JP2013254802A - Coil device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an expected inductance characteristic regardless of a deviation in shape of a C-shaped core piece in a coil device obtained by combining the C-shaped core piece with a rectangular parallelepiped core piece.SOLUTION: A coil device according to this invention is configured by winding a coil around an annular core, and the core includes a pair of C-shaped core pieces 2 manufactured by winding or laminating a band plate made of metal, a rectangular parallelepiped core piece 3 provided between the pair of C-shaped core pieces, and a magnetic gap part G provided between end faces of the C-shaped core pieces 2 and the rectangular parallelepiped core piece 3. In the coil device, the rectangular parallelepiped core piece 3 is manufactured by a powder magnetic core subjected to pressure molding, and when the height in a lamination direction of the band plate of the end faces of the C-shaped core pieces 2 facing through the magnetic gap part G is defined as T1, and the height of the end face of the rectangular parallelepiped core piece 3 is defined as T2, T2>T1 is satisfied.

Description

  The present invention relates to a coil device that constitutes a reactor, a transformer, and the like in various AC devices, and more particularly to a coil device that is formed by winding a coil around an annular core.

  Conventionally, in this type of coil device, one using a laminated core is known. The laminated core includes, for example, a pair of C-shaped core pieces obtained by dividing an annular wound core member produced by winding a metal strip, and a cut surface of the pair of C-shaped core pieces. It is composed of at least two laminated rectangular parallelepiped core pieces interposed therebetween, and at least four magnetic gap portions interposed between facing surfaces of the C-shaped core piece and the rectangular parallelepiped core piece (see Patent Document 1). .

  In addition, as a laminated core, there is also a laminate core formed by punching a thin plate-like magnetic strip in a C shape and stacking them.

  In the coil device, since the end face of the C-shaped core piece and the end face of the rectangular parallelepiped core piece are opposed to each other via the magnetic gap portion, leakage magnetic flux is generated in the magnetic gap portion, and the gap length Inductance characteristics are determined by the opposed areas of both end faces.

  Therefore, the end face of the C-shaped core piece and the end face of the rectangular parallelepiped core piece are formed in the same shape having the same area, and both end faces are abutted with each other accurately.

Japanese Patent Laid-Open No. 11-40434

  However, in the coil device in which the C-shaped core piece and the rectangular parallelepiped core piece are combined, the C-shaped core piece particularly divides an annular wound core member produced by winding a metal strip, Since the band plate is punched and stacked, the shape of the C-shaped core piece varies to some extent, which causes an error in the relative positions of the two end faces of the C-shaped core piece.

  As a result, when the coil device is assembled by abutting the C-shaped core piece and the rectangular parallelepiped core piece with each other, a displacement occurs between the end face of the C-shaped core piece and the end face of the rectangular parallelepiped core piece. There is a problem that the opposing area of both end faces is smaller than the area of any end face, and the desired inductance characteristics cannot be obtained.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a coil device that combines a C-shaped core piece and a rectangular parallelepiped core piece, and can obtain desired inductance characteristics regardless of variations in the shape of the C-shaped core piece. Is to provide.

The coil device according to the present invention includes:
A coil is wound around an annular core, and the core includes a pair of C-shaped core pieces manufactured by winding or laminating metal strips, and the pair of C-shaped core pieces. In a coil device comprising: a rectangular parallelepiped core piece interposed between: and a magnetic gap portion interposed between end faces of the C-shaped core piece and the rectangular parallelepiped core piece,
The rectangular parallelepiped core piece is made of a compacted powder magnetic core,
When the height in the stacking direction of the strips of the end faces of the C-shaped core pieces facing each other through the magnetic gap portion is T1, and the height of the end faces of the rectangular parallelepiped core pieces is T2,
T2> T1
It is.

When the thickness of the strip of the C-shaped core piece is t,
T2-T1> t
It is desirable that

The C-shaped core piece, when the number of laminated strips is n,
T1 = n × t
It can be.

Further, when the width of the strip of the C-shaped core piece is W1, and the end face of the rectangular parallelepiped core piece is W2, the width orthogonal to the stacking direction of the strip of the end face of the C-shaped core piece is
W2 ≧ W1
Is desirable.

