Non-contact power supply device

Abstract

The present invention includes two coil units (12A, 12B), each having an annular winding (13A, 13B) and at least one magnetic body (14A, 14B) covering a portion of the winding. The two coil units are disposed coaxially so as to face each other. The number of magnetic bodies of one of the two coil units differs from the number of magnetic bodies of the other of the two coil units. In order to maintain a facing area between the magnetic bodies of the two coil units constant when a relative positional relationship between the two coil units in a rotational direction about a common axis changes, the magnetic bodies are disposed at constant intervals in each of the two coil units.

Description

Contactless power supply device

[0001] This disclosure relates to a contactless power supply device.

[0002] A contactless power supply device is a device composed of at least two types of coil units: a coil unit that transmits power without contact and a coil unit that receives power without contact. Each coil unit mainly consists of a winding provided for transmitting or receiving power, and a magnetic material provided to cover the winding to promote coupling between coil units.

[0003] In contactless power supply devices mounted on rotating bodies, for example, at least one coil unit is mounted so as to be rotatable around the coaxial axis of the rotating mechanism. In this case, the magnetic material may be divided and intermittently arranged with gaps between them, rather than covering the entire circumference of the winding, for purposes such as reducing the weight of the rotating body and lowering the cost of the contactless power supply device. However, when divided magnetic material is arranged intermittently, when the relative positional relationship between coil units in the rotational direction around the coaxial axis changes, an imbalance occurs in the opposing surface area of ​​the magnetic material between the coil units. As a result, the coupling between coil units changes. When the coupling between coil units changes, the voltage and current of each part of the contactless power supply circuit change. Therefore, when a contactless power supply device with divided magnetic material arranged intermittently is mounted on a rotating body, there is a problem that the voltage and current supplied to the load become unstable when the relative positional relationship between coil units in the rotational direction around the coaxial axis changes.

[0004] To solve this problem, a non-contact power supply device has been disclosed that suppresses the unevenness of the opposing surface area of ​​magnetic materials by making the number of magnetic materials in each coil unit different from the number of magnetic materials in the magnetic materials facing each other between coil units (see, for example, Patent Document 1).

[0005] Japanese Patent Publication No. 2000-150276

[0006] Conventional contactless power supply devices, which use varying numbers of magnetic materials, can suppress the degree of bias in the opposing surface area of ​​the magnetic materials when the relative positional relationship between coil units in the rotational direction around the coaxial axis changes. However, this is insufficient to keep the opposing surface area of ​​the magnetic materials constant. Furthermore, in conventional contactless power supply devices, increasing the number of magnetic materials tends to further suppress the bias in the opposing surface area of ​​the magnetic materials when the relative positional relationship between coil units in the rotational direction around the coaxial axis changes. However, since the manufacturing process of magnetic materials has a significant impact on costs, increasing the number of magnetic materials tends to lead to higher costs for contactless power supply devices.

[0007] This disclosure was made to solve the above-mentioned problems, and aims to provide a lightweight and low-cost contactless power supply device that suppresses fluctuations in coupling between coil units without unnecessarily increasing the number of magnetic materials, thereby stabilizing circuit operation.

[0008] The contactless power supply device of this disclosure comprises two coil units, each having an annular winding and at least one magnetic material covering a portion of the winding. The coil units are arranged opposite each other around a coaxial axis, and the number of magnetic materials in one coil unit is different from the number of magnetic materials in the other coil unit. The magnetic materials are arranged with a certain gap between them in each coil unit so that the opposing area of ​​the magnetic materials remains constant when the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0009] In the contactless power supply device of this disclosure, the number of magnetic materials in one coil unit is different from the number of magnetic materials in the other coil unit. The magnetic materials are arranged with a certain gap between them so that the opposing area of ​​the magnetic materials remains constant when the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes. Therefore, without increasing the number of magnetic materials unnecessarily, fluctuations in the coupling between the coil units are suppressed, the circuit operation is stabilized, and a lightweight and low-cost contactless power supply device can be provided.

