The present invention relates to a reactor having an outer peripheral iron core and iron core coils.
Reactors include a plurality of iron core coils, and each iron core coil includes an iron core and a coil wound onto the iron core. Predetermined gaps are formed between the plurality of iron cores. Refer to, for example, Japanese Unexamined Patent Publication (Kokai) No. 2000-77242 and Japanese Unexamined Patent Publication (Kokai) No. 2008-210998.
There are also reactors in which a plurality of iron core coils are arranged inside an annular outer peripheral iron core. In such reactors, the outer peripheral iron core can be divided into a plurality of outer peripheral iron core portions, and the iron cores may be formed integrally with the respective outer peripheral iron core portions.
However, since the outer peripheral iron core is divided into a plurality of outer peripheral iron core portions, when the reactor is driven, vibrations may be generated due to magnetostriction or the like, and the plurality of outer peripheral iron core portions may become misaligned with each other. In this case, there is a risk that the desired magnetic properties may not be obtained. Furthermore, when the periphery of the outer peripheral iron core is surrounded and connected with a band made from an elastic body, there is a problem in that the size of the reactor increases.
Thus, a reactor in which misalignment of the plurality of outer peripheral iron core portions due to magnetostriction can be prevented without an increase in the size of the reactor is desired.
According to the first aspect of the present disclosure, there is provided a reactor comprising an outer peripheral iron core composed of a plurality of outer peripheral iron core portions, and at least three iron core coils arranged inside the outer peripheral iron core, wherein the at least three iron core coils are composed of iron cores coupled with the respective outer peripheral iron core portions and coils wound onto the respective iron cores, and gaps, which can be magnetically coupled, are formed between one of the at least three iron cores and another iron core adjacent thereto, the reactor further comprising connection parts for connecting the plurality of outer peripheral iron core portions to each other.
In the first aspect, since the plurality of outer peripheral iron core portions are connected by the connection parts, it is possible to prevent the plurality of outer peripheral iron core portions from becoming misaligned due to magnetostriction.
The object, features, and advantages of the present invention, as well as other objects, features and advantages, will be further clarified by the detailed description of the representative embodiments of the present invention shown in the accompanying drawings.
The embodiments of the present invention will be described below with reference to the accompanying drawings. In the following drawings, the same components are given the same reference numerals. For ease of understanding, the scales of the drawings have been appropriately modified.
In the following description, a three-phase reactor will be mainly described as an example. However, the present disclosure is not limited in application to a three-phase reactor but can be broadly applied to any multiphase reactor requiring constant inductance in each phase. Further, the reactor according to the present disclosure is not limited to those provided on the primary side or secondary side of the inverters of industrial robots or machine tools but can be applied to various machines.
Note that the outer peripheral iron core 20 may have another rotationally-symmetrical shape, such as a circular shape. Furthermore, the number of the iron core coils may be a multiple of three, whereby the reactor 6 can be used as a three-phase reactor. As can be understood from the drawings, the iron core coils 31 to 33 include iron cores 41 to 43 extending in the radial directions of the outer peripheral iron core 20 and coils 51 to 53 wound onto the iron cores 41 to 43, respectively.
The outer peripheral iron core 20 is composed of a plurality of, for example, three, outer peripheral iron core portions 24 to 26 divided in the circumferential direction. The outer peripheral iron core portions 24 to 26 are formed integrally with the iron cores 41 to 43, respectively. The outer peripheral iron core portions 24 to 26 and the iron cores 41 to 43 are formed by stacking a plurality of magnetic plates, such as iron plates, carbon steel plates, electromagnetic steel plates, or the like. When the outer peripheral iron core 20 is composed of a plurality of outer peripheral iron core portions 24 to 26, even if the outer peripheral iron core 20 is large, such an outer peripheral iron core 20 can be easily manufactured. Note that the number of iron cores 41 to 43 and the number of iron core portions 24 to 26 need not necessarily be the same.
The coils 51 to 53 are arranged in coil spaces 51a to 53a formed between the outer peripheral iron core portions 24 to 26 and the iron cores 41 to 43, respectively. In the coil spaces 51a to 53a, the inner peripheral surfaces and the outer peripheral surfaces of the coils 51 to 53 are adjacent to the inner walls of the coil spaces 51a to 53a.
