JP2010177439A - Inductor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small inductor wherein a winding can be cooled efficiently. <P>SOLUTION: An inductor includes a cooling plate that is in contact with the outer peripheral surface of the winding and is an integral part of a core, and an energizing means that is sandwiched between the inner peripheral surface of the winding and the outer peripheral surface of the core and energizes the winding toward the cooling plate. Preferably, by having a part of the energizing means is sandwiched in between the core and the cooling plate, the energizing means is fixed to the core and the cooling plate. Preferably, the energizing means is a flat spring formed by bending a metal plate. More preferably, the metal plate includes its metal plate body and tongue portions formed by making U-shaped cutouts on the metal plate body, and the flat spring is formed by bending the tongue portions against the metal plate body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an inductor used in an electric circuit, and more particularly to an inductor in which a core is disposed in a hollow portion of a cylindrical winding.

  In an electric circuit, an inductor such as that shown in Patent Document 1 is used to boost a voltage. A perspective view of an example of an inductor is shown in FIG.

  As shown in FIG. 1, the inductor 101 is one in which the legs of the core 120 are inserted into the hollow portion of the winding 110 formed in a cylindrical shape, and both are integrally fixed with an adhesive or the like. In addition, a mounting bracket 130 for mounting the inductor 101 in the electrical device is fixed to the core 120.

  When a voltage is applied to the winding 110 of the inductor 101, the winding 110 generates heat due to the current flowing through the winding. Since the inner peripheral surface of the winding 110 is in close contact with the core 120, the heat generated in the winding 110 moves to the core 120 and is naturally radiated from the surface of the core 120.

JP 2004-319679 A

  In the conventional inductor, the winding is cooled by natural heat dissipation as described above. In order to sufficiently cool the winding by natural heat dissipation, it is necessary to increase the heat dissipation area. That is, it is necessary to enlarge the core and increase the surface area of the core 120. As described above, when the core is enlarged, there is a problem that the whole inductor becomes large.

  The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a small inductor capable of efficiently cooling a winding.

  In order to achieve the above object, the inductor of the present invention is sandwiched between a cooling plate that is in contact with the outer peripheral surface of the winding and integrated with the core, and the inner peripheral surface of the winding and the outer peripheral surface of the core. Biasing means for biasing the winding toward the cooling plate.

  In the inductor of the present invention, as described above, since the cooling plate is in contact with the winding, the heat generated in the winding can be released to the cooling plate. And the heat which moved to the cooling plate is removed by forcibly cooling the cooling plate with a fan or the like. In the inductor of the present invention, the winding is pressed against the cooling plate by the urging means, so that heat generated in the winding is efficiently transferred to the cooling plate, and the winding is efficiently cooled. Furthermore, since the biasing means of the inductor of the present invention is arranged between the inner peripheral surface of the winding and the outer peripheral surface of the core, that is, in the cavity of the winding, the volume of the entire inductor is increased. In addition, the cooling efficiency of the winding can be increased.

  Preferably, the urging means is fixed to the core and the cooling plate by sandwiching a part of the urging means between the core and the cooling plate. Preferably, the biasing means is a leaf spring formed by bending a metal plate. More preferably, the metal plate has a metal plate main body and a tongue formed by cutting the metal plate main body into a U-shape, and the plate is formed by bending the tongue with respect to the metal plate main body. A spring is formed. It is good also as a structure which a metal plate main body contact | abuts to the said core, and the front-end | tip of a tongue part contacts the inner peripheral surface of the said coil | winding. In this case, the pair of tongues are arranged side by side in the axial direction of the winding, and the pair of tongues are provided such that each of the tips thereof faces the outside in the axial direction of the winding. It is preferable to do. With such a configuration, the distance between the tips of the pair of tongue portions can be increased, and the winding is stably held by the biasing member.

It is a perspective view of the conventional inductor. It is a perspective view of the reactor of embodiment of this invention. It is a perspective view of the core of the reactor of embodiment of this invention. It is a perspective view of the flat plate and leaf | plate spring of the reactor of embodiment of this invention. In embodiment of this invention, it is an exploded view which shows the attachment procedure to the coil | winding of a core. In embodiment of this invention, it is an exploded view which shows the attachment procedure to the cooling plate of a core and a coil | winding. It is sectional drawing which cut | disconnected the reactor of embodiment of this invention by the plane perpendicular | vertical to the width direction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a perspective view of the inductor (three-phase reactor) according to the embodiment of the present invention. The reactor 1 according to the present embodiment has three sets of windings 11 to 13 arranged around a core 20.

  Details of the core 20 will be described. FIG. 3 is a perspective view of the core 20 of the three-phase reactor 1 of the present embodiment. As shown in FIG. 3, the core 20 includes five blocks 21a, 21b, and 22a to 22c. Each block is a rod-shaped member having a rectangular cross section. The blocks 21a and 21b are arranged side by side in a direction perpendicular to the major axis so that the major axes are substantially parallel to each other. The other three blocks 22a, 22b and 22c are arranged side by side in the major axis direction of the blocks 21a and 21b so that the major axis direction is perpendicular to the major axis direction of the blocks 21a and 21b. Since the blocks are arranged in this way, the core 20 has a “day” shape as a whole. The blocks 21a and 21b are formed with through holes 21c through which the bolts 43 (FIG. 2) are passed.

