JP6284261B2 - Mold transformer and method of assembling iron core used for mold transformer - Google Patents

Description

  The present invention relates to a mold transformer and a method for assembling an iron core used in the mold transformer.

  One type of transformer is called a molded transformer. This mold transformer has a so-called mold configuration in which a coil is integrated in an embedded state in a cylindrical molded body (mold) made of a resin material in order to obtain good insulation characteristics. The primary and secondary coils are formed by winding a wire such as a flat wire. This mold is made of, for example, a mixed resin of an epoxy resin and a filler.

  The molded transformer is configured by mounting the above-described resin-molded coil on an iron core constituting a magnetic circuit. There are various types of structures of the iron core, and one of them is formed by appropriately stacking rectangular blocks made of band-like silicon steel plates to form a flat square-shaped laminated iron core. This type of molded transformer is disclosed in, for example, Patent Document 1.

JP 2011-1298341 A

  When the transformer is energized, it generates heat from the iron core and coil and dissipates the heat into the air, but the temperature rises in inverse proportion to the heat dissipation performance. Therefore, the influence of heat generation cannot be ignored in the conventional mold transformer. That is, the heat generated by the mold transformer includes heat generation of the coil accompanying energization of the coil and heat generation of the iron core accompanying excitation of the iron core. Therefore, if such heat generation cannot be cooled, there is a problem that the temperature of the mold transformer rises to a specified value or more. If the loss of the transformer is not changed to solve this problem, there is a means to forcibly cool the mold transformer with air blowing means such as a cooling fan. For example, noise increase due to additional equipment such as a large fan, the number of parts There was a problem such as an increase in costs.

In order to solve the above-described problem, a molded transformer according to the present invention is configured by connecting at least both ends of a yoke portion made of a pair of magnetic bodies with legs made of a magnetic material, the yoke portion and Each of the leg portions is laminated with a plurality of strip-like blocks being alternately shifted in the longitudinal direction, and an iron core whose joint portion is inclined, and a molded coil mounted on the leg portion. Assumption. (1) And based on the premise, the surface shape of the outer peripheral surface of the yoke portion is made uneven in the stacking direction of the blocks, and the unevenness protrudes outward from the first part and the first part. The second portion to be formed and the third portion that is lowered inward from the first portion , the surface shape of the outer peripheral surface and the inner peripheral surface of the leg portion is flat in the direction in which the blocks are stacked. It was. (2) Moreover, the surface shape of both the outer peripheral surface of the said yoke part and the outer peripheral surface of the said leg part is made uneven | corrugated in the lamination direction of the said block , The said unevenness | corrugation is the 1st site | part and the 1st site | part It was made to comprise in 3 steps | paragraphs of the 2nd site | part which protrudes outside rather than the 1st site | part, and the 3rd site | part which fell below the said 1st site | part .

  The heat generated in the iron core is radiated from the surface of the iron core. Since the outer peripheral surface faces the external space of the iron core, the heat generated in the iron core is radiated to the outside as it is. Then, in the present invention, the outer peripheral surface, which has been a flat surface in the past, is made uneven in the stacking direction, whereby the surface area of the heat radiation portion is increased and the cooling effect is improved. Along with this, the cooling effect of the heat generated from the coil is also improved, so that the loss of the coil can be increased to the temperature increase specified value as the coil temperature increase value decreases. For this reason, since the cross-sectional area of a conductor can be made small, size reduction of a coil can be achieved. In addition, when the cross-sectional area of the conductor is left as it is, the value of the current that is energized to the predetermined temperature rise can be increased. This increases the capacity of the transformer. This is the same whether the transformer is cooled by air or by air. Therefore, for example, the iron core and thus the entire molded transformer can be reduced in size, and if the dimensions are the same, the capacity of the transformer can be increased. In the present invention, irregularities are formed on at least the outer circumferential surface, but irregularities may also be formed on the inner circumferential surface as shown in the embodiments and the like. In the present invention, since the cooling effect is improved, it is not necessary to install an additional device for the fan, and even when it is installed, it is possible to reduce the size of the fan or to reduce the capacity of the fan. The capacity can be reduced.

(3) The unevenness may be a fin structure in which concave grooves and ridges are repeatedly arranged. “Repeated grooves and ridges” are not limited to those in which grooves and ridges are alternately formed for each block to be laminated. For example, the grooves and ridges are alternately repeated for each block. It may be a thing. In that case, the plurality of blocks may be the same number or different. If they are different, one may be one. Further, the protrusion amount of the ridge (depth of the groove) may or may not be constant. That is, it is only necessary to repeatedly form a section constituting the groove and a section constituting the ridge (the number of blocks constituting each section is arbitrary). As in the embodiment, it is preferable that the concave grooves and the ridges are alternately repeated with the same number of blocks, since they can be easily assembled using common parts.

(4) It is good to provide the center leg part which connects the intermediate parts of the said yoke part, and make the surface shape of the side surface of the center leg part uneven | corrugated in the lamination direction of the said block. The present invention is also applicable to a three-phase mold transformer, and if the side surface of the central leg is uneven, the cooling effect may be improved. In the three-phase type mold transformer, the surface shape of the side surface of the central leg is uneven, which is included in the above inventions (1) and (2) .