  The area of the end face of the rectangular parallelepiped core piece (T2 × W2) can be formed larger than the area of the end face of the opposing C-shaped core piece (T1 × W1).

  The end face of the rectangular parallelepiped core piece may have a shape obtained by enlarging the shape of the end face of the C-shaped core piece from its center in all directions.

  The coil device includes a square cylindrical bobbin through which the core penetrates, the coil is wound around an outer peripheral surface of the bobbin, and the bobbin has a central portion in which the rectangular parallelepiped core piece is to be accommodated. A space is formed, and a side space into which the tip of the C-shaped core piece is to be inserted is formed on each side of the central space. The cross-sectional shape of the side space is a C-shape. The outer surface of the tip of the C-shaped core piece has a shape obtained by enlarging the shape of the end surface of the C-shaped core piece, and the tip of the C-shaped core piece is inserted into the side space of the bobbin. A synthetic resin is filled between the inner peripheral surface of the bobbin.

  According to the coil device of the present invention, a rectangular parallelepiped shape is included among the end face of a C-shaped core piece produced by winding or laminating a metal strip and the end face of a rectangular parallelepiped core piece made of a dust core. Since the end surface of the core piece is formed larger than the end surface of the C-shaped core piece in the direction of laminating the C-shaped core piece, even if there is some variation in the shape of the C-shaped core piece. The relative positions of the two cores so that the end surface of the C-shaped core piece fits within the contour shape of the end surface of the rectangular parallelepiped core piece in a state where the end surface of the C-shaped core piece abuts the end surface of the rectangular parallelepiped core piece. Can be adjusted. Therefore, even if the end face of the C-shaped core piece is slightly deviated, it can be opposed to the end face of the rectangular parallelepiped core piece, and desired inductance characteristics can be obtained.

  In particular, the C-shaped core piece is likely to vary in the laminating direction due to the number n of the laminated strips, the bonding strength between the strips, etc., but the rectangular parallelepiped core piece is a press-molded body of a dust core. Therefore, dimensional accuracy is high, and even if the C-shaped core piece has a larger end surface than the C-shaped core piece, even if the C-shaped core piece has a variation in the shape of the end surface in the stacking direction, The shaped core piece can be reliably opposed to the end face of the rectangular parallelepiped shaped core piece.

FIG. 1 is a perspective view of a coil device according to the present invention. FIG. 2 is a partially broken plan view of the coil device. FIG. 3A and FIG. 3B are plan views showing an example of the manufacturing process of the C-shaped core piece. FIG. 4 is a perspective view of a rectangular parallelepiped core piece. FIG. 5A and FIG. 5B are explanatory diagrams for comparing the height and width in the stacking direction of the C-shaped core piece and the rectangular parallelepiped core piece. FIG. 6A and FIG. 6B are diagrams for explaining the overlap between the end faces of the C-shaped core piece and the rectangular parallelepiped core piece. FIG. 7 is a perspective view of a bobbin incorporating a rectangular parallelepiped core piece. FIG. 8 is a cross-sectional view of the bobbin of FIG. 7 taken along line BB and viewed in the direction of the arrow.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
As shown in FIG. 1, the coil device according to the present invention is configured by mounting a pair of coil assemblies (5) and (5) on an annular core (1), and each coil assembly (5) has a rectangular tube shape. It consists of a bobbin (8) and a coil (7) wound around the outer peripheral surface of the bobbin (8). The core (1) extends annularly through the two bobbins (8), (8).

The two coils (7) and (7) constituting the two coil assemblies (5) and (5) are formed by winding one conductive wire, and both the coils (7) and (7) are connected to the connecting wire (72 ) Are connected to each other. From both the coils (7) and (7), a winding start end portion (71) and a winding end end portion (73) of the conducting wire are drawn out.
As shown in FIG. 2, the core (1) is composed of a pair of C-shaped core pieces (2) (2) and two rectangular parallelepiped core pieces interposed between the two C-shaped core pieces (2) (2). (3) and (3).

  The core pieces (2) and (2) have a C-shape for easy understanding, but they may be U-shaped or U-shaped. It shall be included in a letter shape.

