Transformers

Abstract

To provide a transformer capable of more simply and easily attaching a cover.SOLUTION: A transformer includes a primary coil 21, an inner secondary coil 7 and an outer secondary coil 6 arranged coaxially with the primary coil 21 inside and outside the primary coil 21, and a cover 5 that encloses the primary coil 21, the inner secondary coil 7, and the outer secondary coil 6, and the cover 5 includes a pair of members 3 and 4, and each of the members 3 and 4 includes two semi-cylindrical portions 3a, 3b, 4a, and 4b covering the primary coil 21, the inner secondary coil 7, and the outer secondary coil 6, and connecting portions 31 and 41 connecting the two semi-cylindrical portions 3a, 3b, 4a, and 4b.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] Conventionally, a transformer including an iron core, a primary coil, and a secondary coil has been proposed.

[0003] Patent Document 1 discloses a transformer that includes a resin bobbin having rectangular annular outer and inner frames, with grooves formed along the circumferential direction on the outer peripheral surfaces of the outer and inner frames, and with primary and secondary coils wound in each groove of the outer and inner frames. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-051034 Summary of the Invention [Problem to be solved by the invention]

[0005] Some transformers having multiple coils include a pair of covers that collectively bind the multiple coils. The covers are cylindrical and are provided at positions opposite to each other. Each cover surrounds an iron core.

[0006] However, the work of attaching the covers to cover multiple coils together is time-consuming, and since the above-mentioned transformer has a pair of covers, the work of attaching the covers must be performed twice, resulting in poor productivity.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a transformer in which the cover can be attached more simply and easily. [Means for solving the problem]

[0008] The transformer of the present invention comprises a first coil, a second coil and a third coil arranged coaxially with the first coil, on the inside and outside of the first coil, respectively, and a cover surrounding the first coil, the second coil, and the third coil, wherein the cover includes a pair of members, each of which has two semi-cylindrical portions covering the first coil, the second coil, and the third coil, and a connecting portion connecting the two semi-cylindrical portions.

[0009] In the present invention, the cover includes a pair of members, each having the two semi-cylindrical portions and the connecting portion, so that installation of the cover can be completed simply by combining the pair of members, thereby improving productivity.

[0010] In the transformer according to the present invention, a first positioning rib for determining the position of at least one of the second and third coils is formed on the inner surface of the semi-cylindrical portion.

[0011] In the present invention, when the second coil or the third coil is incorporated into the semi-cylindrical portion, the first positioning rib accurately determines the position of the second coil or the third coil, thereby improving the workability of incorporating the second coil or the third coil.

[0012] The transformer according to the present invention includes a bobbin around which the first coil is wound, and a second positioning rib for determining a position of the bobbin is formed on the inner surface of the semi-cylindrical portion.

[0013] In the present invention, when the bobbin is fitted to the semi-cylindrical portion, the position of the bobbin is accurately determined by the second positioning rib, so that the workability of fitting the bobbin can be improved.

[0014] The transformer according to the present invention includes an iron core provided around the semi-cylindrical portion, and the connecting portion has a plate shape and is interposed between the second coil and the iron core.

[0015] In the present invention, when the pair of members are combined, the connecting portion is interposed between the second coil and the iron core, and insulates the iron core from the second coil, eliminating the need for a separate insulating material and making it possible to omit the step of providing an insulating material between the iron core and the second coil.

[0016] In the transformer according to the present invention, the bobbin is formed with a recess that engages with the second positioning rib.

[0017] In the present invention, when the bobbin is assembled into the semi-cylindrical portion, the second positioning rib of the semi-cylindrical portion engages with the recess of the bobbin, thereby accurately determining the position of the bobbin, thereby improving the workability of the bobbin assembly work. Effect of the Invention