(5) A slit may be formed with a gap at least at one location between the blocks to be stacked. By providing a slit, the internal space of the iron core (the space surrounded by the leg and yoke part) is connected to the outside of the iron core, and the heat of the internal space heated by the heat generated from the inner peripheral surface of the iron core For example, it escapes to the outside by natural convection, and the heat dissipation effect is enhanced, and the cooling effect of the iron core is improved. By providing the slit, the surface facing the slit of the iron core is also cooled, and for example, the temperature of the entire iron core can be made close to uniform.

(6) It is good to arrange a ventilation means outside the iron core to be a forced air cooling type. The air blowing means corresponds to what is called a fan / blower in the embodiment. Various types such as those that simply blow air against the iron core and those that blow cold air can be applied. In particular, when the slit is provided as in (5) , the wind from the blowing means passes through the slit, so that the wind also hits the iron core and the cooling efficiency is improved. Further, it is preferable because heat that has accumulated in the internal space of the iron core can be forcibly exhausted to the outside by the wind passing through the slit. In addition, when the slit is provided, for example, even if the wind of the blowing means hits one surface of the iron core, it is preferable because the wind can be sent to the other surface through the slit. Furthermore, since the slits are also formed in the leg portions on which the mold coil is mounted, the wind from the blowing means moves through the slit and hits the inner peripheral surface of the mold coil. Thus, the area where the mold coil is directly exposed to wind increases, and the cooling efficiency for the coil is improved.

(7) The method for assembling the iron core according to the present invention is a method for assembling the iron core used in the molded transformer according to any one of (1) to (6) above, and is a joint for constituting the yoke portion. The iron part block and the leg part block for constituting the leg part are in the form of a strip plate and the joints at both ends are inclined, and the yoke part block and the leg part block are elongated. One of the yoke part block for forming the yoke part and the leg block for constituting the leg part are alternately laminated in the short side direction as well as the longitudinal direction. The projections and depressions shifted to the three steps are formed. It is only necessary to easily manufacture a shape in which unevenness is repeated in the stacking direction on the outer peripheral surface simply by shifting in the short direction.

  In the present invention, the cooling efficiency of the iron core is improved. Therefore, it is possible to reduce the size of the iron core and the molded transformer as a whole, and it is possible to increase the capacity of the transformer if the dimensions are the same.

(A) is the front view which shows suitable 1st embodiment of the molded transformer which concerns on this invention, (b) is the side view, (c) is the top view. It is a partial expansion perspective view which shows the iron core used as the principal part of 1st embodiment. (A) is a front view of an iron core, (b) is aa 'sectional drawing. It is a figure which shows each block which comprises an iron core. It is a figure explaining the method of assembling an iron core using each block. It is a figure explaining the method of assembling an iron core using each block. It is a partial expansion perspective view which shows the iron core used as the principal part of 2nd embodiment. It is a side view which shows the iron core used as the principal part of 2nd embodiment. It is a partial expansion perspective view which shows the iron core used as the principal part of 3rd embodiment. It is a front view of the iron core used as the principal part of 3rd embodiment. It is a figure which shows each block which comprises an iron core. It is a figure explaining the method of assembling an iron core using each block. It is a partial expansion perspective view which shows the iron core used as the principal part of 4th embodiment.

  FIG. 1 shows an external view of a first embodiment of a molded transformer according to the present invention. The mold transformer of this embodiment is a single phase type mold transformer. The mold transformer 10 of this embodiment includes an iron core 11 that constitutes a magnetic circuit, and a mold coil 12 that is attached to the iron core 11. The iron core 11 of the present embodiment is a stacked iron core, and includes a pair of leg portions 14 extending vertically and a pair of yoke portions (also referred to as “yoke portions”) 15 disposed vertically and extending in the horizontal direction. Thereby, the iron core 11 is formed in a planar substantially rectangular shape. As will be described later, the leg portion 14 and the yoke portion 15 are each formed by laminating a number of band-shaped directional silicon steel plates each having a predetermined shape, and an end portion of the adjacent leg portion 14 and an end portion of the yoke portion 15. Connect the parts together. The upper yoke portion 15 is covered with a U-shaped transformer fitting 16 from above, and the lower yoke portion 15 is fitted with the U-shaped transformer fitting 16 from the bottom side.

  Although not specifically shown, the molded coil 12 has a double cylindrical structure. That is, the primary mold coil is located outside, and the secondary mold coil is inserted into the inner periphery of the primary mold coil. And it is set as the arrangement | positioning which inserts the leg part 14 in the inner periphery of the secondary side mold coil. A primary side terminal 17 is attached to the winding start end side and the winding end end side of the primary mold coil. The secondary side terminal 18 is attached to the winding start end side and the winding end end side of the secondary side mold coil. Since these basic configurations are the same as those of a conventional molded transformer, a detailed description thereof will be omitted.

