JP2012069751A - Reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor achieving a small size without reducing an inductance value.SOLUTION: A reactor 10 includes a core formed by joining a first core 1 and a second core 2 both made of magnetic material, and a coil 3 having an insulating film and being wound around a magnetic leg of the core, and is configured so that at least portions of the coil 3 corresponding to top and bottom ends of the magnetic leg around which the coil 3 is wound are insulation-coated with the insulator 3a. By this configuration, an insulation distance between the coil 3 and the EI-type core can be secured at a larger distance than that of a configuration where an insulating member is arranged around a periphery of a middle leg 1b forming a magnetic leg of an E-type core 1. Therefore, the distance between the coil 3 and the EI-type core outer surface can be made shorter than a creepage distance required in a safety standard, thereby contributing to the downsizing of the reactor 10.

Description

  The present invention relates to a reactor, and more particularly to a configuration in which an insulation distance between a wound coil and a core is ensured so as to reduce the size.

  Conventionally, in a reactor using an EI type core, an EE type core, or the like, for example, an electromagnetic steel plate such as a silicon steel plate having a relatively low price and good magnetic properties is replaced with a predetermined shape such as an E type or an I type. After punching out, a core is formed by stacking a plurality of sheets into blocks and combining them. The laminated electromagnetic steel plates are blocked by a method of bonding the electromagnetic steel plates using an adhesive, a method using riveting or caulking, or a method of welding the electromagnetic steel plates.

  With the above-described configuration, an EI type core in which electromagnetic steel plates are laminated is used. For example, as shown in a reactor 300 shown in FIGS. An E-type core 304 comprising a leg 302 and a connecting portion 303 for connecting them; and an I-type core 305 joined to the distal ends of the middle leg 301 and the outer leg 302 of the E-type core 304, The middle leg 301 of the E-shaped core 304 includes a coil 307 made of a conductor wound around the outer periphery with an insulating paper 306 so that a creepage distance or a spatial distance required by safety standards can be secured. It is generally known that the E-shaped core 304 and the inner surface of the coil 307 are separated from each other by a predetermined spatial distance A, and an insulating paper 308 is provided between the coil 307 and the outer leg 302.

  In assembling the reactor 300, when the coil 307 is wound around the middle leg 301 of the E-shaped core 304 as described above, the insulating paper 306 provided between the middle leg 301 and the coil 307 and the insulating paper 306 are provided. For this reason, there is a problem that an assembly man-hour is required. Further, the lower ends 301d and the upper ends 301e of the middle leg 301 shown in FIG. 4A and FIG. 4B cannot be insulated by the insulating paper 306. Therefore, the lower ends 301d and the inner diameter lower corners 307c of the coil 307 corresponding to the lower ends 301d. In addition, as shown in FIG. 4B, the E-type core 304 and the coil 307 are insulated from each other and between the upper ends 301e and the corresponding inner diameter upper corners 307d of the coil 307. Therefore, there is a problem in that the outer shape of the wound coil 307 is increased and the reactor 300 cannot be reduced in size.

  In order to reduce the size of the reactor 300, it is necessary to make the outer shape of the coil 307 larger by reducing the spatial distance A described above. Therefore, for example, like a reactor 100 shown in FIG. 5, an E-type core 104 composed of a middle leg 101 and an outer leg that form magnetic legs, and a connecting portion that connects them, and the E-type core 104 are joined. And a coil 106 wound around the middle leg 101 with insulating paper 105 interposed therebetween, and a lower notch groove 108 is formed on the connecting portion 103 side in the outer peripheral portion of the middle leg 101. On the other hand, it is known that an upper notch groove 109 is formed at an opposing position of an I-type core 105 facing the lower notch groove 108 so that a coil 106 is wound around the middle leg 101 (for example, Patent Document 1).

