Transformers

Abstract

To suppress the deformation of a return leg of an iron core that constitutes a transformer.SOLUTION: A transformer 10 includes a core 20 including a main leg 23a and a return leg 23b, a resin molded coil 10 surrounding the main leg 23a, and a flat insulating plate 50 installed between the outer peripheral surface of the resin molded coil 10 and the inner surface 61 of the return leg 23b along the inner surface 61 of the return leg 23b.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a transformer. [Background technology]

[0002] Various types of transformers having an iron core that constitutes a magnetic circuit and a coil that constitutes an electric circuit have been proposed. For example, Patent Document 1 discloses a transformer having a structure in which each leg of an iron core is surrounded by a resin-molded coil in which the coil is molded with an insulating resin material. Patent Document 2 discloses a transformer in which two return legs corresponding to the return path of the magnetic circuit are installed on both sides of three main legs around which coils are wound among the multiple legs that constitute the iron core. The iron core of the transformer is formed by stacking or winding metal layers such as electromagnetic steel sheets in multiple layers. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-029505 A [Patent Document 2] JP 2002-025834 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a conventional transformer in which the core includes a return leg, deformation of the return leg is a problem. For example, the inner surface of the return leg may be locally wavy due to the weight of the core. When the return leg is deformed toward the resin molded coil, the distance between the inner surface of the return leg and the outer peripheral surface of the resin molded coil may not be sufficiently secured. In addition, a gap may occur between the metal layers constituting the core, resulting in a situation in which the thickness of the return leg locally exceeds the design value. In consideration of the above circumstances, one aspect of the present invention aims to suppress deformation of the return leg of the iron core constituting the transformer. [Means for solving the problem]

[0005] A transformer according to a preferred embodiment of the present invention comprises an iron core including a main leg and a return leg, a resin molded coil surrounding the main leg, and a flat insulating plate installed between the outer peripheral surface of the resin molded coil and the inner surface of the return leg and conforming to the inner surface of the return leg. Effect of the Invention

[0006] According to the present invention, deformation of the return leg of the iron core that constitutes the transformer can be suppressed. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a front view of the transformer according to the first embodiment. [Diagram 2] 2A and 2B are a front view and a cross-sectional view of a resin molded coil and an iron core in a transformer. [Diagram 3] FIG. 2 is an enlarged front view of the transformer near an insulating plate. [Figure 4] FIG. 4 is a cross-sectional view taken along the line BB in FIG. [Diagram 5] FIG. 11 is an enlarged front view of the vicinity of an insulating plate in a transformer according to a second embodiment. [Figure 6] 6 is a cross-sectional view taken along the line CC in FIG. 5. [Figure 7] FIG. 11 is a front view of a transformer according to a third embodiment. [Figure 8] FIG. 11 is a cross-sectional view of a transformer according to a modified example. [Figure 9] FIG. 11 is a cross-sectional view of a transformer according to a modified example. [Figure 10] FIG. 13 is a front view of a transformer according to a modified example. [Figure 11] FIG. 13 is a front view of a transformer according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The embodiments for carrying out the present invention will be described with reference to the drawings. Note that in each drawing, the dimensions and scale of each element may differ from those of the actual product. In addition, the embodiments described below are specific examples assumed when carrying out the present invention, and therefore the scope of the present invention is not limited to the following embodiments.

[0009] A: First embodiment Fig. 1 is a front view of a transformer 100 according to a first embodiment of the present invention. As illustrated in Fig. 1, in the following description, for the sake of convenience, an X-axis, a Y-axis, and a Z-axis are assumed to be mutually orthogonal. A plane including the X-axis and the Y-axis corresponds to a horizontal plane, and the direction of the Z-axis corresponds to a vertical direction.

[0010] The transformer 100 of the first embodiment is a power device that converts AC voltage by utilizing electromagnetic induction. As illustrated in Fig. 1, the transformer 100 includes three resin molded coils 10, an iron core 20, a support frame 30, an installation stand 40, and two insulating plates 50. The three resin molded coils 10 form an electric circuit of the transformer 100, and the iron core 20 forms a magnetic circuit of the transformer 100. In Fig. 1, the insulating plate 50 is hatched for convenience.