  As shown in FIGS. 2 and 3, in this embodiment, the upper and lower surfaces of the yoke portion 15 disposed above and below the iron core 11 are repeatedly uneven along the thickness direction (the direction in which the directional silicon steel plates are laminated). I did it. That is, the ridges 15 a and the grooves 15 b formed so as to extend along the upper side and the lower side (direction orthogonal to the thickness direction) of the yoke portion 15 are alternately arranged in the thickness direction of the yoke portion 15. . FIG. 2 shows a state in which irregularities are repeatedly formed in the thickness direction in the upper surface portion of the yoke portion 15 located above, but as shown in FIG. 3, the yoke portion 15 located above is shown. Convex and concave portions 15a and concave grooves 15b are alternately formed in the thickness direction on the lower surface portion of the substrate. In addition, on the upper and lower surfaces of the yoke portion 15 positioned below, the ridges and the grooves are alternately and repeatedly formed in the thickness direction.

  In this way, by adopting a fin structure in which the ridge and the groove are repeatedly formed, the ridge 15a protruding from the back surface of the groove 15b as compared with the conventional type in which the upper surface and the lower surface of the yoke portion 15 are flat. The surface area, that is, the heat radiation area is increased by the area of the front and rear surfaces. Therefore, the cooling efficiency of the iron core 11 is increased, and the heat of the iron core generated with the excitation is efficiently radiated, and the temperature rise of the iron core can be suppressed and reduced. Therefore, it becomes possible to reduce the size of the iron core, and thus the entire molded transformer, and to reduce the weight accordingly. Moreover, if the dimensions are the same, the capacity of the transformer can be increased.

[Assembly method of iron core]
As described above, the iron core 11 of the present embodiment is a stacked iron core, and is formed in a substantially rectangular shape in a plane by laminating many directional silicon steel plates having a predetermined shape. Accordingly, a plurality of directional silicon steel plates stacked together are used as one block, and ridges and grooves are alternately appeared in the stacking direction by alternately shifting the blocks up and down. In this embodiment, since it is shifted up and down every two blocks, as shown in FIG. 3 (b), when attention is paid to a certain block, when the ridge 15a is formed on the lower side, When the concave groove 15b is formed (for example, the block at the left end or the right end in FIG. 3B), and the concave groove 15b is formed on the lower side, a ridge 15a is formed on the upper side of the same block (for example, In FIG. 3B, the third and fourth blocks from the end, etc.).

  By assembling the blocks while shifting the blocks up and down in this manner, for example, the outer shape of the directional silicon steel plate constituting the directional silicon steel plate constituting the yoke portion 15 can be the same predetermined shape. The same applies to the grain-oriented silicon steel sheets constituting the legs 14. Therefore, the cross-sectional area through which the magnetic flux passing through the iron core 11 when viewed in units of blocks can be the same as the conventional one that is not shifted up and down.

  A specific method of assembling the iron core 11 while alternately shifting up and down in units of blocks as described above is as follows. First, both the yoke part 15 and the leg part 14 are comprised using a directional silicon steel plate. As shown in FIG. 3, the joint surface between the yoke portion 15 and the leg portion 14 is inclined 45 degrees, and the joint surfaces are appropriately overlapped to form a so-called frame-shaped iron core. In the present embodiment, the joint is inclined at 45 degrees, but the angle can be any angle (acute angle) such as 30 degrees or 60 degrees.

  FIG. 4 shows each block formed by laminating a predetermined number of directional silicon steel plates for constituting the leg portion 14 and the yoke portion 15 respectively. 4A shows the first leg block 21, and FIG. 4B shows the second leg block 22. FIG. 4C shows the first yoke part block 23, and FIG. 4D shows the second yoke part block 24. Each of the blocks 21 to 24 is configured by stacking a plurality of (for example, 12) band-shaped directional silicon steel plates. Each directional silicon steel plate has an isosceles trapezoidal plane shape in which both ends in the longitudinal direction are inclined 45 degrees in the rolling direction.

  The first leg block 21 and the second leg block 22 have the same external dimensions, but are different in the formation positions of the guide through holes 21a and 22a. Specifically, both of the two through holes 21a and 22a are formed, and each of the through holes 21a and 22a is disposed at the center position in the short direction, and two through holes (21a and 21a, The interval A between 22a and 22a) is set equal, but the arrangement position in the longitudinal direction is shifted. The first leg block 21 is provided with two through holes 21a so as to be a target (equal distance from the center position) with respect to the center position in the longitudinal direction. The second leg block 22 is arranged such that the midpoint P between the two through-holes 22a in the set is shifted from the center position in the longitudinal direction of the second leg block 22 by a distance B. Thereby, the through holes 21a and 22a provided in both the blocks 21 and 22 have a positional relationship shifted by a distance B in the longitudinal direction of the blocks. This distance B corresponds to the amount of shift when shifting up and down alternately in units of blocks, that is, the amount of protrusion from the back surface of the groove 15b of the ridge 15a, and is 10 mm in this embodiment, for example. Therefore, when both the blocks 21 and 22 are overlapped so that the through hole 21a of the first leg block 21 and the through hole 22a of the second leg block 22 face each other and coincide with each other, the first leg block 21 is overlapped. In the second leg block 22, the first long sides 21b and 22b and the second long sides 21c and 22c are overlapped with each other, and both the oblique sides 21d and 22d in the longitudinal direction are shifted by a distance B. .

