JP6905852B2 - Bobbin for reactor and reactor - Google Patents

Description

The present invention relates to a reactor and a bobbin for the reactor.

The reactor is a passive element using an inductor, and is used, for example, in a vehicle having a motor drive system such as a hybrid vehicle or an electric vehicle, as a voltage converter for boosting a battery voltage. In addition, the development of non-contact power supply technology for electric vehicles that can be charged externally, such as electric vehicles and plug-in hybrid vehicles, is underway, and reactors are also used in this non-contact power supply device. Since an electric vehicle capable of external charging charges the battery mounted on the electric vehicle by the electric power from the non-contact power supply device installed under the vehicle, the non-contact power supply device is required to be thin. Therefore, a thin reactor (hereinafter, also referred to as a thin reactor) is used for this non-contact power feeding device. Of course, thin reactors are used not only for non-contact power feeding devices for electric vehicles but also for various thin devices.

FIG. 1 shows an example of the core 10 of the thin reactor. The core 10 shown in FIG. 1 is an EE-type core 10 in which two E-type cores (10a, 10b) made of ferrite are arranged so as to face each other. The two E-shaped cores (10a, 10b) face each other with the end faces of the outer legs 11 facing each other and the end faces of the middle legs 12 having a gap 13. Here, the extension direction of each leg (11, 12), that is, the opposite direction of the two E-type cores (10a, 10b) is the vertical direction (or the height direction), and each E-type core (10a, 10b). Defines the left-right direction as the outer leg 11 is formed symmetrically with respect to the middle leg 12, and the direction orthogonal to each of the up-down, left-right directions is the front-back direction.

Each leg of the E-shaped core is short, and when viewed from the front-back direction, a magnetic path that is flat in the vertical direction and wide in the left-right direction is formed. When viewed from the vertical direction, in a rectangular flat plate-shaped part (hereinafter, also referred to as a base part), outer legs are formed along two opposite sides extending in the front-rear direction, and the middle leg is outside in the middle of the two sides. It is formed parallel to the legs.

FIG. 2 is a diagram showing a wound state of the winding 21 in the thin reactor 101 provided with the core 10 shown in FIG. In the following, as shown in the figure, the directions of up, down, front, back, left, and right are defined for convenience. 2 (A) is a plan view of the thin reactor 101 as viewed from above, and FIG. 2 (B) is a cross-sectional view taken along the line aa in FIG. 2 (A). 2 (C) is a rear view of the thin reactor 101 when viewed from the rear, and FIG. 2 (D) is a cross-sectional view taken along the line bb in FIG. 2 (A). As shown in FIG. 2A, in the illustrated thin reactor 101, the winding start portion 21a of the winding 21 is introduced into the region of the core 10 from the front to the rear and wound around the middle leg 12 as a winding axis. After being turned, the winding end portion 21b is led out from the rear to the front. Further, in this example, one winding is spirally wound around the winding shaft to form a one-layer coil 20. Of course, if the winding 21 is thin, two or more layers of coils 20 may be formed. In any case, the winding 21 is wound around the core 10 over the height of the middle leg 12, which is narrow in the vertical direction. The thin reactor is also described in Non-Patent Document 1 below.

Kitagawa Electric Co., Ltd., "Thin High Frequency Reactor", [online], [Search on February 14, 2017], Internet <URL: http://www.kitagawa-denki.co.jp/img/pdf/reactor- flat_type.pdf ＞

As described above, the thin reactor winds the winding around the middle leg of the core that is flat up and down, so when the winding is thick, the winding is spirally wound over many layers like a general coil. Difficult to do. In particular, in a thin reactor that handles a large current (for example, 40A) such as the above-mentioned non-contact power feeding device, a "electric wire" having a large diameter is used for the winding, and a one-layer coil is formed around the winding shaft. It will be wound in a spiral shape. Therefore, as shown in FIG. 2, the windings greatly protrude in the front-rear direction of the core. That is, the size of the conventional thin reactor increases in the front-rear direction in exchange for the thinning in the vertical direction. Further, since the windings protruding from the front and back of the core are far from the region where the core is arranged, there is also a problem that the inductance value decreases. Further, if the number of turns is the same, the length of the spirally wound winding is longer than that of the spirally wound winding, and the DC resistance value is also increased.

