JP4717904B2 - Reactor - Google Patents

Description

  The present invention relates to a reactor that is a coil in which a plurality of sets of windings are provided on one core.

A reactor is a coil in which multiple windings (two sets for a single-phase reactor and three sets for a three-phase reactor) are provided on one core. For example, power factor improvement in inverter equipment, suppression of harmonic current, etc. Used for. FIG. 1 shows a perspective view of an example of a conventional three-phase reactor for large current. Since a relatively large current flows through the windings 113a, 113b, and 113c of the reactor 101, the amount of generated heat is large. As a structure for dissipating heat from the winding, for example, as in Patent Document 1, a configuration in which the winding is brought into contact with a metal heat dissipation plate is used. In the conventional reactor 101, as shown in FIG. 1, by placing the winding on the heat radiating plate 121, heat generated in the coil escapes to the heat radiating plate by thermal contact.
JP 2001-144478 A

  As described above, in the conventional reactor, since the winding is merely in contact with the heat sink, the contact area and the contact pressure between the winding and the heat sink are small, and the heat from the winding to the heat sink is reduced. The efficiency of movement was poor. In addition, the contact area and the contact pressure between the winding and the heat radiating plate may vary, and the efficiency of heat transfer to the heat radiating plate may be different for each winding. Thereby, since the heat radiation efficiency differs for each winding, there is a possibility that the temperature difference becomes a size that cannot be ignored.

  The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a reactor that can efficiently move the heat of a winding to a heat sink.

In order to achieve the above object, the reactor of the present invention includes a biasing unit that biases the plurality of windings toward the heat sink. The urging means is a band that urges the plurality of windings toward the heat radiating plate, for example, by tightening the plurality of windings and the heat radiating plate together.
Moreover, it is preferable to further have an insulating member sandwiched between the upper surfaces of the plurality of windings and the urging means. Furthermore, it further has a core around which a plurality of windings are wound, a part of the core is cut off and filled with a gap material, and the insulating member is preferably a plate having the same material and thickness as the gap material. .
Moreover, it is preferable to further have a spacer plate that is sandwiched between at least a part of the upper surface of at least one of the windings arranged in the center and the biasing means.

  As described above, in the present invention, the plurality of windings are biased toward the heat sink by the biasing means, so that the contact area and the contact pressure between the windings and the heat sink can be increased. Thereby, the heat of a coil | winding can be efficiently moved to a heat sink. Further, by sandwiching a spacer plate between at least a part of the upper surface of at least one of the windings arranged in the center and the biasing means, the contact area between the winding and the heat sink By adjusting the contact pressure, it is possible to reduce variations in contact area and contact pressure between the winding and the heat sink. This configuration is particularly effective for a three-phase reactor having three windings.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 2 is a perspective view of the three-phase reactor according to the first embodiment of the present invention. The reactor 1 of the present embodiment includes a coil 10 formed by winding three sets of windings 13 a to 13 c around a core 11. Moreover, the width | variety of the reactor 1 of this embodiment, the depth, and the dimension of a height direction are the magnitude | sizes of about 100-200 mm, respectively.

  In the following description, the direction in which the windings 13a to 13c are arranged is the width direction (the direction from the upper right to the lower left in FIG. 2), and the axial direction of the windings 13a to 13c is the depth direction (from the upper left in FIG. 2). The direction perpendicular to both the width direction and the depth direction is the height direction (the direction from bottom to top in FIG. 2).

  Details of the coil 10 will be described below. FIG. 3 is an upper surface of the coil 10 of the three-phase reactor 1 of the present embodiment. As shown in FIG. 3, the core 11 of the coil 10 has rod-shaped blocks 11a and 11b having a rectangular cross section arranged along the width direction so that the major axes thereof are parallel to each other, and the block 11a. 11b, rod-like blocks 11c, 11d, and 11e having a rectangular cross section are arranged so as to be orthogonal to the blocks 11a and 11b to form a “day” -shaped core as a whole.

  The blocks 11a to 11e of the core 11 are each formed by laminating a large number of thin sheets of silicon steel, and eddy currents are hardly generated even when a large current is passed through the windings. Further, between the blocks 11a and 11b and the blocks 11c to 11e, nonmagnetic plates 11f and 11g having a thickness of about 1 mm formed from a nonmagnetic material such as an epoxy / glass mat laminate are sandwiched. The non-magnetic plates 11f and 11g form a gap of the core 11.