[0010] This is a perspective view of the contactless power supply device according to Embodiment 1. This is a bottom view of the coil unit according to Embodiment 1. This is a top view of the coil unit according to Embodiment 1. This is a characteristic diagram of the contactless power supply device according to Embodiment 1. This is a bottom view of the coil unit according to Embodiment 1. This is a bottom view of the coil unit according to Embodiment 1. This is a bottom view of the coil unit according to Embodiment 1. This is a cross-sectional view of the coil unit according to Embodiment 1. This is a cross-sectional view of the coil unit according to Embodiment 1. This is a cross-sectional view of the coil unit according to Embodiment 1. This is a bottom view of the coil unit according to Embodiment 2. This is a top view of the coil unit according to Embodiment 2. This is a bottom view of the coil unit according to Embodiment 3. This is a top view of the coil unit according to Embodiment 3. This is a top view of the coil unit according to Embodiment 3. This is a bottom view of the coil unit according to Embodiment 4. This is a top view of the coil unit according to Embodiment 4. This is a top view of the coil unit according to Embodiment 4.

[0011] The following will describe in detail, with reference to the drawings, a contactless power supply device according to an embodiment for implementing this disclosure. In each drawing, the same reference numerals indicate the same or corresponding parts.

[0012] Embodiment 1. Figure 1 is a perspective view of a contactless power supply device according to Embodiment 1. Coil unit 12A has an annular winding 13A and a magnetic material 14A that is divided and arranged with a certain gap 15A between them so as to cover the winding 13A. Coil unit 12B has an annular winding 13B and a magnetic material 14B that is divided and arranged with a certain gap 15B between it and the winding 13B so as to cover the winding 13B. In the contactless power supply device 11 of this embodiment, coil units 12A and 12B are arranged opposite each other around a coaxial axis. Coil units 12A and 12B are each integrally molded coil units and are mounted so that at least one of the coil units is rotatable and there is no mechanical contact between them.

[0013] Coil units 12A and 12B are such that one of them is a coil unit that transmits power without contact, and the other is a coil unit that receives power. Furthermore, both coil units 12A and 12B may have either the function of transmitting power or receiving power.

[0014] Figure 2 is a bottom view of the coil unit 12A of the contactless power supply device according to this embodiment, and Figure 3 is a top view of the coil unit 12B of the contactless power supply device according to this embodiment. In Figures 2 and 3, the lines used to divide the coil unit into four equal parts at a 90° angle are shown as dashed lines.

[0015] The following explains the conditions under which the opposing area of ​​the magnetic materials remains constant even when the relative positional relationship between coil units in the rotational direction around the coaxial axis changes. First, the number of magnetic materials 14A and 14B is determined so that the number of each magnetic material in each coil unit is different. The number of magnetic materials 14A in coil unit 12A is n １ n, the number of magnetic materials 14B in the coil unit 12B ２ The coil unit 12A is designed to reduce the number of magnetic materials 14A. １ = 1. The coil unit 12B only needs to be configured such that the number of magnetic materials 14B is different from the number of magnetic materials 14A, and following the same purpose as the number of magnetic materials 14A, n ２ It is set to =2.

[0016] Next, the angle that the magnetic material 14A or 14B occupies with respect to the angle of one turn of the winding (360°) is determined. The magnetic material in at least one coil unit is such that it occupies the angle expressed by equation (1) with respect to the angle of one turn of the winding. Here, n １ to n ２ Let m be the least common multiple of k and k, and let k be any natural number.

[0017] The angle occupied by the magnetic material = 360° / m × k (1)

[0018] The least common multiple of the number of magnetic materials 14A in coil unit 12A and the number of magnetic materials 14B in coil unit 12B is 2. Therefore, the magnetic materials in at least one coil unit are sized to occupy 180° of the angle of one turn of the winding. Here, the magnetic materials 14A in coil unit 12A are arranged to occupy 180° (k=1) of the angle of one turn of the winding.

[0019] Furthermore, the angle that the gap 15A between both ends of the magnetic material 14A occupies with respect to the angle of one turn of the winding must be constant. The gap in the target coil unit must be such that it occupies the angle expressed by equation (2).