[0018] According to the present invention, it is possible to provide a transformer in which the cover can be attached more simply and easily. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view of a transformer according to an embodiment. [Diagram 2] FIG. 2 is an exploded view of the transformer according to the embodiment. [Diagram 3] FIG. 2 is a perspective view showing a first member of the transformer according to the embodiment. [Figure 4] FIG. 2 is a front view of a first member of the transformer according to the embodiment. [Diagram 5] FIG. 4 is a perspective view showing a second member of the transformer according to the embodiment. [Figure 6] 1A to 1C are diagrams illustrating an assembly process of a transformer according to an embodiment. [Figure 7] 1A to 1C are diagrams illustrating an assembly process of a transformer according to an embodiment. [Figure 8] 1A to 1C are diagrams illustrating an assembly process of a transformer according to an embodiment. [Figure 9] FIG. 2 is a cross-sectional view taken along line IX-IX in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The present invention will be described below with reference to the drawings showing a transformer according to an embodiment. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0021] FIG. 1 is a perspective view of a transformer 1 according to an embodiment. The transformer 1 includes a bobbin 2 around which a primary coil 21 is wound. An inner secondary coil 7 is disposed inside the bobbin 2, and an outer secondary coil 6 is disposed outside the bobbin 2. The transformer 1 also includes a cover 5 that partially surrounds the primary coil 21, the inner secondary coil 7, and the outer secondary coil 6, and an iron core 20 is provided around the cover 5.

[0022] Fig. 2 is an exploded view of the transformer 1 according to the embodiment. For convenience, the iron core 20 is not shown in Fig. 2. The bobbin 2 is made of resin and has a cylindrical core 26 and flanges 25 extending outward from both end edges of the core 26 in a direction intersecting with the axis. The flanges 25 are rectangular and annular. As a result, a recess 23 extending in the circumferential direction is formed on the outer circumferential surface of the core 26. The recess 23 is formed around the entire circumference of the bobbin 2. At the bottom of the recess 23, a plurality of partition walls 22 are formed protruding outward in the radial direction of the bobbin 2. Each partition wall 22 extends in the circumferential direction of the bobbin 2 and is provided around the entire circumference of the bobbin 2. As a result, a plurality of grooves are formed in the recess 23 in the thickness direction of the bobbin 2. A primary coil 21 (first coil) is wound in each groove.

[0023] An engaging recess 24 is provided on the outer surface of each flange 25 to engage with bobbin positioning ribs 33a, 33b, 43a, and 43b (see FIG. 9) of the cover 5, which will be described later. The engaging recess 24 is provided at two positions on both long sides of each flange 25, spaced apart in the longitudinal direction of each flange 25.

[0024] Each engagement recess 24 is formed in a cross shape by gaps between the four protrusions. More specifically, a pair of protrusions arranged in parallel at a predetermined interval in the short direction of the flange portion 25 are arranged at the same interval in the long direction of the flange portion 25. Since the engagement recess 24 engages with the bobbin positioning ribs 33a, 33b, 43a, and 43b, the shape of the engagement recess 24 is determined according to the shape of the corresponding bobbin positioning ribs 33a, 33b, 43a, and 43b.

[0025] A rectangular annular inner secondary coil 7 (second coil) is provided coaxially with the bobbin 2 radially inside the bobbin 2. The inner secondary coil 7 has a shape that protrudes inward in cross section. That is, the radial dimension of the outer periphery of the inner secondary coil 7 is slightly smaller than the radial dimension of the inner periphery of the core 26, and the axial dimension of the inner secondary coil 7 is smaller than the axial dimension of the core 26, i.e., the distance between the flanges 25.

[0026] An outer secondary coil 6 (third coil) having a rectangular ring shape is provided coaxially with the bobbin 2 on the radial outside of the bobbin 2. The outer secondary coil 6 has a shape that is convex outward in cross section. That is, the radial dimension of the inner circumference of the outer secondary coil 6 is slightly larger than the radial dimension of the outer circumference of the flange 25, and the axial dimension of the outer secondary coil 6 is smaller than the axial dimension of the core 26, i.e., the interval between the flanges 25.

[0027] The inner secondary coil 7 and the outer secondary coil 6 have a structure that retains their own shape, and can maintain the coil shape without a retaining mechanism such as a bobbin. The inner secondary coil 7 and the outer secondary coil 6 are formed, for example, by bending a rectangular wire. Instead of the rectangular wire, a wire group formed by integrating multiple round wires may be used.

[0028] The bobbin 2 (flange portion 25), the outer secondary coil 6, and the inner secondary coil 7 are each surrounded by a cover 5 having two cylindrical portions. As described above, a cylindrical iron core 20 is provided around each cylindrical portion of the cover 5.

[0029] The cover 5 is made of a polyamide resin-based material and is composed of a pair of parts, a first member 3 and a second member 4. The first member 3 and the second member 4 have a similar shape and correspond to each other. Below, only the first member 3 will be described, and a detailed description of the second member 4 will be omitted.