  The first yoke part block 23 and the second yoke part block 24 have the same outer dimensions, but are different in the formation positions of the guide through holes 23a, 24a. Specifically, both of the through holes 23a and 24a are formed, and the through hole 23a of the first yoke portion block 23 has a predetermined distance (B / 2) downward from the center position in the lateral direction. ) And the through hole 24a of the second yoke part block 24 is arranged so as to be shifted from the center position in the short direction by a predetermined distance (B / 2) upward in the drawing. Thereby, when it piles up so that the outer periphery of the block 23 for 1st yoke parts and the block 24 for 2nd yoke parts may correspond, the through-hole 23a of the block 23 for 1st yoke parts and the 2nd yoke part use The through holes 24a of the block 24 have a positional relationship shifted by a distance B in the short direction. Therefore, when both the blocks 23 and 24 are overlapped so that the through hole 23a of the first yoke part block 23 and the through hole 24a of the second yoke part block 24 face each other and match, The first long side 23b of the block 23 protrudes outwardly from the first long side 24b of the second yoke part block 24 by a distance B, and the second long side 24c of the second yoke part block 24 It will be in the state which protruded and shifted | deviated by the distance B outside 2nd long side 23c of the block 23 for primary iron parts.

  In the present embodiment, the first and second yoke part blocks 23 and 24 are alternately shifted by a predetermined distance X in the longitudinal direction when stacked. This distance X is equal to the distance B shifted up and down in the present embodiment, but may be different. By displacing in this way in the longitudinal direction, each yoke part block 23, 24 comes to protrude sideways by a predetermined distance X alternately on one side. Similarly, the first and second leg blocks 21 and 22 are stacked while being alternately shifted by a predetermined distance X in the longitudinal direction. At this time, the adjacent yoke block and leg block are reversed in direction, and the protruding tip of each block enters the other party's retracted space.

  Further, in the present embodiment, the shifting directions of the two yoke block at the same product position are also reversed. Similarly, the shifting directions of two leg blocks in the same product position are also reversed.

  Specifically, the blocks are arranged and stacked in the product order shown in FIGS. As shown in FIG. 5, at the same product position, the first leg block 21, the second leg block 22, the first yoke block 23, and the second yoke block 24 are appropriately arranged. I try to arrange it. For example, FIG. 5A shows an arrangement pattern used for the first, fifth, ninth, etc. stacking order, the first leg block 21 on the left side in the figure, and the second leg block on the right side in the figure. 22, the second yoke part block 24 is arranged on the upper side in the figure, and the first yoke part block 23 is arranged on the lower side in the figure. The upper second yoke part block 24 is shifted to the right side, and the lower first yoke part block 23 is shifted to the left side. In accordance with this, the left first leg block 21 is shifted upward, and the right second leg block 22 is shifted downward.

  FIG. 5B shows an arrangement pattern of each block to be superimposed next to the arrangement shown in FIG. 5A (the stacking order is second, sixth, tenth,...). Therefore, each block is shifted in the opposite direction to the block of the arrangement pattern shown in FIG. That is, the second leg block 22 on the left side in the drawing, the first leg block 21 on the right side in the drawing, the second yoke block 24 on the upper side in the drawing, and the first yoke section on the lower side in the drawing. Block 23 is arranged. The upper second yoke part block 24 is shifted to the left side, and the lower first yoke part block 23 is shifted to the right side. In accordance with this, the left second leg block 22 is shifted downward, and the right first leg block 22 is shifted upward. Moreover, in order to comprise this arrangement pattern, the 2nd yoke part block 24 arrange | positioned, for example on the upper side, and the 1st yoke part block 23 arrange | positioned on the lower side are reversed and overlapped. Thereby, even if it shifts to right and left, the position of through-holes 23a and 24a corresponds. Thus, when each block is piled up, an iron core can be assembled using four types of blocks by inverting the front and back appropriately.

  Similarly, FIG. 5 (c) shows the arrangement pattern used for the third, seventh, eleventh, etc., in the stacking order, the second leg block 22 on the left side in the figure, and the first leg part on the right side in the figure. The block 21, the first yoke part block 23 on the upper side in the figure, and the second yoke part block 24 on the lower side in the figure are arranged. The upper first yoke part block 23 is shifted to the right side, and the lower second yoke part block 24 is shifted to the left side. In accordance with this, the left second leg block 22 is shifted upward, and the right first leg block 21 is shifted downward.

  Further, FIG. 5 (d) shows the arrangement pattern used for the fourth, eighth, twelfth, etc. in the stacking order, the first leg block 21 on the left side in the figure, and the second leg block on the right side in the figure. 22, the first yoke part block 23 is arranged on the upper side in the figure, and the second yoke part block 24 is arranged on the lower side in the figure. And the upper first yoke part block 23 is shifted to the left side, and the lower second yoke part block 24 is shifted to the right side. In accordance with this, the left second leg block 22 is shifted downward, and the right first leg block 21 is shifted upward.