Therefore, an object of the present invention is to provide a thin reactor in which the size in the front-rear direction is small, the winding is wound near the core, and the length of the winding can be shortened, and a bobbin used for the reactor. There is.

One aspect of the present invention for achieving the above object is a reactor including a core having a gap in the middle leg, a coil in which a winding is wound around the middle leg, and a bobbin. hand,
With the winding axis direction of the coil as the vertical direction,
The core is flat in the vertical direction, and is provided with outer legs extending in the front-rear direction at both left and right ends of a rectangular flat plate-shaped base portion whose faces are in the left-right direction and the front-back direction, and the middle leg is provided in the front-rear direction in the center of the left-right direction. Formed by extending
When viewed from the vertical direction, the winding is wound around the middle leg via the bobbin in the region where the core is arranged, and outside the region of the core, the front and rear of the base portion. Guided left and right along the end face ,
The bobbin has a flat box shape in the vertical direction, and has a hole in which the middle leg of the core is inserted by connecting the upper and lower surfaces, and a groove formed on the left and right side surfaces with the left and right inner surfaces of the hole as the bottom surface. A guide portion for guiding the winding in the left-right direction at a predetermined vertical position is provided on both the front and rear surfaces.
The guide portion refers to a first guide portion that guides the winding at a vertical position between the upper end and the lower end of the middle leg within a predetermined left-right width range, and the first guide portion. Each of the upper and lower parts has a second guide portion for guiding the winding over the left and right width of the bobbin at a position corresponding to the front and rear end faces of the base portion of the core.
The winding is spirally wound so that a coil for one layer is formed along the groove and the first guide portion from the beginning of winding, and then the winding is wound along the second guide portion. Guided in the left-right direction along the front and rear end faces of the upper base portion of the core and the front and rear end surfaces of the lower base portion, the winding is guided to the first guide portion and the first guide portion. On the other hand, it is formed in a three-layer structure guided by the upper and lower second guide portions, respectively.
It is a reactor characterized by that.

The first guide portion is composed of a pair of tongue pieces having a predetermined left-right width, projecting in the front-rear direction, and facing each other in the up-down direction.
The second guide portion has a normal line in the front-rear direction and extends in the left-right direction to abut the front-rear end surface of the base portion of the core, and the wall portion forward from the upper edge edge and the lower edge edge of the wall portion. Equipped with a pair of upper and lower guide plates that project like eaves
The second guide portion is composed of the upper guide plate and the upper tongue piece, and the lower guide plate and the lower tongue piece.
It may be a reactor characterized by this.

Further, the bobbin holds the winding start portion of the winding and introduces the winding into the groove, and holds the winding end portion of the winding to outward the winding. It is equipped with a winding lead-out unit that leads out in a predetermined direction.
The winding introduction portion is formed of either the front or rear guide portion, and is composed of the guide plate forming a pair of upper and lower second guide portions and notches formed at predetermined left and right positions of the tongue piece.
The winding lead-out portion is formed in either the front or rear guide portion, and is composed of a notch formed in the upper or lower guide plate.
It can also be a reactor characterized by that.

In the reactor described in any of the above, the winding is composed of two or more windings connected in parallel, and each of the two or more windings is located on the inner peripheral side and the outer peripheral side at the upper and lower center positions. After being wound in a spiral shape while maintaining the above speed, the inner peripheral side and the outer peripheral side are switched while being guided by the second guide portion so that the total lengths of the two or more windings are equal. ing,
It can also be a reactor characterized by that.

A bobbin for a reactor including a core having a gap in the middle leg and a coil in which a winding having a predetermined thickness is wound around the middle leg is also within the scope of the present invention. teeth,
With the winding axis direction as the vertical direction,
The bobbin has a vertically flat box shape, and is formed with a hole through which the middle leg of the core is inserted by connecting both the upper and lower sides and the left and right inner surfaces of the hole as bottom surfaces on the left and right side surfaces . It is provided with a groove for guiding the winding in the front-rear direction and a guide portion for guiding the winding in the left-right direction at a predetermined vertical position on both front and rear sides.
The guide portion refers to a first guide portion that guides the winding at a vertical position between the upper end and the lower end of the middle leg within a predetermined left-right width range, and the first guide portion. in each of the upper and lower, have a second guide portion for guiding the winding similar position corresponds to the front and rear end face of the base portion of the core over the lateral width of the bobbin,
The groove, the first guide portion, and the second guide portion each have a vertical width for guiding the winding for one layer.
It is a bobbin for reactors that is characterized by this.