Further, the radially inner ends of the iron cores 41 to 43 are each located near the center of the outer peripheral iron core 20. In the drawing, the radially inner ends of the iron cores 41 to 43 converge toward the center of the outer peripheral iron core 20, and the tip angles thereof are approximately 120 degrees. The radially inner ends of the iron cores 41 to 43 are separated from each other via gaps 101 to 103, which can be magnetically coupled.
In other words, the radially inner end of the iron core 41 is separated from the radially inner ends of the two adjacent iron cores 42 and 43 via gaps 101 and 103. The same is true for the other iron cores 42 and 43. Note that, the sizes of the gaps 101 to 103 are equal to each other.
In the configuration shown in
Further, in the core body 5 of the present disclosure, the difference in the magnetic path lengths is reduced between the phases, as compared to conventionally configured reactors. Thus, in the present disclosure, the imbalance in inductance due to a difference in magnetic path length can be reduced.
Additionally, since the gaps are inevitably provided at locations far from the coils, the leakage of magnetic flux from the gaps makes it difficult to interlink the coils. Furthermore, since the angles between the iron cores of the adjacent iron core coils is less than 180 degrees, spreading of magnetic flux from the vicinity of the gaps is suppressed. As a result of these effects, it is difficult to interlink the coils due to the leakage of flux, and the eddy current losses of the coils due to the leakage of magnetic flux can be suppressed.
As can be understood from
The magnetic plates 24a include projecting portions 70b projecting toward the outer peripheral iron core portion 26 (not shown in
Further, the magnetic plates 25a of the outer peripheral iron core portion 25 have the same shape as the magnetic plates 24a of the outer peripheral iron core portion 24, and the magnetic plates 25b have the same shape as the magnetic plates 24b of the outer peripheral iron core portion 24. Though not shown in the drawings, the outer peripheral iron core portion 26 is composed of similar magnetic plates 26a, 26b.
As shown in
In this connection, in the first embodiment, since the plurality of outer peripheral iron cores 24 to 26 can be connected to each other by the intermeshing portions 70 as connection parts, misalignment of the plurality of outer peripheral iron core portions 24 to 26 due to magnetostriction can be prevented. Furthermore, since additional members or the like are not needed, it is possible to prevent an increase in size of the reactor 6. Further, for the same reason, when connecting the plurality of outer peripheral iron core portions 24 to 26 by the intermeshing portions 70, the influence on the magnetic properties of the reactor 6 at the time of energization can be reduced.
Further, even if minute clearances are formed between, for example, the plurality of magnetic plates 24a of the outer peripheral iron core portion 24 and the plurality of magnetic plates 25a of the outer peripheral iron core portion 25, other magnetic plates 24b, 25b are present between the plurality of magnetic plates 24a and between the plurality of magnetic plates 25a, respectively. Thus, the influence of such minute gaps on the magnetic properties can be minimized.
In
As can be understood with reference to
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Thereafter, by forming the intermeshing portion 70 as shown in
Further,
In the third embodiment, by forming the intermeshing portions 70 as described above, the through-hole 91 is formed from the recess parts 96a and 96b. The connection member 81, which is the same as described above, is inserted into and fitted in the through-hole 91. The same is true for the other through-holes 92 and 93. In this case, the outer peripheral iron core portion 24 and the outer peripheral iron core portion 25 can be more firmly fastened. Further, in the third embodiment, it can be understood that the same effects as described above can be obtained. Note that the shapes of the recess parts 96a, 96b are not limited to those described above.
Alternatively, it is preferable that the portions corresponding to the connection members 81 to 83 be punched from a plurality of stacked magnetic plates to thereby form the connection members 81 to 83. The portions corresponding to the outer peripheral iron core portions 24 to 26 integrally formed with the iron cores 41 to 43 may be punched from the stacked magnetic plates. In this case, it is not necessary to prepare additional members in order to form the connection members 81 to 83. However, the connection members 81 to 83 may be separately formed as single members.