  The first, second and third windings 13a, 13b and 13c of the coil 10 are wound around blocks 11c, 11d and 11e, respectively. Both ends of the windings 13a, 13b, and 13c are connected to terminal pairs 22a, 22b, and 22c, respectively (FIG. 2), and the reactor 1 is connected to other electric circuits through the terminal pairs 22a, 22b, and 22c. To do.

  In the present embodiment, the windings 13 a, 13 b, and 13 c are brought into contact with the heat radiating plate 21 in order to dissipate heat generated when a current is passed through the windings. A structure in which the windings 13a, 13b, and 13c are brought into contact with the heat sink 21 will be described below.

  A pair of spacer blocks 26 are fixed to both ends of the heat sink 21 in the depth direction. In addition, two notches 26 a are formed on the lower surface of the spacer block 26. The blocks 11a and 11b of the core 11 are fixed to the heat radiating plate 21 through the spacer block 26 by nuts 27 (described in FIG. 4) and screws 24 arranged in the notch 26a. Since the height of the spacer block 26 is slightly larger than the winding thickness (distance from the inner circumference to the outer circumference of each winding) of the windings 13a, 13b, and 13c, the windings 13a, 13b, and 13c are the blocks 11c, 11d and 11e and the heat radiating plate 21 are accommodated without difficulty.

  A stay 25 for fixing the core 11 to the spacer block 26 is fixed on the blocks 11 a and 11 b of the core 11.

  In the present embodiment, each winding 13a, 13b, 13c is brought into contact with the heat radiating plate 21 reliably and evenly, and the amount of heat transferred from each winding to the heat radiating plate 21 is made substantially equal to each other by the band 30. The heat sink 21 is biased. Hereinafter, with reference to FIG. 2 and FIG. 4, a structure for energizing the winding by the band 30 will be described.

  FIG. 4 is a side view of the reactor 1 according to the present embodiment projected in the depth direction. In FIG. 4, the stay 25 and the terminals 22a to 22c are omitted in order to show the coil 10 and the band 30 more clearly.

  The heat sink 21 is a plate made of a metal having a high thermal conductivity such as copper or aluminum. Further, a heat radiating sheet 21b having a thickness of about 0.5 mm is provided on the upper surface of the heat radiating plate 21. The heat dissipation sheet 21b is a sheet having high thermal conductivity and electrical insulation. Each of the windings 13a, 13b, and 13c comes into contact with the heat dissipation plate 21 through the heat dissipation sheet 21b, and the metal portion of the heat dissipation plate 21 and the winding are not in direct contact with each other.

  Further, at both ends in the width direction of the heat radiating plate 21, bent portions 21 a that are bent substantially vertically toward the upper side are formed. The band 30 is fixed to the bent portion 21a.

  As shown in FIG. 4, the band 30 of this embodiment is formed by connecting the first and second belts 31 and 32 with screws 33. The first and second belts 31 and 32 are stainless steel strips each having a thickness of about 0.3 mm and a width of about 30 mm. The first and second belts 31 and 32 have a heat radiating plate at one end thereof (the first belt 31 has a lower left side in FIG. 4 and the second belt 32 has a lower right side in FIG. 4) by a rivet 21c. 21 is fixed to the bent portion 21a.

  First and second bars 34 disposed along the width direction of each belt (the depth direction of the reactor 1) on the other end side (the center upper portion in FIG. 4) of the first and second belts 31 and 32. , 35 are fixed. The first and second bars 34 and 35 have a cylindrical shape. The first bar 34 is formed with a female thread 34a along its radial direction (left and right direction in FIG. 4, the width direction of the reactor). The second bar 35 is formed with a through hole 35a along the radial direction (the width direction of the reactor). The first belt 31 and the second belt 32 are connected by passing the screw 33 through the through hole 35 a of the second bar 35 and then screwing the screw 33 into the female screw 34 a of the first bar 34. The tension of the first and second belts 31 and 32 is adjusted by adjusting the tightening torque of the screw 33.

  As shown in FIG. 2, the other end sides of the first and second belts 31 and 32 are folded back toward one end side, and the bars 34 and 35 are arranged at the folded portions. Yes. And the notch 31a and 32a for letting the screw 33 pass are provided in the return part of the 1st and 2nd belts 31 and 32 so that the screw 33 can be attached from the outside of the band 30.

