly two cases, the lengths of the conductors 14 of the first wiring portion 12 and the second wiring portion 13 are adjusted, and the dimensional accuracy is guaranteed.
However, as described above, in the coil unit, the terminal connection portion is required to be thinner and smaller. Therefore, in addition to the terminal connection work, the work of adjusting the length of the conducting wire may be difficult.

According to the coil unit 1, an opening 28 penetrating from the inside to the outside of the accommodating portion 21 is formed on the first wall surface 24 in order to solve the problems in the terminal connection work and the length adjustment work of the conductor. By directly operating the conductor 14 of the winding portion 11 through the opening 28, the work of adjusting the length of the conductor of each wiring portion becomes easy.

Further, after adjusting the length of the wiring portion to be short through the opening 28, it is possible to perform the terminal connection work between the conducting wire of the wiring portion and the electric component. As described above, even when the coil unit 1 is required to be thinner and smaller, the coil length adjustment work and the terminal connection work are facilitated, and the productivity is improved. Therefore, according to the coil unit 1, not only the temperature can be controlled, but also the coil unit can be made thinner and smaller and the productivity can be improved at the same time.

Further, in the coil unit 1, the opening 28 is formed in the first wall surface 24 of the joint portion between the linear wall surface member 51b and the curved wall surface member 51a, and is bent by the curved wall surface member 51a. It is open along the lead wire 14 of the winding portion 11. Therefore, it is possible to linearly pull out the conductor 14 to the outside of the coil unit 1 without bending the conductor 14 of the winding portion 11 as much as possible, and it is difficult to apply an extra load to the coil 10 even during the length adjustment work. Become.
Further, in the coil unit 1, since the first groove 30 is formed inside the accommodating portion 21, workability is further improved.

FIG. 4 is a plan view of the coil unit 2 according to another embodiment. FIG. 5 is a plan view of the coil unit 3 according to another embodiment. FIG. 6 is a plan view of the coil unit 4 according to another embodiment. In the coil units 2 to 4 shown in FIGS. 4 to 6, the first section wall surface 37 and the second section wall surface 38 described for the coil unit 1 are omitted.
In the following description, the same reference numerals are given to the configurations having the same or similar functions in the configurations of the coil units 2 to 4 and the configurations of the coil unit 1. The description of the overlapping configuration of the coil units 2 to 4 and the coil unit 1 will be omitted.

In the coil unit 2, the accommodating portion 21 has a first wall surface member 51 and a second wall surface member 33. Further, similarly to the coil unit 1, an opening 28 is formed in the first wall surface 24. The second wall surface member 33 has a second wall surface 25 formed along a conducting wire 14 on the innermost peripheral side of the winding portion 11.
In the coil unit 3, the accommodating portion 21 has a first wall surface member 32 and a second wall surface member 33. The first wall surface member 32 has a first wall surface 24. Specifically, the first wall surface member 32 includes four linear wall surface members and four curved wall surface members. By alternately connecting these linear wall surface members and curved wall surface members, the outer peripheral wall of the accommodating portion 21 is formed. Further, an opening 29 is formed in the second wall surface 25. The opening 29 is an opening that penetrates from the inside to the outside of the accommodating portion 21. The position where the opening 29 is formed on the second wall surface 25 is not particularly limited.
In the coil unit 4, the accommodating portion 21 has a first wall surface member 51 and a second wall surface member 33. Further, an opening 28 is formed in the first wall surface 24, and an opening 29 is formed in the second wall surface 25.

In the coil units 2 to 4 described above, since an opening penetrating from the inside to the outside of the accommodating portion 21 is formed on either one or both of the first wall surface and the second wall surface, the coil unit The same action and effect as in 1 can be obtained. Therefore, even in the coil units 2 to 4, the state management of the coil can be easily carried out, and the coil unit can be made thinner and smaller and the productivity can be improved at the same time.

1 to 4 ... coil unit, 10 ... coil, 11 ... winding part, 12 ... first wiring part, 13 ... second wiring part, 14 ... lead wire, 20 ... base material, 21 ... accommodating part, 22 ... main Surface, 23 ... Hollow portion, 24 ... First wall surface, 25 ... Second wall surface, 26 ... First outlet, 27 ... Second outlet, 28, 29 ... Opening, 30 ... First groove, 31 ... partition wall surface, 37 ... first section wall surface, 38 ... second section wall surface, 32, 51 ... first wall surface member, 33, 52 ... second wall surface member, 100 ... wireless power transmission system, 200 ... Wireless power transmission device, 201 ... conversion circuit, 202 ... power transmission circuit, 203 ... power transmission coil unit, 300 ... wireless power receiving device, 301 ... power receiving coil unit, 303 ... rectifying smoothing circuit, L1 ... power transmission coil, L2 ... power receiving coil, C1 ... Transmission side coil, C2 ... Power receiving side capacitor, EV ... Electric vehicle, Vload ... Load

Claims (7)

A coil with a winding part where the conductor is spirally wound, and
A base material having an accommodating portion for accommodating the winding portion inside,
Equipped with
The accommodating part
A first wall surface member having a first wall surface formed along a conducting wire on the outermost peripheral side of the winding portion, and a first wall surface member.
A second wall surface member having a second wall surface formed along a conducting wire on the innermost peripheral side of the winding portion, and a second wall surface member.
Have,
The first wall surface member is formed with a first outlet from which a conducting wire on the outermost peripheral side of the winding portion is drawn from the inside to the outside of the accommodating portion.
The second wall surface member is formed with a second outlet from which the conductor on the innermost peripheral side of the winding portion is drawn from the inside to the outside of the accommodating portion.
An opening penetrating from the inside to the outside of the accommodating portion is formed in one or both of the first wall surface and the second wall surface .
The first wall surface comprises a linear wall surface and a curved wall surface coupled to the end of the linear wall surface.
A coil unit in which the opening is formed in a joint portion between the linear wall surface and the curved wall surface . The accommodating portion further has a first groove formed in a direction parallel to the linear wall surface.
The coil unit according to claim 1 , wherein the first groove is formed inside the accommodating portion from the end portion of the base material to the opening portion. The first wall surface member further has a first partition wall surface formed along the outer peripheral side of the conductor of the winding portion.
The second wall surface member further has a second partition wall surface formed along the inner peripheral side of the conductor of the winding portion.
The coil unit according to claim 1 or 2 , wherein the lead wire of the winding portion is housed between the first section wall surface and the second section wall surface. The first wall surface member further has a first partition wall surface formed along the outer peripheral side of the conductor of the winding portion.
The second wall surface member further has a second partition wall surface formed along the inner peripheral side of the conductor of the winding portion.
The accommodating portion further comprises a second groove formed by the first compartment wall surface and the second compartment wall surface.
The coil unit according to claim 2 , wherein the length of the width of the first groove is longer than the length of the width of the second groove. It is a wireless power transmission device that transmits electric power wirelessly.
A wireless power transmission device comprising the coil unit according to any one of claims 1 to 4 . It is a wireless power receiving device that receives power wirelessly.
A wireless power receiving device comprising the coil unit according to any one of claims 1 to 4 . A wireless power transmission system that wirelessly transmits power from a wireless power transmission device to a wireless power receiving device.
A wireless power transmission system comprising the coil unit according to any one of claims 1 to 4 , wherein at least one of the wireless power transmission device and the wireless power receiving device is provided.

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