[0020] The angle occupied by the gap = 360° / (number of magnetic materials in the target coil unit) - (angle occupied by one magnetic material in the target coil unit relative to the angle of one turn of the winding) (2)

[0021] According to equation (2), the gap 15A occupies a size equivalent to 180° of the angle of one turn of the winding. Each of the magnetic materials 14B of the coil unit 12B can be arbitrarily selected relative to the angle of one turn of the winding, since the angle that the magnetic material 14A of the coil unit 12A occupies relative to the angle of one turn of the winding satisfies the conditions shown in equation (1). Here, each of the magnetic materials 14B is arranged to occupy a size equivalent to 90° of the angle of one turn of the winding. In addition, the angle that the gap 15B at both ends of the magnetic material 14B occupies relative to the angle of one turn of the winding must be kept constant. According to equation (2), the gap 15B occupies a size equivalent to 90° of the angle of one turn of the winding.

[0022] As shown in Figure 1, when coil units 12A and 12B are configured to face each other around the same axis, the area where magnetic materials 14A and 14B face each other occupies 90° of the angle of one turn of the winding. Furthermore, when at least one of coil units 12A and 12B rotates around the same axis, even if the area where one magnetic material 14B faces the magnetic material 14A decreases by a certain amount, the area where the other magnetic material 14B faces the magnetic material 14A increases by a certain amount. As a result, it is possible to keep the area where magnetic materials 14A and 14B face each other constant even if the relative positional relationship between the coil units in the rotational direction around the same axis changes.

[0023] Next, the coupling coefficient characteristics for each rotation angle in the contactless power supply device of this embodiment will be explained using the graph in Figure 4. Figure 4 is a characteristic diagram of the contactless power supply device of this embodiment. In Figure 4, the data 16 shown by the solid line represents the coupling coefficient characteristics for each rotation angle under the magnetic material arrangement conditions shown in Figures 2 and 3. The data 17 shown by the dashed line represents the coupling coefficient characteristics for each rotation angle of the contactless power supply device of the comparative example. Here, the contactless power supply device of the comparative example is one in which the magnetic material 14A in Figure 2 is sized to occupy 90° of the angle of one turn of the winding. In the contactless power supply device of the comparative example, the arrangement of the magnetic material 14B is the same as in Figure 3.

[0024] The data shown by the solid line 16 and the data shown by the dashed line 17 are data acquired at 10° intervals by electromagnetic field analysis when one coil unit is rotated up to 180° in the rotational direction around the coaxial axis, starting from an arbitrary initial rotation angle (0°). In this case, the data shown by the solid line 16 and the data shown by the dashed line 17 are expressed as ratios to the average value, with the average value of the acquired coupling coefficient set to 1p.u.

[0025] The coupling coefficient with respect to the change in rotation angle shows no change in data 16, which is shown by a solid line, while in data 17, which is shown by a dashed line, a fluctuation of approximately ±20% is observed around 1 p.u. This difference in results is because, in the non-contact power supply device of this embodiment, it is possible to keep the opposing area of ​​the magnetic material constant even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes, whereas in the non-contact power supply device of the comparative example, a bias occurs in the opposing area of ​​the magnetic material.

[0026] Thus, in the contactless power supply device of this embodiment, the number of magnetic materials is not increased unnecessarily, and even if the relative positional relationship between coil units in the rotational direction around the coaxial axis fluctuates, the opposing area of ​​the magnetic materials can be kept constant. This suppresses fluctuations in coupling, stabilizes circuit operation, and results in a lightweight and low-cost device.

[0027] In the diagrams described so far, the magnetic material was configured to be ring-shaped and surround the winding. However, each magnetic material only needs to occupy a certain angle with respect to the angle of one full turn of the winding, and be positioned with a certain gap between them with respect to the angle of one full turn of the winding; therefore, the shape of the magnetic material is not limited to rings.