The reactor according to the present invention can reduce the width of the coil protruding from the core arrangement region, and can achieve miniaturization as well as thinning. Further, since the winding of the coil is wound near the core, it is possible to suppress a decrease in the inductance value. Further, the DC resistance value of the winding can be reduced, and the loss of the reactor can be reduced.

According to the bobbin for the reactor according to the present invention, the winding of the coil in the reactor according to the present invention can be easily wound. In addition, the wound state of the winding can be reliably fixed, the insulation performance between the core and the winding can be strengthened, and the withstand voltage performance can be improved. Other effects will be clarified in the following description.

It is a figure which shows the core used for a thin reactor. It is a figure which shows the structure of the conventional thin reactor. It is a figure which shows the reactor which concerns on 1st Example of this invention. It is a figure which shows the reactor which concerns on the 2nd Example of this invention. It is a figure which shows the arrangement relationship of the bobbin and the core in the reactor which concerns on the 2nd Example. It is a perspective view which shows the bobbin provided in the reactor which concerns on the 2nd Example. It is a three-view view which shows the bobbin provided in the reactor which concerns on the 2nd Example. It is a figure which shows the winding state of the winding | winding in the reactor which concerns on 3rd Example of this invention. It is a figure which shows the structure of the guide part in the reactor which concerns on other Examples of this invention.

Examples of the present invention will be described below with reference to the accompanying drawings. In the drawings used in the following description, the same or similar parts may be designated by the same reference numerals and duplicate description may be omitted. Depending on the drawing, unnecessary reference numerals may be omitted in the description.

=== First Example ===
As the reactor according to the first embodiment, a thin reactor having a basic structure common to the reactors according to all the embodiments of the present invention can be mentioned. FIG. 3 shows the structure of the reactor 1a according to the first embodiment. In each of the following drawings including FIG. 3, the directions of up, down, front, back, left, and right specified in FIGS. 1 and 2 are adopted. 3 (A) is a plan view of the reactor 1a of the first embodiment as viewed from above, and FIG. 3 (B) is a cross-sectional view taken along the line cc in FIG. 3 (A). FIG. 3C is a front view of the reactor 1a when viewed from the rear, and FIG. 3D is a cross-sectional view taken along the line dd in FIG. 3A.

As shown in FIG. 3 (A), the reactor 1a is counterclockwise when viewed from above, as shown by the thick dotted arrow in the figure, similarly to the conventional thin reactor 101 shown in FIG. The winding 21 is wound around the middle leg 12 of the core 10. However, the coil 20 does not protrude significantly in the front-rear direction with respect to the region where the core 10 is arranged, and the size in the front-rear direction is smaller than that of the conventional thin reactor 101.

As shown in FIGS. 3B and 3C, the rectangle according to the first embodiment is wound around the winding 21 only in the upper and lower central regions where the core middle legs 12 are arranged. There are a portion 21c and portions (21d, 21e) arranged along the front and rear end faces 15 of a rectangular flat plate-shaped portion (hereinafter, also referred to as a base portion 14) connecting the outer leg 11 and the middle leg 12. With reference to FIG. 3C, the portions (21d, 21e) of the windings 21 arranged along the front and rear end faces 15 of the base portion 14 are formed of the core 10 as shown by the chain line arrows in the drawing. After being led out to the outside, it is bent in either the upper or lower direction and guided along the end surface 15 of the base portion 14. Then, after being bent again in the other direction up and down, it is guided inward of the core 10 and wound around the middle leg 12 which is the winding axis again. That is, as shown in FIG. 3D, one layer of the coil 20 having the middle leg 12 as the winding axis is formed in the arrangement region of the core 10.