[0011] FIG. 2 shows a front view and a cross-sectional view focusing on the resin molded coil 10, the iron core 20, and the insulating plate 50 for the sake of convenience. The cross-sectional view in FIG. 2 is a cross-sectional view taken along the line AA in the front view in FIG. 2. The three resin molded coils 10 are arranged in the direction of the X-axis. Each of the three resin molded coils 10 is a cylindrical structure in which the coil is molded using an insulating resin material, and is installed so that its central axis is aligned with the Z-axis. In other words, the direction of the Z-axis corresponds to the axial direction of the resin molded coil 10. The coils of each resin molded coil 10 are connected to each other by wiring (not shown).

[0012] As illustrated in the cross-sectional view of FIG. 2, each resin molded coil 10 of the first embodiment includes a high-voltage molded coil 11 and a low-voltage molded coil 12. Each of the high-voltage molded coil 11 and the low-voltage molded coil 12 includes a coil formed in a cylindrical shape from a conductive material and a resin mold that contains the coil. The high-voltage molded coil 11 surrounds the low-voltage molded coil 12. Specifically, the inner peripheral surface of the high-voltage molded coil 11 and the outer peripheral surface of the low-voltage molded coil 12 face each other with a gap between them. A higher voltage is applied to the coil of the high-voltage molded coil 11 than to the coil of the low-voltage molded coil 12. Note that the resin molded coil 10 may be formed of a single coil.

[0013] The iron core 20 constitutes the magnetic circuit of the transformer 100. The iron core 20 is a structure in which metal layers such as electromagnetic steel sheets or amorphous alloy ribbons are laminated or wound in multiple layers, and is composed of four rectangular ring-shaped parts connected to each other in the X-axis direction. The iron core 20 of the first embodiment has a first yoke part 21, a second yoke part 22, and five legs 23. Each leg 23 is a columnar part extending in the Z-axis direction. The five legs 23 are installed at intervals in the X-axis direction. The first yoke part 21 and the second yoke part 22 extend in the X-axis direction. The first yoke part 21 is a part that connects the upper ends of the five legs 23 to each other, and the second yoke part 22 is a part that connects the lower ends of the five legs 23 to each other. As can be understood from the above description, the transformer 100 of the first embodiment is a three-phase five-leg iron core transformer.

[0014] The five legs 23 include three main legs 23a and two return legs 23b. The three main legs 23a are located between the two return legs 23b. Each of the three resin molded coils 10 surrounds one of the three main legs 23a of the iron core 20 that corresponds to the resin molded coil 10. That is, each main leg 23a is a leg 23 surrounded by the resin molded coil 10 among the multiple legs 23. On the other hand, the return leg 23b is a leg 23 (i.e., a side leg) that functions as a return leg of the magnetic circuit among the multiple legs 23 of the iron core 20. As can be understood from the above description, the iron core 20 of the first embodiment includes the main legs 23a and the return legs 23b. As illustrated in FIG. 2, the three resin molded coils 10 are arranged in the X-axis direction between the two return legs 23b.

[0015] The support frame 30 in FIG. 1 supports three resin molded coils 10, an iron core 20, and two insulating plates 50. The support frame 30 in the first embodiment is a rectangular frame-shaped structure including a first support 31, a second support 32, and two side supports 33. The first support 31 and the second support 32 are members extending in the X-axis direction. The first support 31 supports the first yoke portion 21 of the iron core 20. The second support 32 supports the second yoke portion 22 of the iron core 20. The two side supports 33 are structures extending in the Z-axis direction. Specifically, each side support 33 connects the respective ends of the first support 31 and the second support 32 to each other. The installation base 40 is a base that supports the support frame 30.

[0016] A plurality of spacers 35 are interposed between the lower surface of the first support 31 and the upper surfaces 10a of the three resin molded coils 10. The upper surface 10a of the resin molded coil 10 is an end surface of the resin molded coil 10 located in the negative direction of the Z axis. On the other hand, a plurality of spacers 36 are interposed between the upper surface of the second support 32 and the lower surfaces 10b of the three resin molded coils 10. The lower surfaces 10b of the resin molded coil 10 are end surfaces of the resin molded coil 10 located in the positive direction of the Z axis. As can be understood from the above description, the three resin molded coils 10 are supported between the first support 31 and the second support 32. In FIG. 1, the spacers 35 and the spacers 36 are shaded for convenience.