  The reactor 100 described in Patent Document 1 is formed with a lower notch groove 108 and an upper notch groove 109, so that both upper and lower ends of the middle leg 101 are compared to the reactor 300 shown in FIGS. 4 (A) and 4 (B). And the distance between the upper and lower corners of the inner diameter of the coil 106 increases. Since this distance is increased, the E-type core 104 and the coil 106 can be insulated even if the spatial distance is narrowed. Therefore, the outer dimension of the coil 106 can be reduced and the reactor 100 can be downsized. I am trying to figure it out.

  However, in the reactor 100 described above, the lower notch groove 108 and the upper notch groove 109 are formed, so that the cross-sectional area of the core 104 is reduced, and the magnetic flux density in this portion is increased, causing partial magnetic saturation. To do. Thereby, an inductance value fell and there existed a possibility that the performance of the reactor 100 might deteriorate.

  Further, as in a reactor 200 shown in FIG. 6, for example, an E-type core 204 including a middle leg 201 and an outer leg that form magnetic legs, and a connecting portion that connects them, and an E-type core 204 are joined. An I-type core, and a coil 206 wound around the middle leg 201 via an insulating paper 205. The coil 206 has a step-shaped inner diameter winding start side 207 with an E-type core. What is wound so that it may become the insertion direction to 204 is known (for example, refer patent document 2).

  The reactor 200 described in Patent Document 2 has a step shape on the inner diameter winding start side 207 of the coil 206, so that the upper and lower portions of the middle leg 201 are higher than the reactor 300 shown in FIGS. 4 (A) and 4 (B). The distance between both ends and the upper and lower corners of the inner diameter of the coil 206 is increased. Since this distance is increased, the E-type core 204 and the coil 206 can be insulated even when the spatial distance is narrowed. Therefore, the outer dimensions of the coil 206 can be kept small, and the reactor 200 can be downsized. I am trying to figure it out.

  However, in the reactor 200 described above, the number of turns of the coil 206 wound around the middle leg 201 is reduced by forming the inner diameter winding start side 207 of the coil 206 in a step shape and shortening the entire winding length. As a result, the desired inductance value may not be obtained.

JP 2002-208525 A JP 2005-158864 A

  In view of the above problems, an object of the present invention is to provide a reactor in which a coil and a core are insulated to achieve a desired performance and can be reduced in size.

  In order to achieve the above-described object, the present invention has the following features.

A core formed by joining a first core and a second core made of a magnetic material, and a coil having an insulating film wound around a magnetic leg of the core;
The coil corresponding to at least the upper and lower end portions of the magnetic leg is covered with an insulating material.

  In addition, the insulator is made of a heat shrinkable tube.

  According to the present invention, when the coil is wound around the magnetic leg of the core, the coil corresponding to the upper and lower parts of the magnetic leg is insulated and coated with the insulator made of the heat shrinkable tube. It is possible to insulate between the coil and the core without forming a notch groove in the core corresponding to the above, or without forming the inner diameter winding start side of the coil in a staircase shape, thereby reducing the size without deteriorating the performance of the reactor. be able to.

  In addition, since the coil and the core are insulated by winding a coil covered with insulation coating around the magnetic leg, the insulating paper between the coil and the magnetic leg around which the coil is wound can be deleted. Workability is improved.

It is an external appearance perspective view of the reactor by this invention. It is explanatory drawing of the reactor by this invention, (A) is a front view, (B) is a top view, (C) is a side view. It is an exploded view of the reactor by this invention. It is explanatory drawing which shows the 1st example of the reactor by a prior art example, (A) is a front view, (B) is a top view. It is a front view which shows the 2nd example of the reactor by a prior art example. It is a front view which shows the 3rd example of the reactor by a prior art example.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. As an example, a reactor used for a power circuit such as an air conditioner and used for power factor improvement will be described as an example. However, the present invention is not limited to the following embodiments, and various modifications can be made without departing from the spirit of the present invention.

  A reactor 10 according to the present invention includes a first core composed of an E-type core 1 and an I-type core 2 as shown in FIG. 1, FIG. 2 (A) to FIG. 2 (C), and FIG. 3. A coil 3 formed by winding a wire 3b in which a predetermined portion is covered with an insulator made of an insulating tube 3a, an EI type core and the coil 3 Insulating paper 4 that is insulated from each other.

