CONTACTLESS POWER SUPPLY COIL UNIT
20190207433 ยท 2019-07-04
Inventors
Cpc classification
H01F27/006
ELECTRICITY
H02J50/005
ELECTRICITY
H02J50/402
ELECTRICITY
H01F2027/2842
ELECTRICITY
International classification
Abstract
A contactless power supply coil unit includes coils wound around a center axis and a holder that holds the coils. The coils are spirally wound in plan view and overlap in an axial direction and respectively define layers stacked in the axial direction. The coils defining adjacent layers are connected in series to each other. The holder includes a core extending in the axial direction. The core includes a winding portions disposed along the axial direction. The coils are respectively wound around the winding portions. The outer diameters of the winding portions each change monotonically along the axial direction.
Claims
1-8. (canceled)
9. A contactless power supply coil unit comprising: a plurality of coils that are wound around a predetermined center axis; and a holder that holds the plurality of coils; wherein the coils are spirally wound in plan view; the plurality of coils are disposed so as to overlap in an axial direction and respectively define layers stacked in the axial direction; the coils defining adjacent layers are connected in series to each other; the holder includes a core extending in the axial direction; the core includes a plurality of winding portions disposed along the axial direction; the plurality of the coils are respectively wound around the plurality of winding portions; and outer diameters of the plurality of winding portions each change monotonically along the axial direction.
10. The contactless power supply coil unit according to claim 9, wherein the winding portions include: first winding portions in which an outer diameter of the core decreases from one axial-direction side toward the other axial-direction side; and second winding portions in which the outer diameter of the core increases from the one axial-direction side toward the other axial-direction side; the first winding portion and the second winding portion are provided alternately along the axial direction.
11. The contactless power supply coil unit according to claim 10, wherein the winding portions that are adjacent to each other in the axial direction are connected to each other, and the outer diameters of the winding portions that are adjacent to each other in the axial direction are same at points of connection to each other.
12. The contactless power supply coil unit according to claim 9, wherein each of the plurality of winding portions is a separate independent structural member.
13. The contactless power supply coil unit according to claim 9, wherein the holder includes a cylindrical structure that has a cylindrical shape and that surrounds the core from a radial-direction outer side of the coils; a shape of a radial-direction-inner-side surface of the cylindrical portion extends along a radial-direction-outer-side surface of the core.
14. The contactless power supply coil unit according to claim 13, wherein the cylindrical structure includes a plurality of cylindrical portions respectively surrounding the winding portions, the plurality of cylindrical portions being separate independent structural members, and the cylindrical portions being defined by a plurality of cylindrical portion pieces connected to each other and divided in a circumferential direction.
15. The contactless power supply coil unit according to claim 9, wherein the winding portions respectively include grooves recessed from a radial-direction outer side surface toward a radial-direction inner side, the grooves extending along a circumferential direction, and the coils being wound along the grooves, respectively.
16. The contactless power supply coil unit according to claim 9, wherein the winding portions have a truncated cone shape extending in the axial direction.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0006]
[0007]
[0008]
[0009]
[0010]
[0011]
[0012]
DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS
[0013] As illustrated in
[0014] The plurality of coils 50 are disposed so as to overlap in the axial direction and respectively form layers F stacked in the axial direction. The coils 50 of the present example embodiment are, for example, provided as five coils, namely, a first coil 51 to a fifth coil 55. Five layers F formed by the first coil 51 to the fifth coil 55, namely, a first layer F1 to a fifth layer F5, are provided. The first coil 51 forms the first layer F1. A second coil 52 forms a second layer F2. A third coil 53 forms a third layer F3. A fourth coil 54 forms a fourth layer F4. The fifth coil 55 forms the fifth layer F5. The first coil 51, the second coil 52, the third coil 53, the fourth coil 54, and the fifth coil 55 are disposed in this order from the lower side to the upper side.
[0015] As illustrated in
[0016] As illustrated in
[0017] As illustrated in
[0018] As illustrated in
[0019] As described above, the outer diameters of the plurality of winding portions 30a monotonically change along the axial direction. In the present specification, the outer diameter of the winding portion monotonically changes along the axial direction includes the meaning that, for a single winding portion, the change in the outer diameter of the winding portion along one axial direction can be an increase or a decrease. Specifically, the outer diameters of the first winding portions 31, 33, and 35 of the present example embodiment decrease monotonically from the lower side to the upper side. The outer diameters of the second winding portions 32 and 34 increase monotonically from the lower side to the upper side.
