The present invention relates to a reactor having iron cores and 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.
In such reactors, the coils portions which project from an end surface of the core body in the axial direction of the core body. When the core body is arranged between an annular pedestal and an end plate, there is a problem in that the projection portions of the coils passing through the pedestal and/or the end plate may become damaged due to interference with foreign matter or the like.
Thus, a reactor in which damage to the coils can be prevented is desired.
According to a first aspect of the present disclosure, there is provided a reactor comprising a core body, the core body comprising an outer peripheral iron core, at least three iron cores arranged in contact with or coupled to an inner surface of the outer peripheral iron core, and at least three coils wound onto the at least three iron cores, wherein 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 a protection part which at least partially protects projection portions of the at least three coils which project from at least one end surface of the core body.
In the first aspect, since the projection portions of the coils are protected by the protection part, damage to the coils can be prevented.
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.
An annular projecting part 61 having an outer shape corresponding to that of the end surface of the core body 5 is provided on the pedestal 60. Through-holes 60a to 60c which penetrate the pedestal 60 are formed in the projecting part 61 at equal intervals in the circumferential direction. The end plate 81 has a similar outer shape, and through-holes 81a to 81c are formed in the end plate 81 at equal intervals in the circumferential direction. The heights of the projection part 61 of the pedestal 60 and the end plate 81 are made longer than the projecting height of the coils 51 to 53 projecting from the end of the core body 5, as will be described later.
The terminal block 65 includes a plurality of, for example, six terminals. The plurality of terminals are connected to a plurality of leads extending from the coils 51 to 53. Through-holes 65a to 65c are formed in the terminal block 65 at equal intervals in the circumferential direction.
Note that the outer peripheral iron core 20 may have other rotationally-symmetrical shapes, such as a circular shape. In such a case, the outer peripheral iron core 20 has a shape corresponding to the terminal block 65, the end plate 81, and the pedestal 60. 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 drawing, 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 iron plates, carbon steel plates, or electromagnetic steel sheets, or are formed from dust cores. 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 the iron cores 41 to 43 and the number of the iron core portions 24 to 26 need not necessarily be the same. Furthermore, through-holes 29a to 29c are formed in the outer peripheral iron core portions 24 to 26.
The coils 51 to 53 are arranged in coil spaces 51a to 53a (“coil spaces 51a to 54a” in the second embodiment, which is described later) 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 the 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.
The protection part 70 may be a single member, or alternatively, may be composed of a plurality of protection members 71 to 73 for protecting the respective coils 51 to 53. Furthermore, the protection part 70 is preferably formed from a rigid non-magnetic material, such as aluminum, SUS, or a resin. In this case, it is possible to prevent the magnetic field from passing through the protection part 70 when the reactor 6 is energized.
The cover member 73a and the insertion member 73b extend parallel to each other toward the radially outer side of the core body 5. A clearance 73d between the cover member 73a and the insertion member 73b is formed corresponding to one portion of the projection portion 53a of the coil 53. The radial inner ends of the cover member 73a and the insertion member 73b are connected to a connection member 73e and supported in a cantilever manner.
The cover member 73a preferably covers at least the furthest portion of the projection portion 53a of the coil 53. In this case, when the core body 5, to which the protection member 73 and/or the other protection members 71, 72 are attached, is mounted on the floor or the like, damage to the coil 53 and/or the other coils 51, 52 can be prevented. Naturally, the cover member 73a may cover the entirety of the projection portion 53a of the coil 53.
Further, the protection member 73 includes an abutment member 73c which is arranged more radially inward of the core body 5 than the cover member 73a and the insertion member 73b. The tip of the abutment member 73c converges to form a predetermined angle. The value of the predetermined angle is determined by dividing 360° by the number of the iron cores 41 to 43 and is equal to the tip angles of the iron cores 41 to 43, for example, 120°.
The two surfaces constituting the tip of the abutment member 73c are the abutment surfaces 93a and 93b, which are described later.
The other protection members 71, 72 are similarly composed, and include cover members 71a, 72a, insertion members 71b, 72b, abutment members 71c, 72c, clearances 71d, 72d, and connection members 71e, 72e, respectively. Further, the abutment members 71c, 72c include respective abutment surfaces 91a, 91b, 92a, 92b.