  In the present embodiment, the insulating plate 41 is sandwiched between the upper surface of each winding and the belt so that the windings 13a, 13b, and 13c do not directly contact the metal first and second belts 31 and 32. ing. The insulating plate 41 is the same plate as the nonmagnetic plates 11f and 11g. For this reason, since it is not necessary to design and manufacture the insulation plate 41 separately, the cost of a reactor can be reduced. As described above, since the purpose of using the insulating plate 41 is to prevent contact between the belt and the winding, a plate having a material and a size different from those of the nonmagnetic plates 11f and 11g is used as the insulating plate 41. May be.

  As shown in FIG. 4, a spacer plate 42 is sandwiched between the upper surface of the second winding 13 b disposed at the center in the width direction of the reactor 1 and the insulating plate 41. The spacer plate 42 is a plate that is thicker (for example, 3 mm) than the insulating plate 41. As shown in FIG. 4, the spacer plate 42 is disposed only on the central winding 13b. In the absence of the spacer plate 42, the urging force that presses the coil 10 against the heat radiating plate 21 due to the tension of the belts 31 and 32 is the largest at both ends in the width direction of the band 30, that is, the central portion of the band 30, that is, the second winding. It becomes the smallest at the position of 13b. For this reason, in the winding 13b, the thermal contact with the heat radiating plate 21 through the heat radiating sheet 21b is less than that of the other windings 13a and 13c, and the contact becomes unstable and heat is easily stored. For this reason, in this embodiment, by inserting the spacer plate 42 between the second winding 13b and the insulating plate 41, the magnitude of the force that urges the first and third windings 13a and 13c is increased. The magnitude of the force for energizing the second winding 13b is made substantially equal.

  As described above, in the present embodiment, the windings 13a, 13b, and 13c are urged toward the heat radiating plate 21 by the band 30, so that the winding and the heat radiating plate are reliably heated via the heat radiating sheet 21b. Therefore, more heat can be transferred from each winding to the heat sink 21. Further, since the substantially uniform biasing force is applied to each winding by the spacer plate 42, the efficiency of heat transfer from each winding to the heat radiating plate 21 becomes substantially equal. For this reason, the temperature difference between windings becomes small, and as a result, the resistance and inductance of each winding become substantially equal.

  In the first embodiment of the present invention described above, the spacer plate 42 is disposed on the winding 13b on the center side in the width direction to increase the force with which the band 30 biases the winding 13b. . However, the present invention is not limited to the above configuration, and the windings 13a, 13b, and 13c are used as the heat sink 21 as in the reactors according to the second and third embodiments of the present invention described below. Another configuration may be employed in which the force for urging the force is equal.

  FIG. 5 shows a front view of a reactor 1 ′ according to the second embodiment of the present invention. Similar to FIG. 4, in FIG. 5, the stay 25 and the terminals 22 a to 22 c are omitted in order to more clearly show the coil 10 and the band 30. As shown in FIG. 5, the reactor 1 ′ of this embodiment is formed by winding a spacer plate 42 ′ having a sufficiently large thickness in place of the spacer plate 42 (FIG. 4) in the reactor 1 of the first embodiment. The wires 13a, 13b, and 13c are arranged over the entire upper surface. Since the spacer plate 42 'has a large plate thickness, it has a rigidity that hardly bends even when a load due to the tension of the band 30 is applied, and the load applied from the band 30 is distributed substantially evenly to each winding. Can do. When such a spacer plate is used, the spacer plate 42 ′ may be sandwiched between the band 30 and the insulating plate 41 as shown in FIG.

  FIG. 6 is a side view of a reactor 1 ″ according to the third embodiment of the present invention. As shown in FIG. 6, the reactor 1 ″ of this embodiment has a cross-section projected in the width direction in an Ω shape instead of the spacer plate 42 ′ (FIG. 5) of the second embodiment. A spacer plate 42 '' may be used. This spacer plate 42 '' is a kind of leaf spring and elastically deforms relatively easily in the height direction of the reactor 1, that is, in the direction in which the band 30 biases the windings 13a, 13b, 13c. It is like that. On the other hand, in the width direction of the reactor 1, the Ω-shaped cross section serves as a kind of rib, so that the spacer plate 42 ″ has high bending rigidity. For this reason, the spacer plate 42 '' of the reactor 1 '' according to the present embodiment can disperse the load applied from the band 30 substantially evenly in each winding, like the spacer plate 42 'of the second embodiment. .