[0017] FIG. 3 is an enlarged front view of the vicinity of the right insulating plate 50 in FIG. 2 among the two insulating plates 50, and FIG. 4 is a cross-sectional view of the line BB in FIG. 3. FIG. 3 illustrates the right resin molded coil 10 among the three resin molded coils 10, the right return leg 23b among the two return legs 23b, and the right side support 33 among the two side supports 33. A part of the side support 33 is cut away in FIG. 3 for convenience. Also, the illustration of the spacer 35 and the spacer 36 is omitted in FIG. 3 for convenience. Note that the structure of the elements (resin molded coil 10, return leg 23b, and insulating plate 50) located on the left side of the transformer 100 is a structure in which the left and right are reversed in FIG. 3 and FIG. 4, and therefore detailed description will be omitted below.

[0018] As illustrated in FIG. 4, the return leg 23b is a rectangular column including an inner surface 61, an outer surface 62, a front surface 63, and a rear surface 64. The inner surface 61 is a wall surface facing the inside of the iron core 20, and the outer surface 62 is a wall surface opposite to the inner surface 61. The inner surface 61 and the outer surface 62 of the return leg 23b are flat surfaces parallel to the YZ plane. The direction of the Y axis (an example of a first direction) is a direction parallel to the inner surface 61 or the outer surface 62 of the return leg 23b and perpendicular to the axial direction (the direction of the Z axis) of the resin molded coil 10. Each of the front surface 63 and the rear surface 64 is a wall surface that connects the inner surface 61 and the outer surface 62 to each other. Specifically, the front surface 63 and the rear surface 64 are flat surfaces parallel to the XZ plane.

[0019] The side support 33 is a structure including a base portion 331, a side portion 332, and a side portion 333. Each of the base portion 331, the side portion 332, and the side portion 333 is a flat portion extending in the direction of the Z axis. The side portion 332 is continuous with one long side of the base portion 331, and the side portion 333 is continuous with the other long side of the base portion 331. The side portion 332 and the side portion 333 protrude from each edge of the base portion 331 in the negative direction of the X axis. In other words, the side portion 332 and the side portion 333 face each other with a gap between them in the direction of the Y axis.

[0020] The return legs 23b are supported by the side supports 33. Specifically, the outer surfaces 62 of the return legs 23b contact the inner surfaces of the base portions 331 of the side supports 33. That is, the side supports 33 support the iron core 20 while contacting the outer surfaces 62 of the return legs 23b. The side supports 33 are an example of a "support." The entire support frame 30 may be interpreted as a "support."

[0021] The length of return leg 23b in the direction of the Y axis is less than the length of resin molded coil 10 in the direction of the Y axis. As illustrated in FIG. 4, inner surface 61 of return leg 23b faces the outer peripheral surface of high-voltage molded coil 11 with a gap therebetween. An area 13 of high-voltage molded coil 11 facing inner surface 61 of return leg 23b (hereinafter referred to as "facing surface") is a flat surface parallel to inner surface 61. As can be understood from the above explanation, a space of a predetermined distance is formed between facing surface 13 of high-voltage molded coil 11 and inner surface 61 of return leg 23b. The outer peripheral surface of high-voltage molded coil 11 can also be referred to as the outer peripheral surface (facing surface 13) of resin molded coil 10.

[0022] The insulating plate 50 is a rectangular plate-like member formed to a constant thickness over the entire area. Specifically, the insulating plate 50 is a laminated plate formed of an insulating resin material such as phenolic resin or glass epoxy, and includes a first surface 51 and a second surface 52. The first surface 51 is one of the plate surfaces of the insulating plate 50, and the second surface 52 is the plate surface opposite to the first surface 51.