[0028] Figures 5, 6, and 7 are top or bottom views of one coil unit according to this embodiment. Here, the coil units 22, 32, and 42 shown in Figures 5, 6, and 7, respectively, have one magnetic material 24, 34, and 44, and the magnetic materials 24, 34, and 44 are all arranged to occupy an angle of 180° relative to the angle of one turn of the winding. The magnetic material 24 shown in Figure 5 is a fan-shaped magnetic material that occupies an angle of 180° relative to the angle of one turn of the winding. The magnetic material 34 shown in Figure 6 is made by arranging four annular magnetic materials, each occupying an angle of 45° relative to the angle of one turn of the winding, without any gaps, to occupy an angle of 180° relative to the angle of one turn of the winding. The magnetic material 44 shown in Figure 7 is made by arranging a magnetic material with a square cross-section and a magnetic material with a triangular cross-section without any gaps, to occupy an angle of 180° relative to the angle of one turn of the winding. Thus, in the contactless power supply device of this embodiment, the magnetic material of at least one coil unit may be composed of a single or a combination of multiple magnetic materials.

[0029] Figures 8, 9, and 10 are cross-sectional views of a single coil unit. The magnetic material 54 shown in Figure 8 has a concave shape that covers the side and bottom surfaces of the winding 53. The magnetic material 64 shown in Figure 9 has a shape that covers the bottom surface of the winding 63. The magnetic material 74 shown in Figure 10 has a shape that covers both sides of the winding 73. The magnetic material in the coil unit of this embodiment may have shapes other than those of the magnetic materials 24, 34, 44, 54, 64, and 74 shown in Figures 5 to 10, and may have a shape that covers at least a part of the periphery of the winding. In the coil unit of this embodiment, the magnetic material should be arranged such that the opposing area remains constant even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes in opposing coil units. Furthermore, the gap between both ends of the magnetic material does not have to be an air region, and a non-magnetic member such as a resin spacer to maintain the positional relationship between the magnetic material and the winding may be placed there.

[0030] Embodiment 2. In the description of the contactless power supply device according to Embodiment 1, k=1, but in the contactless power supply device according to Embodiment 2, k=2. The configuration of the contactless power supply device in this embodiment is the same as the configuration of the contactless power supply device in Embodiment 1, but n １ = 1, n ２ This is based on the assumption that = 3. Therefore, m = 3. Also, k = 2.

[0031] Figure 11 is a bottom view of the coil unit 82A according to this embodiment, and Figure 12 is a top view of the coil unit 82B according to this embodiment. In Figures 11 and 12, the lines used to divide the coil unit into six equal parts at a 60° angle are shown as dashed lines.

[0032] Coil unit 82A has one magnetic material 84A. Coil unit 82B has three magnetic materials 84B. The magnetic material in at least one coil unit is sized to occupy 120° of the angle of one turn of the winding, using equation (1). Here, the magnetic material 84A of coil unit 82A is arranged to occupy 240° (k=2) of the angle of one turn of the winding. The gap 85A is sized to occupy 120° of the angle of one turn of the winding, according to equation (2).

[0033] Each of the magnetic materials 84B of the coil unit 82B can be arbitrarily selected relative to the angle of one turn of the winding, since the angle that the magnetic material 84A of the coil unit 82A occupies relative to the angle of one turn of the winding satisfies the condition shown in equation (1). Here, each of the magnetic materials 84B is arranged to occupy a size of 60° relative to the angle of one turn of the winding. Also, according to equation (2), the gap 85B occupies a size of 60° relative to the angle of one turn of the winding.

[0034] In the non-contact power feeding device of the present embodiment, when the coil units 82A and 82B are configured to face each other about a common axis, it can be seen that the area where the magnetic body 84A and the magnetic body 84B face each other accounts for 120° of the angle corresponding to one turn of the winding. Further, when at least one of the coil units 82A and 82B rotates about the common axis, even if the facing area between one magnetic body 84B and the magnetic body 84A decreases by a certain amount, the facing area between any other one magnetic body 84B and the magnetic body 84A increases by a certain amount. As a result, for the magnetic bodies 84A and 84B, even when k in formula (1) is 2 and the relative positional relationship between the coil units in the rotation direction about the common axis fluctuates, the total facing area can be kept constant.