[0030] FIG. 3 is a perspective view showing the first member 3 of the transformer 1 according to the embodiment, and FIG. 4 is a front view of the first member 3 of the transformer 1 according to the embodiment.

[0031] The first member 3 has a semi-cylindrical portion 3a and a semi-cylindrical portion 3b, and two connecting portions 31 connecting the semi-cylindrical portion 3a and the semi-cylindrical portion 3b. The semi-cylindrical portion 3a and the semi-cylindrical portion 3b have their open sides facing the same direction, and are provided with a gap G between them so that their respective axes are parallel. The two connecting portions 31 are interposed in the gap G between the semi-cylindrical portion 3a and the semi-cylindrical portion 3b. The two connecting portions 31 are provided on both ends in a direction along the axis of the semi-cylindrical portion 3a and the semi-cylindrical portion 3b (hereinafter simply referred to as the axis direction), so as to face each other. Each connecting portion 31 is provided so as to bridge from the edge of the semi-cylindrical portion 3a to the edge of the semi-cylindrical portion 3b. For example, the two connecting portions 31 and the semi-cylindrical portion 3a and the semi-cylindrical portion 3b are integrally formed.

[0032] The semi-cylindrical portion 3a covers one long side of the bobbin 2 (flange portion 25), the outer secondary coil 6, and the inner secondary coil 7, and the semi-cylindrical portion 3b covers the other long side of the bobbin 2 (flange portion 25), the outer secondary coil 6, and the inner secondary coil 7 (see Figure 9).

[0033] Each of the connecting parts 31 is in the shape of a substantially trapezoidal plate, and has long and short sides extending parallel to the separation direction (hereinafter simply referred to as the separation direction) of the semi-cylindrical parts 3a and 3b. Each of the connecting parts 31 is provided with a comb-shaped rib on the non-opposing surface so that the open side faces the long side. The connecting part 31 is provided with a positioning protrusion 311 and a positioning recess 312 on the short side side for positioning when the first member 3 and the second member 4 are combined. The positioning protrusion 311 and the positioning recess 312 are provided at a predetermined interval in the separation direction. The positioning protrusion 311 has a shape corresponding to the positioning recess 412 of the second member 4, and the positioning recess 312 has a shape corresponding to the positioning protrusion 411 of the second member 4 (see FIG. 5).

[0034] An inner positioning rib 34a (first positioning rib) is provided on the inner surface of the semi-cylindrical portion 3a for positioning the inner secondary coil 7 when the inner secondary coil 7 is assembled. That is, the inner positioning rib 34a is provided at one end closer to the gap G among both ends in the circumferential direction (hereinafter simply referred to as the circumferential direction) of the semi-cylindrical portion 3a. The inner positioning rib 34a is provided at three locations in the axial direction, namely, both ends and a middle portion of the semi-cylindrical portion 3a. In this embodiment, an example in which the inner positioning rib 34a is provided at three locations will be described, but the present invention is not limited to this, and the number of locations may be two or less, or four or more.

[0035] Each of the inner positioning ribs 34a is plate-shaped, protrudes toward the axis of the semi-cylindrical portion 3a, and extends in the circumferential direction. As described above, since the inner secondary coil 7 has an inwardly convex shape in cross section, each of the inner positioning ribs 34a has a recess corresponding to the inner shape of the inner secondary coil 7.

[0036] In the semi-cylindrical portion 3a, an oval through hole 39a extending along the axial direction is formed between the inner positioning ribs 34a. That is, in the semi-cylindrical portion 3a, two through holes 39a are arranged side by side along the axial direction in a portion close to the gap G.

[0037] Two bobbin positioning ribs 33a (second positioning ribs) are provided on the inner surface of the semi-cylindrical portion 3a at the center in the circumferential direction. The bobbin positioning ribs 33a are, for example, cross-shaped and are provided at a predetermined interval in the axial direction. When the bobbin 2 is assembled, the bobbin positioning ribs 33a engage with the engagement recesses 24 of the bobbin 2 to position it.

[0038] Furthermore, on the inner surface of the semi-cylindrical portion 3a, at a position opposite to the position of the inner positioning rib 34a in the circumferential direction, an outer positioning rib 32a (first positioning rib) is provided for positioning the outer secondary coil 6 when the outer secondary coil 6 is assembled. That is, the outer positioning rib 32a is provided at the other end in the circumferential direction. The outer positioning rib 32a is provided at a position corresponding to the inner positioning rib 34a in the axial direction (see FIG. 4). In this embodiment, an example in which the outer positioning ribs 32a are provided at three locations will be described, but this is not limiting and the number of locations may be two or less, or four or more.