[0023] As illustrated in FIG. 3 and FIG. 4, the insulating plate 50 is installed between the opposing surface 13 of the resin molded coil 10 and the inner surface 61 of the return leg 23b. Specifically, the first surface 51 of the insulating plate 50 is in close contact with the opposing surface 13 of the resin molded coil 10, and the second surface 52 of the insulating plate 50 is in close contact with the inner surface 61 of the return leg 23b. That is, the insulating plate 50 is installed along the opposing surface 13 of the resin molded coil 10 and the inner surface 61 of the return leg 23b. The side support 33 presses the outer surface 62 of the return leg 23b toward the insulating plate 50. That is, the side support 33 supports the return leg 23b in a state in which the return leg 23b is pressed against the second surface 52 of the insulating plate 50. The first surface 51 of the insulating plate 50 is bonded to the opposing surface 13 of the resin molded coil 10 by, for example, an adhesive. On the other hand, the second surface 52 of the insulating plate 50 is not bonded to the inner surface 61 of the return leg 23b. According to the above configuration, when one of the resin molded coil 10 and the return leg 23b moves in a direction parallel to the YZ plane relative to the other, the insulating plate 50 slides against the return leg 23b. Therefore, the possibility that the insulating plate 50 peels off from the resin molded coil 10 is reduced. Note that a configuration in which the second surface 52 of the insulating plate 50 is bonded to the inner surface 61 of the return leg 23b and the first surface 51 is not bonded to the opposing surface 13 of the resin molded coil 10, or a configuration in which the insulating plate 50 is bonded to both the resin molded coil 10 and the return leg 23b, is also assumed.

[0024] As illustrated in Fig. 3, the position and range of the insulating plate 50 in the direction of the Z axis will be described with reference to the upper surface 53 and the lower surface 54 of the insulating plate 50. As illustrated in Fig. 3, the upper surface 53 of the insulating plate 50 is an end surface of the insulating plate 50 located in the negative direction of the Z axis, and is a flat surface parallel to the XY plane. The lower surface 54 of the insulating plate 50 is an end surface of the insulating plate 50 located in the positive direction of the Z axis, and is a flat surface parallel to the XY plane.

[0025] The insulating plate 50 spans the upper surface 10a and the lower surface 10b of the resin molded coil 10 in the Z-axis direction. Specifically, the upper surface 53 of the insulating plate 50 and the upper surface 10a of the resin molded coil 10 are located in the same plane (so-called flush). That is, the upper surface 53 of the insulating plate 50 and the upper surface 10a of the resin molded coil 10 are continuous with each other without any steps. Similarly, the lower surface 54 of the insulating plate 50 and the lower surface 10b of the resin molded coil 10 are located in the same plane. That is, the lower surface 54 of the insulating plate 50 and the lower surface 10b of the resin molded coil 10 are continuous with each other without any steps.

[0026] Next, as illustrated in Fig. 4, the position and range of insulating plate 50 in the direction of the Y axis will be described with reference to side surface 55 and side surface 56 of insulating plate 50. As illustrated in Fig. 4, side surface 55 of insulating plate 50 is a side surface of insulating plate 50 located in the positive direction of the Y axis, and side surface 56 of insulating plate 50 is a side surface of insulating plate 50 located in the negative direction of the Y axis. Side surface 55 and side surface 56 are flat surfaces parallel to the XZ plane.

[0027] The side 55 and the side 56 of the insulating plate 50 are located outside the inner surface 61 of the return leg 23b in the direction of the Y axis. That is, the side 55 is located in the positive direction of the Y axis from the front surface 63 of the return leg 23b, and the side 56 is located in the negative direction of the Y axis from the back surface 64 of the return leg 23b. It may be expressed that the insulating plate 50 protrudes in the positive direction of the Y axis from the front surface 63 of the return leg 23b, and the insulating plate 50 protrudes in the negative direction of the Y axis from the back surface 64 of the return leg 23b. As can be understood from the above description, the insulating plate 50 is interposed between the corner C of the return leg 23b on the resin molded coil 10 side and the opposing surface 13 of the resin molded coil 10. The corner C of the return leg 23b is an angular corner formed by the inner surface 61 of the return leg 23b and the front surface 63 or the back surface 64. Moreover, the insulating plate 50 is located within the range between the outer surfaces of the side surface portions 332 and 333 of the side support 33 in the Y-axis direction.

[0028] As can be understood from the above description, in the first embodiment, a flat insulating plate 50 is placed between the opposing surface 13 of the resin molded coil 10 and the inner surface 61 of the return leg 23b. Therefore, as exemplified below, the inner surface 61 of the return leg 23b comes into contact with the second surface 52 of the insulating plate 50, thereby suppressing deformation of the return leg 23b.