[0035] As described above, in the non-contact power feeding device of the present embodiment, without increasing the number of magnetic bodies more than necessary, even if the relative positional relationship between the coil units in the rotation direction about the common axis fluctuates, the facing area of the magnetic bodies can be kept constant. Fluctuations in coupling are suppressed, circuit operation is stabilized, and the device is lightweight and low-cost.

[0036] Embodiment 3. In the description of the non-contact power feeding device according to Embodiment 1, n １ =1, n ２ =2 is set, whereas in the non-contact power feeding device according to Embodiment 3, n １ =3, n ２ =6 is set. Therefore, m=6 is obtained. Further, k=1 is set. Furthermore, in the present embodiment, without using part of the magnetic bodies in one of the opposing coil units, even if the relative positional relationship between the coil units in the rotation direction about the common axis fluctuates, the facing area of the magnetic bodies can be kept constant. A non-contact power feeding device that suppresses coupling fluctuations, stabilizes circuit operation, is lightweight and low-cost will be described.

[0037] FIG. 13 is a bottom view of a coil unit 92A according to the present embodiment, and FIG. 14 is a top view of a coil unit 92B according to the present embodiment. In FIGS. 13 and 14, lines for dividing the coil unit into 12 equal parts at an angle of 30° are indicated by dashed-dotted lines.

[0038] The coil unit 92A includes three magnetic bodies 94A. Further, the coil unit 92B includes six magnetic bodies 94B. The magnetic body in at least one of the coil units is sized to occupy 60° relative to the angle of one turn of the winding using formula (1). Here, the magnetic body 94A of the coil unit 92A is sized to occupy 60° (k=1) relative to the angle of one turn of the winding. Further, according to formula (2), the gap 95A is sized to occupy 60° relative to the angle of one turn of the winding.

[0039] For each of the magnetic bodies 94B of the coil unit 92B, since the angle occupied by the magnetic body 94A of the coil unit 92A relative to the angle of one turn of the winding satisfies the condition shown in formula (1), the angle occupied relative to the angle of one turn of the winding can be arbitrarily selected. Here, the magnetic bodies 94B are each arranged to have a size that occupies 30° relative to the angle of one turn of the winding. Further, according to formula (2), the gap 95B is sized to occupy 30° relative to the angle of one turn of the winding.

[0040] It can be seen that, for the magnetic bodies 94A and 94B, when the coil units 92A and 92B are arranged opposite each other about a common axis, the opposing area between the magnetic bodies occupies 90° relative to the angle of one turn of the winding. Further, when at least one of the coil units 92A and 92B rotates about the common axis, even if the opposing area between one magnetic body 94B and one magnetic body 94A decreases by a certain amount, the opposing area between another magnetic body 94B and the magnetic body 94A increases by a certain amount. As a result, for the magnetic bodies 94A and 94B, even if the relative positional relationship between the coil units in the rotational direction about the common axis changes, the total opposing area can be kept constant. At this time, either one of the coil units 92A and 92B is divided for each range represented by formula (3).

[0041] Division range = Least common multiple of 360° / n １ and 360° / n ２ (3)

[0042] Coil unit 92A has 3 magnetic material 94A. Coil unit 92B has 6 magnetic material 94B. Therefore, equation (3) only requires finding the least common multiple of 120° and 60°, and from equation (3), the division range is calculated to be 120°. Here, coil unit 92B is considered as one of the coil units and is divided into three sections at 120° intervals relative to the angle of one turn of the winding. It can be seen that the arrangement of magnetic material 94B and gap 95B is the same in each of the divided ranges.