As described above, according to the reactor 1a of the present embodiment, since the winding 21 has a multi-layer winding structure (three-layer structure in this example) outside the arrangement region of the core 10, the core is compared with the conventional thin reactor 101. The protrusion width w of the winding 21 in the front-rear direction outside the arrangement region of 10 is shortened, and the size of the reactor 1a in the front-rear direction can be reduced. Further, since the winding 21 is wound in the vicinity of the region of the core 10 over the entire length, the coupling ratio between the winding 21 and the core 10 increases, and the leakage flux decreases. That is, it is possible to suppress a decrease in the inductance value. Further, since the winding 21 is wound in the vicinity of the region of the core 10, the total length of the winding 21 is shortened, the resistance value is also lowered, and the coil loss can be reduced.

=== Second Example ===
The reactor 1a according to the first embodiment of the present invention has a basic structure in which a part of the winding 21 is arranged outside the arrangement region of the core 10 along the front and rear end faces 15 of the base portion 14. There is. In order to fix the winding 21 at a predetermined vertical position outside the arrangement region of the core 10, tape or the winding 21 may be molded with resin or the like. However, since a complicated process for fixing the winding 21 is separately required, it is conceivable to use a bobbin. Therefore, as a reactor according to the second embodiment of the present invention, there is a thin reactor provided with a bobbin that can easily fix the winding 21 to the front and rear end faces 15 of the base portion 14 in the core 10.

FIG. 4 shows a perspective view of the reactor 1b according to the second embodiment. Two E-shaped cores (10a, 10b) flat in the vertical direction are arranged so as to hold the bobbin 30 in the vertical direction. Then, the winding start portion 21a of the winding 21 is introduced into the bobbin 30, and the winding end portion 21b of the winding 21 is derived from the bobbin 30. A part (21d, 21e) of the winding 21 is guided in the left-right direction along the front and rear end faces 15 of the base portion 14 while being wound around the winding shaft of the bobbin 30. Then, at the front and rear ends of the bobbin 30, a guide that guides the winding 21 in the left-right direction at a predetermined vertical position when the winding 21 is led out of the arrangement region of the core 10 during winding. The part 40 is formed. Further, in the reactor 1b according to the second embodiment, the winding start portion 21a and the winding end portion 21b of the winding 21 are introduced into the bobbin 30 from predetermined positions in the front guide portion 40a of the bobbin 30, and from the bobbin 30. Notches (47a to 47c) for deriving are formed.

FIG. 5 is a diagram showing an arrangement state of the bobbin 30 and the core 10 in the reactor 1b according to the second embodiment. The bobbin 30 has a rectangular flat plate shape that is flat in the vertical direction, and the bobbin 30 is sandwiched by E-shaped cores (10a, 10b) that are flat in the vertical direction from above and below. The core 10 illustrated in FIG. 5 has a front-rear length of about 15 cm and a left-right width of about 10 cm as a whole. Since it is difficult to integrally mold the core 10 having a plane region of this size, in this example, the E-shaped cores (10a, 10b) arranged above and below the bobbin 30 are front and rear, respectively. It is divided into four in the direction.

The structure of the bobbin 30 is shown in FIGS. 6 and 7. FIG. 6A is a perspective view of the bobbin 30 viewed from the upper left rear, and FIG. 6B is a perspective view of the bobbin 30 viewed from the upper left front. Further, FIG. 7A is a plan view when the bobbin 30 is viewed from above, and FIG. 7B is a rear view when the bobbin 30 is viewed from the rear. FIG. 7C is a side view of the bobbin 30 when viewed from the right. Hereinafter, the specific structure of the reactor 1 according to the second embodiment will be described with reference to FIGS. 4 to 7.

As shown in FIG. 6, the bobbin 30 has a vertically flat rectangular flat plate shape, and grooves 31 extending in the front-rear direction are formed on the left and right side surfaces. Further, the bobbin 30 is formed with a hole 32 having a strip-shaped planar shape extending in the front-rear direction and connecting the upper surface and the lower surface, and the bobbin 30 has an E-shaped core (10a, which is flat vertically from above and below. When the core 10 is sandwiched by 10b), the middle leg 12 of the core 10 is inserted into the above hole (hereinafter, also referred to as the middle leg insertion hole 32) as shown in FIG. Then, as shown in FIGS. 7A and 7C, the left and right inner surfaces 33 of the middle leg insertion hole 32 and the bottom surface 34 of the groove 31 are formed by a common wall portion 35, and have a front-back relationship with each other. It has become.