  The blocks 21a, 21b, 22a-c of the core 20 are formed by laminating a large number of thin sheets of silicon steel, and eddy currents are less likely to occur even when a large current is passed through the windings 11-13. ing. Further, non-magnetic plates 23a and 23b made of a non-magnetic material such as an epoxy / glass mat laminate are sandwiched between the blocks 21a and 21b and the blocks 22a to 22c. The non-magnetic plates 23a and 23b form a gap of the core 20. The blocks 21a, 21b, and 22a to c of the core 20 are not limited to the above-described laminated core, and other types such as a dust core formed by compression molding a ferromagnetic powder such as iron or ferrite. A block of the form may be used.

  The first, second, and third windings 11, 12, and 13 have a cylindrical shape, and the blocks 22a, 22b, and 22c of the core 20 are inserted into the hollow portions, respectively. Both ends of the conductors of the windings 11, 12 and 13 are connected to terminal pairs 31, 32 and 33 (FIG. 2), and the reactor 1 is connected to other electric circuits via the terminal pairs 31, 32 and 33. Connected.

  As described above, in the reactor 1 of the present embodiment, the windings 11 to 13 are inserted into the blocks 22 a to c of the “day” -shaped core 20, and the axes of the windings 11 to 13 are substantially parallel to each other. Are arranged side by side. In the following description, the direction in which the windings 11 to 13 are arranged is the width direction (direction from the upper right to the lower left in FIG. 2), and the axial direction of the windings 11 to 13 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).

  Each of the windings 11 to 13 is disposed such that the outer peripheral surface thereof is in contact with the heat radiating plate 40. The heat sink 40 is disposed on the lower side of the windings 11 to 13 in FIG. Hereinafter, the heat sink 40 side of the reactor 1 is the lower side, and the opposite side (the upper side in FIG. 2) is the upper side. The windings 11 to 13 are held on the heat dissipation plate 40 by fixing the core 20 passed through the windings 11 to 13 to the heat dissipation plate 40 with bolts 43.

  In addition, a pair of stays 44 for fixing the reactor 1 to an electric circuit or the like are attached by bolts 43 on both sides in the depth direction of the upper surface of the core 20.

  Next, a procedure for attaching the windings 11 to 13 to the core 20 will be described. As shown in FIG. 3, the core 20 is formed by combining a plurality of blocks 21a, 21b, and 22a-c. When assembling the reactor 1, in order to maintain the mutual arrangement of the combined blocks, the upper and lower surfaces of the core 20 are sandwiched between a flat plate 41 and a leaf spring 42 (FIG. 2), respectively.

  4A and 4B are perspective views of the flat plate 41 and the leaf spring 42, respectively. As shown in FIG. 4, the flat plate 41 is a plate having a base portion 41 a and three end portions 41 b extending from both ends and the center of the base portion 41 a and having an E shape as a whole. A hole 41c through which the bolt 43 is passed is formed in the base 41a.

  Further, the leaf spring 42 is a plate having a base portion 42a and three end portions 42b extending from both ends and the center of the base portion 42a. The base portion 42a is formed with a hole 42c through which the bolt 43 is passed. A tongue portion 42d is formed at approximately the center of each of the end portions 42b of the leaf spring 42 by forming a notch 42e in a U-shape at the end portion 42b. The tongue portion 42d is bent downward in the height direction.

  Next, the procedure for assembling the reactor 1 will be described. The reactor 1 is first assembled from main parts (portions composed of the windings 11 to 13, the core 20, the nonmagnetic plates 23 a and 23 b, the flat plate 41, and the leaf spring 42). FIG. 5 is an exploded view of the main part of the reactor 1. First, as shown in FIG. 5, the combined blocks 21 b, 22 a to 22 c and the nonmagnetic plate 23 b are sandwiched between the flat plate 41 and the plate spring 42 from above and below. Next, the blocks 22a to 22c are inserted into the hollow portions of the windings 11 to 13, respectively. At this time, the end 41b of the flat plate 41 and the end 42b of the leaf spring 42 pass through the cavities of the windings 11 to 13 together with the blocks 22a to 22c, respectively, and protrude from the opposite side (upper left in FIG. 5). By attaching the block 21a and the non-magnetic plate 23a to the space between the flat plate 41 and the protruding portion of the leaf spring 42, the windings 11 to 13 are attached to the blocks 22a to 22c. The core 20 is assembled.