[0029] In a configuration in which the insulating plate 50 is not provided (hereinafter referred to as "comparative example"), for example, localized waving may occur on the inner surface 61 of the return leg 23b due to the weight of the core 20. At the crest of the waving occurring on the inner surface 61 of the return leg 23b, the distance between the opposing surface 13 of the resin molded coil 10 and the inner surface 61 of the return leg 23b may fall below the design value. According to the first embodiment, the inner surface 61 of the return leg 23b comes into contact with the insulating plate 50, suppressing the waving on the inner surface 61, so that the distance (insulation distance) between the resin molded coil 10 and the return leg 23b can be sufficiently secured. In addition, in the process of inserting each main leg 23a of the core 20 into each resin molded coil 10 in the manufacturing process of the transformer 100, the inner surface 61 of the return leg 23b slides along the second surface 52 of the insulating plate 50. That is, the insulating plate 50 functions as a guide for guiding the return leg 23b. Therefore, it is possible to assemble the resin molded coil 10 and the return leg 23b with high precision.

[0030] In the comparative example, the thickness of the return leg 23b (the distance between the inner surface 61 and the outer surface 62) may increase from the design value due to the occurrence of gaps between the metal layers constituting the iron core 20. According to the first embodiment, the return leg 23b is compressed in the X-axis direction by being sandwiched between the side support 33 and the insulating plate 50, so that the increase in the thickness of the return leg 23b, which is a problem in the comparative example, is suppressed. As a result of suppressing the increase in the thickness of the return leg 23b, there is also the advantage that the transformer 100 is made smaller.

[0031] In the first embodiment, an insulating plate 50 is interposed between the resin molded coil 10 and the return leg 23b. Therefore, compared to a configuration in which the opposing surface 13 of the resin molded coil 10 and the inner surface 61 of the return leg 23b are spaced apart from each other, heat generated in the resin molded coil 10 is more likely to be conducted to the return leg 23b via the insulating plate 50. Since the return leg 23b is not surrounded by the resin molded coil 10, the heat conducted via the insulating plate 50 is effectively dissipated from the return leg 23b. As described above, according to the first embodiment, the heat generated in the transformer 100 can be effectively dissipated. In particular, in the first embodiment, the insulating plate 50 contacts the opposing surface 13 of the high-voltage molded coil 11. Since the high-voltage molded coil 11 is more likely to generate heat than the low-voltage molded coil 12, the first embodiment in which heat conduction via the insulating plate 50 is more likely to occur is particularly effective.

[0032] In the first embodiment, the side 55 and the side 56 of the insulating plate 50 are located outside the inner surface 61 of the return leg 23b in the Y-axis direction. That is, the insulating plate 50 is interposed between the corner C formed on the periphery of the inner surface 61 of the return leg 23b and the resin molded coil 10. According to the above configuration, the insulating plate 50 realizes the effect of ensuring electrical insulation between the corner C of the return leg 23b and the outer circumferential surface of the resin molded coil 10 (hereinafter referred to as the "insulating barrier effect"). In the first embodiment, in particular, the insulating plate 50 extends in the Z-axis direction across the upper surface 10a and the lower surface 10b of the resin molded coil 10 (i.e., across the entire length of the opposing surface 13). Therefore, compared with a configuration in which the insulating plate 50 locally faces only a part of the opposing surface 13 of the resin molded coil 10 in the Z-axis direction (i.e., a configuration in which the entire length of the insulating plate 50 is shorter than the entire length of the resin molded coil 10), the insulating barrier effect of the insulating plate 50 can be sufficiently ensured.

[0033] B: Second embodiment The second embodiment will be described below. Note that, in the configurations exemplified below, for elements whose functions are similar to those of the first embodiment, the reference numerals used in the description of the first embodiment will be used and detailed descriptions of each will be omitted as appropriate.

[0034] Fig. 5 is an enlarged front view of the insulating plate 50 and its vicinity in the transformer 100 of the second embodiment, and Fig. 6 is a cross-sectional view of the line CC in Fig. 5. Fig. 5 corresponds to Fig. 3 of the first embodiment, and Fig. 6 corresponds to Fig. 4 of the first embodiment. As illustrated in Fig. 5 and Fig. 6, the transformer 100 of the second embodiment includes a deformable sheet 70 in addition to the same elements as those in the first embodiment.