Further, the guide portion 40 includes a first guide portion 41 that guides winding portions (FIGS. 3 and 4, reference numerals 21c) arranged at the center positions of the upper and lower sides, and base portions 14 above and below the core 10. It is composed of a second guide portion 42 that guides the winding portions (FIGS. 3 and 4, reference numerals 21d and 21e) arranged at positions along the front and rear end faces 15 in the left-right direction.

As shown in FIGS. 5 to 7, the guide portion 40 includes a pair of upper and lower guide plates 43 that project in the front-rear direction in the front-rear direction over the left-right width of the bobbin 30 at the upper end side and the lower end side of the bobbin 30. It is composed of a pair of upper and lower guide pieces 44 that project like a tongue piece in the front-rear direction from positions corresponding to the upper ends and lower ends of the middle leg 12. The guide plate 43 is formed on the upper edge and the lower edge of the wall surface 37 having the normal direction in the front-rear direction, and the core 10 is formed in the base portion 14 while the middle leg 12 is inserted into the middle leg insertion hole 32. The front and rear end faces 15 are attached to the bobbin 30 by abutting on the wall surface 37.

As shown in FIGS. 7A and 7C, the guide piece 44 is formed in the center of the left and right over a predetermined left and right width. The left-right width of the guide piece 44 is set to be the width when the winding 21 having a predetermined thickness is wound around the middle leg insertion hole 32 a predetermined number of times. Then, the groove-shaped gap extending to the left and right formed by the pair of guide pieces 44 facing each other in the vertical direction becomes the first guide portion 41. Further, the groove-shaped gap extending to the left and right formed by the upper or lower guide plate 43 and the upper or lower guide piece 44 becomes the second guide portion 42.

The winding 21 is wound from the winding start portion 21a until it reaches the left-right width of the guide piece 44 while being guided by the first guide portion 41. When the winding 21 exceeds the left-right width of the guide piece 44 during its winding, the winding 21 is led out from the arrangement region 36 of the core 10 and is bent upward or downward, and then upward. Alternatively, it is guided by the lower second guide portion 42, bent downward or upward at the left and right ends of the guide piece 44, and then introduced into the groove 31.

In the reactor 1b according to the second embodiment, as shown in FIG. 4, the winding 21 is formed in the arrangement region 36 of the core 10 from the upper front along the bottom surface 34 of the groove 31 at the winding start portion 21a. At the end of winding 21b, it is derived from the opening end side of the groove 31 on the right side toward the upper front. Then, as shown in FIGS. 4, 6 (B) and 7 (A), the front guide portion 40a is wound by the notches (47a to 47c) provided in the guide plate 43a and the guide piece 44a. The winding introduction portion 45 that holds the winding start portion 21a of the wire 21 so as to guide it into the groove 31 of the bobbin 30 from a predetermined direction, and the winding end portion 21b of the winding 21 are designated outside the bobbin 30. A winding lead-out portion 46 that holds the winding lead-out portion 46 so as to guide the direction is formed. Specifically, notches (47a, 47b) are provided at the same left and right positions along the bottom surface of the groove 31 of the upper guide plate 43a and the upper guide piece 44a in the front guide portion 40a, and the notches (47a, 47b) are provided. The winding introduction portion 45 is formed by 47b), and the winding start portion 21a of the winding 21 is held by these notches (47a, 47b).

Further, a notch 47c is also formed on the right end side of the upper guide plate 43a in the front guide portion 40a, and this notch 47c serves as a winding lead-out portion 46, and the winding end portion 21b of the winding 21 is formed by this notch 47c. Be retained. When the reactor 1b is incorporated into various devices (non-contact charger or the like) and actually used, the core 10 is fixed to the bobbin 30 by using a tape or a special outer case. Further, the surplus space in the groove 31 is filled with a cushioning material, a resin, or the like to more firmly fix the winding in the correct winding state. In addition, the insulation performance between the core and the winding can be enhanced.