  The reactors 1, 1 'and 1 "according to the first, second and third embodiments of the present invention described above are three-phase reactors using three sets of windings. However, the present invention is not limited to the above configuration, and can be applied to a single-phase reactor using two sets of windings. An example of such a single-phase reactor is shown in a fourth embodiment of the present invention described below.

  FIG. 7 shows a perspective view of a single-phase reactor 1 ″ ″ according to the fourth embodiment of the present invention. As in the first embodiment of the present invention, the reactor 1 ′ ″ has a relatively small longitudinal direction (that is, the widthwise dimension of the reactor 1 ′ ″) between the insulating plate 41 and the windings 13d and 13e. The spacer plate 42 is sandwiched. In the reactor 1 according to the first embodiment of the present invention, since there are three sets of windings, a spacer plate is disposed on the central winding 13b. On the other hand, since the single-phase reactor 1 ′ ″ in FIG. 7 has two sets of windings, the spacer plate 42 is disposed across the first winding 13d and the second winding 13e. .

  In the single-phase reactor 1 ′ ″, the spacer plate 42 ′ of the second embodiment and the spacer plate 42 ″ of the third embodiment can be used instead of the spacer plate 42. Needless to say.

  Further, the present invention is not limited to the configuration of the above embodiment, and can be appropriately modified according to the shape and characteristics of the reactor. For example, instead of the band 30 used in the above-described embodiment, a configuration in which the winding is urged toward the heat radiating plate by pushing the spacer plate toward the winding with a coil spring, a leaf spring, or a screw or the like. Good.

It is a perspective view of the conventional three-phase reactor. 1 is a perspective view of a three-phase reactor according to a first embodiment of the present invention. It is a top view of the coil of the three-phase reactor by the 1st Embodiment of this invention. It is a front view of the three-phase reactor by the 1st Embodiment of this invention. It is a front view of the three-phase reactor by the 2nd Embodiment of this invention. It is a side view of the three-phase reactor by the 3rd Embodiment of this invention. It is a perspective view of the single phase reactor by the 4th Embodiment of this invention.

Explanation of symbols

1, 1 ′, 1 ″ three-phase reactor 1 ′ ″ single-phase reactor 10 coil 11 core 13a first winding 13b second winding 13c third winding 13d first winding 13e second Winding 21 Heat radiation plate 21b Heat radiation sheet 26 Spacer block 30 Band 31 First belt 32 Second belt 33 Screw 34 First bar 35 Second bar 41 Insulating plate 42, 42 ', 42''Spacer plate

Claims (7)

A heat sink,
A plurality of windings arranged on the heat sink;
Biasing means for biasing the plurality of windings toward the heat sink;
A reactor having a,
Said biasing means, Ri Oh a plurality of windings by tightening the said heat radiating plate and the plurality of windings together with a band for urging the heat radiating plate,
The band spans from one end of the heat sink to the other end along the arrangement direction of the plurality of windings ,
A spacer plate is further interposed between at least a part of the upper surface of at least one of the windings arranged in the center and the biasing means.
A reactor characterized by that. Two windings,
The spacer plate is sandwiched between the upper surfaces of the two windings and the biasing means.
The reactor according to claim 1. Reactor according to claim 1 or 2 wherein the biasing means, characterized in that adjustable load that urges the plurality of windings. The reactor according to any one of claims 1 to 3 , further comprising an insulating member sandwiched between upper surfaces of the plurality of windings and the urging means. A core on which the plurality of windings are wound;
A portion of the core is severed and filled with a gap material;
The reactor according to claim 4 , wherein the insulating member is a plate having the same material and thickness as the gap material. The reactor according to claim 1 , wherein the spacer plate has a bending rigidity that does not substantially deform by an urging force from the urging means. The spacer plate is elastically deformable with respect to a height direction of the spacer plate, and has a high bending rigidity with respect to a moment around an axis orthogonal to the arrangement direction of the plurality of windings and the height direction. The reactor according to claim 1 .

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