  Although not shown, the reactor 10 includes a bottom plate for attaching the reactor 10 to an electrical device, and lead wires, terminals, and terminal blocks for connecting the reactor 10 to a control board of the electrical device. .

  The E-type core 1 is formed of an electromagnetic steel plate such as a silicon steel plate, and as shown in FIGS. 2 (A) to 2 (C), has an E-type shape with a predetermined depth dimension D as seen from the front. The E-shaped core 1 is composed of three magnetic legs including a middle leg 1b provided at the center and outer legs 1a provided on both sides of the E-type core 1. And a connecting portion 1c for connecting the magnetic legs.

  The I-type core 2 is formed of an electromagnetic steel plate such as a silicon steel plate, and as shown in FIGS. 2 (A) to 2 (C), the width dimension L is the same as the E-type core 1, and for example, A plurality of electromagnetic steel plates having a substantially rectangular shape whose height dimension H is the same as the width dimension W of the outer leg 1 a of the E-type core 1 are laminated so as to have the same depth dimension D as that of the E-type core 1. Thus, it has a substantially rectangular parallelepiped shape. The tip of the outer leg 1a of the E-type core 1 is joined to the corresponding surface of the I-type core 2 by welding to form an EI-type core constituting the reactor 10.

  As shown in FIG. 3, the coil 3 is formed by winding a so-called magnet wire, which is a wire 3b in which a polyester insulating coating is provided on a conductive wire such as copper, a predetermined number of times. The periphery is formed so as to be inserted into the middle leg 1 b of the E-shaped core 1. As shown in FIGS. 2A and 3, the wire 3 b which is the first inner circumferential portion of the wound coil 3 is insulated and covered with an insulator made of an insulating tube 3 a. The portion of the wire 3b is insulated from the E-type core 1 and the I-type core 2 by an insulating paper 4 formed in a U-shape.

  The space between the coil 3 and the EI core other than the first layer in the inner peripheral portion is not limited to the configuration insulated by the above-described U-shaped insulating paper 4, but between the coil 3 and the EI core. The insulation tube 3a covered with the wire 3b that forms the outer periphery of the wound coil 3 may be used.

  The inner peripheral layer of the wound coil 3 is insulated from the middle leg 1b of the E-type core 1 by the insulating tube 3a, so that it is necessary to provide insulating paper between the outer circumference of the middle leg 1b. The coil 3 can be inserted into the E-shaped core 1 by providing the U-shaped insulating paper 4 only on the outer periphery thereof.

  Therefore, since the insulating paper can be deleted from between the coil 3 and the middle leg 1b of the E-type core 1, for example, an insulating paper is provided on the outer circumference of the middle leg 1b and the inner circumference of the coil 3 is brought into close contact therewith. Thus, the troublesome work of inserting the coil 3 becomes unnecessary, and the workability when the coil 3 is inserted into the E-type core 1 is improved.

  In addition, the coil 3 has a space 3 between the coil 3 and the EI type core by insulatingly covering the wire 3b, which is a portion facing the outer periphery of the middle leg 1b of the E type core 1, with the insulating tube 3a. Since it becomes possible to insulate even if it narrows, it becomes the structure which can reduce the reactor 10 in size.

  Specifically, in the conventional reactor 300 shown in FIGS. 4A and 4B, the lower ends 301d and the upper ends 301e of the middle leg 301 cannot be insulated by the insulating paper 306. In order to insulate between the inner diameter lower corners 307c of the corresponding coil 307 and between the upper ends 301e and the corresponding inner diameter upper corners 307d of the coil 307, the E-shaped core 304 and the coil 307 A predetermined spatial distance A is required between On the other hand, in the reactor 10 according to the present embodiment, the wire 3b in the inner peripheral portion of the coil 3 is insulated and covered with the insulating tube 3a, so that the lower ends 1d of the middle leg 1b and the inner diameter lower corners 3c of the coil 3 Or the upper both ends 1e and the inner diameter upper both corners 3d of the coil 3 can be insulated by a spatial distance B narrower than the predetermined spatial distance A described above.