[0020] In addition, in the present specification, the outer diameter of the winding portion monotonically changes along the axial direction includes the meaning that, for a single winding portion, the winding portion includes a portion having an outer diameter that does not change partly along the axial direction. That is, for example, in the first winding portion 31, the outer diameter of which monotonically decreases from the lower side to the upper side, a portion that extends in the axial direction without changing the outer diameter may be provided. In addition, the rate of change of the outer diameter of the winding portion need not be monotonic. In the present example embodiment, the outer diameter of the winding portion 30a changes monotonically with a constant rate of change along the axial direction.
[0021] The first winding portion 31, the second winding portion 32, the first winding portion 33, the second winding portion 34, and the first winding portion 35 extend from the lower side to the upper side in this order. That is, the first winding portions 31, 33, and 35 and the second winding portions 32 and 34 are provided alternately along the axial direction. The winding portions 30a that are adjacent in the axial direction are connected to each other. The outer diameters of the winding portions 30a adjacent in the axial direction are the same at the portions at which the winding portions 30a are connected to each other. More specifically, for example, the outer diameter of the portion where the first winding portion 31 and the second winding portion 32 are connected to each other, that is, the outer diameter of the upper end of the first winding portion 31 and the outer diameter of the lower end of the second winding portion 32 are the same. The outer diameter of the portion where the second winding portion 32 and the first winding portion 33 are connected to each other, that is, the outer diameter of the upper end of the second winding portion 32 and the outer diameter of the lower end of the first winding portion 33 are the same. In the present example embodiment, the outer diameter of the core member 30 is a shape that periodically changes between the maximum value and the minimum value of the outer diameters of the winding portions 30a along the axial direction.
[0022] Further, in the present specification, the phrase the outer diameters of the winding portions are the same means that, in addition to the case where the outer diameters of the winding portions are strictly the same, it includes the case where the outer diameters are substantially the same.
[0023] The plurality of coils 50 are respectively wound around the plurality of winding portions 30a. Specifically, the first coil 51 is wound around the first winding portion 31. The second coil 52 is wound around the second winding portion 32. The third coil 53 is wound around the first winding portion 33. The fourth coil 54 is wound around the second winding portion 34. The fifth coil 55 is wound around the first winding portion 35. The coils 50 are respectively wound in the circumferential direction along the outer peripheral surfaces of the winding portions 30a. The axial positions at which the coils 50 in the winding portions 30a are respectively wound sequentially change in the axial direction each time the coils 50 are wound. In the present example embodiment, the coils 50 are respectively spirally wound around the outer peripheral surfaces of the winding portions 30a.
[0024] As illustrated in
[0025] According to the present example embodiment, the outer diameters of the winding portions 30a change monotonically along the axial direction. A conductive wire is wound in the circumferential direction along the outer peripheral surfaces of the winding portions 30a. By sequentially changing the winding position of the conductive wire in the axial direction, it is possible to easily manufacture the coils 50 having a spiral shape in plan view. In addition, the axial interval between the winding start and the winding end of the coils 50 can be increased by the axial-direction dimension of the winding portions 30a.
[0026] Here, when the conductive wire forming the coils 50 starts to be wound from the first coil 51, the potential difference between the coils 50 of the adjacent layers F is greatest between the winding start of the coil 50 on the lower side and the winding end of the coil 50 on the upper side among the coils 50 that are adjacent to each other in the axial direction. Specifically, the potential difference between the first coil 51 and the second coil 52 becomes largest between the winding start of the first coil 51 and the winding end of the second coil 52. That is, by increasing the interval D1 between the winding start of the first coil 51 and the winding end of the second coil 52 illustrated in
[0027] In the present example embodiment, the winding start of the first coil 51 is the lower end of the first winding portion 31 and the winding end of the second coil 52 is the upper end of the second winding portion 32. That is, as illustrated in
[0028] In addition, when the number of coils connected in series is increased, the potential difference between the coil on one end side and the coil on the other end side increases. Therefore, there is a case where the intervals between the coils that are adjacent to each other cannot be made sufficiently large with respect to the potential difference between the coil on one end side and the coil on the other end side.