  In the production of a pair of C-shaped core pieces (2) and (2), a laminated sheet is formed by winding a strip made of a silicon steel plate or an amorphous material, and as shown in FIG. After producing (21), the wound core member (21) is divided along a single cutting line A-A indicated by a broken line in the drawing, thereby forming a pair of left and right as shown in FIG. Divided C-shaped core pieces (2) and (2) are obtained.

  This C-shaped core piece (2) suppresses variations in dimensions in the stacking direction of the strips due to variations in winding strength and misalignment between the winding start end and winding end when the strip is wound. Is difficult. Further, when the strip is wound, there may be a dimensional deviation in the width direction of the strip.

Also, the C-shaped core pieces (2) and (2) can be produced by punching thin magnetic strips into a C shape and then stacking them.
Even in this case, it is difficult to suppress the variation in the dimension in the stacking direction due to the bending of each strip, the bonding strength between the strips, the variation in the number of stacks, and the like.

  Even if it is a C-shaped core by any of the above manufacturing methods, it is difficult to suppress variations in the stacking direction of the strips and variations in the width direction of the strips. In particular, when the variation in the stacking direction of the strips is compared with the variation in the width direction of the strips, it is difficult to suppress the variation in the stacking direction.

On the other hand, the rectangular parallelepiped core piece (3) is made of iron-based, iron-silicon-based, iron-aluminum-silicon-based, iron-nickel-based powder, iron-based, or Co-based amorphous powder as shown in FIG. It can be produced by compacting into a rectangular parallelepiped shape.
Since the rectangular parallelepiped core piece (3) is a compacted body of a powder magnetic core, the dimensional accuracy is higher than that of the C-shaped core piece (2), and the dimensional variation of the product can be reduced.

  As shown in FIGS. 5 and 6, for the C-shaped core piece (2), the thickness of the strip is t, the height in the stacking direction of the strip at the divided end surface is T1, and the stacking direction is in the end surface. The width in the direction orthogonal to is W1.

  The rectangular parallelepiped core piece (3) is parallel to the laminating direction of the strips at the end face facing the end face of the C-shaped core piece (2) in the assembled state, as shown in FIGS. The height is T2, and the width in the direction orthogonal to the stacking direction is W2.

At this time, as shown in FIGS. 5 and 6, the rectangular parallelepiped core piece (3) is formed such that the height T2 is larger than the height T1 of the C-shaped core piece (2) in the winding direction. . That is,
T2> T1
To satisfy.

  Here, the reason why T1 and T2 are defined as described above is that the C-shaped core piece (2) has large variations in dimensions in the stacking direction in the stacking direction and the width direction.

  When the C-shaped core piece (2) has a variation in the width direction, W2> W1, and when the variation in the width direction is small, the width W1 and the width W2 of the rectangular parallelepiped core piece (3) are W1. = W2 may be set.

  As a result, the rectangular parallelepiped core piece (3) has the sum of the height and width orthogonal to the magnetic path, preferably the height in the stacking direction of the C-shaped core piece (2), preferably the height. The sum of the height and the width orthogonal to the magnetic path, preferably higher than the height. Therefore, even if the C-shaped core piece (2) has a variation in the stacking direction, the C-shaped core piece (2) and the end face of the rectangular parallelepiped core piece (3) are in contact with each other. The relative position of both core pieces (2) and (3) can be adjusted so that the end face of the core piece (2) is within the contour shape of the end face of the rectangular parallelepiped core piece (3). The facing area between the end face of the C-shaped core piece (2) and the end face of the rectangular parallelepiped core piece (3) is exactly the same as the area (T1 × W1) of the end face of the C-shaped core piece (2). Become.

Preferably, when the thickness of the strip of the C-shaped core piece (2) is t,
T2-T1> t
And Thereby, when the winding core member (21) is cut, even if the winding start end or winding end end of the strip is shifted, the C-shaped core piece (2) is moved to the end face of the rectangular parallelepiped core piece (3). It can be contained within the contour shape.

Considering the variation in the winding strength of the strip,
T2−T1 ≧ 2 × t to 10 × t
Is more preferable.
Further, T2-T1 is desirably 0.5 mm or more.

  On the other hand, an increase in T2-T1 leads to an increase in the size of the coil device and material loss. Therefore, the upper limit of T2-T1 is desirably 2 mm or less.