  Next, a procedure for fixing the core 20 to the heat sink 40 will be described. FIG. 6 is an exploded view of the entire reactor 1. As shown in FIG. 6, the pair of stays 44 and the heat radiating plate 40 are formed with through holes 44 a and 40 a for allowing the bolts 43 to pass therethrough. The core 20 and the windings 11 to 13 are placed on the heat radiating plate 40, the stay 44 is placed on the flat plate 41, and the bolt 43 is mounted on the through hole 44a of the stay 44, the hole 41c of the flat plate 41, the through hole 21c of the core 20, and the plate The core 20, the flat plate 41, the plate spring 42 and the stay 44 are inserted into a hole 42 c (not shown) of the spring 42 and a through hole 40 a of the heat sink, and a nut (not shown) is screwed into the bolt 43 from below the heat sink 40. It is fixed to the heat sink 40 and these are integrated. At this time, the flat plate 41 and the plate spring 42 are in close contact with the core 20, and the blocks 22a to 22c and the nonmagnetic plates 23a and 23b are held between the flat plate 41 and the plate spring 42, and the blocks 21a, 21b, and 22a to 22c. The non-magnetic plates 23a and 23b are integrated.

  In the present embodiment, in order to dissipate heat generated when a current is passed through the winding, the windings 11 to 13 are brought into contact with the heat dissipation plate 40 disposed thereunder.

  Next, the structure which makes a coil | winding contact the heat sink 40 is demonstrated. FIG. 7 is a cross-sectional view of the reactor 1 taken along a plane that includes the axis of the winding 11 and is perpendicular to the heat sink 40. As shown in FIG. 7, the lower portion 11 a of the inner peripheral surface of the winding 11 is in contact with the tongue 42 d of the leaf spring 42. As described above, the leaf spring 42 is sandwiched and fixed between the core 20 (blocks 21a and 21b) and the heat radiating plate 40. For this reason, the tongue portion 42 d is elastically deformed in a direction approaching the end portion 42 b of the leaf spring 42, and the winding 11 is pressed toward the heat radiating plate 40 by the repulsive force. Further, the other windings 12 and 13 are also pressed against the heat radiating plate 40 by the tongue portion 42 d of the leaf spring 42.

  As described above, in the present embodiment, since the cooling air is applied to the heat radiating plate 40 and the heat radiating plate 40 is forcibly cooled, the temperature of the cooling plate 40 is kept relatively low. Then, the windings 11 to 13 are pressed against the heat radiating plate 40 by the leaf spring 42, so that the outer peripheral surface of each winding is in close contact with the heat radiating plate 40, and the heat generated in the windings 11 to 13 is efficiently transferred to the heat radiating plate 40. Moving. Therefore, according to the present embodiment, the windings 11 to 13 can be efficiently cooled. Further, as described above, the leaf spring 42 for pressing the windings 11 to 13 against the cooling plate 40 is sandwiched between the core 20 and the inner peripheral surface of the hollow portion of the winding. Thus, a reactor in which the winding is cooled with high efficiency is realized.

  As shown in FIGS. 4 and 7, the pair of tongue portions 42 d provided at the end portions 42 b of the leaf springs 42 are arranged side by side in the depth direction of the reactor 1. It is formed to face outward in the depth direction. For this reason, the space | interval of the front-end | tips of the tongue part 42d can be taken long compared with the structure which the front-end | tip of a pair of tongue part 42d faces a depth direction inner side. When the interval between the tips of the tongue portion 42, that is, the interval between the contact portions between the tongue portion 42d and the winding is relatively short, the holding of the winding by the tongue portion 42d becomes unstable. As described above, since the interval between the contact portions is long, the winding is stably held.

  Although the inductor of the embodiment of the present invention described above is a three-phase reactor, the present invention is not limited to this configuration. For example, in the case of inductors of other shapes such as a single-phase reactor in which two sets of windings are provided on a cooling plate or an inductor having only one set of windings, the outer peripheral surface of the core and the inner peripheral surface of the windings By sandwiching an urging member such as a leaf spring between the windings so that the windings are pressed against the cooling plate, a small inductor capable of efficiently cooling the windings can be formed.

DESCRIPTION OF SYMBOLS 1 Reactor 11, 12, 13 Winding 20 Core 40 Cooling plate 41 Flat plate 42 Leaf spring 42a Base part 42b End part 42d Tongue part 42e Notch

Claims (7)

An inductor in which at least a part of a core is disposed in a hollow portion of a cylindrical winding,
A cooling plate in contact with the outer peripheral surface of the winding and integral with the core;
And a biasing means sandwiched between the inner peripheral surface of the winding and at least a part of the outer peripheral surface of the core, and biasing the winding toward the cooling plate.   2. The inductor according to claim 1, wherein a part of the urging means is sandwiched between the core and the cooling plate, whereby the urging means is fixed to the core and the cooling plate. .   The inductor according to claim 1 or 2, wherein the biasing means is a leaf spring formed by bending a metal plate. The metal plate has a metal plate main body and a tongue formed by cutting the metal plate main body into a U-shape;
The inductor according to claim 3, wherein the leaf spring is formed by bending the tongue portion with respect to the metal plate main body. The metal plate body is in contact with the core;
5. The inductor according to claim 4, wherein a tip of the tongue is in contact with an inner peripheral surface of the winding.   The inductor according to claim 4 or 5, wherein the metal plate has a pair of tongue portions arranged side by side in the axial direction of the winding.   The inductor according to claim 6, wherein each of the pair of tongue portions is provided such that each of the tips thereof faces the outside in the axial direction of the winding.

Images