[0029] On the other hand, according to the present example embodiment, because the intervals D1 to D4 between the coils 50 that are adjacent to each other can be increased, the intervals between the coils 50 can also be increased. In other words, the potential difference becomes largest between the winding start of the first coil 51 and the winding end of the fifth coil 55, but the interval between the winding start of the first coil 51 and the winding end of the fifth coil 55 can be increased by an amount corresponding to the sum of the axial-direction dimensions of the five winding portions 30a. Therefore, even when the number of the coils 50 connected in series is increased, the occurrence of a discharge phenomenon can be suppressed. Therefore, the number of the coils 50 connected in series can be increased, and the amount of electric power that can be transmitted by the contactless power supply device in which the non-contact power supply coil unit 10 is mounted can be increased.
[0030] In addition, according to the present example embodiment, the first winding portions 31, 33, and 35 and the second winding portions 32 and 34 are alternately provided along the axial direction. For example, when winding starts from the first coil 51, the first coil 51 is produced by winding a conductive wire from the lower end to the upper end of the first winding portion 31. In this case, the first coil 51 that has a spiral shape is wound from the radial-direction outer side to the radial-direction inner side. On the other hand, when the second coil 52 is manufactured by winding the conductive wire from the lower end to the upper end of the second winding portion 32, the second coil 52, which has a spiral shape, is wound from the radial-direction inner side to the radial-direction outer side. Therefore, when the coils 50 are manufactured by being wound sequentially along the axial direction, the winding start position can be alternated between the radial-direction inner side and the radial-direction outer side. As a result, after winding the first coil 51 from the radial-direction outer side to the radial-direction inner side, because it is possible to start winding the second coil 52 from the radial-direction inner side as is, the winding of the plurality of coils 50 is facilitated.
[0031] In addition, according to the present example embodiment, the outer diameters of the winding portions 30a that are adjacent to each other in the axial direction are the same at the portions at which the winding portions 30a are connected to each other. Therefore, after winding the first coil 51, it is possible to start winding the second coil 52 with the coil diameter as is, so it is easy to wind the coils 50 continuously.
[0032] In addition, according to the present example embodiment, the shape of each of the winding portions 30a is a truncated cone shape extending in the axial direction. Therefore, it is easy to wind the coils 50 around the winding portions 30a.
[0033] In the present example embodiment, each of the plurality of winding portions 30a is a separate member. Therefore, it is possible to employ a method in which one of the coils 50 is wound around one of the winding portions 30a, then another one of the winding portions 30a is connected and the next one of the coils 50 is wound. Therefore, as compared with the case where the core member 30 is a single member, it is easy to wind the plurality of coils 50.
[0034] As illustrated in
[0035] As illustrated in
[0036] As illustrated in
[0037] Each of the cylindrical portions 40a is formed by connecting a plurality of cylindrical portion pieces divided in the circumferential direction. In the present example embodiment, each of the cylindrical portions 40a is formed by connecting two cylindrical portion pieces 41 and 42. Therefore, as illustrated in
[0038] As illustrated in
[0039] Although not illustrated, the holding member 20 has a magnetic core. The magnetic core extends in the axial direction and is made to pass through the coils 50. For example, the magnetic core is embedded and fixed in the core member 30. The magnetic core is, for example, a ferrite core. By providing the magnetic core, it is possible to improve the power transmission efficiency of the contactless power supply device in which the contactless power supply coil unit 10 is mounted.
[0040] Next, a method of assembling the contactless power supply coil unit 10 of the present example embodiment will be described. As illustrated in
[0041] The assembler fixes a lower surface 32c of the second winding portion 32 to an upper surface 31c of the first winding portion 31 and fixes the first winding portion 31 and the second winding portion 32 to each other. Then, the assembler turns the assembly, in which the first winding portion 31, the first coil 51, the cylindrical portion 40a, and the second winding portion 32 are assembled, upside down. As illustrated in
[0042] The present disclosure is not limited to the example embodiments described above, and other configurations may be adopted. Some of the intervals D1 to D4 between the coils 50 that are adjacent in the axial direction may be different values or all of them may be different from each other. The intervals between the coils 50 that are adjacent to each other in the axial direction may be increased as the intervals are located progressively toward the upper side. That is, the interval D1, the interval D2, the interval D3 and the interval D4 may increase in this order. According to this configuration, because the intervals between the coils 50 having a larger potential difference can be further increased, the occurrence of a discharge phenomenon can be further suppressed. In addition, the number of the coils 50 may be two or more, four or less, or six or more.