  Then, when FIGS. 5A to 5D are stacked in the stacking order, the corresponding through holes are made to coincide with each other in the stacking direction. Therefore, in the arrangement patterns of FIGS. 5A and 5B, the vertical direction and the horizontal direction are the same. Also, the arrangement patterns in FIGS. 5C and 5D match in the vertical and horizontal directions. Then, the two blocks of the arrangement pattern of FIGS. 5A and 5B and the two blocks of the arrangement pattern of FIGS. 5C and 5D are shifted up and down. More specifically, the arrangement pattern blocks shown in FIGS. 5C and 5D are shifted upward by a predetermined distance B from the arrangement pattern blocks shown in FIGS. Therefore, the second yoke part block 24 forms a concave groove, and the first yoke part block 23 forms a ridge.

  And if a predetermined number of blocks are piled up, it inserts so that a volt | bolt may be penetrated in a through-hole, and it integrates by fastening a nut. At this time, a guide plate 19 is disposed on the front and rear surfaces of the plurality of stacked blocks (see FIG. 1), and the guide plate 19 is fastened together with bolts and nuts to form an iron core 11. The reason why the guide plate 19 is provided in this way is that the directional silicon steel plate constituting the block is thin and easily bent. And by pinching with the guide plate 19, it suppresses that the directional silicon steel plate concerned curves.

  In the above description, the first and second leg blocks 21 and 22 and the first and second yoke blocks 23 and 24, which constitute the same stacking order, are laminated and manufactured. For example, the yoke part 15 is formed first, and the first and second leg blocks 21 and 22 are appropriately attached to the leg part 14 to form the iron core. On the contrary, the leg portion 14 may be manufactured first.

(Modification)
In the first embodiment described above, the yoke portion 15 is provided with irregularities to increase the surface area and improve the cooling efficiency. However, the present invention is not limited to this, and irregularities are provided on the side surfaces of the leg portions 14. Also good. In the case where the yoke portion 15 is not provided with irregularities but only the leg portions 14 are provided with the irregularities, the assembly procedure shown in FIG. 5 described above is applied and the blocks in each stacking order are appropriately shifted to the left and right.

  Further, in the first embodiment described above, the first leg block 21 and the second leg block 22 constituting the leg part 14 are different in the outer dimensions and shapes although the formation positions of the through holes are different. The first yoke part block 23 and the second yoke part block 24 constituting the yoke part 15 are different in the formation position of the through holes, but the outer dimensions and shapes thereof are the same and are used when assembling. It was possible to improve the cooling efficiency of the iron core 11 by forming irregularities on the surface by a simple operation of shifting up and down. That is, it is possible to reduce the number and type of parts to be used by making the respective blocks used for the stacking positions for forming the ridges and the same blocks used for the stacking positions for forming the concave grooves. However, the present invention is not limited to this, and the block for forming the ridge and the block for forming the groove may be different. In this way, for example, irregularities are formed on the outer peripheral surface (for example, the first long sides 21b and 22b side) of the iron core 11 having a high heat dissipation effect, and the inner peripheral surface (for example, the second long sides 21c and 22c) of the iron core. The side) can be configured so as not to form unevenness, or unevenness can be formed on both the yoke portion 15 and the leg portion 14.

In the first embodiment and the modification, the self-cooling method using natural heat dissipation has been described as an example. However, one or a plurality of air-cooling fans / blowers are provided at appropriate positions to forcibly It is good to apply to the air-cooling type to cool. The cooling effect is further enhanced by the wind from the fan or the like striking against the iron core 11 or the mold coil 12 and cooling, and the ambient air warmed by the heat generated by the iron core 11 or the mold coil 12 is forcibly circulated and exhausted. In particular, a more preferable cooling effect can be achieved by providing wind from a fan / blower to a portion where the surface area is increased by providing irregularities such as the surface of the yoke portion 15.
These various modifications may be implemented in combination as appropriate, and may be applied to various embodiments described below.

  7 and 8 show the main configuration of the second embodiment of the present invention. In this embodiment, similarly to the first embodiment, a ridge 15a and a groove 15b are provided in the yoke portion 15 with a single-phase type mold transformer. In this embodiment, the slit 40 is formed in the middle of the iron core 11 in the overlapping direction. The slit 40 constitutes an air passage. Therefore, for example, a path is provided in which warm air existing in the inner space of the iron core 11 radiated and heated from the inner peripheral surface side of the letter-shaped iron core 11 passes through the slit 40 to the outside of the iron core 11. Moreover, by providing the slit 40, the heat inside the iron core 11 is also radiated through the slit 40, and the temperature of the entire iron core becomes uniform.