Here, when determining T2 of the rectangular parallelepiped core piece (3), when it is difficult to measure the actual size T1 of the C-shaped core piece (2), the C-shaped core piece (2) is When the number of laminated strips is n,
T1 = n × t
As described above, T2 can be determined by replacing T1 with n × t.

  The rectangular parallelepiped core piece (3) has a cross section (T2 × W2) orthogonal to the magnetic path larger than the cross section (T1 × W1) orthogonal to the magnetic path of the C-shaped core piece (2). Therefore, it is desirable that the end face of the rectangular parallelepiped core piece (3) is formed in a larger shape than the end face of the C-shaped core piece (2).

  As the end face of the rectangular parallelepiped core piece (3), a shape obtained by enlarging the shape of the end face of the C-shaped core piece (2) from its center to the four directions can be adopted. That is, as shown in FIGS. 5 (b) and 6 (b), the end face of the rectangular parallelepiped core piece (3) has the shape of the end face of the tip of the C-shaped core piece (2), and the C-shaped core piece. It has a shape enlarged by T2-T1 in the stacking direction of the piece (2) and expanded by a predetermined distance W2-W1 in the width direction orthogonal to the stacking direction.

As shown in FIGS. 7 and 8, the rectangular parallelepiped core piece (3) having the above-described configuration is accommodated in a rectangular tube-shaped bobbin (8) formed by insert molding or the like.
The bobbin (8) may be molded as an integral part as shown in these drawings, or two or more molded bodies may be joined in advance to form an integral part. Although not shown, two or more molded bodies may be prepared, and these molded bodies may be assembled and joined in a state where the rectangular parallelepiped core piece (3) is inserted in advance.

  When the rectangular parallelepiped core piece (3) is inserted later, the bobbin (8) has a rectangular parallelepiped core piece (3) at the approximate center of one surface thereof, the approximate center of the outer peripheral side which is the upper side in FIGS. ) Can be inserted.

  Further, as shown in FIG. 8, ribs (85) and (86) for clamping the rectangular parallelepiped core piece (3) from both sides are projected inwardly on the inner peripheral surface of the bobbin (8), and the mold resin At both ends of the wall (81), flanges (82) project outwardly. Here, the thickness of the ribs 85 and 86 is the same as the gap length G to be formed between the C-shaped core piece 2 and the rectangular parallelepiped core piece 3 as shown in FIG. Is formed.

  As shown in FIG. 7, one brim (82) of the bobbin (8) has one end face among the four end faces forming a quadrangular outer shape for locking the coil winding as will be described later. The two locking grooves (83) and (84) are recessed.

  In the above-described bobbin (8), a pair of side spaces (80) and (80) are formed on both sides of the central space facing the opening (88). Here, the central space and the side space (80) have the same shape as the rectangular parallelepiped core piece (3) in a cross section perpendicular to the magnetic path of the core (1). The core piece (3) is accommodated without forming a gap around it. That is, both the central space and the side space (80) have the same inner dimension in the direction parallel to the laminating direction of the strips of the C-shaped core piece (2) as T2, which is the same as the rectangular parallelepiped core piece (3). The inner dimension in the orthogonal direction can be formed to be W2.

  In addition, after inserting the rectangular parallelepiped core piece (3), the opening (88) is sealed with a rectangular resin lid (87) or wrapped with an insulating tape or the like in the central space. It is desirable that the core piece (3) does not fall out of the central space or rattle in the central space.

A coil (7) is wound around the outer peripheral surface of the bobbin (8) as shown in FIGS.
The ends of the pair of C-shaped core pieces (2) and (2) are inserted into the pair of side spaces (80) and (80) of the bobbin (8) as shown in FIG. Is configured.
Since the side space (80) (80) has the same shape as the cross section of the central space in which the rectangular parallelepiped core piece (3) is accommodated, the end face is smaller than the rectangular parallelepiped core piece (3). The piece (2) can be fitted in the side space (80) (80) with a margin. Therefore, even if the C-shaped core piece (2) has variations in the stacking direction or in the width direction perpendicular to the stacking direction, the C-shaped core piece (2) can be easily inserted from the end face.