[0035] The deformable sheet 70 is a sheet-like or flat plate-like structure that is more flexible than the insulating plate 50. That is, the surface of the deformable sheet 70 is deformed, for example, by pressure from the outside. The deformable sheet 70 includes a first surface 71 and a second surface 72. The first surface 71 is one of the plate surfaces of the deformable sheet 70, and the second surface 72 is the plate surface opposite the first surface 71. The deformable sheet 70 is formed to a constant thickness (for example, about 2 mm) over the entire area. The thickness of the deformable sheet 70 is less than that of the insulating plate 50. The deformable sheet 70 is formed of various insulating materials such as rubber. For example, a rubber sheet capable of elastic deformation is used as the deformable sheet 70.

[0036] The deformation sheet 70 is placed between the opposing surface 13 of the resin molded coil 10 and the first surface 51 of the insulating plate 50. Specifically, the first surface 71 of the deformation sheet 70 is in close contact with the opposing surface 13 of the resin molded coil 10, and the second surface 72 of the deformation sheet 70 is in close contact with the first surface 51 of the insulating plate 50. That is, the deformation sheet 70 is placed along the opposing surface 13 of the resin molded coil 10 and the inner surface 61 of the return leg 23b. The first surface 71 of the deformation sheet 70 is bonded to the opposing surface 13 of the resin molded coil 10 by, for example, an adhesive. In addition, the second surface 72 of the deformation sheet 70 is bonded to the first surface 51 of the insulating plate 50 by, for example, an adhesive. On the other hand, the second surface 52 of the insulating plate 50 is not bonded to the inner surface 61 of the return leg 23b, as in the first embodiment. According to the above configuration, when one of the resin molded coil 10 and the return leg 23b moves in a direction parallel to the YZ plane relative to the other, the insulating plate 50 slides against the return leg 23b, reducing the possibility of peeling off of the deformable sheet 70. Note that a configuration in which the first surface 71 of the deformable sheet 70 is not bonded to the opposing surface 13 of the resin molded coil 10, or a configuration in which the second surface 72 of the deformable sheet 70 is not bonded to the insulating plate 50 is also assumed. For example, a configuration in which the second surface 52 of the insulating plate 50 is bonded to the inner surface 61 of the return leg 23b, the second surface 72 of the deformable sheet 70 is bonded to the insulating plate 50, and the first surface 71 of the deformable sheet 70 is not bonded to the opposing surface 13 of the resin molded coil 10 is also assumed.

[0037] The deformable sheet 70 is formed in a shape (e.g., rectangular) and dimensions equivalent to those of the insulating plate 50 in a plan view so as to overlap the entire area of ​​the insulating plate 50. Therefore, the deformable sheet 70 extends across the upper surface 10a and the lower surface 10b of the resin molded coil 10 in the Z-axis direction. In addition, as illustrated in Fig. 6, the side surface of the deformable sheet 70 is located outside the inner surface 61 of the return leg 23b in the Y-axis direction.

[0038] The second embodiment also achieves the same effect as the first embodiment. Meanwhile, the opposing surface 13 of the resin molded coil 10 or the first surface 51 of the insulating plate 50 may have irregularities due to, for example, manufacturing errors. In the first embodiment in which the deformable sheet 70 is not provided, the pressure acting between the opposing surface 13 of the resin molded coil 10 and the first surface 51 of the insulating plate 50 may be distributed unevenly depending on the irregularities of the opposing surface 13 or the first surface 51. For example, there are cases where a local pressure acts on the first surface 51 due to a convex portion of the opposing surface 13, or where a local pressure acts on the opposing surface 13 due to a convex portion of the first surface 51.