[0039] The outer positioning rib 32a has the same shape as the inner positioning rib 34a. That is, each outer positioning rib 32a is plate-shaped, protrudes toward the axis of the semi-cylindrical portion 3a, and extends in the circumferential direction of the semi-cylindrical portion 3a. As described above, since the outer secondary coil 6 has an outwardly convex shape in cross-sectional view, each outer positioning rib 32a has a concave portion corresponding to the outer shape of the outer secondary coil 6.

[0040] The semi-cylindrical portion 3a has a male prevention member 35a and a female prevention member 36a at the other circumferential end thereof, which prevent the first member 3 and the second member 4 from being separated after they are united. The male prevention member 35a is a generally rectangular plate-shaped member that narrows toward the tip and is provided at one end in the axial direction. The female prevention member 36a has a rectangular hole that corresponds to the male prevention member 45a of the second member 4 described below, and is provided at the other end in the axial direction.

[0041] In addition, in the semi-cylindrical portion 3a, a positioning claw 37 for positioning when the first member 3 and the second member 4 are combined is provided extending in the tangential direction of the outer circumferential surface of the semi-cylindrical portion 3a from the other circumferential end. The positioning claw 37 is rectangular and provided in the vicinity of the male prevention member 35a.

[0042] The semi-cylindrical portion 3b has a similar shape to the semi-cylindrical portion 3a. An inner positioning rib 34b (first positioning rib) is provided on the inner surface of the semi-cylindrical portion 3b for positioning the inner secondary coil 7 when the inner secondary coil 7 is assembled. That is, the inner positioning rib 34b is provided at one end of both ends in the circumferential direction of the semi-cylindrical portion 3b that is closer to the gap G. The inner positioning rib 34b is provided at three locations in the axial direction, at both ends and in the middle of the semi-cylindrical portion 3b. Each inner positioning rib 34b has the same shape as the inner positioning rib 34a of the semi-cylindrical portion 3a, and detailed description thereof will be omitted.

[0043] In the semi-cylindrical portion 3b, an oval through-hole 39b extending along the axial direction is formed in a portion close to the gap G and between the inner positioning ribs 34b (see FIG. 4).

[0044] Furthermore, two bobbin positioning ribs 33b (second positioning ribs) are provided protruding from the inner surface of the semi-cylindrical portion 3b at the center in the circumferential direction (see FIG. 4). The bobbin positioning ribs 33b extend linearly, for example, in the axial direction and are provided at a predetermined interval in the axial direction. When the bobbin 2 is assembled, the bobbin positioning ribs 33b engage with the engagement recesses 24 of the bobbin 2 to perform positioning.

[0045] In this embodiment, an example is given in which the bobbin positioning rib 33a on the semi-cylindrical portion 3a and the bobbin positioning rib 33b on the semi-cylindrical portion 3b have different shapes, but this is not limited to this and they may have the same shape.

[0046] Furthermore, on the inner surface of the semi-cylindrical portion 3b, at a position opposite to the position of the inner positioning rib 34b in the circumferential direction, an outer positioning rib 32b (first positioning rib) is provided for positioning the outer secondary coil 6 when the outer secondary coil 6 is assembled. That is, the outer positioning rib 32b is provided at the other end in the circumferential direction. The outer positioning rib 32b is provided at a position corresponding to the inner positioning rib 34b in the axial direction (see FIG. 4). The outer positioning rib 32b has the same shape as the outer positioning rib 32a of the semi-cylindrical portion 3a, and a detailed description thereof will be omitted.

[0047] The semi-cylindrical portion 3b has at its other circumferential end a male preventing member 35b and a female preventing member 36b that prevent the first member 3 and the second member 4 from being separated after they are united. The male preventing member 35b is provided at the other axial end, and the female preventing member 36b is provided at one axial end. The shapes of the male preventing member 35b and the female preventing member 36b are the same as those of the male preventing member 35a and the female preventing member 36a, and detailed explanations will be omitted.

[0048] In addition, a positioning recess 38 for positioning when the first member 3 and the second member 4 are combined is formed at the other circumferential end of the semi-cylindrical portion 3b. The positioning recess 38 is rectangular in shape corresponding to the positioning claw 47 of the second member 4, and is provided in the vicinity of the female prevention member 36b.