As described above, in the reactor 1b according to the second embodiment, by providing the bobbin 30 described above, the winding 21 projecting in the front-rear direction with respect to the core 10 is arranged at the vertical center position corresponding to the middle leg 12. The base portion 14 can be easily fixed at those positions while being smoothly guided to the positions on both the upper and lower ends corresponding to the front and rear end faces 15. Therefore, the reactor 1b can be provided at a lower cost. Further, since the winding 21 is held by the bobbin 30, the winding 21 can be wound in an orderly manner, and the variation in characteristics between individuals can be reduced. In addition to this, the presence of a bobbin between the core and the winding makes it possible to strengthen the core-winding insulation and improve the withstand voltage performance.

=== Third Example ===
In a reactor that handles a large current, it is necessary to increase the cross-sectional area of the winding, and the diameter of one winding becomes large, which makes it difficult to reduce the thickness. Therefore, two windings connected in parallel may be used to reduce the diameter thickness, that is, the thickness in the vertical direction without changing the substantial cross-sectional area. However, when a one-layer coil is formed by two windings, the length of the winding differs between the inner circumference side and the outer circumference side, and the resistance value and the inductance value change between the inner circumference side and the outer circumference side windings. It ends up. Therefore, the intended characteristics may not be obtained. Therefore, as a third embodiment of the present invention, a reactor capable of reducing the difference in the characteristics of the coils on the inner peripheral side and the outer peripheral side while using two windings will be mentioned.

FIG. 8 shows an example of the winding procedure of the windings (121a, 121b) in the reactor 1c according to the third embodiment. Here, the winding procedure of the windings (121a, 121b) is shown in the order of FIGS. 8A to 8D. The reactor 1c according to the third embodiment is obtained by winding two windings (121a, 121b) connected in parallel to the same bobbin 30 as the reactor 1b of the second embodiment. The bobbins 30 are shown in the drawings so that the positional relationship between the bobbins 30 and the windings (121a, 121b) can be seen in FIGS. 8A and 8B, and in FIGS. 8C and 8D. The bobbin 30 is omitted so that the winding state of the windings (121a, 121b) can be clearly understood, and the winding (121a) wound as a coil 120a for one layer via the first guide portion 41. , 121b) is shown in a simplified manner.

First, as shown in FIG. 8A, the winding start portion 121c of the two windings (121a, 121b) is passed through the winding introduction portion 45 formed in the guide portion 40a in front of the bobbin 30. It is introduced into the groove of the bobbin, and the windings (121a, 121b) are wound around the middle leg insertion hole 32. Then, as shown in FIG. 8B, the winding (121a, 121b) is wound until it reaches the left-right width of the rear guide piece 44, and the winding (121a, 121b) is wound along the first guide portion 41. A coil 120a for one layer is formed by winding the coil 120a. Then, as shown in FIG. 8C, the windings (121a, 121b) that have been wound around the first guide portion 41 are guided by the second guide portion 42. At this time, in the first guide portion 41, the winding 121a on the inner peripheral side and the winding 121b on the outer peripheral side are exchanged so as to be on the outer peripheral side and the inner peripheral side, respectively. Then, the outer peripheral side and the inner peripheral side are appropriately exchanged during the winding of the windings (121a, 121b) so that the total lengths of the two windings (121a, 121b) are the same, and then the winding is derived. The winding end portion 121d of the winding (121a, 121b) is led out in a predetermined direction via the portion 46.

Table 1 below shows the characteristics of the reactor according to the third embodiment.

表１では、内周側と外周側の巻線の入れ替えを行わなかったリアクトルと、入れ替えを行ったリアクトルの特性が示されている。表中の「外周側」と「内周側」は、それぞれ巻き始めにおける巻回状態を示しており、巻線の入れ替えを行わなかったリアクトルでは、各巻線は、巻き終わりまで、その巻回状態を維持する。巻線の入れ替えを行ったリアクトルでは、巻回途上で、内周側と外周側とで入れ替わる。

Table 1 shows the characteristics of the reactor in which the windings on the inner peripheral side and the outer peripheral side are not exchanged and the reactor in which the windings are exchanged. The "outer circumference side" and "inner circumference side" in the table indicate the winding state at the beginning of winding, respectively, and in the reactor in which the windings are not replaced, each winding is in the winding state until the end of winding. To maintain. In the reactor in which the windings have been replaced, the inner peripheral side and the outer peripheral side are exchanged during winding.