  Further, when the forced air cooling method is used, cooling air from the fan / blower hits the inside of the iron core 11 through the slit 40, and the cooling efficiency is improved. Further, for example, even if the installation position of the fan / blower is one side above or below the iron core 11, the wind from the fan / blower reaches the opposite side via the slit 40. Therefore, for example, the air from the fan / blower directly hits the unevenness formed on the lower surface of the lower yoke portion 15, and the upper surface of the lower yoke portion 15 (inside the inner space of the iron core), further upper Since the unevenness provided in the yoke portion 15 is hit by the wind moving through the slit 40, the cooling efficiency is improved.

  Furthermore, since the slit 40 is formed also in the leg part 14 which mounts the mold coil 12, the wind from a fan and an air blower moves the inside of the slit 40, and also hits the internal peripheral surface of the mold coil 12. FIG. Thus, the area where the mold coil is directly exposed to wind increases, and the cooling efficiency for the coil is improved.

  For example, as shown in FIG. 8, the slit 40 has spacers 43 mounted on the shafts of bolts 41 for fixing the blocks constituting the iron core 11, and between the heads of the bolts 41 and the spacers 43 and spacers. It may be formed by fastening the nut 42 in a state where a predetermined block is attached between the nut 43 and the nut 42 (attached to the screw portion at the tip of the bolt 41). By fastening the nut 42, the blocks are connected and integrated to form an iron core. At this time, in the section where the spacer 43 is interposed, a space is secured by the thickness of the spacer 43, and the slit 40 is formed. The Note that an auxiliary guide plate 44 is also interposed between the spacer 43 and the block for the same reason that the guide plate 19 is provided on the outer surface of the overlapped block. The auxiliary guide plate 44 may be made of the same material as the guide plate 19. However, if the thickness is too thick, the interval between the slits 40 becomes narrow (when the outer dimensions are constant), and therefore the thickness of the auxiliary guide plate 44 is preferably thinner than the thickness of the guide plate 19.

  In addition, since the other structure and effect are the same as 1st embodiment and the modification which were mentioned above, the detailed description is abbreviate | omitted. In the second embodiment, one spacer and one slit 40 are provided in the block stacking direction. However, the number of slits 40 may be set arbitrarily, and a plurality of slits 40 may be provided. As the number of installations increases, the cooling effect becomes higher, which is preferable. However, if the dimensions of the entire transformer are the same, the area through which the magnetic flux of the iron core passes becomes smaller.

  9-13 has shown the principal part of 3rd embodiment of this invention. In this embodiment, it is a three-phase type mold transformer. 9 shows a part of the iron core 11 constituting the molded transformer, FIG. 10 shows a front view of the iron core 11, FIG. 11 shows each block constituting the iron core 11, and FIG. 12 shows an assembling method of the iron core. FIG.

  As shown in FIG. 9, in this embodiment, no slit is provided as in the first embodiment, and the iron core 11 is configured by overlapping a plurality of blocks without gaps. And the iron core 11 which comprises the magnetic circuit of the mold transformer 10 of this embodiment is arrange | positioned up and down, a pair of yoke parts 15 extended in a horizontal direction, and a pair of left-right leg connected with the both ends of the yoke part 15 The center leg part 45 connected with the center of the part 14 and the yoke part 15 is provided. And although illustration is abbreviate | omitted, the mold coil is each mounted | worn to the leg part 14 on either side.

  Here, in the present embodiment, the left and right side surfaces of the leg portion 14 and the central leg portion 45 are repeatedly uneven along the thickness direction (the direction in which the directional silicon steel plates are laminated). That is, on the left and right side surfaces of the leg portion 14, ridges 14 a and concave grooves 14 b formed so as to extend in the vertical direction are alternately arranged in the thickness direction of the leg portion 14. Similarly, on the left and right side surfaces of the central leg 45, ridges 45 a and concave grooves 45 b formed so as to extend in the vertical direction are alternately arranged in the thickness direction of the central leg 45.

  By adopting such a configuration, the left and right side surfaces of the leg portion 14 and the central leg portion 45 are equivalent to the area of the front and rear surfaces of the ridges 14a and 45a protruding from the back surface of the concave grooves 14b and 45b compared to the conventional type in which the left and right sides are flat. The surface area, that is, the heat radiation area increases. Therefore, the cooling efficiency of the iron core 11 is increased, the generated heat of the iron core is efficiently radiated, and the cooling efficiency of the iron core is improved. Therefore, it is possible to reduce the size of the iron core and the molded transformer as a whole, and it is possible to increase the capacity of the transformer if the dimensions are the same.

  In this 3rd embodiment, although unevenness was formed in the side of leg 14 and center leg 45, you may form unevenness in yoke part 15 like each embodiment mentioned above. In addition, various modifications described above may be applied, such as adopting an air cooling method.

[Assembly method of iron core]
As described above, the iron core 11 of the present embodiment is a stacked iron core, and is formed by laminating many directional silicon steel plates having a predetermined shape. Therefore, a plurality of directional silicon steel sheets stacked together is used as one block, and ridges and grooves are alternately appeared in the stacking direction by alternately shifting left and right in units of blocks.