[0049] FIG. 5 is a perspective view showing the second member 4 of the transformer 1 according to the embodiment. As described above, the second member 4 has the same shape as the first member 3. The second member 4 has a semi-cylinder portion 4a, a semi-cylinder portion 4b, and two connecting portions 41 connecting the semi-cylinder portion 4a and the semi-cylinder portion 4b. The semi-cylinder portion 4a, the semi-cylinder portion 4b, and the connecting portion 41 of the second member 4 have the same shapes as the semi-cylinder portion 3a, the semi-cylinder portion 3b, and the connecting portion 31 of the first member 3, respectively, and detailed description thereof will be omitted.

[0050] Figures 6 to 8 are diagrams illustrating the assembly process of transformer 1 according to the embodiment. Also, Figure 9 is a cross-sectional view taken along line IX-IX in Figure 1. Hereinafter, the assembly process of transformer 1 will be described in detail with reference to Figures 6 to 9.

[0051] First, as shown in Fig. 6, the worker installs the bobbin 2 around which the primary coil 21 is wound into the second member 4. At this time, the worker engages the four engagement recesses 24 provided on one flange portion 25 of the bobbin 2 with the two bobbin positioning ribs 43a (second positioning ribs) of the semi-cylindrical portion 4a and the two bobbin positioning ribs 43b (second positioning ribs) of the semi-cylindrical portion 4b (see Fig. 9). This allows the position of the bobbin 2 to be correctly determined.

[0052] Next, as shown in Fig. 7, the worker installs the inner secondary coil 7 coaxially with the bobbin 2 on the radially inner side of the bobbin 2. At this time, the worker engages the inner side of the inner secondary coil 7 with the inner positioning rib 44a of the semi-cylindrical portion 4a and the inner positioning rib 44b of the semi-cylindrical portion 4b (see Fig. 9). This allows the position of the inner secondary coil 7 to be correctly determined.

[0053] Next, as shown in Fig. 7, the worker installs the outer secondary coil 6 on the radially outer side of the bobbin 2, coaxially with the bobbin 2. At this time, the worker engages the outer side of the outer secondary coil 6 with the outer positioning rib 42a of the semi-cylindrical portion 4a and the outer positioning rib 42b of the semi-cylindrical portion 4b (see Fig. 9). This allows the position of the outer secondary coil 6 to be correctly determined.

[0054] Then, as shown in FIG. 8, the worker combines the first member 3 with the second member 4. More specifically, the worker engages the positioning claw 37 of the first member 3 with the positioning recess 48 of the second member 4, and engages the positioning recess 38 of the first member 3 with the positioning claw 47 of the second member 4. The worker also presses the male preventing members 35a and 35b of the first member 3 into the female preventing members 46a and 46b of the second member 4, respectively, and presses the male preventing members 45a and 45b of the second member 4 into the female preventing members 36a and 36b of the first member 3. The worker then engages the positioning protrusion 311 of the first member 3 with the positioning recess 412 of the second member 4, and engages the positioning recess 312 of the first member 3 with the positioning protrusion 411 of the second member 4.

[0055] At this time, the four engagement recesses 24 provided on the other flange 25 of the bobbin 2 engage with the two bobbin positioning ribs 33a of the semi-cylindrical portion 3a and the two bobbin positioning ribs 33b of the semi-cylindrical portion 3b (see FIG. 9). The inside of the inner secondary coil 7 engages with the inner positioning rib 34a of the semi-cylindrical portion 3a and the inner positioning rib 34b of the semi-cylindrical portion 3b (see FIG. 9). Furthermore, the outside of the outer secondary coil 6 engages with the outer positioning rib 32a of the semi-cylindrical portion 3a and the outer positioning rib 32b of the semi-cylindrical portion 3b (see FIG. 9). The connecting portion 31 of the first member 3 is continuous with the connecting portion 41 of the second member 4 and is flush with it.

[0056] Thereafter, the worker attaches the iron core 20 around the cylindrical portion formed by the semi-cylindrical portion 3a of the first member 3 and the semi-cylindrical portion 4b of the second member 4, and the cylindrical portion formed by the semi-cylindrical portion 3b of the first member 3 and the semi-cylindrical portion 4a of the second member 4. For convenience, the iron core 20 is not shown in FIG.