[0043] In addition, the plan view shape of the coils 50 is not particularly limited as long as the coils 50 are wound around the center axis J, and may be an elliptical annular shape or a polygonal annular shape. In addition, the plan view shape of the core member 30 and the plan view shape of the winding portions 30a can be appropriately changed in accordance with the plan view shape of the coils 50.
[0044] In addition, all of the plurality of winding portions 30a may be the first winding portions, or all of the plurality of winding portions 30a may be the second winding portions. In addition, the shape of the winding portions 30a is not particularly limited as long as the outer diameter monotonically changes along the axial direction. In addition, the number of the winding portions 30a may be two or more, four or less, or six or more. The groove extending in the circumferential direction of the winding portion 30a may be provided in a plurality along the axial direction. In addition, the groove extending in the circumferential direction of the winding portion 30a may be provided in a plurality along the circumferential direction. In addition, the winding portions 30a need not be provided.
[0045] In addition, each of the plurality of cylindrical portions 40a may be a single member. In addition, each of the cylindrical members 40 may be a single member. In addition, the cylindrical members 40 may be formed by connecting a single member, in which a plurality of the cylindrical portion pieces 41 are connected to each other in the axial direction, and a single member, in which a plurality of cylindrical portion pieces 42 are connected to each other in the axial direction, to each other. In addition, the cylindrical members need not be provided.
[0046] The application of the contactless power supply apparatus in which the contactless power supply coil unit is mounted according to the above example embodiment is not particularly limited, and may be used, for example, for power supply for an automatic guided vehicle.
[0047] Each of the above-described configurations can be appropriately combined to the extent they are not inconsistent with each other.
Feature 1
[0048] A contactless power supply coil unit includes a plurality of coils that are wound around a predetermined center axis and a holding member that holds the plurality of coils, the coils being spirally wound in plan view, the plurality of coils being disposed so as to overlap in an axial direction and respectively forming layers stacked in the axial direction, the coils forming adjacent layers being connected in series to each other, the holding member including a core member extending in the axial direction, the core member including a plurality of winding portions disposed along the axial direction, the plurality of coils being respectively wound around the plurality of winding portions, and the outer diameters of the plurality of winding portions each changing monotonically along the axial direction.
Feature 2
[0049] In the contactless power supply coil unit according to Feature 1, the winding portions may include first winding portions in which the outer diameter of the core member decreases from one axial-direction side toward the other axial-direction side and second winding portions in which the outer diameter of the core member increases from the one axial-direction side toward the other axial-direction side, the first winding portions and the second winding portions being provided alternately along the axial direction.
Feature 3
[0050] In the contactless power supply coil unit according to Feature 2, the winding portions that are adjacent to each other in the axial direction may be connected to each other, and the outer diameters of the winding portions that are adjacent to each other in the axial direction may be the same at the portions where they are connected to each other.
Feature 4
[0051] In the contactless power supply coil unit according to any one of Features 1 to 3, each of the plurality of winding portions may be a separate member.
Feature 5
[0052] In the contactless power supply coil unit according to any one of Features 1 to 4, the holding member may have a cylindrical member that has a cylindrical shape and that surrounds the core member from the radial-direction outer side of the coils, and the shape of the radial-direction-inner-side surface of the cylindrical member is a shape along the radial-direction-outer-side surface of the core member.
Feature 6
[0053] In the contactless power supply coil unit according to Feature 5, the cylindrical member may include a plurality of cylindrical portions respectively surrounding the winding portions, the plurality of cylindrical portions being separate members, and the cylindrical portions being formed by connecting a plurality of cylindrical portion pieces divided in a circumferential direction.
Feature 7
[0054] In the contactless power supply coil unit according to any one of Features 1 to 6, the winding portions may respectively have grooves recessed from a radial-direction outer side surface toward the radial-direction inner side, the grooves extending along the circumferential direction, and the coils being wound along the grooves, respectively.
Feature 8
[0055] In the contactless power supply coil unit according to any one of Features 1 to 7, the shape of the winding portions may be a truncated cone shape extending in the axial direction.
[0056] While example embodiments of the present disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure, therefore, is to be determined solely by the following claims.