[0043] Furthermore, we focus on one of the three ranges into which the coil unit 92B is divided at 120° intervals. In the range we focus on, we find that the area of ​​the magnetic materials 94A and 94B facing each other when the coil units 92A and 92B are configured to face each other around the coaxial axis occupies 30° of the angle of one turn of the winding. Also, when at least one of the coil units 92A and 92B rotates around the coaxial axis, even if the area of ​​one magnetic material 94B and magnetic material 94A facing each other decreases by a certain amount, the area of ​​the other magnetic material 94B and magnetic material 94A facing each other increases by a certain amount. As a result, in the range we focus on, the magnetic material 94B can maintain a constant area of ​​facing magnetic material 94A even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0044] Next, we will focus on each of the remaining two ranges that were not considered. In both ranges, it can be seen that the area of ​​magnetic materials 94A and 94B that faces each other when coil units 92A and 92B are configured to face each other around the coaxial axis occupies 30° of the angle of one turn of the winding. Furthermore, when at least one of coil units 92A and 92B rotates around the coaxial axis, even if the area of ​​one magnetic material 94B and magnetic material 94A decreases by a certain amount, the area of ​​the other magnetic material 94B and magnetic material 94A increases by a certain amount. As a result, in each of the remaining two ranges that were not considered, it is possible to keep the area of ​​magnetic material 94B facing magnetic material 94A constant even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0045] Therefore, in each of the three divisions represented by equation (3) at 120° intervals, the opposing area of ​​the magnetic material is constant at 30°. In other words, even if the magnetic material is placed in all but one of the ranges in one of the coil units, the opposing area of ​​the magnetic material remains constant.

[0046] Figure 15 shows an example of a coil unit in which magnetic materials are not placed in two of the three areas divided at 120° intervals in Figure 14. It can be seen that when coil units 92A and 92C are configured to face each other around the coaxial axis, the area in which magnetic materials 94A and 94C face each other occupies 30° of the angle of one turn of the winding. Furthermore, it can be seen that when at least one of coil units 92A and 92C rotates around the coaxial axis, even if the area in which one magnetic material 94C faces magnetic material 94A decreases by a certain amount, the area in which the other magnetic material 94C faces magnetic material 94A increases by a certain amount.

[0047] As described above, in the contactless power supply device of this embodiment, even if a portion of the magnetic material in one of the opposing coil units is not used, the opposing area of ​​the magnetic material can be kept constant even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes, thereby suppressing coupling fluctuations, stabilizing circuit operation, and providing a lightweight and low-cost contactless power supply device.

[0048] Embodiment 4. In the description of the contactless power supply device according to Embodiment 1, n １ = 1, n ２ = 2, but the contactless power supply device according to Embodiment 4 is n １ = 3, n ２ This is set to = 4. Therefore, m = 12. Also, k = 1. Furthermore, in this embodiment, when the magnetic material placed in one coil unit is moved and positioned, even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes, the opposing area of ​​the magnetic material can be kept constant, suppressing coupling fluctuations and stabilizing circuit operation, and a lightweight and low-cost contactless power supply device will be described.

[0049] Figure 16 is a bottom view of the coil unit 102A according to this embodiment, and Figure 17 is a top view of the coil unit 102B according to this embodiment. In Figures 16 and 17, the lines used to divide the coil unit into 12 equal parts at a 30° angle are shown as dashed lines.

[0050] Coil unit 102A has 3 magnetic material 104A. Coil unit 102B has 4 magnetic material 104B. The magnetic material in at least one coil unit is sized to occupy 30° of the angle of one turn of the winding, using equation (1). Here, the magnetic material 104A of coil unit 102A is sized to occupy 30° (k=1) of the angle of one turn of the winding. The gap 105A is sized to occupy 90° of the angle of one turn of the winding, according to equation (2).

[0051] Each of the magnetic materials 104B in the coil unit 102B can be arbitrarily selected relative to the angle of one turn of the winding, since the angle that the magnetic material 104A of the coil unit 102A occupies relative to the angle of one turn of the winding satisfies the condition shown in equation (1). Here, each of the magnetic materials 104B is arranged to occupy an angle of 30° relative to the angle of one turn of the winding. Also, according to equation (2), the gap 105B occupies an angle of 60° relative to the angle of one turn of the winding.