  Therefore, the outer diameter of the coil 3 to be wound can be reduced, and the coil 3 and the EI type core can be insulated. As in the background art described above, the EI type core can be insulated. The reactor 10 can be reduced in size without forming the upper and lower cutout grooves or forming the inner diameter winding start side of the coil in a stepped shape to deteriorate the performance of the reactor 10.

  In addition, as a configuration for insulating the coil 3 from the middle leg 1b of the E-type core 1, an insulating paper (not shown) is provided between the coil 3 and the middle leg 1b, and the coil 3 has a lower end 1d of the middle leg 1b. In addition, only the wire 3b serving as a portion corresponding to the upper end portion 1e may be covered with the insulating tube 3a.

  Further, the insulating tube 3a for insulatingly covering the wire 3b is constituted by a heat-shrinkable tube, and thereby, an inner peripheral portion serving as a portion of the coil 3 facing the outer peripheral portion of the middle leg 1b of the E-type core 1 When the heat shrinkable tube is covered on the first layer of wire 3b and insulated by heat treatment, the insulating tube 3a adheres to the wire 3b by heat shrinkage.

  Therefore, for example, by using a heat-shrinkable tube made of a material such as polyolefin or a fluorine-based polymer and having a thickness after shrinkage of about t0.18 to t0.2 millimeters, the diameter of the wire 3b is not excessively increased. Thus, an increase in the space factor of the wire 3b, which is the first layer of the inner peripheral portion of the coil 3 facing the outer peripheral portion of the middle leg 1b, can be minimized.

  Next, based on FIG. 1 thru | or FIG. 3, the assembly method and assembly procedure of the reactor 10 which consists of the structure mentioned above are demonstrated below.

  First, when the coil 3 is inserted into the middle leg 1b of the E-shaped core 1, the wire 3b, which becomes the portion facing the outer periphery thereof, is pre-insulated with an insulating tube 3a made of a heat-shrinkable tube, and then a predetermined number of times. In this way, it is formed into a shape that can be inserted into the E-type core 1 as shown in FIG.

  The wound coil 3 includes a plurality of insulating papers 4 formed in a U shape on the outer periphery thereof, and is inserted into the E-shaped core 1 as indicated by an arrow shown in FIG.

  Next, the corresponding surfaces of the I-type core 2 are assembled and joined to the upper end of the E-type core 1 as shown by the arrows in FIG. As a result, a reactor 10 as shown in FIG. 1 and FIGS. 2 (A) to 2 (C) is formed. Finally, a terminal, a terminal block and a bottom plate (not shown) are attached, and then varnish is impregnated. Completion.

  As described above, according to the configuration of the present invention, the coil 3 is insulated by the insulating tube 3a from the inner tube 1a of the inner peripheral portion, which is a portion facing the outer peripheral portion of the middle leg 1b of the E-type core 1. As a result of the coating, the spatial distance B between the coil 3 and the EI type core shown in FIG. 2 (B) is larger than the spatial distance A in the conventional reactor 300 shown in FIGS. 4 (A) and 4 (B). It becomes possible to reduce the outer dimensions of the wound coil 3 and to insulate the coil 3 from the EI type core, and the reactor 10 can be miniaturized.

1 E-type core (first core)
DESCRIPTION OF SYMBOLS 1a Outer leg 1b Middle leg 1c Connection part 1d Lower both ends of middle leg 1e Upper both ends of middle leg 2 I-type core (2nd core)
3 Coil 3a Insulation tube 3b Wire 3c Inner diameter lower both corners of coil 3d Inner diameter upper both corners of coil 4 Insulating paper 10 Reactor

Claims (2)

A core formed by joining a first core and a second core made of a magnetic material, and a coil having an insulating film wound around a magnetic leg of the core;
A reactor, wherein at least the coils corresponding to the upper and lower ends of the magnetic legs are covered with an insulating material.   The reactor according to claim 1, wherein the insulator is a heat-shrinkable tube.

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