[0057] As described above, in the transformer 1 according to this embodiment, the first member 3 has the semi-cylindrical portions 3a and 3b, and the second member 4 has the semi-cylindrical portions 4a and 4b, so that the cylindrical portion composed of the semi-cylindrical portions 3a and 4b, and the cylindrical portion composed of the semi-cylindrical portions 3b and 4a are simultaneously assembled simply by combining the first member 3 and the second member 4. This makes it simple and easy to install the cover 5 in the assembling process of the transformer 1, thereby improving the workability and productivity of assembling the transformer 1.

[0058] 1 and 8, in the transformer 1 according to this embodiment, when the assembly of the cover 5 is completed, the connecting portion 31 of the first member 3 and the connecting portion 41 of the second member 4 are present between the iron core 20 and the inner secondary coil 7. More specifically, the connecting portion 31 and the connecting portion 41 are present between both end faces of the iron core 20 and the inner surface of the inner secondary coil 7, and insulate the iron core 20 from the inner secondary coil 7. This eliminates the need for a separate insulating material and eliminates the need for a process of providing an insulating material between both end faces of the iron core 20 and the inner surface of the inner secondary coil 7, thereby improving the workability and productivity of assembling the transformer 1.

[0059] Furthermore, in the transformer 1 according to this embodiment, the first member 3 has through holes 39a, 39b formed therein, and the second member 4 has through holes 49a, 49b formed therein. That is, the through holes 39a, 39b in the first member 3 and the through holes 49a, 49b in the second member 4 are formed only on the inner secondary coil 7 side, avoiding the outer secondary coil 6 side. Therefore, the outer secondary coil 6 can be reliably insulated, and the weight of the cover 5 can be reduced while preventing adverse effects on peripheral devices.

[0060] In the present embodiment, the through holes 39a, 39b of the first member 3 and the through holes 49a, 49b of the second member 4 are each elliptical and there are two of them, but the present invention is not limited to this. They may have a shape other than an elliptical shape, and there may be one, or there may be three or more.

[0061] In the above, a case has been described in which the first member 3 is provided with the outer positioning ribs 32a, 32b and the inner positioning ribs 34a, 34b, and the second member 4 is provided with the outer positioning ribs 42a, 42b and the inner positioning ribs 44a, 44b, but the present invention is not limited to this. A configuration in which either the outer positioning ribs 32a, 32b or the inner positioning ribs 34a, 34b is provided on the first member 3, and either the outer positioning ribs 42a, 42b or the inner positioning ribs 44a, 44b is provided on the second member 4 may also be used.

[0062] The embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the scope of the claims and the scope equivalent to the claims. [Explanation of symbols]

[0063] 1; transformer; 2; bobbin; 3; first member; 3a, 3b; semi-cylindrical portion; 4; second member; 4a, 4b; semi-cylindrical portion; 5; cover; 6; outer secondary coil (third coil); 7; inner secondary coil (second coil); 20; iron core; 21; primary coil (first coil); 24; engagement recess; 31, 41; connecting portion; 33a, 33b, 43a, 43b; bobbin positioning rib (second positioning rib); 32a, 32b; outer positioning rib (first positioning rib); 34a, 34b; inner positioning rib (first positioning rib); 42a, 42b; outer positioning rib (first positioning rib); 44a, 44b; inner positioning rib (first positioning rib)

Claims

1. A transformer comprising: a first coil; a second coil and a third coil arranged coaxially with the first coil and on the inside and outside of the first coil, respectively; and a cover surrounding the first coil, the second coil, and the third coil, The cover includes a pair of members, Each component is Two semi-cylindrical parts covering the first coil, the second coil and the third coil; A connecting portion that connects the two semi-cylindrical portions. Transformer.

2. A first positioning rib is formed on the inner surface of the semi-cylindrical portion to determine the position of at least one of the second and third coils.

2. The transformer of claim 1.

3. a bobbin around which the first coil is wound; A second positioning rib for determining the position of the bobbin is formed on the inner surface of the semi-cylindrical portion.

3. A transformer according to claim 1 or 2.

4. The rotor includes an iron core disposed around the semi-cylindrical portion, The connecting portion has a plate shape and is interposed between the second coil and the iron core. A transformer according to any one of claims 1 to 3.

5. The bobbin is formed with a recess that engages with the second positioning rib.

4. The transformer according to claim 3.

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