[0052] It can be seen that when coil units 102A and 102B are configured to face each other around the coaxial axis, the area of ​​the magnetic materials 104A and 104B that faces each other occupies 30° of the angle of one turn of the winding. Furthermore, when at least one of the coil units 102A and 102B rotates around the coaxial axis, even if the area of ​​one magnetic material 104B and magnetic material 104A decreases by a certain amount, the area of ​​the other magnetic material 104B and magnetic material 104A increases by a certain amount. As a result, the magnetic materials 104A and 104B can maintain a constant area of ​​face even when the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0053] At this point, we consider moving at least one of the magnetic materials in either coil unit 102A or 102B by the angle represented by equation (4). Here, let p be any natural number.

[0054] Movement angle = 360° / (number of magnetic materials in the other coil unit) × p (4)

[0055] Here, coil unit 102B is considered one of the coil units. The other coil unit 102A has 3 magnetic materials 104A, so if we set p = 1, we can calculate from equation (4) that the movement angle is 120°. We also focus on one arbitrary magnetic material 104B of coil unit 102B. It can be seen that the relative opposition relationship between the focused magnetic material 104B and magnetic material 104A remains the same even when the focused magnetic material 104B is moved by the angle expressed in equation (4).

[0056] Next, we focus on each of the remaining three magnetic materials 104B that we have not yet considered. We can see that the relative opposing relationship between each of the remaining three magnetic materials 104B and magnetic material 104A remains the same even when each of the remaining three magnetic materials 104B is moved by the angle represented by equation (4).

[0057] Therefore, even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes, the surface area facing the magnetic material 104A remains the same as in the original configuration, when the magnetic material 104B is moved and positioned by the angle represented by equation (4). In other words, even if at least one of the magnetic materials in one coil unit is moved to a different position based on equation (4), it is possible to keep the surface area facing the magnetic material in the other coil unit constant, even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0058] Figure 18 is a top view of coil unit 102C when the magnetic material 104B, located in the fourth quadrant of coil unit 102B in Figure 17, is moved by rotating it 120° (p=1) in a clockwise direction. Note that the direction of movement can be either clockwise or counterclockwise. In Figure 18, it can be seen that the magnetic material 104B, which is the object of movement, has been rotated 120° as magnetic material 104C and moved to the second quadrant.

[0059] It can be seen that when coil units 102A and 102C are configured to face each other around the coaxial axis, the area of ​​the magnetic materials 104A and 104C facing each other occupies 30° of the angle of one turn of the winding. Furthermore, when at least one of the coil units 102A and 102C rotates around the coaxial axis, even if the area of ​​one magnetic material 104C and magnetic material 104A decreases by a certain amount, the area of ​​the other magnetic material 104C and magnetic material 104A increases by a certain amount. As a result, the magnetic materials 104A and 104C can maintain a constant area of ​​facing each other even when the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0060] In the contactless power supply device of this embodiment shown in Figures 16 and 18, an example is shown where the natural number p is 1 in the movement angle represented by equation (4). It is also possible to position at least one magnetic material in either coil unit by moving it by a movement angle expressed as 2 or more for the angle of one turn of the winding.

[0061] Figure 19 is a top view of coil unit 102D when the magnetic material 104B, located in the fourth quadrant of coil unit 102B in Figure 17, is moved by rotating it 240° (p=2) clockwise. It can be seen that the magnetic material 104B, which was the object to be moved, has been moved to the first quadrant as magnetic material 104D in Figure 19.

[0062] It can be seen that when coil units 102A and 102D are configured to face each other around the coaxial axis, the area of ​​the magnetic materials 104A and 104D that faces each other occupies 30° of the angle of one turn of the winding. Furthermore, when at least one of the coil units 102A and 102D rotates around the coaxial axis, even if the area of ​​one magnetic material 104D facing magnetic material 104A decreases by a certain amount, the area of ​​the other magnetic material 104D facing magnetic material 104A increases by a certain amount. As a result, the magnetic materials 104A and 104D can maintain a constant area of ​​face even when the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

[0063] As described above, in the contactless power supply device of this embodiment, when at least one of the magnetic materials in one of the opposing coil units is moved to a different position, the opposing area of ​​the magnetic materials can be kept constant even if the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes, thereby suppressing coupling fluctuations, stabilizing circuit operation, and providing a lightweight and low-cost contactless power supply device.