As shown in Table 1, the DC resistance value of the winding on the outer peripheral side having a long total length was 0.28 mΩ larger than the DC provided value of the winding on the inner peripheral side of the reactor that was not replaced. In addition, the inductance value was 4.78 μH larger for the winding on the outer peripheral side. On the other hand, in the reactor according to the third embodiment in which the windings were replaced, the difference in DC resistance value was only 0.1 mΩ, and the difference in inductance value was 1.91 μH, which was higher than that of the reactor in which the winding was not replaced. However, the difference in the inductance values of the windings on the inner circumference side and the outer circumference side could be significantly reduced. As described above, in the reactor according to the third embodiment, it was confirmed that the difference between the DC resistance value and the inductance value between the two windings could be reduced, and the loss of the reactor could be reduced. Regarding the reactor according to the third embodiment, the length position at which the winding 121a on the outer peripheral side and the winding 121b on the inner peripheral side are exchanged is the thickness of the windings (121a, 121b) and the left-right width of the guide piece 44. It may be set according to the above. Of course, even if the inner peripheral side and the outer peripheral side are exchanged every time the windings (121a, 121b) are derived from the arrangement region 36 of the core 10 in the bobbin 30, the total extension of the windings on the inner peripheral side and the outer peripheral side remains. Will be the same. In any case, the outer peripheral side and the inner peripheral side of the windings (121a, 121b) are being wound so that the total lengths of the two windings (121a, 121b) connected in parallel are the same. Should be replaced. Of course, the number of windings may be two or more.

=== Other Examples ===
In each of the above embodiments, the core structure is EE type, but a core having another structure such as EI type may be used as long as the core has a gap 13 in the middle leg.

In the second embodiment, the bobbin guide portion is formed of plate-shaped or tongue-shaped protrusions, but the windings are placed at both front and rear ends of the core at the vertical positions corresponding to the front and rear end faces of the core base portion. Any structure may be used as long as it can be distributed and guided to the upper and lower positions corresponding to the middle legs. For example, as shown in FIG. 9, pins (48a, 49a, 48b, 49b) protruding in the front-rear direction are provided at positions corresponding to the four corners of the region where the pair of upper and lower guide pieces 44 are formed, and are provided in the left-right direction. Two adjacent pins (48a and 49a, 48b and 49b) are set as one set, and the upper and lower center area sandwiched between the upper and lower two sets of pins (48a-49a, 48b-49b) is used as the first guide portion 41. The upper and lower sets of the upper set and the lower set may be the second guide portion 42.

In the reactor according to each of the above embodiments, one layer of coil is formed around the winding shaft, and three conductors are guided in the vertical direction on both front and rear ends of the core. If it is a thin winding, a plurality of windings may be arranged in the vertical direction on the first and second guide portions.

In the reactor in each of the above embodiments, the windings are introduced into the core placement region from the upper front and are led out in the same direction, but the windings can be introduced and drawn out in any direction. .. Further, in the reactor using the bobbin similar to that of the second embodiment, a notch for holding the winding may be formed according to the introduction and extraction positions of the winding.

1a, 1b, 101 reactor, 10 cores, 10a, 10b E-type core, 11 outer legs, 12 middle legs, 13 gaps, 14 bases, 15 front and rear end faces of the base, 20 coils 21, 121a, 121b windings, 30 Bobbin, 31 groove, 32 middle leg insertion hole, 36 core placement area, 40, 40a guide part, 41 first guide part, 42 second guide part, 43, 43a guide plate, 44, 44a guide piece, 45 Winding introduction part, 46 winding lead part, 47a to 47c notch

Claims (5)