  A specific method of assembling the iron core 11 while alternately shifting up and down in units of blocks as described above is as follows. FIG. 11 shows each block formed by laminating a predetermined number of directional silicon steel plates for constituting the leg part 14, the central leg part 45, and the yoke part 15. FIG. 11A shows the third leg block 51, and FIG. 11B shows the fourth leg block 52. FIG. FIG. 11C shows the central leg block 53. FIG. 11D shows a third yoke part block 54, and FIG. 11E shows a fourth yoke part block 55. Each of the blocks 51 to 55 is configured by stacking a plurality of (for example, 12) strip-shaped directional silicon steel plates. Each directional silicon steel sheet has a basic shape of a planar shape of an isosceles trapezoid whose both ends in the longitudinal direction are inclined 45 degrees in the rolling direction.

  The third leg block 51 and the fourth leg block 52 have the same external dimensions, but are different in the formation positions of the guide through holes 51a and 52a. Specifically, both of the three through holes 51a and 52a are formed, and the through holes 51a and 52a are both arranged on the same straight line, and the arrangement pitch of the three through holes 51a and the arrangement of the three through holes 52a. Both pitches are the same interval, and are common in that they are shifted by a predetermined distance (C: 5 mm, for example) with respect to the longitudinal center of the block. The through hole 51a of the third leg block 51 is the center in the short direction. The through hole 52a of the fourth leg block 52 is shifted a predetermined distance (C / 2) upward from the center position in the lateral direction. The arrangement is shifted only by that. As a result, when the third leg block 51 and the fourth leg block 52 are overlapped so that the outer circumferences coincide with each other, the through hole 51a of the third leg block 51 and the fourth leg block 52 penetrate. The holes 52a have a positional relationship shifted by a distance C in the short direction. Therefore, when the blocks 51, 52 are overlapped so that the through hole 51a of the third leg block 51 and the through hole 52a of the fourth leg block 52 are opposed to and coincide with each other, the third leg block 51 The first long side 51b protrudes outward from the first long side 52b of the fourth leg block 52 by a distance C, and the second long side 51c of the third leg block 51 is the fourth leg block. The second long side 52c of 52 is protruded outwardly by a distance C from the second long side 52c.

  The central leg block 53 has a hexagonal shape in which a pair of vertices of an acute angle on a diagonal line of an elongated parallelogram are cut off. The central leg block 53 also has three through holes 53a arranged on the same straight line as the both leg block 51 and 52, and a predetermined distance (downward in the figure from the center position in the lateral direction). The arrangement is shifted by C / 2). The angle formed by the hypotenuse connecting the first long side 53b and the second long side 53c is 90 degrees, and the vertex 53d is shifted in the reverse direction by a predetermined distance C from the center position in the short direction. Therefore, two central leg blocks 53 are prepared, and when both blocks 53 are overlapped so that the through holes 53a face each other with the front and back inverted, the first of the central leg blocks 53 One long side 51b is in a state of projecting with a distance C shifted outward from the second long side 53c of the other central leg block 53.

  The third yoke portion block 54 and the fourth yoke portion block 55 have the same external dimensions, but are different in the formation positions of the guide through holes 54a and 55a. Specifically, it is arranged at the center position in the short direction, and the relative positional relationship between the four through holes (54a, 55a) in the pair is set equal, but the arrangement position in the longitudinal direction is shifted. Yes. The center position of the four through holes 54a of the third yoke part block 54 is a predetermined distance D (for example, 7.5 mm) to the right in the drawing with respect to the center position of the third yoke part block 54 in the longitudinal direction. Shift and arrange. The center position of the four through holes 55a of the fourth yoke part block 55 is a predetermined distance (D-C) (for example, to the right in the figure with respect to the center position in the longitudinal direction of the fourth yoke part block 55). 2.5 mm) and dispose. Thereby, the through holes 54a and 55a provided in both the blocks 54 and 55 are in a positional relationship shifted by a distance C in the longitudinal direction of the blocks. Therefore, if both the blocks 54 and 55 are overlapped so that the through hole 54a of the third yoke part block 54 and the through hole 55a of the fourth yoke part block 55 face each other, the third yoke part The block 54 and the fourth yoke block 55 are in a state in which the first long sides 54b and 55b and the second long sides 54c and 55c overlap each other, and both oblique sides in the longitudinal direction are shifted by a distance C. Become.

  Further, in the present embodiment, a triangular cut portion 54d is provided at the center of the second long sides 54c and 55c of the third yoke portion block 54 and the fourth yoke portion block 55. The vertex 53d of the center leg block 53 enters the cut portion 54d.

  Specifically, the blocks are arranged and stacked in the product order shown in FIGS. 12 (a) and 12 (b). That is, as in each embodiment, the third and fourth yoke part blocks 54 and 55 are alternately shifted by a predetermined distance X in the longitudinal direction when stacked. In the present embodiment, the distance X is equal to the distance C shifted left and right, but may be different. By displacing in this way in the longitudinal direction, the yoke blocks 54 and 55 alternately have their one ends protruding sideways by a predetermined distance X. In accordance with this, the third and fourth leg blocks 51 and 52 are also laminated while being shifted by a predetermined distance X alternately in the longitudinal direction. At this time, the adjacent yoke block and leg block are reversed in direction, and the protruding tip of each block enters the other party's retracted space.