  That is, even if there is some variation in the shape of the C-shaped core piece (2), the end face of the C-shaped core piece (2) and the end face of the rectangular parallelepiped core piece (3) are in contact with each other. The relative position of both core pieces (2) and (3) can be adjusted so that the end face of the C-shaped core piece (2) is within the contour shape of the end face of the rectangular parallelepiped core piece (3). Therefore, the facing area between the end face of the C-shaped core piece (2) and the end face of the rectangular parallelepiped core piece (3) is exactly the same as the area of the end face of the C-shaped core piece (2) as shown in FIG. Will match.

  More specifically, the variation of the C-shaped core piece (2) is allowed up to T2-T1 in the laminating direction of the strip and W2-W1 in the width direction.

  When the end face of the rectangular parallelepiped core piece (3) is formed larger by T2-T1 than the height in the stacking direction of the C-shaped core piece (2) and the width direction is the same (W1 = W2) The cross-sectional shape of the side space (80) of the bobbin (8) is fitted with a margin T2-T1 only in the stacking direction of the C-shaped core piece (2).

  In the manufactured core (1), the rib (85) (86) is interposed between the end face of the C-shaped core piece (2) and the end face of the rectangular parallelepiped core piece (3). In the magnetic path (1), predetermined gaps G are formed at four locations.

As shown in FIG. 2, the two side spaces of each bobbin (8) can be filled with adhesive (9) by surrounding the end of the C-shaped core piece (2). The C-shaped core piece (2) can be fixed to the bobbin (8) by the adhesive (9).
Further, the adhesive (9) can be filled in a gap formed between the end face of the rectangular parallelepiped core piece (3) and the end face of the C-shaped core piece (2), thereby the rectangular parallelepiped core piece. (3) and the C-shaped core piece (2) can be connected and fixed to each other.

  In one embodiment of the assembly process of the coil device, as shown in FIG. 1, a pair of bobbins (8) and (8) containing a rectangular parallelepiped core piece (3) are arranged in series, and both bobbins (8 ) Winding is applied to the outer peripheral surface of (8). In the winding process, first, winding is sequentially performed on the bobbin in one direction while the winding start end portion (71) of the conducting wire is locked in one locking groove (83) of one bobbin (8). After the application, the wire is folded and wound sequentially in the opposite direction, and the conductor is locked in the other locking groove (84) of the bobbin.

  Subsequently, the crossover wire (72) that has passed through the locking groove (84) is locked to one locking groove (83) of the other bobbin (8), and in this state, the bobbin is unidirectional. After the sequential winding, it is folded back and sequentially wound in the reverse direction, and the conductor is locked to the other locking groove (84) of the bobbin, and the winding end end (73 ) Pull out.

  Next, one bobbin (8) is rotated 180 degrees with respect to the other bobbin (8), and both bobbins (8) and (8) are brought into a parallel positional relationship in which the buttocks contact each other as shown in FIG. Line up. Along with this, the connecting wire (72) extending from one coil (7) to the other coil (8) bends in an arc shape, and the adjacent locking grooves (84) of both bobbins (8), (8). (83) will be stretched at the shortest distance.

  After the winding process of the coils (7) and (7) on both bobbins (8) and (8), the tip ends of a pair of C-shaped core pieces (2) and (2) are inserted into both bobbins (8) and (8). Then, a pair of C-shaped core pieces (2) and (2) are fixed to both bobbins (8) and (8). Here, the cross-sectional shape of the side space (80) of the bobbin (8) is T2-T1 in the stacking direction and W2-W1 in the width direction than the cross-sectional shape of the tip of the C-shaped core piece (2). Since there is a margin, the insertion work can be easily performed even when the C-shaped core piece (2) has variations during winding or stacking of the strips.

Prior to the insertion of the C-shaped core piece (2), an appropriate amount of adhesive is filled in the side space of the bobbin (8), and the end of the C-shaped core piece (2) is filled with the adhesive. May be fixed to the bobbin (8). The adhesive filled in the side space of the bobbin (8) flows backward from the back of the side space to the opening side with the insertion of the C-shaped core piece (2), and as shown in FIG. The end portion of the letter-shaped core piece (2) is covered with a wide area, and as a result, the C-shaped core piece (2) and the bobbin (8) are bonded in a large area, thereby obtaining a larger adhesive force. I can do it.
Further, the adhesive (9) filled in the side space of the bobbin (8) is also filled in a region to be a magnetic gap between the C-shaped core piece (2) and the rectangular parallelepiped core piece (3). Thus, the C-shaped core piece (2) and the rectangular parallelepiped core piece (3) can be connected and fixed to each other.