A reactor having a core having a gap in the middle leg, a coil in which a winding is wound around the middle leg, and a bobbin.
With the winding axis direction of the coil as the vertical direction,
The core is flat in the vertical direction, and is provided with outer legs extending in the front-rear direction at both left and right ends of a rectangular flat plate-shaped base portion whose faces are in the left-right direction and the front-rear direction, and the middle leg is provided in the front-rear direction in the center of the left-right direction. Formed by extending
When viewed from the vertical direction, the winding is wound around the middle leg via the bobbin in the region where the core is arranged, and outside the region of the core, the front and rear of the base portion. Guided left and right along the end face ,
The bobbin has a flat box shape in the vertical direction, and has a hole in which the middle leg of the core is inserted by connecting the upper and lower surfaces, and a groove formed on the left and right side surfaces with the left and right inner surfaces of the hole as the bottom surface. A guide portion for guiding the winding in the left-right direction at a predetermined vertical position is provided on both the front and rear surfaces.
The guide portion refers to a first guide portion that guides the winding at a vertical position between the upper end and the lower end of the middle leg within a predetermined left-right width range, and the first guide portion. Each of the upper and lower parts has a second guide portion for guiding the winding over the left and right width of the bobbin at a position corresponding to the front and rear end faces of the base portion of the core.
The winding is spirally wound so that a coil for one layer is formed along the groove and the first guide portion from the beginning of winding, and then the winding is wound along the second guide portion. Guided in the left-right direction along the front and rear end faces of the upper base portion of the core and the front and rear end surfaces of the lower base portion, the winding is guided to the first guide portion and the first guide portion. On the other hand, it is formed in a three-layer structure guided by the upper and lower second guide portions, respectively.
A reactor characterized by that. In the reactor according to claim 1,
The first guide portion is composed of a pair of tongue pieces having a predetermined left-right width, projecting in the front-rear direction, and facing each other in the up-down direction.
The second guide portion has a normal line in the front-rear direction and extends in the left-right direction to abut the front-rear end surface of the base portion of the core, and the wall portion forward from the upper edge edge and the lower edge edge of the wall portion. Equipped with a pair of upper and lower guide plates that project like eaves
The second guide portion is composed of the upper guide plate and the upper tongue piece, and the lower guide plate and the lower tongue piece.
A reactor characterized by that. In claim 2 ,
The bobbin holds a winding start portion of the winding and introduces the winding into the groove, and holds a winding end portion of the winding to introduce the winding to a predetermined outside. Equipped with a winding lead-out unit that leads in the direction of
The winding introduction portion is formed of either the front or rear guide portion, and is composed of the guide plate forming the upper and lower second guide portions and the notches formed at predetermined left and right positions of the tongue piece.
The winding lead-out portion is formed in either the front or rear guide portion, and is composed of a notch formed in the upper or lower guide plate.
A reactor characterized by that. In the reactor according to any one of claims 1 to 3,
The winding is composed of two or more windings connected in parallel, and each of the two or more windings is spirally wound while maintaining the inner peripheral side and the outer peripheral side at the upper and lower center positions. After that, the inner peripheral side and the outer peripheral side are exchanged while being guided by the second guide portion so that the total lengths of the two or more windings are equal.
A reactor characterized by that. A bobbin for a reactor having a core having a gap in the middle leg and a coil in which a winding having a predetermined thickness is wound around the middle leg as a winding shaft.
With the winding axis direction as the vertical direction,
The bobbin has a vertically flat box shape, and is formed with a hole through which the middle leg of the core is inserted by connecting both the upper and lower sides and the left and right inner surfaces of the hole as bottom surfaces on the left and right side surfaces . It is provided with a groove for guiding the winding in the front-rear direction and a guide portion for guiding the winding in the left-right direction at a predetermined vertical position on both front and rear sides.
The guide portion refers to a first guide portion that guides the winding at a vertical position between the upper end and the lower end of the middle leg within a predetermined left-right width range, and the first guide portion. in each of the upper and lower, have a second guide portion for guiding the winding similar position corresponds to the front and rear end face of the base portion of the core over the lateral width of the bobbin,
The groove, the first guide portion, and the second guide portion each have a vertical width for guiding the winding for one layer.
A bobbin for reactors that is characterized by that.

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