Furthermore, when the connection members 81 to 83 are formed from a plurality of magnetic plates, the connection members 81 to 83 are magnetic materials. In contrast thereto, when the connection members are formed from a non-magnetic material, the magnetic properties of the reactor 6 at the locations of the connection members are influenced by the connection members, whereby magnetic flux saturation is promoted. However, when the connection members 81 to 83 are formed from a magnetic material, such a problem can be avoided.
As shown in
As shown in
As can be understood from the drawing, the iron core coils 31 to 34 include iron cores 41 to 44 extending in the radial directions and coils 51 to 54 wound onto the respective iron cores, respectively. The radially outer ends of the iron cores 41 to 44 are integrally formed with the respective outer peripheral iron core portions 24 to 27.
Further, each of the radially inner ends of the iron cores 41 to 44 is located near the center of the outer peripheral iron core 20. In
In
According to the first aspect, there is provided a reactor (6), comprising an outer peripheral iron core (20) composed of a plurality of outer peripheral iron core portions (24 to 27), and at least three iron core coils (31 to 34) arranged inside the outer peripheral iron core, wherein the at least three iron core coils are composed of iron cores (41 to 44) coupled with the respective outer peripheral iron core portions and coils (51 to 54) wound onto the respective iron cores, and gaps (101 to 104), which can be magnetically coupled, are formed between one of the at least three iron cores and another iron core adjacent thereto, the reactor further comprising connection parts (70) for connecting the plurality of outer peripheral iron core portions to each other.
According to the second aspect, in the first aspect, the outer peripheral iron core portions and the iron core are formed by stacking a plurality of plates in a stacking direction.
According to the third aspect, in the first or second aspect, the connection parts include intermeshing portions (70) in which a plurality of plates of one outer peripheral iron core portion and a plurality of plates of another outer peripheral iron core portion project in a staggered manner and intermesh with each other between the outer peripheral iron core portions which are adjacent to each other.
According to the fourth aspect, in the third aspect, holes (91 to 94) are formed between the plurality of outer peripheral iron core portions or in the intermeshing portions, and the connection parts further include connection members (81 to 84) which are inserted into the holes.
According to the fifth aspect, in the fourth aspect, the connection members are formed by stacking a plurality of plates in the stacking direction, and the connection members are shifted with respect to the plurality of plates constituting the plurality of outer peripheral iron core portions in the stacking direction by a distance smaller than the thickness of one of the plurality of plates.
According to the sixth aspect, in the fourth or fifth aspect, the connection members are formed from a magnetic material.
According to the seventh aspect, in any one of the first through sixth aspects, the number of the at least three iron core coils is a multiple of three.
According to the eighth aspect, in any of the first through sixth aspects, the number of the at least three iron core coils is an even number not less than four.
In the first aspect, since the plurality of outer peripheral iron core portions are connected by the connection parts, it is possible to prevent the plurality of outer peripheral iron core portions from becoming misaligned due to magnetostriction.
In the second aspect, the outer peripheral iron core portions and the iron cores can be easily assembled.
In the third aspect, the plurality of outer peripheral iron core portions can be easily connected by the intermeshing portions. Furthermore, disassembly and reassembly of the reactor is easy.
In the fourth aspect, by using connection members, since the connection members are inserted into the holes, the plurality of outer peripheral iron core portions can be firmly connected, and it is possible to prevent the size of the reactor from increasing.
In the fifth aspect, since the connection members are shifted in the stacking direction, the plurality of outer peripheral iron core portions can be firmly connected to each other with a simple configuration.
Furthermore, since the connection members and the plurality of outer peripheral iron core portions can be produced by punching a plurality of stacked plates, it is not necessary to prepare additional members in order to produce the connection members.
When the connection members are made from a non-magnetic material, the magnetic properties of the reactor at the locations of the connection members tend to be influenced by the connection members, thus resulting in the occurrence of magnetic flux saturation. In the sixth aspect, since the connection members are formed from a magnetic material, such a problem can be avoided.
In the seventh aspect, the reactor can be used as a three-phase reactor.
In the eighth aspect, the reactor can be used as a single-phase reactor.
Though the present invention has been described using representative embodiments, a person skilled in the art would understand that the foregoing modifications and various other modifications, omissions, and additions can be made without departing from the scope of the present invention.
Number | Date | Country | Kind |
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2017-131362 | Jul 2017 | JP | national |