[0039] According to the second embodiment, the first surface 71 of the deformable sheet 70 deforms in response to the unevenness of the opposing surface 13 of the resin molded coil 10, and the second surface 72 of the deformable sheet 70 deforms in response to the unevenness of the first surface 51 of the insulating plate 50. Therefore, there is an advantage that the pressure acting between the opposing surface 13 of the resin molded coil 10 and the first surface 51 of the insulating plate 50 is uniformed within the surface of the deformable sheet 70. In particular, in the second embodiment, since the deformable sheet 70 overlaps the entire insulating plate 50, the above-mentioned effect of uniforming the pressure is particularly remarkable. On the other hand, according to the first embodiment, since the deformable sheet 70 is not installed, there is an advantage that the manufacturing cost of the transformer 100 is reduced compared to the second embodiment. Therefore, when the unevenness of the pressure between the resin molded coil 10 and the insulating plate 50 is not a particular problem, the first embodiment is advantageous in terms of manufacturing costs.

[0040] C: Third embodiment FIG. 7 is a front view illustrating the configuration of a transformer 100 in the third embodiment. In the first embodiment, a three-phase five-legged core transformer having three resin molded coils 10 is illustrated. The transformer 100 in the third embodiment is a single-phase three-legged core transformer having one resin molded coil 10. That is, the core 20 in the transformer 100 in the third embodiment has three legs 23 including one main leg 23a and two return legs 23b. The configuration in which an insulating plate 50 is installed between each return leg 23b and the resin molded coil 10 is the same as in the first embodiment. The configuration related to the insulating plate 50 is also the same as in the first embodiment. Therefore, the third embodiment also achieves the same effects as the first embodiment.

[0041] As can be understood from the above examples, the number of main legs 23a and return legs 23b included in the iron core 20 of the transformer 100, or the number of resin molded coils 10 is arbitrary. Moreover, the configuration of the second embodiment in which the deformable sheet 70 is provided between the resin molded coil 10 and the insulating plate 50 is similarly applied to the transformer 100 of the third embodiment.

[0042] D: Variation Specific modified embodiments added to each of the above-mentioned embodiments are exemplified below. Two or more embodiments selected from the following examples may be appropriately combined as long as they are not mutually contradictory.

[0043] (1) In each of the above-described embodiments, a configuration has been illustrated in which side 55 and side 56 of insulating plate 50 are positioned outside inner surface 61 of return leg 23b in the Y-axis direction, but the relationship between insulating plate 50 and return leg 23b is not limited to the above examples.

[0044] For example, as illustrated in FIG. 8, a configuration is also envisaged in which the side 55 and the side 56 of the insulating plate 50 are located inside the inner surface 61 of the return leg 23b in the direction of the Y axis. In the configuration of FIG. 8, the side 55 of the insulating plate 50 is located in the negative direction of the Y axis from the front surface 63 of the return leg 23b, and the side 56 of the insulating plate 50 is located in the positive direction of the Y axis from the back surface 64 of the return leg 23b. The deformable sheet 70 is formed in a shape and dimensions equivalent to those of the insulating plate 50 in a plan view so as to overlap the entire area of ​​the insulating plate 50. According to the above configuration, the size of the insulating plate 50 is reduced compared to the first embodiment. Therefore, there is an advantage in that the manufacturing cost of the transformer 100 is reduced.

[0045] In each of the above-described embodiments, the insulating plate 50 is located within the range between the outer surface of the side surface portion 332 and the outer surface of the side surface portion 333 of the side support 33 in the Y-axis direction. However, as illustrated in FIG. 9, a configuration in which the insulating plate 50 extends in the Y-axis direction to the outside of the range between the outer surface of the side surface portion 332 and the outer surface of the side surface portion 333 of the side support 33 is also assumed. In the configuration of FIG. 9, the side surface 55 of the insulating plate 50 is located in the positive direction of the Y-axis from the outer surface of the side surface portion 332, and the side surface 56 of the insulating plate 50 is located in the negative direction of the Y-axis from the outer surface of the side surface portion 333. The deformable sheet 70 is formed in a shape and dimensions equivalent to those of the insulating plate 50 in a plan view so as to overlap the entire area of ​​the insulating plate 50. According to the configuration of FIG. 9, the insulating barrier effect of the insulating plate 50 described in the first embodiment can be sufficiently ensured. Note that the deformable sheet 70 may be omitted in the configurations illustrated in FIG. 8 and FIG. 9.