  In the coil device assembled in this way, the facing area between the end face of the C-shaped core piece (2) and the end face of the rectangular parallelepiped core piece (3) is the area of the end face of the C-shaped core piece (2). Since it exactly matches (T1 × W1), the desired inductance characteristic can be obtained.

  In addition, by using a powder magnetic core obtained by pressure-molding the rectangular parallelepiped core piece (3) and a laminated body of the C-shaped core piece (2), it is possible to obtain composite characteristics by combining these different characteristics. it can.

  In the coil device of the present invention, even if the C-shaped coil piece (2) has a variation in the stacking direction or a displacement in the width direction, the deviation can be eliminated when the coil device is assembled. The characteristics can be homogenized.

  In addition, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim. For example, although the rectangular parallelepiped core pieces (3) are arranged one by one between the C-shaped core pieces (2) in the above embodiment, a plurality of rectangular parallelepiped core pieces (3) are arranged between the C-shaped core pieces (2). May be. In this case, the dimensions of the rectangular parallelepiped core pieces (3) at both ends that face at least the C-shaped core piece (2) may be adjusted along the above. Moreover, the winding method and the locking method of the conducting wire with respect to the bobbin (8) are not limited to the above-mentioned method.

(1) Core
(2) C-shaped core piece
(3) Cuboid core piece
(8) Bobbin
(80) Side space T1 Height in the stacking direction of the C-shaped core piece T2 Height of the rectangular parallelepiped core piece W1 Width of the C-shaped core piece in the strip direction W2 Width of the rectangular parallelepiped core piece

Claims (7)

A coil is wound around an annular core, and the core includes a pair of C-shaped core pieces manufactured by winding or laminating metal strips, and the pair of C-shaped core pieces. In a coil device comprising: a rectangular parallelepiped core piece interposed between: and a magnetic gap portion interposed between end faces of the C-shaped core piece and the rectangular parallelepiped core piece,
The rectangular parallelepiped core piece is made of a compacted powder magnetic core,
When the height in the stacking direction of the strips of the end faces of the C-shaped core pieces facing each other through the magnetic gap portion is T1, and the height of the end faces of the rectangular parallelepiped core pieces is T2,
T2> T1
The coil apparatus characterized by being. When the thickness of the strip of the C-shaped core piece is t,
T2-T1> t
The coil device according to claim 1. The C-shaped core piece, when the number of laminated strips is n,
T1 = n × t
The coil device according to claim 1 or 2, wherein When the width of the strip of the C-shaped core piece is W1, and the end face of the rectangular parallelepiped core piece is W2, the width perpendicular to the stacking direction of the strip of the end face of the C-shaped core piece is
W2 ≧ W1
The coil device according to any one of claims 1 to 3. When the width of the strip of the C-shaped core piece is W1, and the end face of the rectangular parallelepiped core piece is W2, the width perpendicular to the stacking direction of the strip of the end face of the C-shaped core piece is
The area (T2 × W2) of the end face of the rectangular parallelepiped core piece is formed to be larger than the area (T1 × W1) of the end face of the opposing C-shaped core piece. The coil apparatus as described in.   The coil device according to any one of claims 1 to 5, wherein an end surface of the rectangular parallelepiped core piece has a shape obtained by enlarging the shape of the end surface of the C-shaped core piece from the center toward the four directions. .   A bobbin having a rectangular tube shape through which the core passes is provided, and the coil is wound around an outer peripheral surface of the bobbin. A central space in which the rectangular parallelepiped core piece is to be accommodated is formed in the bobbin. In addition, a lateral space into which the tip of the C-shaped core piece is to be inserted is formed on both sides of the central space, and the cross-sectional shape of the lateral space is the end surface of the C-shaped core piece. The outer peripheral surface of the tip portion of the C-shaped core piece and the inner periphery of the bobbin in a state where the tip portion of the C-shaped core piece is inserted into the side space of the bobbin. The coil device according to any one of claims 1 to 6, wherein a synthetic resin is filled between the surface and the surface.

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