Alternatively, after attaching the coil 53 to the iron core 43, which is integral with the outer peripheral iron core portion 26, the protection member 73 may be attached to the coil 53. The protection members 71, 72 are similarly attached to the iron cores 41, 42 onto which the coils 51, 52 have been attached, and thereafter, the iron cores 41 to 43 may be assembled to form the core body 5. In that case, when the protection members 71 to 73 are attached to the coils 51 to 53, it is possible to prevent the protection members 71 to 73 from interfering with the other protection members, so that installation difficulty can be avoided
Since the above-mentioned clearance 73d of the protection member 73 is formed corresponding to one portion of the projection portion 53a of the coil 53, both the surface of the cover member 73a adjacent to the coil 53 and the surface of the insertion member 73b adjacent to the coil 53a are curved surfaces curving from the horizontal plane toward the vertical plane. By retaining the coil 53 between these curved surfaces, movement of the coil 53 in the axial direction (direction A1) and the circumferential direction (direction A3) of the reactor 6 when the reactor 6 is energized can be prevented.
Further, the coil 53 is interposed between the inner surface of the outer peripheral iron core portion 26 and the surface of the connection member 73e of the protection member 73. Thus, movement of the coil 53 in the radial direction (direction A2) of the reactor 6 even when the reactor 6 is energized can be prevented.
Further, as can be understood from
Referring again to
In the first embodiment, the abutment members 71c to 73c of the protection members 71 to 73 abut each other, whereby the protection members 71 to 73 are pressed radially outwardly. As a result, since the coils 51 to 53 are pressed between the connection members 71e to 73e of the protection members 71 to 73 and the inner surfaces of the outer peripheral iron core portions 24 to 26, the coils 51 to 53 can be further firmly fastened.
As can be understood from the drawing, the outer peripheral iron core 20 is composed of four outer peripheral iron core portions 24 to 27 divided in the circumferential direction. 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 outer peripheral iron core portions 24 to 27, respectively.
Note that the number of iron cores 41 to 44 and the number of iron core portions 24 to 27 need not necessarily be the same. The same is true for the core body 5 shown in
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
Further,
According to the first aspect, there is provided a reactor (6) comprising a core body (5), the core body comprising an outer peripheral iron core (20), at least three iron cores (41 to 44) arranged in contact with or coupled to an inner surface of the outer peripheral iron core, and at least three coils (51 to 54) wound onto the at least three iron cores, wherein 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 a protection part (70) which at least partially protects projection portions (51a to 54a) of the at least three coils which project from at least one end surface of the core body.
According to the second aspect, in the first aspect, the protection part includes at least three protection members (71 to 74) which protect the respective projection portions of the at least three coils.
According to the third aspect, in the second aspect, the at least three protection members respectively include cover members (71a to 74a), which at least partially cover the projection portions, and insertion members (71b to 74b), which are inserted between the projecting portions and the at least one end surface.
According to the fourth aspect, in the second or third aspect, the at least three protection members include abutment members (71c to 74c) which abut each other at the center of the reactor.
According to the fifth aspect, in any of the first through fourth aspects, the reactor comprises a terminal block (65) and a pedestal (60) which are coupled to the core body so as to interpose the core body therebetween, wherein the protection part is arranged at least one of a region between the terminal block (65) and the core body and a region between the core body and the pedestal.
According to the sixth aspect, in any of the first through fifth aspects, the protection part is formed from a non-magnetic material.
According to the seventh aspect, in any of the first through sixth aspects, the number of the at least three iron cores 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 cores is an even number not less than four.
In the first aspect, since the projection portions of the coils are protected by the protection part, damage to the coils can be prevented.
In the second aspect, the at least three coils can be individually protected.
In the third aspect, since the projection portions of the coils are interposed by cover members and insertion members, vibration of the coils in the axial direction of the reactor when the reactor is energized can be prevented.
In the fourth aspect, since the abutment members of the projection members abut each other, vibration of the coils in the radial direction of the reactor when the reactor is energized can be prevented.
In the fifth aspect, when projection parts are arranged both between the terminal block and the core body and between the core body and the pedestal, both ends of the coils in the axial directions of the reactor can be protected.
In the sixth aspect, the magnetic field can be prevented from passing through the protection part.
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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2017-144705 | Jul 2017 | JP | national |