  Further, in the present embodiment, the shifting directions of the two yoke block at the same product position are also reversed. Similarly, the shifting directions of two leg blocks in the same product position are also reversed. Furthermore, the positions of the cut portions 54d are alternately shifted left and right as the yoke blocks 54 and 55 are shifted to the left and right. Therefore, the center leg block 53 sets the vertices 53d at both ends in the longitudinal direction to the cut portions 54d and 55d while reversing the front and back.

  Therefore, the arrangement order of each block in the stacking order shown in FIG. 12 (a) is first, third, fifth ... and the stacking order shown in FIG. 12 (b) is second, fourth, sixth ... When the block arrangement patterns are alternately stacked, the leg blocks located on the left and right are alternately arranged so that the positions are shifted left and right, so that the ridges 14a and the grooves 14b are repeatedly formed in the stacking direction. . Moreover, the center leg part is formed with the ridges 45a and the grooves 45b repeatedly in the stacking direction by inverting the front and back.

  Also in this embodiment, both a self-cooling type and an air-cooling type can be adopted. In particular, when the air-cooling type is employed and the fan / blower is disposed above and / or below the iron core 11, the wind from the fan / blower flows along the concave groove 45b, which is preferable because the cooling efficiency is further improved. Since other configurations and operational effects are the same as those of the various embodiments and modifications described above, detailed description thereof is omitted.

  FIG. 13 shows the main part of the fourth embodiment of the present invention. In this embodiment, it is a three-phase type mold transformer, and also in this embodiment, protrusions 14a and 45a and grooves 14b and 45b are provided on the left and right side surfaces of the leg portion 14 and the center leg portion 45, respectively.

  And in this embodiment, the slit 40 is provided in the predetermined position of the lamination direction of a block similarly to 2nd embodiment. In particular, since the internal space of the iron core 11 is connected to the outside by providing the slit 40, heat is efficiently radiated by the unevenness formed on both side surfaces of the central leg 45, and the heat is radiated to the outside through the slit 40. Good.

  Particularly, forced air cooling is preferable because heat from the central leg 45 can be radiated to the external space of the iron core 11 through the slit 40. The slit 40 can be formed in the same manner as in the second embodiment. Since other configurations and operational effects are the same as those of the various embodiments and modifications described above, detailed description thereof is omitted.

DESCRIPTION OF SYMBOLS 10 Mold transformer 11 Iron core 12 Mold coil 14 Leg part 14a Projection 14b Groove 15 Relay part 15a Projection 15b Groove 40 Slit 45 Center leg 45a Projection 45b Groove

Claims (7)

At least both ends of a yoke part made of a pair of magnetic bodies are connected by leg parts made of a magnetic substance, and the yoke part and the leg parts alternately have a plurality of strip-like blocks in the longitudinal direction. While laminating while shifting, the iron core whose joint is inclined,
A molded coil attached to the leg,
A molded transformer comprising:
The surface shape of the outer peripheral surface of the yoke part is uneven in the direction in which the blocks are laminated,
The unevenness is composed of a first part, a second part protruding outward from the first part, and a third part lowered inward from the first part,
The mold transformer characterized in that the outer peripheral surface and the inner peripheral surface of the leg portion have flat surfaces in the direction in which the blocks are stacked. At least both ends of a yoke part made of a pair of magnetic bodies are connected by leg parts made of a magnetic substance, and the yoke part and the leg parts alternately have a plurality of strip-like blocks in the longitudinal direction. While laminating while shifting, the iron core whose joint is inclined,
A molded coil attached to the leg,
A molded transformer comprising:
The surface shape of both the outer peripheral surface of the yoke part and the outer peripheral surface of the leg part is uneven in the direction in which the blocks are laminated ,
The unevenness is configured in three stages of a first part, a second part protruding outward from the first part, and a third part falling inward from the first part. Mold transformer.   The mold transformer according to claim 1, wherein the unevenness has a fin structure in which concave grooves and convex stripes are repeatedly arranged. Comprising a central leg connecting the intermediate parts of the yoke part;
4. The molded transformer according to claim 1, wherein a surface shape of a side surface of the central leg portion is uneven in a direction in which the blocks are stacked. 5.   The molded transformer according to any one of claims 1 to 4, wherein a slit is formed with a gap at least at one place between the blocks to be laminated.   The molded transformer according to any one of claims 1 to 5, wherein a blowing means is disposed outside the iron core to form a forced air cooling type. An assembly method of an iron core used for the molded transformer according to any one of claims 1 to 6,
The yoke part block for constituting the yoke part and the leg block for constituting the leg part are in the form of strips and the joints at both ends are inclined,
The yoke part block and the leg block are stacked while being alternately shifted in the longitudinal direction, the yoke part block for constituting the yoke part, and the leg part for constituting the leg part. One of the blocks is alternately shifted in the short side direction as well as the long side direction to form the irregularities shifted in the three steps .

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