[0064] Although this disclosure describes a magnetic field coupled type contactless power supply device, similar effects can be obtained by applying the configuration of the embodiments and examples of this disclosure to an electric field coupled type contactless power supply device in which the windings of the contactless power supply device described in this disclosure are replaced with electrodes and the magnetic material with a dielectric.

[0065] While this disclosure describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but are applicable individually or in various combinations to the embodiments. Accordingly, countless variations not illustrated are envisioned within the scope of the art disclosed in this specification. For example, these include modifying, adding or omitting at least one component, or even extracting at least one component and combining it with a component from another embodiment.

[0066] 11. Contactless power supply devices: 12A, 12B, 22, 32, 42, 52, 62, 72, 82A, 82B, 92A, 92B, 92C, 102A, 102B, 102C, 102D. Coil units: 13A, 13B, 33, 43, 53, 63, 73, 93A, 93B, 93C, 103A, 103B, 103C, 103D. Windings: 14A, 14B, 24, 34, 44, 54, 64, 74, 84A, 84B, 94A, 94B, 94C, 104A, 104B, 104C, 104D Magnetic material, 15A, 15B, 35, 45, 85A, 85B, 95A, 95B, 105A, 105B, 105C, 105D Gap.

Claims

1. A contactless power supply device comprising two coil units, each having an annular winding and at least one magnetic material covering a portion of the winding, wherein the coil units are arranged facing each other around a coaxial axis, the number of magnetic materials in one coil unit is different from the number of magnetic materials in the other coil unit, and the magnetic materials are arranged with a certain gap between them in order to keep the opposing area of ​​the magnetic materials between the coil units constant when the relative positional relationship between the coil units in the rotational direction around the coaxial axis changes.

2. A contactless power supply device comprising two coil units, each having an annular winding and at least one magnetic material covering a portion of the winding, wherein the coil units are arranged opposite each other around a coaxial axis, and the magnetic materials are arranged in each coil unit at a certain angle with respect to the angle of one full turn of the winding and with a certain gap between them, and the number of magnetic materials in one of the coil units is n １ The number of magnetic materials in the other coil unit is n. ２ When n １ to n ２ n are different numbers. １ to n ２ A contactless power supply device characterized in that, when m and k are natural numbers and the least common multiple of the two, the angle occupied by the magnetic material of at least one of the coil units is given by the value obtained by integrating k with 360° / m.

3. When an angle occupied by the magnetic body of one of the coil units is W １ and an angle occupied by the magnetic body of the other coil unit is W ２ , an angle occupied by the gap of said one coil unit is given by 360° / n １ - W １ , and an angle occupied by the gap of said other coil unit is given by 360° / n ２ - W ２ , the non-contact power feeding device according to claim 2, characterized in that:

4. The contactless power supply device according to claim 2 or 3, characterized in that a non-magnetic member is placed in the gap between at least one of the coil units.

5. Either of the coil units is 360° / n １ and 360° / n ２ The contactless power supply device according to any one of claims 2 to 4, characterized in that the magnetic material is arranged in regions excluding at least one of a plurality of regions divided by angles represented by the least common multiple of the two.

6. The contactless power supply device according to any one of claims 2 to 5, characterized in that at least one of the magnetic materials of one of the coil units is positioned at a location where it has been rotated around the coaxial axis by an angle obtained by multiplying the value obtained by dividing 360° by the number of magnetic materials of the other coil unit by p, with p being a natural number.

7. The contactless power supply device according to any one of claims 1 to 6, characterized in that the magnetic material covers at least a portion of the area around the winding.

8. The contactless power supply device according to any one of claims 1 to 7, characterized in that the magnetic material of at least one of the coil units is fan-shaped or has a shape that covers only the portion of the winding.

9. The contactless power supply device according to any one of claims 1 to 8, characterized in that the magnetic material of at least one of the coil units is composed of a combination of one or more magnetic materials.

Images