[0046] (2) In each of the above-described embodiments, the upper surface 53 of the insulating plate 50 and the upper surface 10a of the resin molded coil 10 are located in the same plane, and the lower surface 54 of the insulating plate 50 and the lower surface 10b of the resin molded coil 10 are located in the same plane. However, the relationship between the upper surface 53 of the insulating plate 50 and the upper surface 10a of the resin molded coil 10, and the relationship between the lower surface 54 of the insulating plate 50 and the lower surface 10b of the resin molded coil 10 are not limited to the above examples.

[0047] For example, as illustrated in Fig. 10, a configuration in which the insulating plate 50 protrudes in the Z-axis direction from the upper surface 10a and the lower surface 10b of the resin molded coil 10 is also assumed. In the configuration of Fig. 10, the upper surface 53 of the insulating plate 50 is located in the negative direction of the Z-axis from the upper surface 10a of the resin molded coil 10, and the lower surface 54 of the insulating plate 50 is located in the positive direction of the Z-axis from the lower surface 10b of the resin molded coil 10. The deformable sheet 70 is formed in a shape and dimensions equivalent to those of the insulating plate 50 in a plan view so as to overlap the entire area of ​​the insulating plate 50. The configurations of the first to third embodiments (Figs. 3 and 5) and the configuration of Fig. 10 are collectively expressed as a configuration in which the insulating plate 50 extends over the upper surface 10a and the lower surface 10b of the resin molded coil 10 in the Z-axis direction.

[0048] On the other hand, as illustrated in FIG. 11, a configuration is also assumed in which the insulating plate 50 is located in a part of the range between the upper surface 10a and the lower surface 10b of the resin molded coil 10 in the direction of the Z axis. In the configuration of FIG. 11, the upper surface 53 of the insulating plate 50 is located in the positive direction of the Z axis from the upper surface 10a of the resin molded coil 10, and the lower surface 54 of the insulating plate 50 is located in the negative direction of the Z axis from the lower surface 10b of the resin molded coil 10. The deformable sheet 70 is formed in a shape and size equivalent to the insulating plate 50 in a plan view so as to overlap the entire area of ​​the insulating plate 50. According to the above configuration, the size of the insulating plate 50 is reduced compared to the configuration (FIGS. 3, 5, and 10) in which the insulating plate 50 extends over the upper surface 10a and the lower surface 10b of the resin molded coil 10 in the direction of the Z axis. Therefore, there is an advantage that the manufacturing cost of the transformer 100 is reduced. Note that the deformable sheet 70 may be omitted in the configurations illustrated in FIG. 10 and FIG. 11. [Explanation of symbols]

[0049] 100... transformer, 10... resin molded coil, 10a... upper surface, 10b... lower surface, 11... high voltage molded coil, 12... low voltage molded coil, 13... opposing surface, 20... iron core, 21... first yoke portion, 22... second yoke portion, 23... legs, 23a... main legs, 23b... return legs, 30... support frame, 31... first support, 32... second support, 33... side support, 331... base portion, 332... side Surface portion, 333...side portion, 35,36...spacer, 40...installation base, 50...insulating plate, 51...first side of insulating plate, 52...second side of insulating plate, 53...top surface of insulating plate, 54...bottom surface of insulating plate, 55,56...side surface of insulating plate, 61...inner surface of return leg, 62...outer surface of return leg, 63...front surface of return leg, 64...rear surface of return leg, 70...deformable sheet, 71...first side of deformable sheet, 72...second side of deformable sheet.

Claims

[Claim 1] a core including a main landing gear and a return landing gear; a resin molded coil surrounding the main landing gear; A flat insulating plate is disposed between an outer peripheral surface of the resin molded coil and an inner surface of the return leg and is aligned along the inner surface of the return leg; a support body that supports the iron core while being in contact with an outer surface of the return leg; a deformable insulating sheet that is disposed between an outer peripheral surface of the resin molded coil and the insulating plate and is flexible compared to the insulating plate; Equipped with the insulating plate extends across an upper surface and a lower surface of the resin molded coil in an axial direction of the resin molded coil, a side surface of the insulating plate in a first direction parallel to an inner surface of the return leg and perpendicular to an axial direction of the resin molded coil is located outside the inner surface of the return leg in the first direction, The deformable sheet overlaps the entire insulating plate. Transformer.

Images